1. 22 Mar, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Add new RM_Call flags for script mode, no writes, and error replies. (#10372) · f3855a09
      Meir Shpilraien (Spielrein) authored
      The PR extends RM_Call with 3 new capabilities using new flags that
      are given to RM_Call as part of the `fmt` argument.
      It aims to assist modules that are getting a list of commands to be
      executed from the user (not hard coded as part of the module logic),
      think of a module that implements a new scripting language...
      
      * `S` - Run the command in a script mode, this means that it will raise an
        error if a command which are not allowed inside a script (flaged with the
        `deny-script` flag) is invoked (like SHUTDOWN). In addition, on script mode,
        write commands are not allowed if there is not enough good replicas (as
        configured with `min-replicas-to-write`) and/or a disk error happened.
      
      * `W` - no writes mode, Redis will reject any command that is marked with `write`
        flag. Again can be useful to modules that implement a new scripting language
        and wants to prevent any write commands.
      
      * `E` - Return errors as RedisModuleCallReply. Today the errors that happened
        before the command was invoked (like unknown commands or acl error) return
        a NULL reply and set errno. This might be missing important information about
        the failure and it is also impossible to just pass the error to the user using
        RM_ReplyWithCallReply. This new flag allows you to get a RedisModuleCallReply
        object with the relevant error message and treat it as if it was an error that was
        raised by the command invocation.
      
      Tests were added to verify the new code paths.
      
      In addition small refactoring was done to share some code between modules,
      scripts, and `processCommand` function:
      1. `getAclErrorMessage` was added to `acl.c` to unified to log message extraction
        from the acl result
      2. `checkGoodReplicasStatus` was added to `replication.c` to check the status of
        good replicas. It is used on `scriptVerifyWriteCommandAllow`, `RM_Call`, and
        `processCommand`.
      3. `writeCommandsGetDiskErrorMessage` was added to `server.c` to get the error
        message on persistence failure. Again it is used on `scriptVerifyWriteCommandAllow`,
        `RM_Call`, and `processCommand`.
      f3855a09
  2. 16 Mar, 2022 1 commit
  3. 08 Mar, 2022 1 commit
    • guybe7's avatar
      XREADGROUP: Unblock client if stream is deleted (#10306) · 2a295408
      guybe7 authored
      Deleting a stream while a client is blocked XREADGROUP should unblock the client.
      
      The idea is that if a client is blocked via XREADGROUP is different from
      any other blocking type in the sense that it depends on the existence of both
      the key and the group. Even if the key is deleted and then revived with XADD
      it won't help any clients blocked on XREADGROUP because the group no longer
      exist, so they would fail with -NOGROUP anyway.
      The conclusion is that it's better to unblock these clients (with error) upon
      the deletion of the key, rather than waiting for the first XADD. 
      
      Other changes:
      1. Slightly optimize all `serveClientsBlockedOn*` functions by checking `server.blocked_clients_by_type`
      2. All `serveClientsBlockedOn*` functions now use a list iterator rather than looking at `listFirst`, relying
        on `unblockClient` to delete the head of the list. Before this commit, only `serveClientsBlockedOnStreams`
        used to work like that.
      3. bugfix: CLIENT UNBLOCK ERROR should work even if the command doesn't have a timeout_callback
        (only relevant to module commands)
      2a295408
  4. 07 Mar, 2022 1 commit
  5. 22 Feb, 2022 1 commit
    • Madelyn Olson's avatar
      Implemented module getchannels api and renamed channel keyspec (#10299) · 71204f96
      Madelyn Olson authored
      This implements the following main pieces of functionality:
      * Renames key spec "CHANNEL" to be "NOT_KEY", and update the documentation to
        indicate it's for cluster routing and not for any other key related purpose.
      * Add the getchannels-api, so that modules can now define commands that are subject to
        ACL channel permission checks. 
      * Add 4 new flags that describe how a module interacts with a command (SUBSCRIBE, PUBLISH,
        UNSUBSCRIBE, and PATTERN). They are all technically composable, however not sure how a
        command could both subscribe and unsubscribe from a command at once, but didn't see
        a reason to add explicit validation there.
      * Add two new module apis RM_ChannelAtPosWithFlags and RM_IsChannelsPositionRequest to
        duplicate the functionality provided by the keys position APIs.
      * The RM_ACLCheckChannelPermissions (only released in 7.0 RC1) was changed to take flags
        rather than a boolean literal.
      * The RM_ACLCheckKeyPermissions (only released in 7.0 RC1) was changed to take flags
        corresponding to keyspecs instead of custom permission flags. These keyspec flags mimic
        the flags for ACLCheckChannelPermissions.
      71204f96
  6. 08 Feb, 2022 1 commit
    • Oran Agra's avatar
      Handle key-spec flags with modules (#10237) · 66be30f7
      Oran Agra authored
      - add COMMAND GETKEYSANDFLAGS sub-command
      - add RM_KeyAtPosWithFlags and GetCommandKeysWithFlags
      - RM_KeyAtPos and RM_CreateCommand set flags requiring full access for keys
      - RM_CreateCommand set VARIABLE_FLAGS
      - expose `variable_flags` flag in COMMAND INFO key-specs
      - getKeysFromCommandWithSpecs prefers key-specs over getkeys-api
      - add tests for all of these
      66be30f7
  7. 04 Feb, 2022 1 commit
    • Viktor Söderqvist's avatar
      Command info module API (#10108) · 0a82fe84
      Viktor Söderqvist authored
      Adds RM_SetCommandInfo, allowing modules to provide the following command info:
      
      * summary
      * complexity
      * since
      * history
      * hints
      * arity
      * key specs
      * args
      
      This information affects the output of `COMMAND`, `COMMAND INFO` and `COMMAND DOCS`,
      Cluster, ACL and is used to filter commands with the wrong number of arguments before
      the call reaches the module code.
      
