Commit Graph

44 Commits

Author SHA1 Message Date
Wen Hui
de6be8850f
Fix PUBSUB SHARDNUMSUB command json file (#10331)
argument was missing, affecting redis.io docs
2022-02-22 23:29:29 +02:00
Madelyn Olson
71204f9632
Implemented module getchannels api and renamed channel keyspec (#10299)
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.
2022-02-22 11:00:03 +02:00
Binbin
c4c68f5d41
Remove ALLOW_BUSY from REPLICAOF and add it to REPLCONF. Add DEPRECATED doc flag to SLAVEOF, mark it as deprecated. (#10315)
* Remove ALLOW_BUSY from REPLICAOF and add it to REPLCONF
* mark SLAVEOF as deprecated
2022-02-22 10:55:54 +02:00
yoav-steinberg
b59bb9b476
Fix script active defrag test (#10318)
This includes two fixes:
* We forgot to count non-key reallocs in defragmentation stats.
* Fix the script defrag tests so to make dict entries less signigicant in fragmentation by making the scripts larger.
This assures active defrage will complete and reach desired results.
Some inherent fragmentation might exists in dict entries which we need to ignore.
This lead to occasional CI failures.
2022-02-21 09:37:25 +02:00
Wen Hui
2e1bc942aa
Make INFO command variadic (#6891)
This is an enhancement for INFO command, previously INFO only support one argument
for different info section , if user want to get more categories information, either perform
INFO all / default or calling INFO for multiple times.

**Description of the feature**

The goal of adding this feature is to let the user retrieve multiple categories via the INFO
command, and still avoid emitting the same section twice.

A use case for this is like Redis Sentinel, which periodically calling INFO command to refresh
info from monitored Master/Slaves, only Server and Replication part categories are used for
parsing information. If the INFO command can return just enough categories that client side
needs, it can save a lot of time for client side parsing it as well as network bandwidth.

**Implementation**
To share code between redis, sentinel, and other users of INFO (DEBUG and modules),
we have a new `genInfoSectionDict` function that returns a dict and some boolean flags
(e.g. `all`) to the caller (built from user input).
Sentinel is later purging unwanted sections from that, and then it is forwarded to the info `genRedisInfoString`.

**Usage Examples**
INFO Server Replication   
INFO CPU Memory
INFO default commandstats

Co-authored-by: Oran Agra <oran@redislabs.com>
2022-02-08 13:14:42 +02:00
guybe7
3c3e6cc1c7
X[AUTO]CLAIM should skip deleted entries (#10227)
Fix #7021 #8924 #10198

# Intro
Before this commit X[AUTO]CLAIM used to transfer deleted entries from one
PEL to another, but reply with "nil" for every such entry (instead of the entry id).
The idea (for XCLAIM) was that the caller could see this "nil", realize the entry
no longer exists, and XACK it in order to remove it from PEL.
The main problem with that approach is that it assumes there's a correlation
between the index of the "id" arguments and the array indices, which there
isn't (in case some of the input IDs to XCLAIM never existed/read):

```
127.0.0.1:6379> XADD x 1 f1 v1
"1-0"
127.0.0.1:6379> XADD x 2 f1 v1
"2-0"
127.0.0.1:6379> XADD x 3 f1 v1
"3-0"
127.0.0.1:6379> XGROUP CREATE x grp 0
OK
127.0.0.1:6379> XREADGROUP GROUP grp Alice COUNT 2 STREAMS x >
1) 1) "x"
   2) 1) 1) "1-0"
         2) 1) "f1"
            2) "v1"
      2) 1) "2-0"
         2) 1) "f1"
            2) "v1"
127.0.0.1:6379> XDEL x 1 2
(integer) 2
127.0.0.1:6379> XCLAIM x grp Bob 0 0-99 1-0 1-99 2-0
1) (nil)
2) (nil)
```

# Changes
Now,  X[AUTO]CLAIM acts in the following way:
1. If one tries to claim a deleted entry, we delete it from the PEL we found it in
  (and the group PEL too). So de facto, such entry is not claimed, just cleared
  from PEL (since anyway it doesn't exist in the stream)
2. since we never claim deleted entries, X[AUTO]CLAIM will never return "nil"
  instead of an entry.
3. add a new element to XAUTOCLAIM's response (see below)

# Knowing which entries were cleared from the PEL
The caller may want to log any entries that were found in a PEL but deleted from
the stream itself (it would suggest that there might be a bug in the application:
trimming the stream while some entries were still no processed by the consumers)

## XCLAIM
the set {XCLAIM input ids} - {XCLAIM returned ids} contains all the entry ids that were
not claimed which means they were deleted (assuming the input contains only entries
from some PEL). The user doesn't need to XACK them because XCLAIM had already
deleted them from the source PEL.

