1. 20 Apr, 2023 1 commit
    • YaacovHazan's avatar
      Misuse of bool in redis (#12077) · 74959a0f
      YaacovHazan authored
      We currently do not allow the use of bool type in redis project.
      
      We didn't catch it in script.c because we included hdr_histogram.h in server.h
      
      Removing it (but still having it in some c files) reducing
      the chance to miss the usage of bool type in the future and catch it
      in compiling stage.
      
      It also removes the dependency on hdr_histogram for every unit
      that includes server.h
      74959a0f
  2. 12 Apr, 2023 1 commit
    • Binbin's avatar
      Add RM_ReplyWithErrorFormat that can support format (#11923) · bfec2d70
      Binbin authored
      * Add RM_ReplyWithErrorFormat that can support format
      
      Reply with the error create from a printf format and arguments.
      
      If the error code is already passed in the string 'fmt', the error
      code provided is used, otherwise the string "-ERR " for the generic
      error code is automatically added.
      
      The usage is, for example:
          RedisModule_ReplyWithErrorFormat(ctx, "An error: %s", "foo");
          RedisModule_ReplyWithErrorFormat(ctx, "-WRONGTYPE Wrong Type: %s", "foo");
      
      The function always returns REDISMODULE_OK.
      bfec2d70
  3. 10 Apr, 2023 1 commit
    • sundb's avatar
      Use dummy allocator to make accesses defined as per standard (#11982) · e0b378d2
      sundb authored
      
      
      ## Issue
      When we use GCC-12 later or clang 9.0 later to build with `-D_FORTIFY_SOURCE=3`,
      we can see the following buffer overflow:
      ```
      === REDIS BUG REPORT START: Cut & paste starting from here ===
      6263:M 06 Apr 2023 08:59:12.915 # Redis 255.255.255 crashed by signal: 6, si_code: -6
      6263:M 06 Apr 2023 08:59:12.915 # Crashed running the instruction at: 0x7f03d59efa7c
      
      ------ STACK TRACE ------
      EIP:
      /lib/x86_64-linux-gnu/libc.so.6(pthread_kill+0x12c)[0x7f03d59efa7c]
      
      Backtrace:
      /lib/x86_64-linux-gnu/libc.so.6(+0x42520)[0x7f03d599b520]
      /lib/x86_64-linux-gnu/libc.so.6(pthread_kill+0x12c)[0x7f03d59efa7c]
      /lib/x86_64-linux-gnu/libc.so.6(raise+0x16)[0x7f03d599b476]
      /lib/x86_64-linux-gnu/libc.so.6(abort+0xd3)[0x7f03d59817f3]
      /lib/x86_64-linux-gnu/libc.so.6(+0x896f6)[0x7f03d59e26f6]
      /lib/x86_64-linux-gnu/libc.so.6(__fortify_fail+0x2a)[0x7f03d5a8f76a]
      /lib/x86_64-linux-gnu/libc.so.6(+0x1350c6)[0x7f03d5a8e0c6]
      src/redis-server 127.0.0.1:25111(+0xd5e80)[0x557cddd3be80]
      src/redis-server 127.0.0.1:25111(feedReplicationBufferWithObject+0x78)[0x557cddd3c768]
      src/redis-server 127.0.0.1:25111(replicationFeedSlaves+0x1a4)[0x557cddd3cbc4]
      src/redis-server 127.0.0.1:25111(+0x8721a)[0x557cddced21a]
      src/redis-server 127.0.0.1:25111(call+0x47a)[0x557cddcf38ea]
      src/redis-server 127.0.0.1:25111(processCommand+0xbf4)[0x557cddcf4aa4]
      src/redis-server 127.0.0.1:25111(processInputBuffer+0xe6)[0x557cddd22216]
      src/redis-server 127.0.0.1:25111(readQueryFromClient+0x3a8)[0x557cddd22898]
      src/redis-server 127.0.0.1:25111(+0x1b9134)[0x557cdde1f134]
      src/redis-server 127.0.0.1:25111(aeMain+0x119)[0x557cddce5349]
      src/redis-server 127.0.0.1:25111(main+0x466)[0x557cddcd6716]
      /lib/x86_64-linux-gnu/libc.so.6(+0x29d90)[0x7f03d5982d90]
      /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0x80)[0x7f03d5982e40]
      src/redis-server 127.0.0.1:25111(_start+0x25)[0x557cddcd7025]
      ```
      
      The main reason is that when FORTIFY_SOURCE is enabled, GCC or clang will enhance some
      common functions, such as `strcpy`, `memcpy`, `fgets`, etc, so that they can detect buffer
      overflow errors and stop program execution, thus improving the safety of the program.
      We use `zmalloc_usable_size()` everywhere to use memory blocks, but that is an abuse since the
      malloc_usable_size() isn't meant for this kind of use, it is for diagnostics only. That is also why the
      behavior is flaky when built with _FORTIFY_SOURCE, the compiler can sense that we reach outside
      the allocated block and SIGABRT.
      
      ### Solution
      If we need to use the additional memory we got, we need to use a dummy realloc with `alloc_size` attribute
      and no inlining, (see `extend_to_usable`) to let the compiler see the large of memory we need to use.
      This can either be an implicit call inside `z*usable` that returns the size, so that the caller doesn't have any
      other worry, or it can be a normal zmalloc call which means that if the caller wants to use
      zmalloc_usable_size it must also use extend_to_usable.
      
      ### Changes
      
      This PR does the following:
      1) rename the current z[try]malloc_usable family to z[try]malloc_internal and don't expose them to users outside zmalloc.c,
      2) expose a new set of `z[*]_usable` family that use z[*]_internal and `extend_to_usable()` implicitly, the caller gets the
        size of the allocation and it is safe to use.
      3) go over all the users of `zmalloc_usable_size` and convert them to use the `z[*]_usable` family if possible.
      4) in the places where the caller can't use `z[*]_usable` and store the real size, and must still rely on zmalloc_usable_size,
        we still make sure that the allocation used `z[*]_usable` (which has a call to `extend_to_usable()`) and ignores the
        returning size, this way a later call to `zmalloc_usable_size` is still safe.
      
      [4] was done for module.c and listpack.c, all the others places (sds, reply proto list, replication backlog, client->buf)
      are using [3].
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      e0b378d2
  4. 09 Apr, 2023 1 commit
    • Ozan Tezcan's avatar
      Add RM_RdbLoad and RM_RdbSave module API functions (#11852) · e55568ed
      Ozan Tezcan authored
      Add `RM_RdbLoad()` and `RM_RdbSave()` to load/save RDB files from the module API. 
      
      In our use case, we have our clustering implementation as a module. As part of this
      implementation, the module needs to trigger RDB save operation at specific points.
      Also, this module delivers RDB files to other nodes (not using Redis' replication).
      When a node receives an RDB file, it should be able to load the RDB. Currently,
      there is no module API to save/load RDB files. 
      
      
      This PR adds four new APIs:
      ```c
      RedisModuleRdbStream *RM_RdbStreamCreateFromFile(const char *filename);
      void RM_RdbStreamFree(RedisModuleRdbStream *stream);
      
      int RM_RdbLoad(RedisModuleCtx *ctx, RedisModuleRdbStream *stream, int flags);
      int RM_RdbSave(RedisModuleCtx *ctx, RedisModuleRdbStream *stream, int flags);
      ```
      
      The first step is to create a `RedisModuleRdbStream` object. This PR provides a function to
      create RedisModuleRdbStream from the filename. (You can load/save RDB with the filename).
      In the future, this API can be extended if needed: 
      e.g., `RM_RdbStreamCreateFromFd()`, `RM_RdbStreamCreateFromSocket()` to save/load
      RDB from an `fd` or a `socket`. 
      