      The recently added API functions for key specs (never released) are removed.
      
      A minimalist example would look like so:
      ```c
          RedisModuleCommand *mycmd = RedisModule_GetCommand(ctx,"mymodule.mycommand");
          RedisModuleCommandInfo mycmd_info = {
              .version = REDISMODULE_COMMAND_INFO_VERSION,
              .arity = -5,
              .summary = "some description",
          };
          if (RedisModule_SetCommandInfo(mycmd, &mycmd_info) == REDISMODULE_ERR)
              return REDISMODULE_ERR;
      ````
      
      Notes:
      * All the provided information (including strings) is copied, not keeping references to the API input data.
      * The version field is actually a static struct that contains the sizes of the the structs used in arrays,
        so we can extend these in the future and old version will still be able to take the part they can support.
      0a82fe84
  8. 26 Jan, 2022 1 commit
  9. 24 Jan, 2022 1 commit
  10. 23 Jan, 2022 1 commit
    • Binbin's avatar
      sub-command support for ACL CAT and COMMAND LIST. redisCommand always stores fullname (#10127) · 23325c13
      Binbin authored
      
      
      Summary of changes:
      1. Rename `redisCommand->name` to `redisCommand->declared_name`, it is a
        const char * for native commands and SDS for module commands.
      2. Store the [sub]command fullname in `redisCommand->fullname` (sds).
      3. List subcommands in `ACL CAT`
      4. List subcommands in `COMMAND LIST`
      5. `moduleUnregisterCommands` now will also free the module subcommands.
      6. RM_GetCurrentCommandName returns full command name
      
      Other changes:
      1. Add `addReplyErrorArity` and `addReplyErrorExpireTime`
      2. Remove `getFullCommandName` function that now is useless.
      3. Some cleanups about `fullname` since now it is SDS.
      4. Delete `populateSingleCommand` function from server.h that is useless.
      5. Added tests to cover this change.
      6. Add some module unload tests and fix the leaks
      7. Make error messages uniform, make sure they always contain the full command
        name and that it's quoted.
      7. Fixes some typos
      
      see the history in #9504, fixes #10124
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarguybe7 <guy.benoish@redislabs.com>
      23325c13
  11. 20 Jan, 2022 2 commits
    • Madelyn Olson's avatar
      ACL V2 - Selectors and key based permissions (#9974) · 55c81f2c
      Madelyn Olson authored
      
      
      * Implemented selectors which provide multiple different sets of permissions to users
      * Implemented key based permissions 
      * Added a new ACL dry-run command to test permissions before execution
      * Updated module APIs to support checking key based permissions
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      55c81f2c
    • perryitay's avatar
      Adding module api for processing commands during busy jobs and allow flagging... · c4b78823
      perryitay authored
      
      Adding module api for processing commands during busy jobs and allow flagging the commands that should be handled at this status (#9963)
      
      Some modules might perform a long-running logic in different stages of Redis lifetime, for example:
      * command execution
      * RDB loading
      * thread safe context
      
      During this long-running logic Redis is not responsive.
      
      This PR offers 
      1. An API to process events while a busy command is running (`RM_Yield`)
      2. A new flag (`ALLOW_BUSY`) to mark the commands that should be handled during busy
        jobs which can also be used by modules (`allow-busy`)
      3. In slow commands and thread safe contexts, this flag will start rejecting commands with -BUSY only
        after `busy-reply-threshold`
      4. During loading (`rdb_load` callback), it'll process events right away (not wait for `busy-reply-threshold`),
        but either way, the processing is throttled to the server hz rate.
      5. Allow modules to Yield to redis background tasks, but not to client commands
      
      * rename `script-time-limit` to `busy-reply-threshold` (an alias to the pre-7.0 `lua-time-limit`)
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      c4b78823
  12. 18 Jan, 2022 3 commits
    • Oran Agra's avatar
      New detailed key-spec flags (RO, RW, OW, RM, ACCESS, UPDATE, INSERT, DELETE) (#10122) · eef9c6b0
      Oran Agra authored
      The new ACL key based permissions in #9974 require the key-specs (#8324) to have more
      explicit flags rather than just READ and WRITE. See discussion in #10040
      
      This PR defines two groups of flags:
      One about how redis internally handles the key (mutually-exclusive).
      The other is about the logical operation done from the user's point of view (3 mutually exclusive
      write flags, and one read flag, all optional).
      In both groups, if we can't explicitly flag something as explicit read-only, delete-only, or
      insert-only, we flag it as `RW` or `UPDATE`.
      here's the definition from the code:
      ```
      /* Key-spec flags *
       * -------------- */
      /* The following refer what the command actually does with the value or metadata
       * of the key, and not necessarily the user data or how it affects it.
       * Each key-spec may must have exaclty one of these. Any operation that's not
       * distinctly deletion, overwrite or read-only would be marked as RW. */
      #define CMD_KEY_RO (1ULL<<0)     /* Read-Only - Reads the value of the key, but
                                        * doesn't necessarily returns it. */
      #define CMD_KEY_RW (1ULL<<1)     /* Read-Write - Modifies the data stored in the
                                        * value of the key or its metadata. */
      #define CMD_KEY_OW (1ULL<<2)     /* Overwrite - Overwrites the data stored in
                                        * the value of the key. */
      #define CMD_KEY_RM (1ULL<<3)     /* Deletes the key. */
      /* The follwing refer to user data inside the value of the key, not the metadata
       * like LRU, type, cardinality. It refers to the logical operation on the user's
       * data (actual input strings / TTL), being used / returned / copied / changed,
       * It doesn't refer to modification or returning of metadata (like type, count,
       * presence of data). Any write that's not INSERT or DELETE, would be an UPADTE.
       * Each key-spec may have one of the writes with or without access, or none: */
      #define CMD_KEY_ACCESS (1ULL<<4) /* Returns, copies or uses the user data from
                                        * the value of the key. */
      #define CMD_KEY_UPDATE (1ULL<<5) /* Updates data to the value, new value may
                                        * depend on the old value. */
      #define CMD_KEY_INSERT (1ULL<<6) /* Adds data to the value with no chance of,
                                        * modification or deletion of existing data. */
      #define CMD_KEY_DELETE (1ULL<<7) /* Explicitly deletes some content
                                        * from the value of the key. */
      ```
      