## XAUTOCLAIM
XAUTOCLAIM has a new element added to its reply: it's an array of all the deleted
stream IDs it stumbled upon.

This is somewhat of a breaking change since X[AUTO]CLAIM used to be able to reply
with "nil" and now it can't... But since it was undocumented (and generally a bad idea
to rely on it, as explained above) the breakage is not that bad.
2022-02-08 10:20:09 +02:00
Oran Agra
66be30f7fc
Handle key-spec flags with modules (#10237)
- 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
2022-02-08 10:01:35 +02:00
Binbin
b95beeb595
Fix redis-cli with sentinel crash due to SENTINEL DEBUG missing summary (#10250)
Fix redis-cli with sentinel crash due to SENTINEL DEBUG missing summary

Because SENTINEL DEBUG missing summary in its json file,
with the change in #10043, the following assertion will fail.
```
[redis]# src/redis-cli -p 26379
redis-cli: redis-cli.c:678: cliInitCommandHelpEntry: Assertion `reply->type == 1' failed.
```

This commit add the summary and complexity for SENTINEL DEBUG,
which introduced in #9291, and also improved the help message.
2022-02-07 13:27:33 +02:00
Binbin
e662f6835e
Update FCALL/FCALL_RO summary and complexity (#10240)
1. Update fcall.json and fcall_ro.json
2. Update command.c
3. Update help.h
2022-02-05 10:35:07 +02:00
Meir Shpilraien (Spielrein)
8eb19cc251
update function help message, changed DESC->DESCRIPTION. (#10228)
update function help message, changed DESC->DESCRIPTION (doc was outdated)
2022-02-02 15:50:41 +02:00
Madelyn Olson
d0bc4fff18
Added history for cluster-slots changes for hostnames(#10216)
* The first field was previously only an IP address, it can now be a hostname or NULL.
* There is now a fourth field, which has more information.
2022-01-30 23:57:10 -08:00
guybe7
eedec155ac
Add key-specs notes (#10193)
Add optional `notes` to keyspecs.

Other changes:

1. Remove the "incomplete" flag from SORT and SORT_RO: it is misleading since "incomplete" means "this spec may not return all the keys it describes" but SORT and SORT_RO's specs (except the input key) do not return any keys at all.
So basically:
If a spec's begin_search is "unknown" you should not use it at all, you must use COMMAND KEYS;
if a spec itself is "incomplete", you can use it to get a partial list of keys, but if you want all of them you must use COMMAND GETKEYS;
otherwise, the spec will return all the keys

2. `getKeysUsingKeySpecs` handles incomplete specs internally
2022-01-30 12:00:03 +02:00
Binbin
21135471a6
Fix some wrong commands arguments since (#10208)
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
2022-01-30 08:45:12 +02:00
Binbin
93d951556b
commands arguments improvement about unix-time type (#10203)
Change the name to unix-time-seconds or unix-time-milliseconds
to be consistent. Change the type from INTEGER to UNIX_TIME.

SET (EXAT and PXAT) was already ok.
and naming aside, both PXAT and EXAT everywhere used unit-time (for both milliseconds and seconds).
the only ones that where wrong are GETEX and XCLAIM (using "integer" for both seconds and milliseconds)
2022-01-29 15:21:59 +02:00
Binbin
d616925835
Allow SET without GET arg on write-only ACL. Allow BITFIELD GET on read-only ACL (#10148)
SET is a R+W command, because it can also do `GET` on the data.
SET without GET is a write-only command.
SET with GET is a read+write command.

In #9974, we added ACL to let users define write-only access.
So when the user uses SET with GET option, and the user doesn't
have the READ permission on the key, we need to reject it,
but we rather not reject users with write-only permissions from using
the SET command when they don't use GET.

In this commit, we add a `getkeys_proc` function to control key
flags in SET command. We also add a new key spec flag (VARIABLE_FLAGS)
means that some keys might have different flags depending on arguments.

We also handle BITFIELD command, add a `bitfieldGetKeys` function.
BITFIELD GET is a READ ONLY command.
BITFIELD SET or BITFIELD INCR are READ WRITE commands.

Other changes:
1. SET GET was added in 6.2, add the missing since in set.json
2. Added tests to cover the changes in acl-v2.tcl
3. Fix some typos in server.h and cleanups in acl-v2.tcl

Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
2022-01-26 21:03:21 +02:00
Madelyn Olson
823da54361
Improve testing and update flags around commands without ACL keyspec flags (#10167)
This PR aims to improve the flags associated with some commands and adds various tests around
these cases. Specifically, it's concerned with commands which declare keys but have no ACL
flags (think `EXISTS`), the user needs either read or write permission to access this type of key.

