1. 18 Aug, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Fix replication inconsistency on modules that uses key space notifications (#10969) · 508a1388
      Meir Shpilraien (Spielrein) authored
      Fix replication inconsistency on modules that uses key space notifications.
      
      ### The Problem
      
      In general, key space notifications are invoked after the command logic was
      executed (this is not always the case, we will discuss later about specific
      command that do not follow this rules). For example, the `set x 1` will trigger
      a `set` notification that will be invoked after the `set` logic was performed, so
      if the notification logic will try to fetch `x`, it will see the new data that was written.
      Consider the scenario on which the notification logic performs some write
      commands. for example, the notification logic increase some counter,
      `incr x{counter}`, indicating how many times `x` was changed.
      The logical order by which the logic was executed is has follow:
      
      ```
      set x 1
      incr x{counter}
      ```
      
      The issue is that the `set x 1` command is added to the replication buffer
      at the end of the command invocation (specifically after the key space
      notification logic was invoked and performed the `incr` command).
      The replication/aof sees the commands in the wrong order:
      
      ```
      incr x{counter}
      set x 1
      ```
      
      In this specific example the order is less important.
      But if, for example, the notification would have deleted `x` then we would
      end up with primary-replica inconsistency.
      
      ### The Solution
      
      Put the command that cause the notification in its rightful place. In the
      above example, the `set x 1` command logic was executed before the
      notification logic, so it should be added to the replication buffer before
      the commands that is invoked by the notification logic. To achieve this,
      without a major code refactoring, we save a placeholder in the replication
      buffer, when finishing invoking the command logic we check if the command
      need to be replicated, and if it does, we use the placeholder to add it to the
      replication buffer instead of appending it to the end.
      
      To be efficient and not allocating memory on each command to save the
      placeholder, the replication buffer array was modified to reuse memory
      (instead of allocating it each time we want to replicate commands).
      Also, to avoid saving a placeholder when not needed, we do it only for
      WRITE or MAY_REPLICATE commands.
      
      #### Additional Fixes
      
      * Expire and Eviction notifications:
        * Expire/Eviction logical order was to first perform the Expire/Eviction
          and then the notification logic. The replication buffer got this in the
          other way around (first notification effect and then the `del` command).
          The PR fixes this issue.
        * The notification effect and the `del` command was not wrap with
          `multi-exec` (if needed). The PR also fix this issue.
      * SPOP command:
        * On spop, the `spop` notification was fired before the command logic
          was executed. The change in this PR would have cause the replication
          order to be change (first `spop` command and then notification `logic`)
          although the logical order is first the notification logic and then the
          `spop` logic. The right fix would have been to move the notification to
          be fired after the command was executed (like all the other commands),
          but this can be considered a breaking change. To overcome this, the PR
          keeps the current behavior and changes the `spop` code to keep the right
          logical order when pushing commands to the replication buffer. Another PR
          will follow to fix the SPOP properly and match it to the other command (we
          split it to 2 separate PR's so it will be easy to cherry-pick this PR to 7.0 if
          we chose to).
      
      #### Unhanded Known Limitations
      
      * key miss event:
        * On key miss event, if a module performed some write command on the
          event (using `RM_Call`), the `dirty` counter would increase and the read
          command that cause the key miss event would be replicated to the replication
          and aof. This problem can also happened on a write command that open
          some keys but eventually decides not to perform any action. We decided
          not to handle this problem on this PR because the solution is complex
          and will cause additional risks in case we will want to cherry-pick this PR.
          We should decide if we want to handle it in future PR's. For now, modules
          writers is advice not to perform any write commands on key miss event.
      
      #### Testing
      
      * We already have tests to cover cases where a notification is invoking write
        commands that are also added to the replication buffer, the tests was modified
        to verify that the replica gets the command in the correct logical order.
      * Test was added to verify that `spop` behavior was kept unchanged.
      * Test was added to verify key miss event behave as expected.
      * Test was added to verify the changes do not break lazy expiration.
      
