1. 11 Mar, 2023 1 commit
    • guybe7's avatar
      Add reply_schema to command json files (internal for now) (#10273) · 4ba47d2d
      guybe7 authored
      Work in progress towards implementing a reply schema as part of COMMAND DOCS, see #9845
      Since ironing the details of the reply schema of each and every command can take a long time, we
      would like to merge this PR when the infrastructure is ready, and let this mature in the unstable branch.
      Meanwhile the changes of this PR are internal, they are part of the repo, but do not affect the produced build.
      
      ### Background
      In #9656 we add a lot of information about Redis commands, but we are missing information about the replies
      
      ### Motivation
      1. Documentation. This is the primary goal.
      2. It should be possible, based on the output of COMMAND, to be able to generate client code in typed
        languages. In order to do that, we need Redis to tell us, in detail, what each reply looks like.
      3. We would like to build a fuzzer that verifies the reply structure (for now we use the existing
        testsuite, see the "Testing" section)
      
      ### Schema
      The idea is to supply some sort of schema for the various replies of each command.
      The schema will describe the conceptual structure of the reply (for generated clients), as defined in RESP3.
      Note that the reply structure itself may change, depending on the arguments (e.g. `XINFO STREAM`, with
      and without the `FULL` modifier)
      We decided to use the standard json-schema (see https://json-schema.org/) as the reply-schema.
      
      Example for `BZPOPMIN`:
      ```
      "reply_schema": {
          "oneOf": [
              {
                  "description": "Timeout reached and no elements were popped.",
                  "type": "null"
              },
              {
                  "description": "The keyname, popped member, and its score.",
                  "type": "array",
                  "minItems": 3,
                  "maxItems": 3,
                  "items": [
                      {
                          "description": "Keyname",
                          "type": "string"
                      },
                      {
                          "description": "Member",
                          "type": "string"
                      },
                      {
                          "description": "Score",
                          "type": "number"
                      }
                  ]
              }
          ]
      }
      ```
      
      #### Notes
      1.  It is ok that some commands' reply structure depends on the arguments and it's the caller's responsibility
        to know which is the relevant one. this comes after looking at other request-reply systems like OpenAPI,
        where the reply schema can also be oneOf and the caller is responsible to know which schema is the relevant one.
      2. The reply schemas will describe RESP3 replies only. even though RESP3 is structured, we want to use reply
        schema for documentation (and possibly to create a fuzzer that validates the replies)
      3. For documentation, the description field will include an explanation of the scenario in which the reply is sent,
        including any relation to arguments. for example, for `ZRANGE`'s two schemas we will need to state that one
        is with `WITHSCORES` and the other is without.
      4. For documentation, there will be another optional field "notes" in which we will add a short description of
        the representation in RESP2, in case it's not trivial (RESP3's `ZRANGE`'s nested array vs. RESP2's flat
        array, for example)
      
      Given the above:
      1. We can generate the "return" section of all commands in [redis-doc](https://redis.io/commands/)
        (given that "description" and "notes" are comprehensive enough)
      2. We can generate a client in a strongly typed language (but the return type could be a conceptual
        `union` and the caller needs to know which schema is relevant). see the section below for RESP2 support.
      3. We can create a fuzzer for RESP3.
      
      ### Limitations (because we are using the standard json-schema)
      The problem is that Redis' replies are more diverse than what the json format allows. This means that,
      when we convert the reply to a json (in order to validate the schema against it), we lose information (see
      the "Testing" section below).
      The other option would have been to extend the standard json-schema (and json format) to include stuff
      like sets, bulk-strings, error-string, etc. but that would mean also extending the schema-validator - and that
      seemed like too much work, so we decided to compromise.
      
      Examples:
      1. We cannot tell the difference between an "array" and a "set"
      2. We cannot tell the difference between simple-string and bulk-string
      3. we cannot verify true uniqueness of items in commands like ZRANGE: json-schema doesn't cover the
        case of two identical members with different scores (e.g. `[["m1",6],["m1",7]]`) because `uniqueItems`
        compares (member,score) tuples and not just the member name. 
      
