1. 29 Mar, 2023 1 commit
    • Itamar Haber's avatar
      Overhauls command summaries and man pages. (#11942) · 0c3b8b7e
      Itamar Haber authored
      This is an attempt to normalize/formalize command summaries.
      
      Main actions performed:
      
      * Starts with the continuation of the phrase "The XXXX command, when called, ..." for user commands.
      * Starts with "An internal command...", "A container command...", etc... when applicable.
      * Always uses periods.
      * Refrains from referring to other commands. If this is needed, backquotes should be used for command names.
      * Tries to be very clear about the data type when applicable.
      * Tries to mention additional effects, e.g. "The key is created if it doesn't exist" and "The set is deleted if the last member is removed."
      * Prefers being terse over verbose.
      * Tries to be consistent.
      0c3b8b7e
  2. 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...
      4ba47d2d
  3. 24 Jan, 2022 1 commit
    • yoav-steinberg's avatar
      Support function flags in script EVAL via shebang header (#10126) · 7eadc5ee
      yoav-steinberg authored
      In #10025 we added a mechanism for flagging certain properties for Redis Functions.
      This lead us to think we'd like to "port" this mechanism to Redis Scripts (`EVAL`) as well. 
      
      One good reason for this, other than the added functionality is because it addresses the
      poor behavior we currently have in `EVAL` in case the script performs a (non DENY_OOM) write operation
      during OOM state. See #8478 (And a previous attempt to handle it via #10093) for details.
      Note that in Redis Functions **all** write operations (including DEL) will return an error during OOM state
      unless the function is flagged as `allow-oom` in which case no OOM checking is performed at all.
      
      This PR:
      - Enables setting `EVAL` (and `SCRIPT LOAD`) script flags as defined in #10025.
      - Provides a syntactical framework via [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) for
        additional script annotations and even engine selection (instead of just lua) for scripts.
      - Provides backwards compatibility so scripts without the new annotations will behave as they did before.
      - Appropriate tests.
      - Changes `EVAL[SHA]/_RO` to be flagged as `STALE` commands. This makes it possible to flag individual
        scripts as `allow-stale` or not flag them as such. In backwards compatibility mode these commands will
        return the `MASTERDOWN` error as before.
      - Changes `SCRIPT LOAD` to be flagged as a `STALE` command. This is mainly to make it logically
        compatible with the change to `EVAL` in the previous point. It enables loading a script on a stale server
        which is technically okay it doesn't relate directly to the server's dataset. Running the script does, but that
        won't work unless the script is explicitly marked as `allow-stale`.
      
      Note that even though the LUA syntax doesn't support hash tag comments `.lua` files do support a shebang
      tag on the top so they can be executed on Unix systems like any shell script. LUA's `luaL_loadfile` handles
      this as part of the LUA library. In the case of `luaL_loadbuffer`, which is what Redis uses, I needed to fix the
      input script in case of a shebang manually. I did this the same way `luaL_loadfile` does, by replacing the
      first line with a single line feed character.
      7eadc5ee
  4. 20 Jan, 2022 1 commit
    • guybe7's avatar
      Add command tips to COMMAND DOCS (#10104) · 10bbeb68
      guybe7 authored
      Adding command tips (see https://redis.io/topics/command-tips) to commands.
      
      Breaking changes:
      1. Removed the "random" and "sort_for_script" flags. They are now command tips.
      (this isn't affecting redis behavior since #9812, but could affect some client applications
      that's relying on COMMAND command flags)
      
      Summary of changes:
      1. add BLOCKING flag (new flag) for all commands that could block. The ACL category with
        the same name is now implicit.
      2. move RANDOM flag to a `nondeterministic_output` tip
      3. move SORT_FOR_SCRIPT flag to `nondeterministic_output_order` tip
      3. add REQUEST_POLICY and RESPONSE_POLICY where appropriate as documented in the tips
      4. deprecate (ignore) the `random` flag for RM_CreateCommand
      
      Other notes:
      1. Proxies need to send `RANDOMKEY` to all shards and then select one key randomly.
        The other option is to pick a random shard and transfer `RANDOMKEY `to it, but that scheme
        fails if this specific shard is empty
      2. Remove CMD_RANDOM from `XACK` (i.e. XACK does not have RANDOM_OUTPUT)
         It was added in 9e4fb96c, I guess by mistake.
         Also from `(P)EXPIRETIME` (new command, was flagged "random" by mistake).
      3. Add `nondeterministic_output` to `OBJECT ENCODING` (for the same reason `XTRIM` has it:
         the reply may differ depending on the internal representation in memory)
      4. RANDOM on `HGETALL` was wrong (there due to a limitation of the old script sorting logic), now
        it's `nondeterministic_output_order`
      5. Unrelated: Hide CMD_PROTECTED from COMMAND
      10bbeb68
  5. 21 Dec, 2021 1 commit
    • zhugezy's avatar
      Remove EVAL script verbatim replication, propagation, and deterministic execution logic (#9812) · 1b0968df
      zhugezy authored
      
      
      # Background
      
      The main goal of this PR is to remove relevant logics on Lua script verbatim replication,
      only keeping effects replication logic, which has been set as default since Redis 5.0.
      As a result, Lua in Redis 7.0 would be acting the same as Redis 6.0 with default
      configuration from users' point of view.
      
      There are lots of reasons to remove verbatim replication.
      Antirez has listed some of the benefits in Issue #5292:
      
      >1. No longer need to explain to users side effects into scripts.
          They can do whatever they want.
      >2. No need for a cache about scripts that we sent or not to the slaves.
      >3. No need to sort the output of certain commands inside scripts
          (SMEMBERS and others): this both simplifies and gains speed.
      >4. No need to store scripts inside the RDB file in order to startup correctly.
      >5. No problems about evicting keys during the script execution.
      
      When looking back at Redis 5.0, antirez and core team decided to set the config
      `lua-replicate-commands yes` by default instead of removing verbatim replication
      directly, in case some bad situations happened. 3 years later now before Redis 7.0,
      it's time to remove it formally.
      
      # Changes
      
      - configuration for lua-replicate-commands removed
        - created config file stub for backward compatibility
      - Replication script cache removed
        - this is useless under script effects replication
        - relevant statistics also removed
      - script persistence in RDB files is also removed
      - Propagation of SCRIPT LOAD and SCRIPT FLUSH to replica / AOF removed
      - Deterministic execution logic in scripts removed (i.e. don't run write commands
        after random ones, and sorting output of commands with random order)
        - the flags indicating which commands have non-deterministic results are kept as hints to clients.
      - `redis.replicate_commands()` & `redis.set_repl()` changed
        - now `redis.replicate_commands()` does nothing and return an 1
        - ...and then `redis.set_repl()` can be issued before `redis.replicate_commands()` now
      - Relevant TCL cases adjusted
      - DEBUG lua-always-replicate-commands removed
      
      # Other changes
      - Fix a recent bug comparing CLIENT_ID_AOF to original_client->flags instead of id. (introduced in #9780)
      Co-authored-by: default avatarOran Agra <oran@redislabs.com>
      1b0968df
  6. 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, ...
      86781600