This change is primarily concerned around commands in three categories:

# General keyspace commands
These commands are agnostic to the underlying data outside of side channel attacks, so they are not
marked as ACCESS.
* TOUCH
* EXISTS
* TYPE
* OBJECT 'all subcommands'

Note that TOUCH is not a write command, it could be a side effect of either a read or a write command.

# Length and cardinality commands
These commands are marked as NOT marked as ACCESS since they don't return actual user strings,
just metadata.
* LLEN
* STRLEN
* SCARD
* HSTRLEN

# Container has member commands
These commands return information about the existence or metadata about the key. These commands
are NOT marked as ACCESS since the check of membership is used widely in write commands
e.g. the response of HSET. 
* SISMEMBER
* HEXISTS

# Intersection cardinality commands
These commands are marked as ACCESS since they process data to compute the result.
* PFCOUNT
* ZCOUNT
* ZINTERCARD
* SINTERCARD
2022-01-25 09:55:30 +02:00
yoav-steinberg
7eadc5ee70
Support function flags in script EVAL via shebang header (#10126)
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.
2022-01-24 16:50:02 +02:00
Madelyn Olson
55c81f2cd3
ACL V2 - Selectors and key based permissions (#9974)
* 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: Oran Agra <oran@redislabs.com>
2022-01-20 13:05:27 -08:00
guybe7
10bbeb6837
Add command tips to COMMAND DOCS (#10104)
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 9e4fb96ca1, 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
2022-01-20 11:32:11 +02:00
perryitay
c4b788230c
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: Oran Agra <oran@redislabs.com>
2022-01-20 09:05:53 +02:00
Madelyn Olson
22172a4aa6
Fix double key declaration for renamenx and change flag to INSERT (#10137)
* Fix double key declaration for renamenx
* Change the flag from UPDATE to INSERT, since it can not affect the data in the key
2022-01-19 19:30:32 -08:00
Binbin
3720de78c9
Fix fcall_ro key spec flags in commands.c (#10145)
In #10122, we modify the key spec flags to `RO` and `ACCESS`.
But forgot to call generate-command-code.py. Also formatted
it to follow the Python PEP8.
2022-01-19 16:07:28 +02:00
Oran Agra
eef9c6b0ee
New detailed key-spec flags (RO, RW, OW, RM, ACCESS, UPDATE, INSERT, DELETE) (#10122)
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
2022-01-18 16:00:00 +02:00
Ali-Akber Saifee
98414aca7f
Fix typo in doc for PUBSUB command (#10117)
Replace "Pub/Sun" -> "Pub/Sub"
2022-01-15 19:57:24 +02:00
Meir Shpilraien (Spielrein)
4db4b43417
Function Flags support (no-writes, no-cluster, allow-state, allow-oom) (#10066)
# Redis Functions Flags

Following the discussion on #10025 Added Functions Flags support.
The PR is divided to 2 sections:
* Add named argument support to `redis.register_function` API.
* Add support for function flags

## `redis.register_function` named argument support

The first part of the PR adds support for named argument on `redis.register_function`, example:
```
redis.register_function{
    function_name='f1',
    callback=function()
        return 'hello'
    end,
    description='some desc'
}
```

The positional arguments is also kept, which means that it still possible to write:
```
redis.register_function('f1', function() return 'hello' end)
```

But notice that it is no longer possible to pass the optional description argument on the positional
argument version. Positional argument was change to allow passing only the mandatory arguments
(function name and callback). To pass more arguments the user must use the named argument version.

As with positional arguments, the `function_name` and `callback` is mandatory and an error will be
raise if those are missing. Also, an error will be raise if an unknown argument name is given or the
arguments type is wrong.

Tests was added to verify the new syntax.

## Functions Flags

The second part of the PR is adding functions flags support.
Flags are given to Redis when the engine calls `functionLibCreateFunction`, supported flags are:

* `no-writes` - indicating the function perform no writes which means that it is OK to run it on:
   * read-only replica
   * Using FCALL_RO
   * If disk error detected
   
   It will not be possible to run a function in those situations unless the function turns on the `no-writes` flag

* `allow-oom` - indicate that its OK to run the function even if Redis is in OOM state, if the function will
  not turn on this flag it will not be possible to run it if OOM reached (even if the function declares `no-writes`
  and even if `fcall_ro` is used). If this flag is set, any command will be allow on OOM (even those that is
  marked with CMD_DENYOOM). The assumption is that this flag is for advance users that knows its
  meaning and understand what they are doing, and Redis trust them to not increase the memory usage.
  (e.g. it could be an INCR or a modification on an existing key, or a DEL command)

* `allow-state` - indicate that its OK to run the function on stale replica, in this case we will also make
  sure the function is only perform `stale` commands and raise an error if not.