      #### Additional Changes
      
      * `propagateNow` function can accept a special dbid, -1, indicating not
        to replicate `select`. We use this to replicate `multi/exec` on `propagatePendingCommands`
        function. The side effect of this change is that now the `select` command
        will appear inside the `multi/exec` block on the replication stream (instead of
        outside of the `multi/exec` block). Tests was modified to match this new behavior.
      508a1388
  2. 02 Aug, 2022 1 commit
    • Binbin's avatar
      Solve usleep compilation warning in keyspace_events.c (#11073) · 9f0f533b
      Binbin authored
      There is a -Wimplicit-function-declaration warning in here:
      ```
      keyspace_events.c: In function ‘KeySpace_NotificationGeneric’:
      keyspace_events.c:67:9: warning: implicit declaration of function ‘usleep’; did you mean ‘sleep’? [-Wimplicit-function-declaration]
         67 |         usleep(1);
            |         ^~~~~~
            |         sleep
      ```
      9f0f533b
  3. 27 Jul, 2022 1 commit
    • guybe7's avatar
      Adds RM_Microseconds and RM_CachedMicroseconds (#11016) · 45c99d70
      guybe7 authored
      RM_Microseconds
      Return the wall-clock Unix time, in microseconds
      
      RM_CachedMicroseconds
      Returns a cached copy of the Unix time, in microseconds.
      It is updated in the server cron job and before executing a command.
      It is useful for complex call stacks, such as a command causing a
      key space notification, causing a module to execute a RedisModule_Call,
      causing another notification, etc.
      It makes sense that all these callbacks would use the same clock.
      45c99d70
  4. 18 Jul, 2022 1 commit
    • ranshid's avatar
      Avoid using unsafe C functions (#10932) · eacca729
      ranshid authored
      replace use of:
      sprintf --> snprintf
      strcpy/strncpy  --> redis_strlcpy
      strcat/strncat  --> redis_strlcat
      
      **why are we making this change?**
      Much of the code uses some unsafe variants or deprecated buffer handling
      functions.
      While most cases are probably not presenting any issue on the known path
      programming errors and unterminated strings might lead to potential
      buffer overflows which are not covered by tests.
      
      **As part of this PR we change**
      1. added implementation for redis_strlcpy and redis_strlcat based on the strl implementation: https://linux.die.net/man/3/strl
      2. change all occurrences of use of sprintf with use of snprintf
      3. change occurrences of use of  strcpy/strncpy with redis_strlcpy
      4. change occurrences of use of strcat/strncat with redis_strlcat
      5. change the behavior of ll2string/ull2string/ld2string so that it will always place null
        termination ('\0') on the output buffer in the first index. this was done in order to make
        the use of these functions more safe in cases were the user will not check the output
        returned by them (for example in rdbRemoveTempFile)
      6. we added a compiler directive to issue a deprecation error in case a use of
        sprintf/strcpy/strcat is found during compilation which will result in error during compile time.
        However keep in mind that since the deprecation attribute is not supported on all compilers,
        this is expected to fail during push workflows.
      
      
      **NOTE:** while this is only an initial milestone. We might also consider
      using the *_s implementation provided by the C11 Extensions (however not
      yet widly supported). I would also suggest to start
      looking at static code analyzers to track unsafe use cases.
      For example LLVM clang checker supports security.insecureAPI.DeprecatedOrUnsafeBufferHandling
      which can help locate unsafe function usage.
      https://clang.llvm.org/docs/analyzer/checkers.html#security-insecureapi-deprecatedorunsafebufferhandling-c
      The main reason not to onboard it at this stage is that the alternative
      excepted by clang is to use the C11 extensions which are not always
      supported by stdlib.
      eacca729
  5. 27 Jun, 2022 1 commit
    • Viktor Söderqvist's avatar
      Add missing REDISMODULE_CLIENTINFO_INITIALIZER (#10885) · 6af02100
      Viktor Söderqvist authored
      The module API docs mentions this macro, but it was not defined (so no one could have used it).
      
      Instead of adding it as is, we decided to add a _V1 macro, so that if / when we some day extend this struct,
      modules that use this API and don't need the extra fields, will still use the old version
      and still be compatible with older redis version (despite being compiled with newer redismodule.h)
      6af02100
  6. 26 Jun, 2022 2 commits
  7. 21 Jun, 2022 1 commit
    • Meir Shpilraien (Spielrein)'s avatar
      Fix crash on RM_Call with script mode. (#10886) · 61baabd8
      Meir Shpilraien (Spielrein) authored
      The PR fixes 2 issues:
      
      ### RM_Call crash on script mode
      
      `RM_Call` can potentially be called from a background thread where `server.current_client`
      are not set. In such case we get a crash on `NULL` dereference.
      The fix is to check first if `server.current_client` is `NULL`, if it does we should
      verify disc errors and readonly replica as we do to any normal clients (no masters nor AOF).
      