      
      Usage:
      ```c
      /* Save RDB */
      RedisModuleRdbStream *stream = RedisModule_RdbStreamCreateFromFile("example.rdb");
      RedisModule_RdbSave(ctx, stream, 0);
      RedisModule_RdbStreamFree(stream);
      
      /* Load RDB */
      RedisModuleRdbStream *stream = RedisModule_RdbStreamCreateFromFile("example.rdb");
      RedisModule_RdbLoad(ctx, stream, 0);
      RedisModule_RdbStreamFree(stream);
      ```
      e55568ed
  5. 30 Mar, 2023 2 commits
    • Jason Elbaum's avatar
      Reimplement cli hints based on command arg docs (#10515) · 1f76bb17
      Jason Elbaum authored
      
      
      Now that the command argument specs are available at runtime (#9656), this PR addresses
      #8084 by implementing a complete solution for command-line hinting in `redis-cli`.
      
      It correctly handles nearly every case in Redis's complex command argument definitions, including
      `BLOCK` and `ONEOF` arguments, reordering of optional arguments, and repeated arguments
      (even when followed by mandatory arguments). It also validates numerically-typed arguments.
      It may not correctly handle all possible combinations of those, but overall it is quite robust.
      
      Arguments are only matched after the space bar is typed, so partial word matching is not
      supported - that proved to be more confusing than helpful. When the user's current input
      cannot be matched against the argument specs, hinting is disabled.
      
      Partial support has been implemented for legacy (pre-7.0) servers that do not support
      `COMMAND DOCS`, by falling back to a statically-compiled command argument table.
      On startup, if the server does not support `COMMAND DOCS`, `redis-cli` will now issue
      an `INFO SERVER` command to retrieve the server version (unless `HELLO` has already
      been sent, in which case the server version will be extracted from the reply to `HELLO`).
      The server version will be used to filter the commands and arguments in the command table,
      removing those not supported by that version of the server. However, the static table only
      includes core Redis commands, so with a legacy server hinting will not be supported for
      module commands. The auto generated help.h and the scripts that generates it are gone.
      
      Command and argument tables for the server and CLI use different structs, due primarily
      to the need to support different runtime data. In order to generate code for both, macros
      have been added to `commands.def` (previously `commands.c`) to make it possible to
      configure the code generation differently for different use cases (one linked with redis-server,
      and one with redis-cli).
      
      Also adding a basic testing framework for the command hints based on new (undocumented)
      command line options to `redis-cli`: `--test_hint 'INPUT'` prints out the command-line hint for
      a given input string, and `--test_hint_file <filename>` runs a suite of test cases for the hinting
      mechanism. The test suite is in `tests/assets/test_cli_hint_suite.txt`, and it is run from
      `tests/integration/redis-cli.tcl`.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarViktor Söderqvist <viktor.soderqvist@est.tech>
      1f76bb17
    • Madelyn Olson's avatar
      Fixed tracking of command duration for multi/eval/module/wait (#11970) · 971b177f
      Madelyn Olson authored
      In #11012, we changed the way command durations were computed to handle the same command being executed multiple times. This commit fixes some misses from that commit.
      
      * Wait commands were not correctly reporting their duration if the timeout was reached.
      * Multi/scripts/and modules with RM_Call were not properly resetting the duration between inner calls, leading to them reporting cumulative duration.
      * When a blocked client is freed, the call and duration are always discarded.
      
      This commit also adds an assert if the duration is not properly reset, potentially indicating that a report to call statistics was missed. The assert potentially be removed in the future, as it's mainly intended to detect misses in tests.
      971b177f
  6. 21 Mar, 2023 1 commit
    • Roshan Khatri's avatar
      Module commands to have ACL categories. (#11708) · 6948daca
      Roshan Khatri authored
      
      
      This allows modules to register commands to existing ACL categories and blocks the creation of [sub]commands, datatypes and registering the configs outside of the OnLoad function.
      
      For allowing modules to register commands to existing ACL categories,
      This PR implements a new API int RM_SetCommandACLCategories() which takes a pointer to a RedisModuleCommand and a C string aclflags containing the set of space separated ACL categories.
      Example, 'write slow' marks the command as part of the write and slow ACL categories.
      
      The C string aclflags is tokenized by implementing a helper function categoryFlagsFromString(). Theses tokens are matched and the corresponding ACL categories flags are set by a helper function matchAclCategoriesFlags. The helper function categoryFlagsFromString() returns the corresponding categories_flags or returns -1 if some token not processed correctly.
      
      If the module contains commands which are registered to existing ACL categories, the number of [sub]commands are tracked by num_commands_with_acl_categories in struct RedisModule. Further, the allowed command bit-map of the existing users are recomputed from the command_rules list, by implementing a function called ACLRecomputeCommandBitsFromCommandRulesAllUsers() for the existing users to have access to the module commands on runtime.
      
      ## Breaking change
      This change requires that registering commands and subcommands only occur during a modules "OnLoad" function, in order to allow efficient recompilation of ACL bits. We also chose to block registering configs and types, since we believe it's only valid for those to be created during onLoad. We check for this onload flag in struct RedisModule to check if the call is made from the OnLoad function.
      Co-authored-by: default avatarMadelyn Olson <madelyneolson@gmail.com>
      6948daca
  7. 16 Mar, 2023 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Support for RM_Call on blocking commands (#11568) · d0da0a6a
      Meir Shpilraien (Spielrein) authored
      Allow running blocking commands from within a module using `RM_Call`.
      
      Today, when `RM_Call` is used, the fake client that is used to run command
      is marked with `CLIENT_DENY_BLOCKING` flag. This flag tells the command
      that it is not allowed to block the client and in case it needs to block, it must
      fallback to some alternative (either return error or perform some default behavior).
      For example, `BLPOP` fallback to simple `LPOP` if it is not allowed to block.
      
      All the commands must respect the `CLIENT_DENY_BLOCKING` flag (including
      module commands). When the command invocation finished, Redis asserts that
      the client was not blocked.
      
      This PR introduces the ability to call blocking command using `RM_Call` by
      passing a callback that will be called when the client will get unblocked.
      In order to do that, the user must explicitly say that he allow to perform blocking
      command by passing a new format specifier argument, `K`, to the `RM_Call`
      function. This new flag will tell Redis that it is allow to run blocking command
      and block the client. In case the command got blocked, Redis will return a new
      type of call reply (`REDISMODULE_REPLY_PROMISE`). This call reply indicates
      that the command got blocked and the user can set the on_unblocked handler using
      `RM_CallReplyPromiseSetUnblockHandler`.
      
      When clients gets unblocked, it eventually reaches `processUnblockedClients` function.
      This is where we check if the client is a fake module client and if it is, we call the unblock
      callback instead of performing the usual unblock operations.
      
      **Notice**: `RM_CallReplyPromiseSetUnblockHandler` must be called atomically
      along side the command invocation (without releasing the Redis lock in between).
      In addition, unlike other CallReply types, the promise call reply must be released
      by the module when the Redis GIL is acquired.
      
      The module can abort the execution on the blocking command (if it was not yet
      executed) using `RM_CallReplyPromiseAbort`. the API will return `REDISMODULE_OK`
      on success and `REDISMODULE_ERR` if the operation is already executed.
      **Notice** that in case of misbehave module, Abort might finished successfully but the
      operation will not really be aborted. This can only happened if the module do not respect
      the disconnect callback of the blocked client. 
      For pure Redis commands this can not happened.
      
      ### Atomicity Guarantees
      
      The API promise that the unblock handler will run atomically as an execution unit.
      This means that all the operation performed on the unblock handler will be wrapped
      with a multi exec transaction when replicated to the replica and AOF.
      The API **do not** grantee any other atomicity properties such as when the unblock
      handler will be called. This gives us the flexibility to strengthen the grantees (or not)
      in the future if we will decide that we need a better guarantees.
      
      That said, the implementation **does** provide a better guarantees when performing
      pure Redis blocking command like `BLPOP`. In this case the unblock handler will run
      atomically with the operation that got unblocked (for example, in case of `BLPOP`, the
      unblock handler will run atomically with the `LPOP` operation that run when the command
      got unblocked). This is an implementation detail that might be change in the future and the
      module writer should not count on that.
      