      ### Testing
      This commit includes some changes inside Redis in order to verify the schemas (existing and future ones)
      are indeed correct (i.e. describe the actual response of Redis).
      To do that, we added a debugging feature to Redis that causes it to produce a log of all the commands
      it executed and their replies.
      For that, Redis needs to be compiled with `-DLOG_REQ_RES` and run with
      `--reg-res-logfile <file> --client-default-resp 3` (the testsuite already does that if you run it with
      `--log-req-res --force-resp3`)
      You should run the testsuite with the above args (and `--dont-clean`) in order to make Redis generate
      `.reqres` files (same dir as the `stdout` files) which contain request-response pairs.
      These files are later on processed by `./utils/req-res-log-validator.py` which does:
      1. Goes over req-res files, generated by redis-servers, spawned by the testsuite (see logreqres.c)
      2. For each request-response pair, it validates the response against the request's reply_schema
        (obtained from the extended COMMAND DOCS)
      5. In order to get good coverage of the Redis commands, and all their different replies, we chose to use
        the existing redis test suite, rather than attempt to write a fuzzer.
      
      #### Notes about RESP2
      1. We will not be able to use the testing tool to verify RESP2 replies (we are ok with that, it's time to
        accept RESP3 as the future RESP)
      2. Since the majority of the test suite is using RESP2, and we want the server to reply with RESP3
        so that we can validate it, we will need to know how to convert the actual reply to the one expected.
         - number and boolean are always strings in RESP2 so the conversion is easy
         - objects (maps) are always a flat array in RESP2
         - others (nested array in RESP3's `ZRANGE` and others) will need some special per-command
           handling (so the client will not be totally auto-generated)
      
      Example for ZRANGE:
      ```
      "reply_schema": {
          "anyOf": [
              {
                  "description": "A list of member elements",
                  "type": "array",
                  "uniqueItems": true,
                  "items": {
                      "type": "string"
                  }
              },
              {
                  "description": "Members and their scores. Returned in case `WITHSCORES` was used.",
                  "notes": "In RESP2 this is returned as a flat array",
                  "type": "array",
                  "uniqueItems": true,
                  "items": {
                      "type": "array",
                      "minItems": 2,
                      "maxItems": 2,
                      "items": [
                          {
                              "description": "Member",
                              "type": "string"
                          },
                          {
                              "description": "Score",
                              "type": "number"
                          }
                      ]
                  }
              }
          ]
      }
      ```
      
      ### Other changes
      1. Some tests that behave differently depending on the RESP are now being tested for both RESP,
        regardless of the special log-req-res mode ("Pub/Sub PING" for example)
      2. Update the history field of CLIENT LIST
      3. Added basic tests for commands that were not covered at all by the testsuite
      
      ### TODO
      
      - [x] (maybe a different PR) add a "condition" field to anyOf/oneOf schemas that refers to args. e.g.
        when `SET` return NULL, the condition is `arguments.get||arguments.condition`, for `OK` the condition
        is `!arguments.get`, and for `string` the condition is `arguments.get` - https://github.com/redis/redis/issues/11896
      - [x] (maybe a different PR) also run `runtest-cluster` in the req-res logging mode
      - [x] add the new tests to GH actions (i.e. compile with `-DLOG_REQ_RES`, run the tests, and run the validator)
      - [x] (maybe a different PR) figure out a way to warn about (sub)schemas that are uncovered by the output
        of the tests - https://github.com/redis/redis/issues/11897
      - [x] (probably a separate PR) add all missing schemas
      - [x] check why "SDOWN is triggered by misconfigured instance replying with errors" fails with --log-req-res
      - [x] move the response transformers to their own file (run both regular, cluster, and sentinel tests - need to
        fight with the tcl including mechanism a bit)
      - [x] issue: module API - https://github.com/redis/redis/issues/11898
      - [x] (probably a separate PR): improve schemas: add `required` to `object`s - https://github.com/redis/redis/issues/11899
      
      Co-authored-by: default avatarOzan Tezcan <ozantezcan@gmail.com>
      Co-authored-by: default avatarHanna Fadida <hanna.fadida@redislabs.com>
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      Co-authored-by: default avatarShaya Potter <shaya@redislabs.com>
      4ba47d2d
  2. 18 Aug, 2022 1 commit
    • guybe7's avatar
      Repurpose redisCommandArg's name as the unique ID (#11051) · 223046ec
      guybe7 authored
      This PR makes sure that "name" is unique for all arguments in the same
      level (i.e. all args of a command and all args within a block/oneof).
      This means several argument with identical meaning can be referred to together,
      but also if someone needs to refer to a specific one, they can use its full path.
      