      ### RM_Call block OOM commands when not needed
      
      Again `RM_Call` can be executed on a background thread using a `ThreadSafeCtx`.
      In such case `server.pre_command_oom_state` can be irrelevant and should not be
      considered when check OOM state. This cause OOM commands to be blocked when
      not necessarily needed.
      
      In such case, check the actual used memory (and not the cached value). Notice that in
      order to know if the cached value can be used, we check that the ctx that was used on
      the `RM_Call` is a ThreadSafeCtx. Module writer can potentially abuse the API and use
      ThreadSafeCtx on the main thread. We consider this as a API miss used.
      61baabd8
  8. 12 Jun, 2022 1 commit
    • Binbin's avatar
      Fixed SET and BITFIELD commands being wrongly marked movablekeys (#10837) · 92fb4f4f
      Binbin authored
      
      
      The SET and BITFIELD command were added `get_keys_function` in #10148, causing
      them to be wrongly marked movablekeys in `populateCommandMovableKeys`.
      
      This was an unintended side effect introduced in #10148 (7.0 RC1)
      which could cause some clients an extra round trip for these commands in cluster mode.
      
      Since we define movablekeys as a way to determine if the legacy range [first, last, step]
      doesn't find all keys, then we need a completely different approach.
      
      The right approach should be to check if the legacy range covers all key-specs,
      and if none of the key-specs have the INCOMPLETE flag. 
      This way, we don't need to look at getkeys_proc of VARIABLE_FLAG at all.
      Probably with the exception of modules, who may still not be using key-specs.
      
      In this PR, we removed `populateCommandMovableKeys` and put its logic in
      `populateCommandLegacyRangeSpec`.
      In order to properly serve both old and new modules, we must probably keep relying
      CMD_MODULE_GETKEYS, but do that only for modules that don't declare key-specs. 
      For ones that do, we need to take the same approach we take with native redis commands.
      
      This approach was proposed by Oran. Fixes #10833
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      92fb4f4f
  9. 01 Jun, 2022 1 commit
    • Oran Agra's avatar
      Fix broken protocol in MISCONF error, RM_Yield bugs, RM_Call(EVAL) OOM check... · b2061de2
      Oran Agra authored
      Fix broken protocol in MISCONF error, RM_Yield bugs, RM_Call(EVAL) OOM check bug, and new RM_Call checks. (#10786)
      
      * Fix broken protocol when redis can't persist to RDB (general commands, not
        modules), excessive newline. regression of #10372 (7.0 RC3)
      * Fix broken protocol when Redis can't persist to AOF (modules and
        scripts), missing newline.
      * Fix bug in OOM check of EVAL scripts called from RM_Call.
        set the cached OOM state for scripts before executing module commands too,
        so that it can serve scripts that are executed by modules.
        i.e. in the past EVAL executed by RM_Call could have either falsely
        fail or falsely succeeded because of a wrong cached OOM state flag.
      * Fix bugs with RM_Yield:
        1. SHUTDOWN should only accept the NOSAVE mode
        2. Avoid eviction during yield command processing.
        3. Avoid processing master client commands while yielding from another client
      * Add new two more checks to RM_Call script mode.
        1. READONLY You can't write against a read only replica
        2. MASTERDOWN Link with MASTER is down and `replica-serve-stale-data` is set to `no`
      * Add new RM_Call flag to let redis automatically refuse `deny-oom` commands
        while over the memory limit. 
      * Add tests to cover various errors from Scripts, Modules, Modules
        calling scripts, and Modules calling commands in script mode.
      
      Add tests:
      * Looks like the MISCONF error was completely uncovered by the tests,
        add tests for it, including from scripts, and modules
      * Add tests for NOREPLICAS from scripts
      * Add tests for the various errors in module RM_Call, including RM_Call that
        calls EVAL, and RM_call in "eval mode". that includes:
        NOREPLICAS, READONLY, MASTERDOWN, MISCONF
      b2061de2
  10. 12 May, 2022 1 commit
    • Binbin's avatar
      Fix race in module fork kill test (#10717) · 586a16ad
      Binbin authored
      The purpose of the test is to kill the child while it is running.
      From the last two lines we can see the child exits before being killed.
      ```
      - Module fork started pid: 56998
      * <fork> fork child started
      - Killing running module fork child: 56998
      * <fork> fork child exiting
      signal-handler (1652267501) Received SIGUSR1 in child, exiting now.
      ```
      
      In this commit, we pass an argument to `fork.create` indicating how
      long it should sleep. For the fork kill test, we use a longer time to
      avoid the child exiting before being killed.
      