      ### Calling blocking commands while running on script mode (`S`)
      
      `RM_Call` script mode (`S`) was introduced on #0372. It is used for usecases where the
      command that was invoked on `RM_Call` comes from a user input and we want to make
      sure the user will not run dangerous commands like `shutdown`. Some command, such
      as `BLPOP`, are marked with `NO_SCRIPT` flag, which means they will not be allowed on
      script mode. Those commands are marked with  `NO_SCRIPT` just because they are
      blocking commands and not because they are dangerous. Now that we can run blocking
      commands on RM_Call, there is no real reason not to allow such commands on script mode.
      
      The underline problem is that the `NO_SCRIPT` flag is abused to also mark some of the
      blocking commands (notice that those commands know not to block the client if it is not
      allowed to do so, and have a fallback logic to such cases. So even if those commands
      were not marked with `NO_SCRIPT` flag, it would not harm Redis, and today we can
      already run those commands within multi exec).
      
      In addition, not all blocking commands are marked with `NO_SCRIPT` flag, for example
      `blmpop` are not marked and can run from within a script.
      
      Those facts shows that there are some ambiguity about the meaning of the `NO_SCRIPT`
      flag, and its not fully clear where it should be use.
      
      The PR suggest that blocking commands should not be marked with `NO_SCRIPT` flag,
      those commands should handle `CLIENT_DENY_BLOCKING` flag and only block when
      it's safe (like they already does today). To achieve that, the PR removes the `NO_SCRIPT`
      flag from the following commands:
      * `blmove`
      * `blpop`
      * `brpop`
      * `brpoplpush`
      * `bzpopmax`
      * `bzpopmin`
      * `wait`
      
      This might be considered a breaking change as now, on scripts, instead of getting
      `command is not allowed from script` error, the user will get some fallback behavior
      base on the command implementation. That said, the change matches the behavior
      of scripts and multi exec with respect to those commands and allow running them on
      `RM_Call` even when script mode is used.
      
      ### Additional RedisModule API and changes
      
      * `RM_BlockClientSetPrivateData` - Set private data on the blocked client without the
        need to unblock the client. This allows up to set the promise CallReply as the private
        data of the blocked client and abort it if the client gets disconnected.
      * `RM_BlockClientGetPrivateData` - Return the current private data set on a blocked client.
        We need it so we will have access to this private data on the disconnect callback.
      * On RM_Call, the returned reply will be added to the auto memory context only if auto
        memory is enabled, this allows us to keep the call reply for longer time then the context
        lifetime and does not force an unneeded borrow relationship between the CallReply and
        the RedisModuleContext.
      d0da0a6a
  8. 15 Mar, 2023 2 commits
    • KarthikSubbarao's avatar
      Custom authentication for Modules (#11659) · f8a5a4f7
      KarthikSubbarao authored
      
      
      This change adds new module callbacks that can override the default password based authentication associated with ACLs. With this, Modules can register auth callbacks through which they can implement their own Authentication logic. When `AUTH` and `HELLO AUTH ...` commands are used, Module based authentication is attempted and then normal password based authentication is attempted if needed.
      The new Module APIs added in this PR are - `RM_RegisterCustomAuthCallback` and `RM_BlockClientOnAuth` and `RedisModule_ACLAddLogEntryByUserName `.
      
      Module based authentication will be attempted for all Redis users (created through the ACL SETUSER cmd or through Module APIs) even if the Redis user does not exist at the time of the command. This gives a chance for the Module to create the RedisModule user and then authenticate via the RedisModule API - from the custom auth callback.
      
      For the AUTH command, we will support both variations - `AUTH <username> <password>` and `AUTH <password>`. In case of the `AUTH <password>` variation, the custom auth callbacks are triggered with “default” as the username and password as what is provided.
      
      
      ### RedisModule_RegisterCustomAuthCallback
      ```
      void RM_RegisterCustomAuthCallback(RedisModuleCtx *ctx, RedisModuleCustomAuthCallback cb) {
      ```
      This API registers a callback to execute to prior to normal password based authentication. Multiple callbacks can be registered across different modules. These callbacks are responsible for either handling the authentication, each authenticating the user or explicitly denying, or deferring it to other authentication mechanisms. Callbacks are triggered in the order they were registered. When a Module is unloaded, all the auth callbacks registered by it are unregistered. The callbacks are attempted, in the order of most recently registered callbacks, when the AUTH/HELLO (with AUTH field is provided) commands are called. The callbacks will be called with a module context along with a username and a password, and are expected to take one of the following actions:
      
       (1) Authenticate - Use the RM_Authenticate* API successfully and return `REDISMODULE_AUTH_HANDLED`. This will immediately end the auth chain as successful and add the OK reply.
      (2) Block a client on authentication - Use the `RM_BlockClientOnAuth` API and return `REDISMODULE_AUTH_HANDLED`. Here, the client will be blocked until the `RM_UnblockClient `API is used which will trigger the auth reply callback (provided earlier through the `RM_BlockClientOnAuth`). In this reply callback, the Module should authenticate, deny or skip handling authentication.
      (3) Deny Authentication - Return `REDISMODULE_AUTH_HANDLED` without authenticating or blocking the client. Optionally, `err` can be set to a custom error message. This will immediately end the auth chain as unsuccessful and add the ERR reply.
      (4) Skip handling Authentication - Return `REDISMODULE_AUTH_NOT_HANDLED` without blocking the client. This will allow the engine to attempt the next custom auth callback.
      
      If none of the callbacks authenticate or deny auth, then password based auth is attempted and will authenticate or add failure logs and reply to the clients accordingly.
      
      ### RedisModule_BlockClientOnAuth
      ```
      RedisModuleBlockedClient *RM_BlockClientOnAuth(RedisModuleCtx *ctx, RedisModuleCustomAuthCallback reply_callback,
                                                     void (*free_privdata)(RedisModuleCtx*,void*))
      ```
      This API can only be used from a Module from the custom auth callback. If a client is not in the middle of custom module based authentication, ERROR is returned. Otherwise, the client is blocked and the `RedisModule_BlockedClient` is returned similar to the `RedisModule_BlockClient` API.
      
      ### RedisModule_ACLAddLogEntryByUserName
      ```
      int RM_ACLAddLogEntryByUserName(RedisModuleCtx *ctx, RedisModuleString *username, RedisModuleString *object, RedisModuleACLLogEntryReason reason)
      ```
      Adds a new entry in the ACL log with the `username` RedisModuleString provided. This simplifies the Module usage because now, developers do not need to create a Module User just to add an error ACL Log entry. Aside from accepting username (RedisModuleString) instead of a RedisModuleUser, it is the same as the existing `RedisModule_ACLAddLogEntry` API.
      
      
      ### Breaking changes
      - HELLO command - Clients can now only set the client name and RESP protocol from the `HELLO` command if they are authenticated. Also, we now finish command arg validation first and return early with a ERR reply if any arg is invalid. This is to avoid mutating the client name / RESP from a command that would have failed on invalid arguments.
      
      ### Notable behaviors
      - Module unblocking - Now, we will not allow Modules to block the client from inside the context of a reply callback (triggered from the Module unblock flow `moduleHandleBlockedClients`).
      
      ---------
      Co-authored-by: default avatarMadelyn Olson <34459052+madolson@users.noreply.github.com>
      f8a5a4f7
    • Kaige Ye's avatar
      cleanup NBSP characters in comments (#10555) · 5360350e
      Kaige Ye authored
      Replace NBSP character (0xC2 0xA0) with space (0x20).
      