      In addition, the "display_text" field has been added, to be used by redis.io
      in order to render the syntax of the command (for the vast majority it is
      identical to "name" but sometimes we want to use a different string
      that is not "name")
      The "display" field is exposed via COMMAND DOCS and will be present
      for every argument, except "oneof" and "block" (which are container
      arguments)
      
      Other changes:
      1. Make sure we do not have any container arguments ("oneof" or "block")
         that contain less than two sub-args (otherwise it doesn't make sense)
      2. migrate.json: both AUTH and AUTH2 should not be "optional"
      3. arg names cannot contain underscores, and force the usage of hyphens
        (most of these were a result of the script that generated the initial json files
        from redis.io commands.json). 
      223046ec
  3. 05 Apr, 2022 1 commit
  4. 30 Jan, 2022 1 commit
    • Binbin's avatar
      Fix some wrong commands arguments since (#10208) · 21135471
      Binbin authored
      ZADD NX and XX was introduced in 3.0.2, not 6.2.0
      ZADD GT and LT was introduced in 6.2.0, not 3.0.2
      
      Add missing `COUNT ANY` history in georadius_ro
      Add missing `SHUTDOWN [NOW] [FORCE] [ABORT]` since in shutdown.json
      21135471
  5. 20 Jan, 2022 1 commit
    • 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
  6. 04 Jan, 2022 1 commit
    • guybe7's avatar
      Ban snapshot-creating commands and other admin commands from transactions (#10015) · ac84b1cd
      guybe7 authored
      
      
      Creating fork (or even a foreground SAVE) during a transaction breaks the atomicity of the transaction.
      In addition to that, it could mess up the propagated transaction to the AOF file.
      
      This change blocks SAVE, PSYNC, SYNC and SHUTDOWN from being executed inside MULTI-EXEC.
      It does that by adding a command flag, so that modules can flag their commands with that flag too.
      
      Besides it changes BGSAVE, BGREWRITEAOF, and CONFIG SET appendonly, to turn the
      scheduled flag instead of forking righ taway.
      
      Other changes:
      * expose `protected`, `no-async-loading`, and `no_multi` flags in COMMAND command
      * add a test to validate propagation of FLUSHALL inside a transaction.
      * add a test to validate how CONFIG SET that errors reacts in a transaction
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      ac84b1cd
  7. 02 Jan, 2022 1 commit
    • Viktor Söderqvist's avatar
      Wait for replicas when shutting down (#9872) · 45a155bd
      Viktor Söderqvist authored
      
      
      To avoid data loss, this commit adds a grace period for lagging replicas to
      catch up the replication offset.
      
      Done:
      
      * Wait for replicas when shutdown is triggered by SIGTERM and SIGINT.
      
      * Wait for replicas when shutdown is triggered by the SHUTDOWN command. A new
        blocked client type BLOCKED_SHUTDOWN is introduced, allowing multiple clients
        to call SHUTDOWN in parallel.
        Note that they don't expect a response unless an error happens and shutdown is aborted.
      
      * Log warning for each replica lagging behind when finishing shutdown.
      
      * CLIENT_PAUSE_WRITE while waiting for replicas.
      
      * Configurable grace period 'shutdown-timeout' in seconds (default 10).
      
      * New flags for the SHUTDOWN command:
      
          - NOW disables the grace period for lagging replicas.
      
          - FORCE ignores errors writing the RDB or AOF files which would normally
            prevent a shutdown.
      
          - ABORT cancels ongoing shutdown. Can't be combined with other flags.
      
      * New field in the output of the INFO command: 'shutdown_in_milliseconds'. The
        value is the remaining maximum time to wait for lagging replicas before
        finishing the shutdown. This field is present in the Server section **only**
        during shutdown.
      
      Not directly related:
      
      * When shutting down, if there is an AOF saving child, it is killed **even** if AOF
        is disabled. This can happen if BGREWRITEAOF is used when AOF is off.
      
      * Client pause now has end time and type (WRITE or ALL) per purpose. The
        different pause purposes are *CLIENT PAUSE command*, *failover* and
        *shutdown*. If clients are unpaused for one purpose, it doesn't affect client
        pause for other purposes. For example, the CLIENT UNPAUSE command doesn't
        affect client pause initiated by the failover or shutdown procedures. A completed
        failover or a failed shutdown doesn't unpause clients paused by the CLIENT
        PAUSE command.
      
      Notes:
      
      * DEBUG RESTART doesn't wait for replicas.
      
      * We already have a warning logged when a replica disconnects. This means that
        if any replica connection is lost during the shutdown, it is either logged as
        disconnected or as lagging at the time of exit.
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      45a155bd
  8. 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