      Unrelated changes:
      - generate-command-code.py is only compatible with python3 (modified the shabang)
      - generate-command-code.py print file on json parsing error
      - rename `shard_channel` key-spec flag to just `channel`.
      - add INCOMPLETE flag in input spec of SORT and SORT_RO
      eef9c6b0
    • Wang Yuan's avatar
      Use const char pointer in redismodule.h as far as possible (#10064) · d697daa7
      Wang Yuan authored
      When I used C++ to develop a redis module. i  used `string.data()` as the second parameter `ele`
      of  `RedisModule_DigestAddStringBuffer`, but there is a warning, since we never change the `ele`,
      i think we should use `const char` for it.
      
      This PR adds const to just a handful of module APIs that required it, all not very widely used.
      The implication is a breaking change in terms of compilation error that's easy to resolve, and no ABI impact.
      The affected APIs are around Digest, Info injection, and Cluster bus messages.
      d697daa7
    • Ozan Tezcan's avatar
      Add event loop support to the module API (#10001) · 99ab4236
      Ozan Tezcan authored
      Modules can now register sockets/pipe to the Redis main thread event loop and do network operations asynchronously. Previously, modules had to maintain an event loop and another thread for asynchronous network operations.
      
      Also, if a module is calling API functions after doing some network operations, it had to synchronize its event loop thread's access with Redis main thread by locking the GIL, causing contention on the lock. After this commit, no synchronization is needed as module can operate in Redis main thread context. So, this commit may improve the performance for some use cases.
      
      Added three functions to the module API:
      
      * RedisModule_EventLoopAdd(int fd, int mask, RedisModuleEventLoopFunc func, void *user_data)
      * RedisModule_EventLoopDel(int fd, int mask)
      * RedisModule_EventLoopAddOneShot(RedisModuleEventLoopOneShotFunc func, void *user_data) - This function can be called from other threads to trigger callback on Redis main thread. Callback will be triggered only once. If Redis main thread is sleeping, this call will wake up the Redis main thread.
      Event loop callbacks are called by Redis main thread after locking the GIL. Inside callbacks, modules can operate as if they are holding the GIL.
      
      Added REDISMODULE_EVENT_EVENTLOOP event with two subevents:
      
      * REDISMODULE_SUBEVENT_EVENTLOOP_BEFORE_SLEEP
      * REDISMODULE_SUBEVENT_EVENTLOOP_AFTER_SLEEP
      
      These events are for modules that want to participate in the before and after sleep action. e.g It might be useful to implement batching : Read data from the network, write all to a file in one go on BEFORE_SLEEP event.
      99ab4236
  13. 13 Jan, 2022 2 commits
    • Ozan Tezcan's avatar
      Added RM_MonotonicMicroseconds() API to provide monotonic time function (#10101) · f41cc870
      Ozan Tezcan authored
      Added RM_MonotonicMicroseconds(). Modules can use monotonic timestamp counter for measurements.
      f41cc870
    • chenyang8094's avatar
      Always create base AOF file when redis start from empty. (#10102) · e9bff797
      chenyang8094 authored
      
      
      Force create a BASE file (use a foreground `rewriteAppendOnlyFile`) when redis starts from an
      empty data set and  `appendonly` is  yes.
      
      The reasoning is that normally, after redis is running for some time, and the AOF has gone though
      a few rewrites, there's always a base rdb file. and the scenario where the base file is missing, is
      kinda rare (happens only at empty startup), so this change normalizes it.
      But more importantly, there are or could be some complex modules that are started with some
      configuration, when they create persistence they write that configuration to RDB AUX fields, so
      that can can always know with which configuration the persistence file they're loading was
      created (could be critical). there is (was) one scenario in which they could load their persisted data,
      and that configuration was missing, and this change fixes it.
      
      Add a new module event: REDISMODULE_SUBEVENT_PERSISTENCE_SYNC_AOF_START, similar to
      REDISMODULE_SUBEVENT_PERSISTENCE_AOF_START which is async.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      e9bff797
  14. 30 Dec, 2021 1 commit
  15. 22 Dec, 2021 1 commit
    • guybe7's avatar
      Sort out mess around propagation and MULTI/EXEC (#9890) · 7ac21307
      guybe7 authored
      The mess:
      Some parts use alsoPropagate for late propagation, others using an immediate one (propagate()),
      causing edge cases, ugly/hacky code, and the tendency for bugs
      
      The basic idea is that all commands are propagated via alsoPropagate (i.e. added to a list) and the
      top-most call() is responsible for going over that list and actually propagating them (and wrapping
      them in MULTI/EXEC if there's more than one command). This is done in the new function,
      propagatePendingCommands.
      