      Looks like that was originally added due to misconfigured editor which seems to have been fixed by now.
      5360350e
  9. 28 Feb, 2023 1 commit
    • uriyage's avatar
      Try to trim strings only when applicable (#11817) · 9d336ac3
      uriyage authored
      
      
      As `sdsRemoveFreeSpace` have an impact on performance even if it is a no-op (see details at #11508). 
      Only call the function when there is a possibility that the string contains free space.
      * For strings coming from the network, it's only if they're bigger than PROTO_MBULK_BIG_ARG
      * For strings coming from scripts, it's only if they're smaller than LUA_CMD_OBJCACHE_MAX_LEN
      * For strings coming from modules, it could be anything.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarsundb <sundbcn@gmail.com>
      9d336ac3
  10. 16 Feb, 2023 1 commit
    • Oran Agra's avatar
      Cleanup around script_caller, fix tracking of scripts and ACL logging for RM_Call (#11770) · 233abbbe
      Oran Agra authored
      * Make it clear that current_client is the root client that was called by
        external connection
      * add executing_client which is the client that runs the current command
        (can be a module or a script)
      * Remove script_caller that was used for commands that have CLIENT_SCRIPT
        to get the client that called the script. in most cases, that's the current_client,
        and in others (when being called from a module), it could be an intermediate
        client when we actually want the original one used by the external connection.
      
      bugfixes:
      * RM_Call with C flag should log ACL errors with the requested user rather than
        the one used by the original client, this also solves a crash when RM_Call is used
        with C flag from a detached thread safe context.
      * addACLLogEntry would have logged info about the script_caller, but in case the
        script was issued by a module command we actually want the current_client. the
        exception is when RM_Call is called from a timer event, in which case we don't
        have a current_client.
      
      behavior changes:
      * client side tracking for scripts now tracks the keys that are read by the script
        instead of the keys that are declared by the caller for EVAL
      
      other changes:
      * Log both current_client and executing_client in the crash log.
      * remove prepareLuaClient and resetLuaClient, being dead code that was forgotten.
      * remove scriptTimeSnapshot and snapshot_time and instead add cmd_time_snapshot
        that serves all commands and is reset only when execution nesting starts.
      * remove code to propagate CLIENT_FORCE_REPL from the executed command
        to the script caller since scripts aren't propagated anyway these days and anyway
        this flag wouldn't have had an effect since CLIENT_PREVENT_PROP is added by scriptResetRun.
      * fix a module GIL violation issue in afterSleep that was introduced in #10300 (unreleased)
      233abbbe
  11. 09 Feb, 2023 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Match REDISMODULE_OPEN_KEY_* flags to LOOKUP_* flags (#11772) · 5c3938d5
      Meir Shpilraien (Spielrein) authored
      The PR adds support for the following flags on RedisModule_OpenKey:
      
      * REDISMODULE_OPEN_KEY_NONOTIFY - Don't trigger keyspace event on key misses.
      * REDISMODULE_OPEN_KEY_NOSTATS - Don't update keyspace hits/misses counters.
      * REDISMODULE_OPEN_KEY_NOEXPIRE - Avoid deleting lazy expired keys.
      * REDISMODULE_OPEN_KEY_NOEFFECTS - Avoid any effects from fetching the key
      
      In addition, added `RM_GetOpenKeyModesAll`, which returns the mask of all
      supported OpenKey modes. This allows the module to check, in runtime, which
      OpenKey modes are supported by the current Redis instance.
      5c3938d5
  12. 31 Jan, 2023 1 commit
    • uriyage's avatar
      Optimization: sdsRemoveFreeSpace to avoid realloc on noop (#11766) · 46393f98
      uriyage authored
      
      
      In #7875 (Redis 6.2), we changed the sds alloc to be the usable allocation
      size in order to:
      
      > reduce the need for realloc calls by making the sds implicitly take over
      the internal fragmentation
      
      This change was done most sds functions, excluding `sdsRemoveFreeSpace` and
      `sdsResize`, the reason is that in some places (e.g. clientsCronResizeQueryBuffer)
      we call sdsRemoveFreeSpace when we see excessive free space and want to trim it.
      so if we don't trim it exactly to size, the caller may still see excessive free space and
      call it again and again.
      
      However, this resulted in some excessive calls to realloc, even when there's no need
      and it's gonna be a no-op (e.g. when reducing 15 bytes allocation to 13).
      
      It turns out that a call for realloc with jemalloc can be expensive even if it ends up
      doing nothing, so this PR adds a check using `je_nallocx`, which is cheap to avoid
      the call for realloc.
      
      in addition to that this PR unifies sdsResize and sdsRemoveFreeSpace into common
      code. the difference between them was that sdsResize would avoid using SDS_TYPE_5,
      since it want to keep the string ready to be resized again, while sdsRemoveFreeSpace
      would permit using SDS_TYPE_5 and get an optimal memory consumption.
      now both methods take a `would_regrow` argument that makes it more explicit.
      
      the only actual impact of that is that in clientsCronResizeQueryBuffer we call both sdsResize
      and sdsRemoveFreeSpace for in different cases, and we now prevent the use of SDS_TYPE_5 in both.
      
      The new test that was added to cover this concern used to pass before this PR as well,
      this PR is just a performance optimization and cleanup.
      
      Benchmark:
      `redis-benchmark -c 100 -t set  -d 512 -P 10  -n  100000000`
      on i7-9850H with jemalloc, shows improvement from 1021k ops/sec to 1067k (average of 3 runs).
      some 4.5% improvement.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      46393f98
  13. 11 Jan, 2023 2 commits
    • Viktor Söderqvist's avatar
      Move stat_active_defrag_hits increment to activeDefragAlloc · 2bbc8919
      Viktor Söderqvist authored
      instead of passing it around to every defrag function
      2bbc8919
    • Viktor Söderqvist's avatar
      Remove the bucket-cb from dictScan and move dictEntry defrag to dictScanDefrag · b60d33c9
      Viktor Söderqvist authored
      This change deletes the dictGetNext and dictGetNextRef functions, so the
      dict API doesn't expose the next field at all.
      
      The bucket function in dictScan is deleted. A separate dictScanDefrag function
      is added which takes a defrag alloc function to defrag-reallocate the dict entries.
      
      "Dirty" code accessing the dict internals in active defrag is removed.
      
      An 'afterReplaceEntry' is added to dictType, which allows the dict user
      to keep the dictEntry metadata up to date after reallocation/defrag/move.
      
      Additionally, for updating the cluster slot-to-key mapping, after a dictEntry
      has been reallocated, we need to know which db a dict belongs to, so we store
      a pointer to the db in a new metadata section in the dict struct, which is
      a new mechanism similar to dictEntry metadata. This adds some complexity but
      provides better isolation.
      b60d33c9
  14. 04 Jan, 2023 1 commit
    • Oran Agra's avatar
      Fix potential issue with Lua argv caching, module command filter and libc realloc (#11652) · c8052122
      Oran Agra authored
      TLDR: solve a problem introduced in Redis 7.0.6 (#11541) with
      RM_CommandFilterArgInsert being called from scripts, which can
      lead to memory corruption.
      
      Libc realloc can return the same pointer even if the size was changed. The code in
      freeLuaRedisArgv had an assumption that if the pointer didn't change, then the
      allocation didn't change, and the cache can still be reused.
      However, if rewriteClientCommandArgument or RM_CommandFilterArgInsert were
      used, it could be that we realloced the argv array, and the pointer didn't change, then
      a consecutive command being executed from Lua can use that argv cache reaching
      beyond its size.
      This was actually only possible with modules, since the decision to realloc was based
      on argc, rather than argv_len.
      c8052122
  15. 01 Jan, 2023 1 commit
    • ranshid's avatar
      reprocess command when client is unblocked on keys (#11012) · 383d902c
      ranshid authored
      *TL;DR*
      ---------------------------------------
      Following the discussion over the issue [#7551](https://github.com/redis/redis/issues/7551
      
      )
      We decided to refactor the client blocking code to eliminate some of the code duplications
      and to rebuild the infrastructure better for future key blocking cases.
      
      
      *In this PR*
      ---------------------------------------
      1. reprocess the command once a client becomes unblocked on key (instead of running
         custom code for the unblocked path that's different than the one that would have run if
         blocking wasn't needed)
      2. eliminate some (now) irrelevant code for handling unblocking lists/zsets/streams etc...
      3. modify some tests to intercept the error in cases of error on reprocess after unblock (see
         details in the notes section below)
      4. replace '$' on the client argv with current stream id. Since once we reprocess the stream
         XREAD we need to read from the last msg and not wait for new msg  in order to prevent
         endless block loop. 
      5. Added statistics to the info "Clients" section to report the:
         * `total_blocking_keys` - number of blocking keys
         * `total_blocking_keys_on_nokey` - number of blocking keys which have at least 1 client
            which would like
         to be unblocked on when the key is deleted.
      6. Avoid expiring unblocked key during unblock. Previously we used to lookup the unblocked key
         which might have been expired during the lookup. Now we lookup the key using NOTOUCH and
         NOEXPIRE to avoid deleting it at this point, so propagating commands in blocked.c is no longer needed.
      7. deprecated command flags. We decided to remove the CMD_CALL_STATS and CMD_CALL_SLOWLOG
         and make an explicit verification in the call() function in order to decide if stats update should take place.
         This should simplify the logic and also mitigate existing issues: for example module calls which are
         triggered as part of AOF loading might still report stats even though they are called during AOF loading.
      