      Other changes:
      use wait_for_condition instead of hardcoded `after 250`.
      Unify the test for failing fork with the one for killing it (save time) 
      586a16ad
  11. 09 May, 2022 1 commit
  12. 26 Apr, 2022 2 commits
    • Oran Agra's avatar
      Add module API flag for using enum configs as bit flags (#10643) · 81926254
      Oran Agra authored
      Enables registration of an enum config that'll let the user pass multiple keywords that
      will be combined with `|` as flags into the integer config value.
      
      ```
          const char *enum_vals[] = {"none", "one", "two", "three"};
          const int int_vals[] = {0, 1, 2, 4};
      
          if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 4, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
              return REDISMODULE_ERR;
          }
      ```
      doing:
      `config set moduleconfigs.flags "two three"` will result in 6 being passed to`setFlagsConfigCommand`.
      81926254
    • Eduardo Semprebon's avatar
      Allow configuring signaled shutdown flags (#10594) · 3a1d1425
      Eduardo Semprebon authored
      
      
      The SHUTDOWN command has various flags to change it's default behavior,
      but in some cases establishing a connection to redis is complicated and it's easier
      for the management software to use signals. however, so far the signals could only
      trigger the default shutdown behavior.
      Here we introduce the option to control shutdown arguments for SIGTERM and SIGINT.
      
      New config options:
      `shutdown-on-sigint [nosave | save] [now] [force]` 
      `shutdown-on-sigterm [nosave | save] [now] [force]`
      
      Implementation:
      Support MULTI_ARG_CONFIG on createEnumConfig to support multiple enums to be applied as bit flags.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      3a1d1425
  13. 25 Apr, 2022 2 commits
    • guybe7's avatar
      Fix regression not aborting transaction on error, and re-edit some error responses (#10612) · df787764
      guybe7 authored
      1. Disk error and slave count checks didn't flag the transactions or counted correctly in command stats (regression from #10372  , 7.0 RC3)
      2. RM_Call will reply the same way Redis does, in case of non-exisitng command or arity error
      3. RM_WrongArtiy will consider the full command name
      4. Use lowercase 'u' in "unknonw subcommand" (to align with "unknown command")
      
      Followup work of #10127
      df787764
    • guybe7's avatar
      Test: RM_Call from within "expired" notification (#10613) · 21e39ec4
      guybe7 authored
      This case is interesting because it originates from cron,
      rather than from another command.
      
      The idea came from looking at #9890 and #10573, and I was wondering if RM_Call
      would work properly when `server.current_client == NULL`
      21e39ec4
  14. 17 Apr, 2022 2 commits
    • guybe7's avatar
      Add RM_PublishMessageShard (#10543) · f49ff156
      guybe7 authored
      since PUBLISH and SPUBLISH use different dictionaries for channels and clients,
      and we already have an API for PUBLISH, it only makes sense to have one for SPUBLISH
      
      Add test coverage and unifying some test infrastructure.
      f49ff156
    • guybe7's avatar
      Add RM_MallocSizeString, RM_MallocSizeDict (#10542) · fe1c096b
      guybe7 authored
      Add APIs to allow modules to compute the memory consumption of opaque objects owned by redis.
      Without these, the mem_usage callbacks of module data types are useless in many cases.
      
      Other changes:
      Fix streamRadixTreeMemoryUsage to include the size of the rax structure itself
      fe1c096b
  15. 12 Apr, 2022 1 commit
  16. 05 Apr, 2022 2 commits
  17. 31 Mar, 2022 1 commit
    • sundb's avatar
      Fix failing moduleconfigs tests and memory leak (#10501) · b8eb2a73
      sundb authored
      Fix global `strval` not reset to NULL after being freed, causing a crash on alpine
      (most likely because the dynamic library loader doesn't init globals on reload)
      By the way, fix the memory leak of using `RedisModule_Free` to free `RedisModuleString`,
      and add a corresponding test.
      b8eb2a73
  18. 30 Mar, 2022 1 commit
    • Nick Chun's avatar
      Module Configurations (#10285) · bda9d74d
      Nick Chun authored
      
      
      This feature adds the ability to add four different types (Bool, Numeric,
      String, Enum) of configurations to a module to be accessed via the redis
      config file, and the CONFIG command.
      