      Callers to propagatePendingCommands:
      1. top-most call() (we want all nested call()s to add to the also_propagate array and just the top-most
         one to propagate them) - via `afterCommand`
      2. handleClientsBlockedOnKeys: it is out of call() context and it may propagate stuff - via `afterCommand`. 
      3. handleClientsBlockedOnKeys edge case: if the looked-up key is already expired, we will propagate the
         expire but will not unblock any client so `afterCommand` isn't called. in that case, we have to propagate
         the deletion explicitly.
      4. cron stuff: active-expire and eviction may also propagate stuff
      5. modules: the module API allows to propagate stuff from just about anywhere (timers, keyspace notifications,
         threads). I could have tried to catch all the out-of-call-context places but it seemed easier to handle it in one
         place: when we free the context. in the spirit of what was done in call(), only the top-most freeing of a module
         context may cause propagation.
      6. modules: when using a thread-safe ctx it's not clear when/if the ctx will be freed. we do know that the module
         must lock the GIL before calling RM_Replicate/RM_Call so we propagate the pending commands when
         releasing the GIL.
      
      A "known limitation", which were actually a bug, was fixed because of this commit (see propagate.tcl):
         When using a mix of RM_Call with `!` and RM_Replicate, the command would propagate out-of-order:
         first all the commands from RM_Call, and then the ones from RM_Replicate
      
      Another thing worth mentioning is that if, in the past, a client would issue a MULTI/EXEC with just one
      write command the server would blindly propagate the MULTI/EXEC too, even though it's redundant.
      not anymore.
      
      This commit renames propagate() to propagateNow() in order to cause conflicts in pending PRs.
      propagatePendingCommands is the only caller of propagateNow, which is now a static, internal helper function.
      
      Optimizations:
      1. alsoPropagate will not add stuff to also_propagate if there's no AOF and replicas
      2. alsoPropagate reallocs also_propagagte exponentially, to save calls to memmove
      
      Bugfixes:
      1. CONFIG SET can create evictions, sending notifications which can cause to dirty++ with modules.
         we need to prevent it from propagating to AOF/replicas
      2. We need to set current_client in RM_Call. buggy scenario:
         - CONFIG SET maxmemory, eviction notifications, module hook calls RM_Call
         - assertion in lookupKey crashes, because current_client has CONFIG SET, which isn't CMD_WRITE
      3. minor: in eviction, call propagateDeletion after notification, like active-expire and all commands
         (we always send a notification before propagating the command)
      7ac21307
  16. 15 Dec, 2021 1 commit
    • guybe7's avatar
      Auto-generate the command table from JSON files (#9656) · 86781600
      guybe7 authored
      Delete the hardcoded command table and replace it with an auto-generated table, based
      on a JSON file that describes the commands (each command must have a JSON file).
      
      These JSON files are the SSOT of everything there is to know about Redis commands,
      and it is reflected fully in COMMAND INFO.
      
      These JSON files are used to generate commands.c (using a python script), which is then
      committed to the repo and compiled.
      
      The purpose is:
      * Clients and proxies will be able to get much more info from redis, instead of relying on hard coded logic.
      * drop the dependency between Redis-user and the commands.json in redis-doc.
      * delete help.h and have redis-cli learn everything it needs to know just by issuing COMMAND (will be
        done in a separate PR)
      * redis.io should stop using commands.json and learn everything from Redis (ultimately one of the release
        artifacts should be a large JSON, containing all the information about all of the commands, which will be
        generated from COMMAND's reply)
      * the byproduct of this is:
        * module commands will be able to provide that info and possibly be more of a first-class citizens
        * in theory, one may be able to generate a redis client library for a strictly typed language, by using this info.
      
      ### Interface changes
      
      #### COMMAND INFO's reply change (and arg-less COMMAND)
      
      Before this commit the reply at index 7 contained the key-specs list
      and reply at index 8 contained the sub-commands list (Both unreleased).
      Now, reply at index 7 is a map of:
      - summary - short command description
      - since - debut version
      - group - command group
      - complexity - complexity string
      - doc-flags - flags used for documentation (e.g. "deprecated")
      - deprecated-since - if deprecated, from which version?
      - replaced-by - if deprecated, which command replaced it?
      - history - a list of (version, what-changed) tuples
      - hints - a list of strings, meant to provide hints for clients/proxies. see https://github.com/redis/redis/issues/9876
      - arguments - an array of arguments. each element is a map, with the possibility of nesting (sub-arguments)
      - key-specs - an array of keys specs (already in unstable, just changed location)
      - subcommands - a list of sub-commands (already in unstable, just changed location)
      - reply-schema - will be added in the future (see https://github.com/redis/redis/issues/9845)
      
      more details on these can be found in https://github.com/redis/redis-doc/pull/1697
      
      only the first three fields are mandatory 
      
      #### API changes (unreleased API obviously)
      
      now they take RedisModuleCommand opaque pointer instead of looking up the command by name
      
      - RM_CreateSubcommand
      - RM_AddCommandKeySpec
      - RM_SetCommandKeySpecBeginSearchIndex
      - RM_SetCommandKeySpecBeginSearchKeyword
      - RM_SetCommandKeySpecFindKeysRange
      - RM_SetCommandKeySpecFindKeysKeynum
      
      Currently, we did not add module API to provide additional information about their commands because
      we couldn't agree on how the API should look like, see https://github.com/redis/redis/issues/9944
      
      .
      