* `no-cluster` - indicate to disallow running the function if cluster is enabled.

Default behaviure of functions (if no flags is given):
1. Allow functions to read and write
2. Do not run functions on OOM
3. Do not run functions on stale replica
4. Allow functions on cluster

### Lua API for functions flags

On Lua engine, it is possible to give functions flags as `flags` named argument:

```
redis.register_function{function_name='f1', callback=function() return 1 end, flags={'no-writes', 'allow-oom'}, description='description'}
```

The function flags argument must be a Lua table that contains all the requested flags, The following
will result in an error:
* Unknown flag
* Wrong flag type

Default behaviour is the same as if no flags are used.

Tests were added to verify all flags functionality

## Additional changes
* mark FCALL and FCALL_RO with CMD_STALE flag (unlike EVAL), so that they can run if the function was
  registered with the `allow-stale` flag.
* Verify `CMD_STALE` on `scriptCall` (`redis.call`), so it will not be possible to call commands from script while
  stale unless the command is marked with the `CMD_STALE` flags. so that even if the function is allowed while
  stale we do not allow it to bypass the `CMD_STALE` flag of commands.
* Flags section was added to `FUNCTION LIST` command to provide the set of flags for each function:
```
> FUNCTION list withcode
1)  1) "library_name"
    2) "test"
    3) "engine"
    4) "LUA"
    5) "description"
    6) (nil)
    7) "functions"
    8) 1) 1) "name"
          2) "f1"
          3) "description"
          4) (nil)
          5) "flags"
          6) (empty array)
    9) "library_code"
   10) "redis.register_function{function_name='f1', callback=function() return 1 end}"
```
* Added API to get Redis version from within a script, The redis version can be provided using:
   1. `redis.REDIS_VERSION` - string representation of the redis version in the format of MAJOR.MINOR.PATH
   2. `redis.REDIS_VERSION_NUM` - number representation of the redis version in the format of `0x00MMmmpp`
      (`MM` - major, `mm` - minor,  `pp` - patch). The number version can be used to check if version is greater or less 
      another version. The string version can be used to return to the user or print as logs.

   This new API is provided to eval scripts and functions, it also possible to use this API during functions loading phase.
2022-01-14 14:02:02 +02:00
Oran Agra
3204a03574
Move doc metadata from COMMAND to COMMAND DOCS (#10056)
Syntax:
`COMMAND DOCS [<command name> ...]`

Background:
Apparently old version of hiredis (and thus also redis-cli) can't
support more than 7 levels of multi-bulk nesting.

The solution is to move all the doc related metadata from COMMAND to a
new COMMAND DOCS sub-command.

The new DOCS sub-command returns a map of commands (not an array like in COMMAND),
And the same goes for the `subcommands` field inside it (also contains a map)

Besides that, the remaining new fields of COMMAND (hints, key-specs, and
sub-commands), are placed in the outer array rather than a nested map.
this was done mainly for consistency with the old format.

Other changes:
---
* Allow COMMAND INFO with no arguments, which returns all commands, so that we can some day deprecated
  the plain COMMAND (no args)

* Reduce the amount of deferred replies from both COMMAND and COMMAND
  DOCS, especially in the inner loops, since these create many small
  reply objects, which lead to many small write syscalls and many small
  TCP packets.
  To make this easier, when populating the command table, we count the
  history, args, and hints so we later know their size in advance.
  Additionally, the movablekeys flag was moved into the flags register.
* Update generate-commands-json.py to take the data from both command, it
  now executes redis-cli directly, instead of taking input from stdin.
* Sub-commands in both COMMAND (and COMMAND INFO), and also COMMAND DOCS,
  show their full name. i.e. CONFIG 
*   GET will be shown as `config|get` rather than just `get`.
  This will be visible both when asking for `COMMAND INFO config` and COMMAND INFO config|get`, but is
  especially important for the later.
  i.e. imagine someone doing `COMMAND INFO slowlog|get config|get` not being able to distinguish between the two
  items in the array response.
2022-01-11 17:16:16 +02:00
Wen Hui
d7479107c7
update codes according to new json file (#7425)
readonly/readwrite only set client flags for slave in cluster mode,
so it should be ok for setting ok-stale and ok-loading command flag
2022-01-10 08:00:04 +02:00
Itamar Haber
75c50a1563
Fixes 'since' for GEORADIUS[BYMEMBER]_RO (#10034) 2022-01-09 11:13:32 +02:00
Meir Shpilraien (Spielrein)
885f6b5ceb
Redis Function Libraries (#10004)
# Redis Function Libraries

This PR implements Redis Functions Libraries as describe on: https://github.com/redis/redis/issues/9906.