      **Configuration Names**:
      
      We impose a restriction that a module configuration always starts with the
      module name and contains a '.' followed by the config name. If a module passes
      "config1" as the name to a register function, it will be registered as MODULENAME.config1.
      
      **Configuration Persistence**:
      
      Module Configurations exist only as long as a module is loaded. If a module is
      unloaded, the configurations are removed.
      There is now also a minimal core API for removal of standardConfig objects
      from configs by name.
      
      **Get and Set Callbacks**:
      
      Storage of config values is owned by the module that registers them, and provides
      callbacks for Redis to access and manipulate the values.
      This is exposed through a GET and SET callback.
      
      The get callback returns a typed value of the config to redis. The callback takes
      the name of the configuration, and also a privdata pointer. Note that these only
      take the CONFIGNAME portion of the config, not the entire MODULENAME.CONFIGNAME.
      
      ```
       typedef RedisModuleString * (*RedisModuleConfigGetStringFunc)(const char *name, void *privdata);
       typedef long long (*RedisModuleConfigGetNumericFunc)(const char *name, void *privdata);
       typedef int (*RedisModuleConfigGetBoolFunc)(const char *name, void *privdata);
       typedef int (*RedisModuleConfigGetEnumFunc)(const char *name, void *privdata);
      ```
      
      Configs must also must specify a set callback, i.e. what to do on a CONFIG SET XYZ 123
      or when loading configurations from cli/.conf file matching these typedefs. *name* is
      again just the CONFIGNAME portion, *val* is the parsed value from the core,
      *privdata* is the registration time privdata pointer, and *err* is for providing errors to a client.
      
      ```
      typedef int (*RedisModuleConfigSetStringFunc)(const char *name, RedisModuleString *val, void *privdata, RedisModuleString **err);
      typedef int (*RedisModuleConfigSetNumericFunc)(const char *name, long long val, void *privdata, RedisModuleString **err);
      typedef int (*RedisModuleConfigSetBoolFunc)(const char *name, int val, void *privdata, RedisModuleString **err);
      typedef int (*RedisModuleConfigSetEnumFunc)(const char *name, int val, void *privdata, RedisModuleString **err);
      ```
      
      Modules can also specify an optional apply callback that will be called after
      value(s) have been set via CONFIG SET:
      
      ```
      typedef int (*RedisModuleConfigApplyFunc)(RedisModuleCtx *ctx, void *privdata, RedisModuleString **err);
      ```
      
      **Flags:**
      We expose 7 new flags to the module, which are used as part of the config registration.
      
      ```
      #define REDISMODULE_CONFIG_MODIFIABLE 0 /* This is the default for a module config. */
      #define REDISMODULE_CONFIG_IMMUTABLE (1ULL<<0) /* Can this value only be set at startup? */
      #define REDISMODULE_CONFIG_SENSITIVE (1ULL<<1) /* Does this value contain sensitive information */
      #define REDISMODULE_CONFIG_HIDDEN (1ULL<<4) /* This config is hidden in `config get <pattern>` (used for tests/debugging) */
      #define REDISMODULE_CONFIG_PROTECTED (1ULL<<5) /* Becomes immutable if enable-protected-configs is enabled. */
      #define REDISMODULE_CONFIG_DENY_LOADING (1ULL<<6) /* This config is forbidden during loading. */
      /* Numeric Specific Configs */
      #define REDISMODULE_CONFIG_MEMORY (1ULL<<7) /* Indicates if this value can be set as a memory value */
      ```
      
      **Module Registration APIs**:
      
      ```
      int (*RedisModule_RegisterBoolConfig)(RedisModuleCtx *ctx, char *name, int default_val, unsigned int flags, RedisModuleConfigGetBoolFunc getfn, RedisModuleConfigSetBoolFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
      int (*RedisModule_RegisterNumericConfig)(RedisModuleCtx *ctx, const char *name, long long default_val, unsigned int flags, long long min, long long max, RedisModuleConfigGetNumericFunc getfn, RedisModuleConfigSetNumericFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
      int (*RedisModule_RegisterStringConfig)(RedisModuleCtx *ctx, const char *name, const char *default_val, unsigned int flags, RedisModuleConfigGetStringFunc getfn, RedisModuleConfigSetStringFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
      int (*RedisModule_RegisterEnumConfig)(RedisModuleCtx *ctx, const char *name, int default_val, unsigned int flags, const char **enum_values, const int *int_values, int num_enum_vals, RedisModuleConfigGetEnumFunc getfn, RedisModuleConfigSetEnumFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
      int (*RedisModule_LoadConfigs)(RedisModuleCtx *ctx);
      ```
      
      The module name will be auto appended along with a "." to the front of the name of the config.
      