      ### Somehow related changes
      1. Literals should be in uppercase while placeholder in lowercase. Now all the GEO* command
         will be documented with M|KM|FT|MI and can take both lowercase and uppercase
      
      ### Unrelated changes
      1. Bugfix: no_madaory_keys was absent in COMMAND's reply
      2. expose CMD_MODULE as "module" via COMMAND
      3. have a dedicated uint64 for ACL categories (instead of having them in the same uint64 as command flags)
      Co-authored-by: default avatarItamar Haber <itamar@garantiadata.com>
      86781600
  17. 28 Nov, 2021 1 commit
    • Viktor Söderqvist's avatar
      Sort out the mess around writable replicas and lookupKeyRead/Write (#9572) · acf3495e
      Viktor Söderqvist authored
      Writable replicas now no longer use the values of expired keys. Expired keys are
      deleted when lookupKeyWrite() is used, even on a writable replica. Previously,
      writable replicas could use the value of an expired key in write commands such
      as INCR, SUNIONSTORE, etc..
      
      This commit also sorts out the mess around the functions lookupKeyRead() and
      lookupKeyWrite() so they now indicate what we intend to do with the key and
      are not affected by the command calling them.
      
      Multi-key commands like SUNIONSTORE, ZUNIONSTORE, COPY and SORT with the
      store option now use lookupKeyRead() for the keys they're reading from (which will
      not allow reading from logically expired keys).
      
      This commit also fixes a bug where PFCOUNT could return a value of an
      expired key.
      
      Test modules commands have their readonly and write flags updated to correctly
      reflect their lookups for reading or writing. Modules are not required to
      correctly reflect this in their command flags, but this change is made for
      consistency since the tests serve as usage examples.
      
      Fixes #6842. Fixes #7475.
      acf3495e
  18. 23 Nov, 2021 1 commit
    • guybe7's avatar
      QUIT is a command, HOST: and POST are not (#9798) · b161cff5
      guybe7 authored
      Some people complain that QUIT is missing from help/command table.
      Not appearing in COMMAND command, command stats, ACL, etc.
      and instead, there's a hack in processCommand with a comment that looks outdated.
      Note that it is [documented](https://redis.io/commands/quit)
      
      At the same time, HOST: and POST are there in the command table although these are not real commands.
      They would appear in the COMMAND command, and even in commandstats.
      
      Other changes:
      1. Initialize the static logged_time static var in securityWarningCommand
      2. add `no-auth` flag to RESET so it can always be executed.
      b161cff5
  19. 04 Nov, 2021 1 commit
    • Eduardo Semprebon's avatar
      Replica keep serving data during repl-diskless-load=swapdb for better availability (#9323) · 91d0c758
      Eduardo Semprebon authored
      
      
      For diskless replication in swapdb mode, considering we already spend replica memory
      having a backup of current db to restore in case of failure, we can have the following benefits
      by instead swapping database only in case we succeeded in transferring db from master:
      
      - Avoid `LOADING` response during failed and successful synchronization for cases where the
        replica is already up and running with data.
      - Faster total time of diskless replication, because now we're moving from Transfer + Flush + Load
        time to Transfer + Load only. Flushing the tempDb is done asynchronously after swapping.
      - This could be implemented also for disk replication with similar benefits if consumers are willing
        to spend the extra memory usage.
      
      General notes:
      - The concept of `backupDb` becomes `tempDb` for clarity.
      - Async loading mode will only kick in if the replica is syncing from a master that has the same
        repl-id the one it had before. i.e. the data it's getting belongs to a different time of the same timeline. 
      - New property in INFO: `async_loading` to differentiate from the blocking loading
      - Slot to Key mapping is now a field of `redisDb` as it's more natural to access it from both server.db
        and the tempDb that is passed around.
      - Because this is affecting replicas only, we assume that if they are not readonly and write commands
        during replication, they are lost after SYNC same way as before, but we're still denying CONFIG SET
        here anyways to avoid complications.
      
      Considerations for review:
      - We have many cases where server.loading flag is used and even though I tried my best, there may
        be cases where async_loading should be checked as well and cases where it shouldn't (would require
        very good understanding of whole code)
      - Several places that had different behavior depending on the loading flag where actually meant to just
        handle commands coming from the AOF client differently than ones coming from real clients, changed
        to check CLIENT_ID_AOF instead.
      
      **Additional for Release Notes**
      - Bugfix - server.dirty was not incremented for any kind of diskless replication, as effect it wouldn't
        contribute on triggering next database SAVE
      - New flag for RM_GetContextFlags module API: REDISMODULE_CTX_FLAGS_ASYNC_LOADING
      - Deprecated RedisModuleEvent_ReplBackup. Starting from Redis 7.0, we don't fire this event.
        Instead, we have the new RedisModuleEvent_ReplAsyncLoad holding 3 sub-events: STARTED,
        ABORTED and COMPLETED.
      - New module flag REDISMODULE_OPTIONS_HANDLE_REPL_ASYNC_LOAD for RedisModule_SetModuleOptions
        to allow modules to declare they support the diskless replication with async loading (when absent, we fall
        back to disk-based loading).
      Co-authored-by: default avatarEduardo Semprebon <edus@saxobank.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      91d0c758
  20. 01 Nov, 2021 1 commit
    • Oran Agra's avatar
      fix valgrind issues with long double module test (#9709) · f1f3cceb
      Oran Agra authored
      The module test in reply.tcl was introduced by #8521 but didn't run until recently (see #9639)
      and then it started failing with valgrind.
      This is because valgrind uses 64 bit long double (unlike most other platforms that have at least 80 bits)
      But besides valgrind, the tests where also incompatible with ARM32, which also uses 64 bit long doubles.
      