Libraries purpose is to provide a better code sharing between functions by allowing to create multiple
functions in a single command. Functions that were created together can safely share code between
each other without worrying about compatibility issues and versioning.

Creating a new library is done using 'FUNCTION LOAD' command (full API is described below)

This PR introduces a new struct called libraryInfo, libraryInfo holds information about a library:
* name - name of the library
* engine - engine used to create the library
* code - library code
* description - library description
* functions - the functions exposed by the library

When Redis gets the `FUNCTION LOAD` command it creates a new empty libraryInfo.
Redis passes the `CODE` to the relevant engine alongside the empty libraryInfo.
As a result, the engine will create one or more functions by calling 'libraryCreateFunction'.
The new funcion will be added to the newly created libraryInfo. So far Everything is happening
locally on the libraryInfo so it is easy to abort the operation (in case of an error) by simply
freeing the libraryInfo. After the library info is fully constructed we start the joining phase by
which we will join the new library to the other libraries currently exist on Redis.
The joining phase make sure there is no function collision and add the library to the
librariesCtx (renamed from functionCtx). LibrariesCtx is used all around the code in the exact
same way as functionCtx was used (with respect to RDB loading, replicatio, ...).
The only difference is that apart from function dictionary (maps function name to functionInfo
object), the librariesCtx contains also a libraries dictionary that maps library name to libraryInfo object.

## New API
### FUNCTION LOAD
`FUNCTION LOAD <ENGINE> <LIBRARY NAME> [REPLACE] [DESCRIPTION <DESCRIPTION>] <CODE>`
Create a new library with the given parameters:
* ENGINE - REPLACE Engine name to use to create the library.
* LIBRARY NAME - The new library name.
* REPLACE - If the library already exists, replace it.
* DESCRIPTION - Library description.
* CODE - Library code.

Return "OK" on success, or error on the following cases:
* Library name already taken and REPLACE was not used
* Name collision with another existing library (even if replace was uses)
* Library registration failed by the engine (usually compilation error)

## Changed API
### FUNCTION LIST
`FUNCTION LIST [LIBRARYNAME <LIBRARY NAME PATTERN>] [WITHCODE]`
Command was modified to also allow getting libraries code (so `FUNCTION INFO` command is no longer
needed and removed). In addition the command gets an option argument, `LIBRARYNAME` allows you to
only get libraries that match the given `LIBRARYNAME` pattern. By default, it returns all libraries.

### INFO MEMORY
Added number of libraries to `INFO MEMORY`

### Commands flags
`DENYOOM` flag was set on `FUNCTION LOAD` and `FUNCTION RESTORE`. We consider those commands
as commands that add new data to the dateset (functions are data) and so we want to disallows
to run those commands on OOM.

## Removed API
* FUNCTION CREATE - Decided on https://github.com/redis/redis/issues/9906
* FUNCTION INFO - Decided on https://github.com/redis/redis/issues/9899

## Lua engine changes
When the Lua engine gets the code given on `FUNCTION LOAD` command, it immediately runs it, we call
this run the loading run. Loading run is not a usual script run, it is not possible to invoke any
Redis command from within the load run.
Instead there is a new API provided by `library` object. The new API's: 
* `redis.log` - behave the same as `redis.log`
* `redis.register_function` - register a new function to the library

The loading run purpose is to register functions using the new `redis.register_function` API.
Any attempt to use any other API will result in an error. In addition, the load run is has a time
limit of 500ms, error is raise on timeout and the entire operation is aborted.

### `redis.register_function`
`redis.register_function(<function_name>, <callback>, [<description>])`
This new API allows users to register a new function that will be linked to the newly created library.
This API can only be called during the load run (see definition above). Any attempt to use it outside
of the load run will result in an error.
The parameters pass to the API are:
* function_name - Function name (must be a Lua string)
* callback - Lua function object that will be called when the function is invokes using fcall/fcall_ro
* description - Function description, optional (must be a Lua string).

### Example
The following example creates a library called `lib` with 2 functions, `f1` and `f1`, returns 1 and 2 respectively:
```
local function f1(keys, args)
    return 1
end

local function f2(keys, args)
    return 2
end

redis.register_function('f1', f1)
redis.register_function('f2', f2)
```

Notice: Unlike `eval`, functions inside a library get the KEYS and ARGV as arguments to the
functions and not as global.