      *Behavior changes*
      ---------------------------------------------------
      
      1. As this implementation prevents writing dedicated code handling unblocked streams/lists/zsets,
      since we now re-process the command once the client is unblocked some errors will be reported differently.
      The old implementation used to issue
      ``UNBLOCKED the stream key no longer exists``
      in the following cases:
         - The stream key has been deleted (ie. calling DEL)
         - The stream and group existed but the key type was changed by overriding it (ie. with set command)
         - The key not longer exists after we swapdb with a db which does not contains this key
         - After swapdb when the new db has this key but with different type.
         
      In the new implementation the reported errors will be the same as if the command was processed after effect:
      **NOGROUP** - in case key no longer exists, or **WRONGTYPE** in case the key was overridden with a different type.
      
      2. Reprocessing the command means that some checks will be reevaluated once the
      client is unblocked.
      For example, ACL rules might change since the command originally was executed and
      will fail once the client is unblocked.
      Another example is OOM condition checks which might enable the command to run and
      block but fail the command reprocess once the client is unblocked.
      
      3. One of the changes in this PR is that no command stats are being updated once the
      command is blocked (all stats will be updated once the client is unblocked). This implies
      that when we have many clients blocked, users will no longer be able to get that information
      from the command stats. However the information can still be gathered from the client list.
      
      **Client blocking**
      ---------------------------------------------------
      
      the blocking on key will still be triggered the same way as it is done today.
      in order to block the current client on list of keys, the call to
      blockForKeys will still need to be made which will perform the same as it is today:
      
      *  add the client to the list of blocked clients on each key
      *  keep the key with a matching list node (position in the global blocking clients list for that key)
         in the client private blocking key dict.
      *  flag the client with CLIENT_BLOCKED
      *  update blocking statistics
      *  register the client on the timeout table
      
      **Key Unblock**
      ---------------------------------------------------
      
      Unblocking a specific key will be triggered (same as today) by calling signalKeyAsReady.
      the implementation in that part will stay the same as today - adding the key to the global readyList.
      The reason to maintain the readyList (as apposed to iterating over all clients blocked on the specific key)
      is in order to keep the signal operation as short as possible, since it is called during the command processing.
      The main change is that instead of going through a dedicated code path that operates the blocked command
      we will just call processPendingCommandsAndResetClient.
      
      **ClientUnblock (keys)**
      ---------------------------------------------------
      
      1. Unblocking clients on keys will be triggered after command is
         processed and during the beforeSleep
      8. the general schema is:
      9. For each key *k* in the readyList:
      ```            
      For each client *c* which is blocked on *k*:
                  in case either:
      	          1. *k* exists AND the *k* type matches the current client blocking type
      	  	      OR
      	          2. *k* exists and *c* is blocked on module command
      	    	      OR
      	          3. *k* does not exists and *c* was blocked with the flag
      	             unblock_on_deleted_key
                       do:
                                        1. remove the client from the list of clients blocked on this key
                                        2. remove the blocking list node from the client blocking key dict
                                        3. remove the client from the timeout list
                                        10. queue the client on the unblocked_clients list
                                        11. *NEW*: call processCommandAndResetClient(c);
      ```
      *NOTE:* for module blocked clients we will still call the moduleUnblockClientByHandle
                    which will queue the client for processing in moduleUnblockedClients list.
      
      **Process Unblocked clients**
      ---------------------------------------------------
      
      The process of all unblocked clients is done in the beforeSleep and no change is planned
      in that part.
      
      The general schema will be:
      For each client *c* in server.unblocked_clients:
      
              * remove client from the server.unblocked_clients
              * set back the client readHandler
              * continue processing the pending command and input buffer.
      
      *Some notes regarding the new implementation*
      ---------------------------------------------------
      
      1. Although it was proposed, it is currently difficult to remove the
         read handler from the client while it is blocked.
         The reason is that a blocked client should be unblocked when it is
         disconnected, or we might consume data into void.
      
      2. While this PR mainly keep the current blocking logic as-is, there
         might be some future additions to the infrastructure that we would
         like to have:
         - allow non-preemptive blocking of client - sometimes we can think
           that a new kind of blocking can be expected to not be preempt. for
           example lets imagine we hold some keys on disk and when a command
           needs to process them it will block until the keys are uploaded.
           in this case we will want the client to not disconnect or be
           unblocked until the process is completed (remove the client read
           handler, prevent client timeout, disable unblock via debug command etc...).
         - allow generic blocking based on command declared keys - we might
           want to add a hook before command processing to check if any of the
           declared keys require the command to block. this way it would be
           easier to add new kinds of key-based blocking mechanisms.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Signed-off-by: default avatarRan Shidlansik <ranshid@amazon.com>
      383d902c
  16. 20 Dec, 2022 1 commit
    • guybe7's avatar
      Cleanup: Get rid of server.core_propagates (#11572) · 9c7c6924
      guybe7 authored
      1. Get rid of server.core_propagates - we can just rely on module/call nesting levels
      2. Rename in_nested_call  to execution_nesting and update the comment
      3. Remove module_ctx_nesting (redundant, we can use execution_nesting)
      4. Modify postExecutionUnitOperations according to the comment (The main purpose of this PR)
      5. trackingHandlePendingKeyInvalidations: Check the nesting level inside this function
      9c7c6924
  17. 09 Dec, 2022 1 commit
    • Binbin's avatar
      Fix zuiFind crash / RM_ScanKey hang on SET object listpack encoding (#11581) · 20854cb6
      Binbin authored
      
      
      In #11290, we added listpack encoding for SET object.
      But forgot to support it in zuiFind, causes ZINTER, ZINTERSTORE,
      ZINTERCARD, ZIDFF, ZDIFFSTORE to crash.
      And forgot to support it in RM_ScanKey, causes it hang.
      
      This PR add support SET listpack in zuiFind, and in RM_ScanKey.
      And add tests for related commands to cover this case.
      
      Other changes:
      - There is no reason for zuiFind to go into the internals of the SET.
        It can simply use setTypeIsMember and don't care about encoding.
      - Remove the `#include "intset.h"` from server.h reduce the chance of
        accidental intset API use.
      - Move setTypeAddAux, setTypeRemoveAux and setTypeIsMemberAux
        interfaces to the header.
      - In scanGenericCommand, use setTypeInitIterator and setTypeNext
        to handle OBJ_SET scan.
      - In RM_ScanKey, improve hash scan mode, use lpGetValue like zset,
        they can share code and better performance.
      
      The zuiFind part fixes #11578
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarViktor Söderqvist <viktor.soderqvist@est.tech>
      20854cb6
  18. 08 Dec, 2022 1 commit
  19. 30 Nov, 2022 1 commit
    • Huang Zhw's avatar
      Add a special notification unlink available only for modules (#9406) · c8181314
      Huang Zhw authored
      
      
      Add a new module event `RedisModule_Event_Key`, this event is fired
      when a key is removed from the keyspace.
      The event includes an open key that can be used for reading the key before
      it is removed. Modules can also extract the key-name, and use RM_Open
      or RM_Call to access key from within that event, but shouldn't modify anything
      from within this event.
      