      We now use appropriate value to avoid issues with either valgrind or ARM32
      
      In all the double tests, i use 3.141, which is safe since since addReplyDouble uses
      `%.17Lg` which is able to represent this value without adding any digits due to precision loss. 
      
      In the long double, since we use `%.17Lf` in ld2string, it preserves 17 significant
      digits, rather than 17 digit after the decimal point (like in `%.17Lg`).
      So to make these similar, i use value lower than 1 (no digits left of
      the period)
      
      Lastly, we have the same issue with TCL (no long doubles) so we read
      raw protocol in that test.
      
      Note that the only error before this fix (in both valgrind and ARM32 is this:
      ```
      *** [err]: RM_ReplyWithLongDouble: a float reply in tests/unit/moduleapi/reply.tcl
      Expected '3.141' to be equal to '3.14100000000000001' (context: type eval line 2 cmd {assert_equal 3.141 [r rw.longdouble 3.141]} proc ::test)
      ```
      so the changes to debug.c and scripting.tcl aren't really needed, but i consider them a cleanup
      (i.e. scripting.c validated a different constant than the one that's sent to it from debug.c).
      
      Another unrelated change is to add the RESP version to the repeated tests in reply.tcl
      f1f3cceb
  21. 31 Oct, 2021 1 commit
  22. 25 Oct, 2021 2 commits
  23. 21 Oct, 2021 1 commit
  24. 20 Oct, 2021 2 commits
    • Yossi Gottlieb's avatar
      8bf4c2e3
    • guybe7's avatar
      Treat subcommands as commands (#9504) · 43e736f7
      guybe7 authored
      ## Intro
      
      The purpose is to allow having different flags/ACL categories for
      subcommands (Example: CONFIG GET is ok-loading but CONFIG SET isn't)
      
      We create a small command table for every command that has subcommands
      and each subcommand has its own flags, etc. (same as a "regular" command)
      
      This commit also unites the Redis and the Sentinel command tables
      
      ## Affected commands
      
      CONFIG
      Used to have "admin ok-loading ok-stale no-script"
      Changes:
      1. Dropped "ok-loading" in all except GET (this doesn't change behavior since
      there were checks in the code doing that)
      
      XINFO
      Used to have "read-only random"
      Changes:
      1. Dropped "random" in all except CONSUMERS
      
      XGROUP
      Used to have "write use-memory"
      Changes:
      1. Dropped "use-memory" in all except CREATE and CREATECONSUMER
      
      COMMAND
      No changes.
      
      MEMORY
      Used to have "random read-only"
      Changes:
      1. Dropped "random" in PURGE and USAGE
      
      ACL
      Used to have "admin no-script ok-loading ok-stale"
      Changes:
      1. Dropped "admin" in WHOAMI, GENPASS, and CAT
      
      LATENCY
      No changes.
      
      MODULE
      No changes.
      
      SLOWLOG
      Used to have "admin random ok-loading ok-stale"
      Changes:
      1. Dropped "random" in RESET
      
      OBJECT
      Used to have "read-only random"
      Changes:
      1. Dropped "random" in ENCODING and REFCOUNT
      
      SCRIPT
      Used to have "may-replicate no-script"
      Changes:
      1. Dropped "may-replicate" in all except FLUSH and LOAD
      
      CLIENT
      Used to have "admin no-script random ok-loading ok-stale"
      Changes:
      1. Dropped "random" in all except INFO and LIST
      2. Dropped "admin" in ID, TRACKING, CACHING, GETREDIR, INFO, SETNAME, GETNAME, and REPLY
      
      STRALGO
      No changes.
      
      PUBSUB
      No changes.
      
      CLUSTER
      Changes:
      1. Dropped "admin in countkeysinslots, getkeysinslot, info, nodes, keyslot, myid, and slots
      
      SENTINEL
      No changes.
      
      (note that DEBUG also fits, but we decided not to convert it since it's for
      debugging and anyway undocumented)
      
      ## New sub-command
      This commit adds another element to the per-command output of COMMAND,
      describing the list of subcommands, if any (in the same structure as "regular" commands)
      Also, it adds a new subcommand:
      ```
      COMMAND LIST [FILTERBY (MODULE <module-name>|ACLCAT <cat>|PATTERN <pattern>)]
      ```
      which returns a set of all commands (unless filters), but excluding subcommands.
      
      ## Module API
      A new module API, RM_CreateSubcommand, was added, in order to allow
      module writer to define subcommands
      
      ## ACL changes:
      1. Now, that each subcommand is actually a command, each has its own ACL id.
      2. The old mechanism of allowed_subcommands is redundant
      (blocking/allowing a subcommand is the same as blocking/allowing a regular command),
      but we had to keep it, to support the widespread usage of allowed_subcommands
      to block commands with certain args, that aren't subcommands (e.g. "-select +select|0").
      3. I have renamed allowed_subcommands to allowed_firstargs to emphasize the difference.
      4. Because subcommands are commands in ACL too, you can now use "-" to block subcommands
      (e.g. "+client -client|kill"), which wasn't possible in the past.
      5. It is also possible to use the allowed_firstargs mechanism with subcommand.
      For example: `+config -config|set +config|set|loglevel` will block all CONFIG SET except
      for setting the log level.
      6. All of the ACL changes above required some amount of refactoring.
      