### Technical Details

On the load run we only want the user to be able to call a white list on API's. This way, in
the future, if new API's will be added, the new API's will not be available to the load run
unless specifically added to this white list. We put the while list on the `library` object and
make sure the `library` object is only available to the load run by using [lua_setfenv](https://www.lua.org/manual/5.1/manual.html#lua_setfenv) API. This API allows us to set
the `globals` of a function (and all the function it creates). Before starting the load run we
create a new fresh Lua table (call it `g`) that only contains the `library` API (we make sure
to set global protection on this table just like the general global protection already exists
today), then we use [lua_setfenv](https://www.lua.org/manual/5.1/manual.html#lua_setfenv)
to set `g` as the global table of the load run. After the load run finished we update `g`
metatable and set `__index` and `__newindex` functions to be `_G` (Lua default globals),
we also pop out the `library` object as we do not need it anymore.
This way, any function that was created on the load run (and will be invoke using `fcall`) will
see the default globals as it expected to see them and will not have the `library` API anymore.

An important outcome of this new approach is that now we can achieve a distinct global table
for each library (it is not yet like that but it is very easy to achieve it now). In the future we can
decide to remove global protection because global on different libraries will not collide or we
can chose to give different API to different libraries base on some configuration or input.

Notice that this technique was meant to prevent errors and was not meant to prevent malicious
user from exploit it. For example, the load run can still save the `library` object on some local
variable and then using in `fcall` context. To prevent such a malicious use, the C code also make
sure it is running in the right context and if not raise an error.
2022-01-06 13:39:38 +02:00
filipe oliveira
5dd15443ac
Added INFO LATENCYSTATS section: latency by percentile distribution/latency by cumulative distribution of latencies (#9462)
# Short description

The Redis extended latency stats track per command latencies and enables:
- exporting the per-command percentile distribution via the `INFO LATENCYSTATS` command.
  **( percentile distribution is not mergeable between cluster nodes ).**
- exporting the per-command cumulative latency distributions via the `LATENCY HISTOGRAM` command.
  Using the cumulative distribution of latencies we can merge several stats from different cluster nodes
  to calculate aggregate metrics .

By default, the extended latency monitoring is enabled since the overhead of keeping track of the
command latency is very small.
 
If you don't want to track extended latency metrics, you can easily disable it at runtime using the command:
 - `CONFIG SET latency-tracking no`

By default, the exported latency percentiles are the p50, p99, and p999.
You can alter them at runtime using the command:
- `CONFIG SET latency-tracking-info-percentiles "0.0 50.0 100.0"`


## Some details:
- The total size per histogram should sit around 40 KiB. We only allocate those 40KiB when a command
  was called for the first time.
- With regards to the WRITE overhead As seen below, there is no measurable overhead on the achievable
  ops/sec or full latency spectrum on the client. Including also the measured redis-benchmark for unstable
  vs this branch. 
- We track from 1 nanosecond to 1 second ( everything above 1 second is considered +Inf )

## `INFO LATENCYSTATS` exposition format

   - Format: `latency_percentiles_usec_<CMDNAME>:p0=XX,p50....` 

## `LATENCY HISTOGRAM [command ...]` exposition format

Return a cumulative distribution of latencies in the format of a histogram for the specified command names.

The histogram is composed of a map of time buckets:
- Each representing a latency range, between 1 nanosecond and roughly 1 second.
- Each bucket covers twice the previous bucket's range.
- Empty buckets are not printed.
- Everything above 1 sec is considered +Inf.
- At max there will be log2(1000000000)=30 buckets

We reply a map for each command in the format:
`<command name> : { `calls`: <total command calls> , `histogram` : { <bucket 1> : latency , < bucket 2> : latency, ...  } }`

Co-authored-by: Oran Agra <oran@redislabs.com>
2022-01-05 14:01:05 +02:00
guybe7
ac84b1cd82
Ban snapshot-creating commands and other admin commands from transactions (#10015)
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: Oran Agra <oran@redislabs.com>
2022-01-04 13:37:47 +02:00
Harkrishn Patro
9f8885760b
Sharded pubsub implementation (#8621)
This commit implements a sharded pubsub implementation based off of shard channels.

Co-authored-by: Harkrishn Patro <harkrisp@amazon.com>
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
2022-01-02 16:54:47 -08:00
Viktor Söderqvist
45a155bd0f
Wait for replicas when shutting down (#9872)
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: Oran Agra <oran@redislabs.com>
2022-01-02 09:50:15 +02:00
Itamar Haber
aec8c57701
Add missing metadata to the commands SSOT files. (#10016)
Add missing information about commands, mainly from reviewing redis-doc and removing
the metadata from it (https://github.com/redis/redis-doc/pull/1722)