      **What RM_Register[...]Config does**:
      
      A RedisModule struct now keeps a list of ModuleConfig objects which look like:
      ```
      typedef struct ModuleConfig {
          sds name; /* Name of config without the module name appended to the front */
          void *privdata; /* Optional data passed into the module config callbacks */
          union get_fn { /* The get callback specificed by the module */
              RedisModuleConfigGetStringFunc get_string;
              RedisModuleConfigGetNumericFunc get_numeric;
              RedisModuleConfigGetBoolFunc get_bool;
              RedisModuleConfigGetEnumFunc get_enum;
          } get_fn;
          union set_fn { /* The set callback specified by the module */
              RedisModuleConfigSetStringFunc set_string;
              RedisModuleConfigSetNumericFunc set_numeric;
              RedisModuleConfigSetBoolFunc set_bool;
              RedisModuleConfigSetEnumFunc set_enum;
          } set_fn;
          RedisModuleConfigApplyFunc apply_fn;
          RedisModule *module;
      } ModuleConfig;
      ```
      It also registers a standardConfig in the configs array, with a pointer to the
      ModuleConfig object associated with it.
      
      **What happens on a CONFIG GET/SET MODULENAME.MODULECONFIG:**
      
      For CONFIG SET, we do the same parsing as is done in config.c and pass that
      as the argument to the module set callback. For CONFIG GET, we call the
      module get callback and return that value to config.c to return to a client.
      
      **CONFIG REWRITE**:
      
      Starting up a server with module configurations in a .conf file but no module load
      directive will fail. The flip side is also true, specifying a module load and a bunch
      of module configurations will load those configurations in using the module defined
      set callbacks on a RM_LoadConfigs call. Configs being rewritten works the same
      way as it does for standard configs, as the module has the ability to specify a
      default value. If a module is unloaded with configurations specified in the .conf file
      those configurations will be commented out from the .conf file on the next config rewrite.
      
      **RM_LoadConfigs:**
      
      `RedisModule_LoadConfigs(RedisModuleCtx *ctx);`
      
      This last API is used to make configs available within the onLoad() after they have
      been registered. The expected usage is that a module will register all of its configs,
      then call LoadConfigs to trigger all of the set callbacks, and then can error out if any
      of them were malformed. LoadConfigs will attempt to set all configs registered to
      either a .conf file argument/loadex argument or their default value if an argument is
      not specified. **LoadConfigs is a required function if configs are registered.
      ** Also note that LoadConfigs **does not** call the apply callbacks, but a module
      can do that directly after the LoadConfigs call.
      
      **New Command: MODULE LOADEX [CONFIG NAME VALUE] [ARGS ...]:**
      
      This command provides the ability to provide startup context information to a module.
      LOADEX stands for "load extended" similar to GETEX. Note that provided config
      names need the full MODULENAME.MODULECONFIG name. Any additional
      arguments a module might want are intended to be specified after ARGS.
      Everything after ARGS is passed to onLoad as RedisModuleString **argv.
      Co-authored-by: default avatarMadelyn Olson <madelyneolson@gmail.com>
      Co-authored-by: default avatarMadelyn Olson <matolson@amazon.com>
      Co-authored-by: default avatarsundb <sundbcn@gmail.com>
      Co-authored-by: default avatarMadelyn Olson <34459052+madolson@users.noreply.github.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarYossi Gottlieb <yossigo@gmail.com>
      bda9d74d
  19. 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
  20. 16 Mar, 2022 1 commit
  21. 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
  22. 07 Mar, 2022 1 commit
  23. 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
  24. 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
  25. 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
  26. 26 Jan, 2022 1 commit
  27. 24 Jan, 2022 1 commit
  28. 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
  29. 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
  30. 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
  31. 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