      ## Misc
      1. There are two approaches: Either each subcommand has its own function or all
         subcommands use the same function, determining what to do according to argv[0].
         For now, I took the former approaches only with CONFIG and COMMAND,
         while other commands use the latter approach (for smaller blamelog diff).
      2. Deleted memoryGetKeys: It is no longer needed because MEMORY USAGE now uses the "range" key spec.
      4. Bugfix: GETNAME was missing from CLIENT's help message.
      5. Sentinel and Redis now use the same table, with the same function pointer.
         Some commands have a different implementation in Sentinel, so we redirect
         them (these are ROLE, PUBLISH, and INFO).
      6. Command stats now show the stats per subcommand (e.g. instead of stats just
         for "config" you will have stats for "config|set", "config|get", etc.)
      7. It is now possible to use COMMAND directly on subcommands:
         COMMAND INFO CONFIG|GET (The pipeline syntax was inspired from ACL, and
         can be used in functions lookupCommandBySds and lookupCommandByCString)
      8. STRALGO is now a container command (has "help")
      
      ## Breaking changes:
      1. Command stats now show the stats per subcommand (see (5) above)
      43e736f7
  25. 19 Oct, 2021 1 commit
    • qetu3790's avatar
      Release clients blocked on module commands in cluster resharding and down state (#9483) · 4962c552
      qetu3790 authored
      
      
      Prevent clients from being blocked forever in cluster when they block with their own module command
      and the hash slot is migrated to another master at the same time.
      These will get a redirection message when unblocked.
      Also, release clients blocked on module commands when cluster is down (same as other blocked clients)
      
      This commit adds basic tests for the main (non-cluster) redis test infra that test the cluster.
      This was done because the cluster test infra can't handle some common test features,
      but most importantly we only build the test modules with the non-cluster test suite.
      
      note that rather than really supporting cluster operations by the test infra, it was added (as dup code)
      in two files, one for module tests and one for non-modules tests, maybe in the future we'll refactor that.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      4962c552
  26. 18 Oct, 2021 1 commit
  27. 17 Oct, 2021 1 commit
  28. 16 Oct, 2021 1 commit
  29. 30 Sep, 2021 1 commit
  30. 23 Sep, 2021 2 commits
    • Yossi Gottlieb's avatar
      Add RM_TrimStringAllocation(). (#9540) · bebc7f84
      Yossi Gottlieb authored
      This commit makes it possible to explicitly trim the allocation of a
      RedisModuleString.
      
      Currently, Redis automatically trims strings that have been retained by
      a module command when it returns. However, this is not thread safe and
      may result with corruption in threaded modules.
      
      Supporting explicit trimming offers a backwards compatible workaround to
      this problem.
      bebc7f84
    • YaacovHazan's avatar
      Adding ACL support for modules (#9309) · a56d4533
      YaacovHazan authored
      This commit introduced a new flag to the RM_Call:
      'C' - Check if the command can be executed according to the ACLs associated with it.
      
      Also, three new API's added to check if a command, key, or channel can be executed or accessed
      by a user, according to the ACLs associated with it.
      - RM_ACLCheckCommandPerm
      - RM_ACLCheckKeyPerm
      - RM_ACLCheckChannelPerm
      
      The user for these API's is a RedisModuleUser object, that for a Module user returned by the RM_CreateModuleUser API, or for a general ACL user can be retrieved by these two new API's:
      - RM_GetCurrentUserName - Retrieve the user name of the client connection behind the current context.
      - RM_GetModuleUserFromUserName - Get a RedisModuleUser from a user name
      
      As a result of getting a RedisModuleUser from name, it can now also access the general ACL users (not just ones created by the module).
      This mean the already existing API RM_SetModuleUserACL(), can be used to change the ACL rules for such users.
      a56d4533
  31. 15 Sep, 2021 1 commit
    • guybe7's avatar
      A better approach for COMMAND INFO for movablekeys commands (#8324) · 03fcc211
      guybe7 authored
      Fix #7297
      
      The problem:
      
      Today, there is no way for a client library or app to know the key name indexes for commands such as
      ZUNIONSTORE/EVAL and others with "numkeys", since COMMAND INFO returns no useful info for them.
      
      For cluster-aware redis clients, this requires to 'patch' the client library code specifically for each of these commands or to
      resolve each execution of these commands with COMMAND GETKEYS.
      
      The solution:
      
      Introducing key specs other than the legacy "range" (first,last,step)
      
      The 8th element of the command info array, if exists, holds an array of key specs. The array may be empty, which indicates
      the command doesn't take any key arguments or may contain one or more key-specs, each one may leads to the discovery
      of 0 or more key arguments.
      
      A client library that doesn't support this key-spec feature will keep using the first,last,step and movablekeys flag which will
      obviously remain unchanged.
      
      A client that supports this key-specs feature needs only to look at the key-specs array. If it finds an unrecognized spec, it
      must resort to using COMMAND GETKEYS if it wishes to get all key name arguments, but if all it needs is one key in order
      to know which cluster node to use, then maybe another spec (if the command has several) can supply that, and there's no
      need to use GETKEYS.
      
      Each spec is an array of arguments, first one is the spec name, the second is an array of flags, and the third is an array
      containing details about the spec (specific meaning for each spec type)
      The initial flags we support are "read" and "write" indicating if the keys that this key-spec finds are used for read or for write.
      clients should ignore any unfamiliar flags.
      
      In order to easily find the positions of keys in a given array of args we introduce keys specs. There are two logical steps of
      key specs:
      1. `start_search`: Given an array of args, indicate where we should start searching for keys
      2. `find_keys`: Given the output of start_search and an array of args, indicate all possible indices of keys.
      