* Reintroduces CLUSTER S****S (supported by Redis) but missing from the JSON / docs (related? #9675).
  Note that without that json file, the command won't work (breaking change)
* Adds the `replicas` argument (exists in Redis) to `CLIENT KILL`.
* Adds `history` entries to several commands based on redis-doc's man pages.
* Adds `since` to applicable command arguments based on `history` (this basically makes
  some of `history` redundant - perhaps at a later stage).
* Uses proper semantic versioning in all version references.
* Also removes `geoencodeCommand` and `geodecodeCommand` header
  declarations per b96af595a5.
2021-12-29 21:57:40 +02:00
Meir Shpilraien (Spielrein)
365cbf46a7
Add FUNCTION DUMP and RESTORE. (#9938)
Follow the conclusions to support Functions in redis cluster (#9899)

Added 2 new FUNCTION sub-commands:
1. `FUNCTION DUMP` - dump a binary payload representation of all the functions.
2. `FUNCTION RESTORE <PAYLOAD> [FLUSH|APPEND|REPLACE]` - give the binary payload extracted
   using `FUNCTION DUMP`, restore all the functions on the given payload. Restore policy can be given to
   control how to handle existing functions (default is APPEND):
   * FLUSH: delete all existing functions.
   * APPEND: appends the restored functions to the existing functions. On collision, abort.
   * REPLACE: appends the restored functions to the existing functions. On collision,
     replace the old function with the new function.

Modify `redis-cli --cluster add-node` to use `FUNCTION DUMP` to get existing functions from
one of the nodes in the cluster, and `FUNCTION RESTORE` to load the same set of functions
to the new node. `redis-cli` will execute this step before sending the `CLUSTER MEET` command
to the new node. If `FUNCTION DUMP` returns an error, assume the current Redis version do not
support functions and skip `FUNCTION RESTORE`. If `FUNCTION RESTORE` fails, abort and do not send
the `CLUSTER MEET` command. If the new node already contains functions (before the `FUNCTION RESTORE`
is sent), abort and do not add the node to the cluster. Test was added to verify
`redis-cli --cluster add-node` works as expected.
2021-12-26 09:03:37 +02:00
Oran Agra
41e6e05dee
Allow most CONFIG SET during loading, block some commands in async-loading (#9878)
## background
Till now CONFIG SET was blocked during loading.
(In the not so distant past, GET was disallowed too)

We recently (not released yet) added an async-loading mode, see #9323,
and during that time it'll serve CONFIG SET and any other command.
And now we realized (#9770) that some configs, and commands are dangerous
during async-loading.

## changes
* Allow most CONFIG SET during loading (both on async-loading and normal loading)
* Allow CONFIG REWRITE and CONFIG RESETSTAT during loading
* Block a few config during loading (`appendonly`, `repl-diskless-load`, and `dir`)
* Block a few commands during loading (list below)

## the blocked commands:
* SAVE - obviously we don't wanna start a foregreound save during loading 8-)
* BGSAVE - we don't mind to schedule one, but we don't wanna fork now
* BGREWRITEAOF - we don't mind to schedule one, but we don't wanna fork now
* MODULE - we obviously don't wanna unload a module during replication / rdb loading
  (MODULE HELP and MODULE LIST are not blocked)
* SYNC / PSYNC - we're in the middle of RDB loading from master, must not allow sync
  requests now.
* REPLICAOF / SLAVEOF - we're in the middle of replicating, maybe it makes sense to let
  the user abort it, but he couldn't do that so far, i don't wanna take any risk of bugs due to odd state.
* CLUSTER - only allow [HELP, SLOTS, NODES, INFO, MYID, LINKS, KEYSLOT, COUNTKEYSINSLOT,
  GETKEYSINSLOT, RESET, REPLICAS, COUNT_FAILURE_REPORTS], for others, preserve the status quo

## other fixes
* processEventsWhileBlocked had an issue when being nested, this could happen with a busy script
  during async loading (new), but also in a busy script during AOF loading (old). this lead to a crash in
  the scenario described in #6988
2021-12-22 14:11:16 +02:00
Meir Shpilraien (Spielrein)
3bcf108416
Change FUNCTION CREATE, DELETE and FLUSH to be WRITE commands instead of MAY_REPLICATE. (#9953)
The issue with MAY_REPLICATE is that all automatic mechanisms to handle
write commands will not work. This require have a special treatment for:
* Not allow those commands to be executed on RO replica.
* Allow those commands to be executed on RO replica from primary connection.
* Allow those commands to be executed on the RO replica from AOF.

By setting those commands as WRITE commands we are getting all those properties from Redis.
Test was added to verify that those properties work as expected.

In addition, rearrange when and where functions are flushed. Before this PR functions were
flushed manually on `rdbLoadRio` and cleaned manually on failure. This contradicts the
assumptions that functions are data and need to be created/deleted alongside with the
data. A side effect of this, for example, `debug reload noflush` did not flush the data but
did flush the functions, `debug loadaof` flush the data but not the functions.
This PR move functions deletion into `emptyDb`. `emptyDb` (renamed to `emptyData`) will
now accept an additional flag, `NOFUNCTIONS` which specifically indicate that we do not
want to flush the functions (on all other cases, functions will be flushed). Used the new flag
on FLUSHALL and FLUSHDB only! Tests were added to `debug reload` and `debug loadaof`
to verify that functions behave the same as the data.