      The following sub events are available:
        - `REDISMODULE_SUBEVENT_KEY_DELETED`
        - `REDISMODULE_SUBEVENT_KEY_EXPIRED`
        - `REDISMODULE_SUBEVENT_KEY_EVICTED`
        - `REDISMODULE_SUBEVENT_KEY_OVERWRITE`
      
      The data pointer can be casted to a RedisModuleKeyInfo structure
      with the following fields:
      ```
           RedisModuleKey *key;    // Opened Key
       ```
      
      ### internals
      
      * We also add two dict functions:
        `dictTwoPhaseUnlinkFind` finds an element from the table, also get the plink of the entry.
        The entry is returned if the element is found. The user should later call `dictTwoPhaseUnlinkFree`
        with it in order to unlink and release it. Otherwise if the key is not found, NULL is returned.
        These two functions should be used in pair. `dictTwoPhaseUnlinkFind` pauses rehash and
        `dictTwoPhaseUnlinkFree` resumes rehash.
      * We change `dbOverwrite` to `dbReplaceValue` which just replaces the value of the key and
        doesn't fire any events. The "overwrite" part (which emits events) is just when called from `setKey`,
        the other places that called dbOverwrite were ones that just update the value in-place (INCR*, SPOP,
        and dbUnshareStringValue). This should not have any real impact since `moduleNotifyKeyUnlink` and
        `signalDeletedKeyAsReady` wouldn't have mattered in these cases anyway (i.e. module keys and
        stream keys didn't have direct calls to dbOverwrite)
      * since we allow doing RM_OpenKey from withing these callbacks, we temporarily disable lazy expiry.
      * We also temporarily disable lazy expiry when we are in unlink/unlink2 callback and keyspace 
        notification callback.
      * Move special definitions to the top of redismodule.h
        This is needed to resolve compilation errors with RedisModuleKeyInfoV1
        that carries a RedisModuleKey member.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      c8181314
  20. 24 Nov, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Module API to allow writes after key space notification hooks (#11199) · abc345ad
      Meir Shpilraien (Spielrein) authored
      ### Summary of API additions
      
      * `RedisModule_AddPostNotificationJob` - new API to call inside a key space
        notification (and on more locations in the future) and allow to add a post job as describe above.
      * New module option, `REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS`,
        allows to disable Redis protection of nested key-space notifications.
      * `RedisModule_GetModuleOptionsAll` - gets the mask of all supported module options so a module
        will be able to check if a given option is supported by the current running Redis instance.
      
      ### Background
      
      The following PR is a proposal of handling write operations inside module key space notifications.
      After a lot of discussions we came to a conclusion that module should not perform any write
      operations on key space notification.
      
      Some examples of issues that such write operation can cause are describe on the following links:
      
      * Bad replication oreder - https://github.com/redis/redis/pull/10969
      * Used after free - https://github.com/redis/redis/pull/10969#issuecomment-1223771006
      * Used after free - https://github.com/redis/redis/pull/9406#issuecomment-1221684054
      
      
      
      There are probably more issues that are yet to be discovered. The underline problem with writing
      inside key space notification is that the notification runs synchronously, this means that the notification
      code will be executed in the middle on Redis logic (commands logic, eviction, expire).
      Redis **do not assume** that the data might change while running the logic and such changes
      can crash Redis or cause unexpected behaviour.
      
      The solution is to state that modules **should not** perform any write command inside key space
      notification (we can chose whether or not we want to force it). To still cover the use-case where
      module wants to perform a write operation as a reaction to key space notifications, we introduce
      a new API , `RedisModule_AddPostNotificationJob`, that allows to register a callback that will be
      called by Redis when the following conditions hold:
      
      * It is safe to perform any write operation.
      * The job will be called atomically along side the operation that triggers it (in our case, key
        space notification).
      
      Module can use this new API to safely perform any write operation and still achieve atomicity
      between the notification and the write.
      
      Although currently the API is supported on key space notifications, the API is written in a generic
      way so that in the future we will be able to use it on other places (server events for example).
      
      ### Technical Details
      
      Whenever a module uses `RedisModule_AddPostNotificationJob` the callback is added to a list
      of callbacks (called `modulePostExecUnitJobs`) that need to be invoke after the current execution
      unit ends (whether its a command, eviction, or active expire). In order to trigger those callback
      atomically with the notification effect, we call those callbacks on `postExecutionUnitOperations`
      (which was `propagatePendingCommands` before this PR). The new function fires the post jobs
      and then calls `propagatePendingCommands`.
      
      If the callback perform more operations that triggers more key space notifications. Those keys
      space notifications might register more callbacks. Those callbacks will be added to the end
      of `modulePostExecUnitJobs` list and will be invoke atomically after the current callback ends.
      This raises a concerns of entering an infinite loops, we consider infinite loops as a logical bug
      that need to be fixed in the module, an attempt to protect against infinite loops by halting the
      execution could result in violation of the feature correctness and so **Redis will make no attempt
      to protect the module from infinite loops**
      
      In addition, currently key space notifications are not nested. Some modules might want to allow
      nesting key-space notifications. To allow that and keep backward compatibility, we introduce a
      new module option called `REDISMODULE_OPTIONS_ALLOW_NESTED_KEYSPACE_NOTIFICATIONS`.
      Setting this option will disable the Redis key-space notifications nesting protection and will
      pass this responsibility to the module.
      
      ### Redis infrastructure
      
      This PR promotes the existing `propagatePendingCommands` to an "Execution Unit" concept,
      which is called after each atomic unit of execution,
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarYossi Gottlieb <yossigo@gmail.com>
      Co-authored-by: default avatarMadelyn Olson <34459052+madolson@users.noreply.github.com>
      abc345ad
  21. 16 Nov, 2022 1 commit
    • sundb's avatar
      Add listpack encoding for list (#11303) · 2168ccc6
      sundb authored
      Improve memory efficiency of list keys
      
      ## Description of the feature
      The new listpack encoding uses the old `list-max-listpack-size` config
      to perform the conversion, which we can think it of as a node inside a
      quicklist, but without 80 bytes overhead (internal fragmentation included)
      of quicklist and quicklistNode structs.
      For example, a list key with 5 items of 10 chars each, now takes 128 bytes
      instead of 208 it used to take.
      
      ## Conversion rules
      * Convert listpack to quicklist
        When the listpack length or size reaches the `list-max-listpack-size` limit,
        it will be converted to a quicklist.
      * Convert quicklist to listpack
        When a quicklist has only one node, and its length or size is reduced to half
        of the `list-max-listpack-size` limit, it will be converted to a listpack.
        This is done to avoid frequent conversions when we add or remove at the bounding size or length.
          
      ## Interface changes
      1. add list entry param to listTypeSetIteratorDirection
          When list encoding is listpack, `listTypeIterator->lpi` points to the next entry of current entry,
          so when changing the direction, we need to use the current node (listTypeEntry->p) to 
          update `listTypeIterator->lpi` to the next node in the reverse direction.
      
      ## Benchmark
      ### Listpack VS Quicklist with one node
      * LPUSH - roughly 0.3% improvement
      * LRANGE - roughly 13% improvement
      
      ### Both are quicklist
      * LRANGE - roughly 3% improvement
      * LRANGE without pipeline - roughly 3% improvement
      
      From the benchmark, as we can see from the results
      1. When list is quicklist encoding, LRANGE improves performance by <5%.
      2. When list is listpack encoding, LRANGE improves performance by ~13%,
         the main enhancement is brought by `addListListpackRangeReply()`.
      
      ## Memory usage
      1M lists(key:0~key:1000000) with 5 items of 10 chars ("hellohello") each.
      shows memory usage down by 35.49%, from 214MB to 138MB.
      
      ## Note
      1. Add conversion callback to support doing some work before conversion
          Since the quicklist iterator decompresses the current node when it is released, we can 
          no longer decompress the quicklist after we convert the list.
      2168ccc6
  22. 14 Nov, 2022 1 commit
  23. 03 Nov, 2022 1 commit
    • Binbin's avatar
      Block some specific characters in module command names (#11434) · 8764611c
      Binbin authored
      Today we don't place any specific restrictions on module command names.
      This can cause ambiguous scenarios. For example, someone might name a
      command like "module|feature" which would be incorrectly parsed by the
      ACL system as a subcommand.
      
      In this PR, we will block some chars that we know can mess things up.
      Specifically ones that can appear ok at first and cause problems in some
      cases (we rather surface the issue right away).
      