      ### start_search step specs
      - `index`: specify an argument index explicitly
        - `index`: 0 based index (1 means the first command argument)
      - `keyword`: specify a string to match in `argv`. We should start searching for keys just after the keyword appears.
        - `keyword`: the string to search for
        - `start_search`: an index from which to start the keyword search (can be negative, which means to search from the end)
      
      Examples:
      - `SET` has start_search of type `index` with value `1`
      - `XREAD` has start_search of type `keyword` with value `[“STREAMS”,1]`
      - `MIGRATE` has start_search of type `keyword` with value `[“KEYS”,-2]`
      
      ### find_keys step specs
      - `range`: specify `[count, step, limit]`.
        - `lastkey`: index of the last key. relative to the index returned from begin_search. -1 indicating till the last argument, -2 one before the last
        - `step`: how many args should we skip after finding a key, in order to find the next one
        - `limit`: if count is -1, we use limit to stop the search by a factor. 0 and 1 mean no limit. 2 means ½ of the remaining args, 3 means ⅓, and so on.
      - “keynum”: specify `[keynum_index, first_key_index, step]`.
        - `keynum_index`: is relative to the return of the `start_search` spec.
        - `first_key_index`: is relative to `keynum_index`.
        - `step`: how many args should we skip after finding a key, in order to find the next one
      
      Examples:
      - `SET` has `range` of `[0,1,0]`
      - `MSET` has `range` of `[-1,2,0]`
      - `XREAD` has `range` of `[-1,1,2]`
      - `ZUNION` has `start_search` of type `index` with value `1` and `find_keys` of type `keynum` with value `[0,1,1]`
      - `AI.DAGRUN` has `start_search` of type `keyword` with value `[“LOAD“,1]` and `find_keys` of type `keynum` with value
        `[0,1,1]` (see https://oss.redislabs.com/redisai/master/commands/#aidagrun)
      
      Note: this solution is not perfect as the module writers can come up with anything, but at least we will be able to find the key
      args of the vast majority of commands.
      If one of the above specs can’t describe the key positions, the module writer can always fall back to the `getkeys-api` option.
      
      Some keys cannot be found easily (`KEYS` in `MIGRATE`: Imagine the argument for `AUTH` is the string “KEYS” - we will
      start searching in the wrong index). 
      The guarantee is that the specs may be incomplete (`incomplete` will be specified in the spec to denote that) but we never
      report false information (assuming the command syntax is correct).
      For `MIGRATE` we start searching from the end - `startfrom=-1` - and if one of the keys is actually called "keys" we will
      report only a subset of all keys - hence the `incomplete` flag.
      Some `incomplete` specs can be completely empty (i.e. UNKNOWN begin_search) which should tell the client that
      COMMAND GETKEYS (or any other way to get the keys) must be used (Example: For `SORT` there is no way to describe
      the STORE keyword spec, as the word "store" can appear anywhere in the command).
      
      We will expose these key specs in the `COMMAND` command so that clients can learn, on startup, where the keys are for
      all commands instead of holding hardcoded tables or use `COMMAND GETKEYS` in runtime.
      
      Comments:
      1. Redis doesn't internally use the new specs, they are only used for COMMAND output.
      2. In order to support the current COMMAND INFO format (reply array indices 4, 5, 6) we created a synthetic range, called
         legacy_range, that, if possible, is built according to the new specs.
      3. Redis currently uses only getkeys_proc or the legacy_range to get the keys indices (in COMMAND GETKEYS for
         example).
      
      "incomplete" specs:
      the command we have issues with are MIGRATE, STRALGO, and SORT
      for MIGRATE, because the token KEYS, if exists, must be the last token, we can search in reverse. it one of the keys is
      actually the string "keys" will return just a subset of the keys (hence, it's "incomplete")
      for SORT and STRALGO we can use this heuristic (the keys can be anywhere in the command) and therefore we added a
      key spec that is both "incomplete" and of "unknown type"
      
      if a client encounters an "incomplete" spec it means that it must find a different way (either COMMAND GETKEYS or have
      its own parser) to retrieve the keys.
      please note that all commands, apart from the three mentioned above, have "complete" key specs
      03fcc211
  32. 14 Sep, 2021 2 commits
    • Viktor Söderqvist's avatar
      Modules: Add remaining list API functions (#8439) · ea36d4de
      Viktor Söderqvist authored
      List functions operating on elements by index:
      
      * RM_ListGet
      * RM_ListSet
      * RM_ListInsert
      * RM_ListDelete
      
      Iteration is done using a simple for loop over indices.
      The index based functions use an internal iterator as an optimization.
      This is explained in the docs:
      
      ```
       * Many of the list functions access elements by index. Since a list is in
       * essence a doubly-linked list, accessing elements by index is generally an
       * O(N) operation. However, if elements are accessed sequentially or with
       * indices close together, the functions are optimized to seek the index from
       * the previous index, rather than seeking from the ends of the list.
       *
       * This enables iteration to be done efficiently using a simple for loop:
       *
       *     long n = RM_ValueLength(key);
       *     for (long i = 0; i < n; i++) {
       *         RedisModuleString *elem = RedisModule_ListGet(key, i);
       *         // Do stuff...
       *     }
      ```
      ea36d4de
    • sundb's avatar
      Fix memory leak due to missing freeCallback in blockonbackground moduleapi test (#9499) · 1376d833
      sundb authored
      Before #9497, before redis-server was shut down, we did not manually shut down all the clients,
      which would have prevented valgrind from detecting a memory leak in the client's argc.
      1376d833