Notice that because now functions will be deleted along side with the data we can not allow
`CLUSTER RESET` to be called from within a function (it will cause the function to be released
while running), this PR adds `NO_SCRIPT` flag to `CLUSTER RESET`  so it will not be possible
to be called from within a function. The other cluster commands are allowed from within a
function (there are use-cases that uses `GETKEYSINSLOT` to iterate over all the keys on a
given slot). Tests was added to verify `CLUSTER RESET` is denied from within a script.

Another small change on this PR is that `RDBFLAGS_ALLOW_DUP` is also applicable on functions.
When loading functions, if this flag is set, we will replace old functions with new ones on collisions.
2021-12-21 16:13:29 +02:00
zhugezy
1b0968df46
Remove EVAL script verbatim replication, propagation, and deterministic execution logic (#9812)
# 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: Oran Agra <oran@redislabs.com>
2021-12-21 08:32:42 +02:00
YaacovHazan
ae2f5b7b2e
Protected configs and sensitive commands (#9920)
Block sensitive configs and commands by default.

* `enable-protected-configs` - block modification of configs with the new `PROTECTED_CONFIG` flag.
   Currently we add this flag to `dbfilename`, and `dir` configs,
   all of which are non-mutable configs that can set a file redis will write to.
* `enable-debug-command` - block the `DEBUG` command
* `enable-module-command` - block the `MODULE` command

These have a default value set to `no`, so that these features are not
exposed by default to client connections, and can only be set by modifying the config file.

Users can change each of these to either `yes` (allow all access), or `local` (allow access from
local TCP connections and unix domain connections)

Note that this is a **breaking change** (specifically the part about MODULE command being disabled by default).
I.e. we don't consider DEBUG command being blocked as an issue (people shouldn't have been using it),
and the few configs we protected are unlikely to have been set at runtime anyway.
On the other hand, it's likely to assume some users who use modules, load them from the config file anyway.
Note that's the whole point of this PR, for redis to be more secure by default and reduce the attack surface on
innocent users, so secure defaults will necessarily mean a breaking change.
2021-12-19 10:46:16 +02:00
ny0312
792afb4432
Introduce memory management on cluster link buffers (#9774)
Introduce memory management on cluster link buffers:
 * Introduce a new `cluster-link-sendbuf-limit` config that caps memory usage of cluster bus link send buffers.
 * Introduce a new `CLUSTER LINKS` command that displays current TCP links to/from peers.
 * Introduce a new `mem_cluster_links` field under `INFO` command output, which displays the overall memory usage by all current cluster links.
 * Introduce a new `total_cluster_links_buffer_limit_exceeded` field under `CLUSTER INFO` command output, which displays the accumulated count of cluster links freed due to `cluster-link-sendbuf-limit`.
2021-12-16 21:56:59 -08:00
Meir Shpilraien (Spielrein)
687210f155
Add FUNCTION FLUSH command to flush all functions (#9936)
Added `FUNCTION FLUSH` command. The new sub-command allows delete all the functions.
An optional `[SYNC|ASYNC]` argument can be given to control whether or not to flush the
functions synchronously or asynchronously. if not given the default flush mode is chosen by
`lazyfree-lazy-user-flush` configuration values.

Add the missing `functions.tcl` test to the list of tests that are executed in test_helper.tcl,
and call FUNCTION FLUSH in between servers in external mode
2021-12-16 17:58:25 +02:00
guybe7
ffbe36fc3e
Command table: Sorted subcommands (#9951)
Sort the sub-commands so that every time we execute the script it generates the exact same results.
This will case less merge conflicts if two PRs edit different json files.

also:
* make the script agnostic to where it is executed (more flexible).
* add documentation about commands.c and the json files in the readme.

Co-authored-by: Oran Agra <oran@redislabs.com>
2021-12-16 12:54:40 +02:00
yoav-steinberg
70ff26b454
Multiparam config get. (#9914)
Support doing `CONFIG GET <x> <y> <z>`, each of them can also be
a pattern with wildcards.

This avoids duplicates in the result by looping over the configs and for
each once checking all the patterns, once a match is found for a pattern
we move on to the next config.
2021-12-16 09:01:13 +02:00
guybe7
867816003e
Auto-generate the command table from JSON files (#9656)
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: Itamar Haber <itamar@garantiadata.com>
2021-12-15 21:23:15 +02:00