      There are these characters:
       * ` ` (space) - issues with old inline protocol.
       * `\r`, `\n` (newline) - can mess up the protocol on acl error replies.
       * `|` - sub-commands.
       * `@` - ACL categories
       * `=`, `,` - info and client list fields.
      
      note that we decided to leave `:` out as it's handled by `getSafeInfoString`
      and is more likely to already been used by existing modules.
      8764611c
  24. 27 Oct, 2022 2 commits
    • Moti Cohen's avatar
      Refactor and (internally) rebrand from pause-clients to pause-actions (#11098) · c0d72262
      Moti Cohen authored
      Renamed from "Pause Clients" to "Pause Actions" since the mechanism can pause
      several actions in redis, not just clients (e.g. eviction, expiration).
      
      Previously each pause purpose (which has a timeout that's tracked separately from others purposes),
      also implicitly dictated what it pauses (reads, writes, eviction, etc). Now it is explicit, and
      the actions that are paused (bit flags) are defined separately from the purpose.
      
      - Previously, when using feature pause-client it also implicitly means to make the server static:
        - Pause replica traffic
        - Pauses eviction processing
        - Pauses expire processing
      
      Making the server static is used also for failover and shutdown. This PR internally rebrand
      pause-client API to become pause-action API. It also Simplifies pauseClients structure
      by replacing pointers array with static array.
      
      The context of this PR is to add another trigger to pause-client which will activated in case
      of OOM as throttling mechanism ([see here](https://github.com/redis/redis/issues/10907)).
      In this case we want only to pause client, and eviction actions.
      c0d72262
    • Shaya Potter's avatar
      RM_Call - only enforce OOM on scripts if 'M' flag is sent (#11425) · 38028dab
      Shaya Potter authored
      
      
      RM_Call is designed to let modules call redis commands disregarding the
      OOM state (the module is responsible to declare its command flags to redis,
      or perform the necessary checks).
      The other (new) alternative is to pass the "M" flag to RM_Call so that redis can
      OOM reject commands implicitly.
      
      However, Currently, RM_Call enforces OOM on scripts (excluding scripts that
      declared `allow-oom`) in all cases, regardless of the RM_Call "M" flag being present.
      
      This PR fixes scripts to be consistent with other commands being executed by RM_Call.
      It modifies the flow in effect treats scripts as if they if they have the ALLOW_OOM script
      flag, if the "M" flag is not passed (i.e. no OOM checking is being performed by RM_Call,
      so no OOM checking should be done on script).
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      38028dab
  25. 24 Oct, 2022 1 commit
  26. 22 Oct, 2022 1 commit
    • sundb's avatar
      Fix crash due to to reuse iterator entry after list deletion in module (#11383) · 6dd21355
      sundb authored
      
      
      In the module, we will reuse the list iterator entry for RM_ListDelete, but `listTypeDelete` will only update
      `quicklistEntry->zi` but not `quicklistEntry->node`, which will result in `quicklistEntry->node` pointing to
      a freed memory address if the quicklist node is deleted. 
      
      This PR sync `key->u.list.index` and `key->u.list.entry` to list iterator after `RM_ListDelete`.
      
      This PR also optimizes the release code of the original list iterator.
      Co-authored-by: default avatarViktor Söderqvist <viktor@zuiderkwast.se>
      6dd21355
  27. 18 Oct, 2022 2 commits
    • guybe7's avatar
      Blocked module clients should be aware when a key is deleted (#11310) · b57fd010
      guybe7 authored
      The use case is a module that wants to implement a blocking command on a key that
      necessarily exists and wants to unblock the client in case the key is deleted (much like
      what we implemented for XREADGROUP in #10306)
      
      New module API:
      * RedisModule_BlockClientOnKeysWithFlags
      
      Flags:
      * REDISMODULE_BLOCK_UNBLOCK_NONE
      * REDISMODULE_BLOCK_UNBLOCK_DELETED
      
      ### Detailed description of code changes
      
      blocked.c:
      1. Both module and stream functions are called whether the key exists or not, regardless of
        its type. We do that in order to allow modules/stream to unblock the client in case the key
        is no longer present or has changed type (the behavior for streams didn't change, just code
        that moved into serveClientsBlockedOnStreamKey)
      2. Make sure afterCommand is called in serveClientsBlockedOnKeyByModule, in order to propagate
        actions from moduleTryServeClientBlockedOnKey.
      3. handleClientsBlockedOnKeys: call propagatePendingCommands directly after lookupKeyReadWithFlags
        to prevent a possible lazy-expire DEL from being mixed with any command propagated by the
        preceding functions.
      4. blockForKeys: Caller can specifiy that it wants to be awakened if key is deleted.
         Minor optimizations (use dictAddRaw).
      5. signalKeyAsReady became signalKeyAsReadyLogic which can take a boolean in case the key is deleted.
        It will only signal if there's at least one client that awaits key deletion (to save calls to
        handleClientsBlockedOnKeys).
        Minor optimizations (use dictAddRaw)
      
      db.c:
      1. scanDatabaseForDeletedStreams is now scanDatabaseForDeletedKeys and will signalKeyAsReady
        for any key that was removed from the database or changed type. It is the responsibility of the code
        in blocked.c to ignore or act on deleted/type-changed keys.
      2. Use the new signalDeletedKeyAsReady where needed
      
      blockedonkey.c + tcl:
      1. Added test of new capabilities (FSL.BPOPGT now requires the key to exist in order to work)
      b57fd010
    • Meir Shpilraien (Spielrein)'s avatar
      Avoid saving module aux on RDB if no aux data was saved by the module. (#11374) · b43f2548
      Meir Shpilraien (Spielrein) authored
      ### Background
      
      The issue is that when saving an RDB with module AUX data, the module AUX metadata
      (moduleid, when, ...) is saved to the RDB even though the module did not saved any actual data.
      This prevent loading the RDB in the absence of the module (although there is no actual data in
      the RDB that requires the module to be loaded).
      
      ### Solution
      
      The solution suggested in this PR is that module AUX will be saved on the RDB only if the module
      actually saved something during `aux_save` function.
      
      To support backward compatibility, we introduce `aux_save2` callback that acts the same as
      `aux_save` with the tiny change of avoid saving the aux field if no data was actually saved by
      the module. Modules can use the new API to make sure that if they have no data to save,
      then it will be possible to load the created RDB even without the module.
      
      ### Concerns
      
      A module may register for the aux load and save hooks just in order to be notified when
      saving or loading starts or completed (there are better ways to do that, but it still possible
      that someone used it).
      
      However, if a module didn't save a single field in the save callback, it means it's not allowed
      to read in the read callback, since it has no way to distinguish between empty and non-empty
      payloads. furthermore, it means that if the module did that, it must never change it, since it'll
      break compatibility with it's old RDB files, so this is really not a valid use case.
      
      Since some modules (ones who currently save one field indicating an empty payload), need
      to know if saving an empty payload is valid, and if Redis is gonna ignore an empty payload
      or store it, we opted to add a new API (rather than change behavior of an existing API and
      expect modules to check the redis version)
      
      ### Technical Details
      
      To avoid saving AUX data on RDB, we change the code to first save the AUX metadata
      (moduleid, when, ...) into a temporary buffer. The buffer is then flushed to the rio at the first
      time the module makes a write operation inside the `aux_save` function. If the module saves
      nothing (and `aux_save2` was used), the entire temporary buffer is simply dropped and no
      data about this AUX field is saved to the RDB. This make it possible to load the RDB even in
      the absence of the module.
      
      Test was added to verify the fix.
      b43f2548
  28. 16 Oct, 2022 1 commit
    • Shaya Potter's avatar
      Unify ACL failure error messaging. (#11160) · 3193f086
      Shaya Potter authored
      Motivation: for applications that use RM ACL verification functions, they would
      want to return errors back to the user, in ways that are consistent with Redis.
      While investigating how we should return ACL errors to the user, we realized that
      Redis isn't consistent, and currently returns ACL error strings in 3 primary ways.
      
      [For the actual implications of this change, see the "Impact" section at the bottom]
      
      1. how it returns an error when calling a command normally
         ACL_DENIED_CMD -> "this user has no permissions to run the '%s' command"
         ACL_DENIED_KEY -> "this user has no permissions to access one of the keys used as arguments"
         ACL_DENIED_CHANNEL -> "this user has no permissions to access one of the channels used as arguments"
      
      2. how it returns an error when calling via 'acl dryrun' command
         ACL_DENIED_CMD ->  "This user has no permissions to run the '%s' command"
         ACL_DENIED_KEY -> "This user has no permissions to access the '%s' key"
         ACL_DENIED_CHANNEL -> "This user has no permissions to access the '%s' channel"
      
      3. how it returns an error via RM_Call (and scripting is similar).
         ACL_DENIED_CMD -> "can't run this command or subcommand";
         ACL_DENIED_KEY -> "can't access at least one of the keys mentioned in the command arguments";
         ACL_DENIED_CHANNEL -> "can't publish to the channel mentioned in the command";
         
         In addition, if one wants to use RM_Call's "dry run" capability instead of the RM ACL
         functions directly, one also sees a different problem than it returns ACL errors with a -ERR,
         not a -PERM, so it can't be returned directly to the caller.
      
      This PR modifies the code to generate a base message in a common manner with the ability
      to set verbose flag for acl dry run errors, and keep it unset for normal/rm_call/script cases
      
      ```c
      sds getAclErrorMessage(int acl_res, user *user, struct redisCommand *cmd, sds errored_val, int verbose) {
          switch (acl_res) {
          case ACL_DENIED_CMD:
              return sdscatfmt(sdsempty(), "User %S has no permissions to run "
                                           "the '%S' command", user->name, cmd->fullname);
          case ACL_DENIED_KEY:
              if (verbose) {
                  return sdscatfmt(sdsempty(), "User %S has no permissions to access "
                                               "the '%S' key", user->name, errored_val);
              } else {
                  return sdsnew("No permissions to access a key");
              }
          case ACL_DENIED_CHANNEL:
              if (verbose) {
                  return sdscatfmt(sdsempty(), "User %S has no permissions to access "
                                               "the '%S' channel", user->name, errored_val);
              } else {
                  return sdsnew("No permissions to access a channel");
              }
          }
      ```
      
      The caller can append/prepend the message (adding NOPERM for normal/RM_Call or indicating it's within a script).
      
      Impact:
      - Plain commands, as well as scripts and RM_Call now include the user name.
      - ACL DRYRUN remains the only one that's verbose (mentions the offending channel or key name)
      - Changes RM_Call ACL errors from being a `-ERR` to being `-NOPERM` (besides for textual changes)
        **This somewhat a breaking change, but it only affects the RM_Call with both `C` and `E`, or `D`**
      - Changes ACL errors in scripts textually from being
        `The user executing the script <old non unified text>`
        to
        `ACL failure in script: <new unified text>`
      3193f086
  29. 09 Oct, 2022 2 commits
    • Binbin's avatar
      Freeze time sampling during command execution, and scripts (#10300) · 35b3fbd9
      Binbin authored
      Freeze time during execution of scripts and all other commands.
      This means that a key is either expired or not, and doesn't change
      state during a script execution. resolves #10182
      
      This PR try to add a new `commandTimeSnapshot` function.
      The function logic is extracted from `keyIsExpired`, but the related
      calls to `fixed_time_expire` and `mstime()` are removed, see below.
      
      In commands, we will avoid calling `mstime()` multiple times
      and just use the one that sampled in call. The background is,
      e.g. using `PEXPIRE 1` with valgrind sometimes result in the key
      being deleted rather than expired. The reason is that both `PEXPIRE`
      command and `checkAlreadyExpired` call `mstime()` separately.
      
      There are other more important changes in this PR:
      1. Eliminate `fixed_time_expire`, it is no longer needed. 
         When we want to sample time we should always use a time snapshot. 
         We will use `in_nested_call` instead to update the cached time in `call`.
      2. Move the call for `updateCachedTime` from `serverCron` to `afterSleep`.
          Now `commandTimeSnapshot` will always return the sample time, the
          `lookupKeyReadWithFlags` call in `getNodeByQuery` will get a outdated
          cached time (because `processCommand` is out of the `call` context).
          We put the call to `updateCachedTime` in `aftersleep`.
      3. Cache the time each time the module lock Redis.
          Call `updateCachedTime` in `moduleGILAfterLock`, affecting `RM_ThreadSafeContextLock`
          and `RM_ThreadSafeContextTryLock`
      
      Currently the commandTimeSnapshot change affects the following TTL commands:
      - SET EX / SET PX
      - EXPIRE / PEXPIRE
      - SETEX / PSETEX
      - GETEX EX / GETEX PX
      - TTL / PTTL
      - EXPIRETIME / PEXPIRETIME
      - RESTORE key TTL
      
      And other commands just use the cached mstime (including TIME).
      
      This is considered to be a breaking change since it can break a script
      that uses a loop to wait for a key to expire.
      35b3fbd9
    • Meir Shpilraien (Spielrein)'s avatar
      `RedisModule_ResetDataset` should not clear the functions. (#11268) · d2ad01ab
      Meir Shpilraien (Spielrein) authored
      As mentioned on docs, `RM_ResetDataset` Performs similar operation to FLUSHALL.
      As FLUSHALL do not clean the function, `RM_ResetDataset` should not clean the functions
      as well.
      d2ad01ab
  30. 28 Sep, 2022 1 commit
    • guybe7's avatar
      RM_CreateCommand should not set CMD_KEY_VARIABLE_FLAGS automatically (#11320) · 3330ea18
      guybe7 authored
      The original idea behind auto-setting the default (first,last,step) spec was to use
      the most "open" flags when the user didn't provide any key-spec flags information.
      
      While the above idea is a good approach, it really makes no sense to set
      CMD_KEY_VARIABLE_FLAGS if the user didn't provide the getkeys-api flag:
      in this case there's not way to retrieve these variable flags, so what's the point?
      
      Internally in redis there was code to ignore this already, so this fix doesn't change
      redis's behavior, it only affects the output of COMMAND command.
      3330ea18
  31. 26 Sep, 2022 1 commit
    • Ozan Tezcan's avatar
      Ignore RM_Call deny-oom flag if maxmemory is zero (#11319) · 18920813
      Ozan Tezcan authored
      If a command gets an OOM response and then if we set maxmemory to zero
      to disable the limit, server.pre_command_oom_state never gets updated
      and it stays true. As RM_Call() calls with "respect deny-oom" flag checks
      server.pre_command_oom_state, all calls will fail with OOM.
      
      Added server.maxmemory check in RM_Call() to process deny-oom flag
      only if maxmemory is configured.
      18920813
  32. 22 Sep, 2022 1 commit
    • Shaya Potter's avatar
      Add RM_SetContextUser to support acl validation in RM_Call (and scripts) (#10966) · 6e993a5d
      Shaya Potter authored
      Adds a number of user management/ACL validaiton/command execution functions to improve a
      Redis module's ability to enforce ACLs correctly and easily.
      
      * RM_SetContextUser - sets a RedisModuleUser on the context, which RM_Call will use to both
        validate ACLs (if requested and set) as well as assign to the client so that scripts executed via
        RM_Call will have proper ACL validation.
      * RM_SetModuleUserACLString - Enables one to pass an entire ACL string, not just a single OP
        and have it applied to the user
      * RM_GetModuleUserACLString - returns a stringified version of the user's ACL (same format as dump
        and list).  Contains an optimization to cache the stringified version until the underlying ACL is modified.
      * Slightly re-purpose the "C" flag to RM_Call from just being about ACL check before calling the
        command, to actually running the command with the right user, so that it also affects commands
        inside EVAL scripts. see #11231
      6e993a5d
  33. 15 Sep, 2022 1 commit
  34. 05 Sep, 2022 1 commit
    • Shaya Potter's avatar
      Add a dry run flag to RM_Call execution (#11158) · 87e7973c
      Shaya Potter authored
      Add a new "D" flag to RM_Call which runs whatever verification the user requests,
      but returns before the actual execution of the command.
      
      It automatically enables returning error messages as CallReply objects to distinguish
      success (NULL) from failure (CallReply returned).
      87e7973c