Now that the command argument specs are available at runtime (#9656), this PR addresses
#8084 by implementing a complete solution for command-line hinting in `redis-cli`.
It correctly handles nearly every case in Redis's complex command argument definitions, including
`BLOCK` and `ONEOF` arguments, reordering of optional arguments, and repeated arguments
(even when followed by mandatory arguments). It also validates numerically-typed arguments.
It may not correctly handle all possible combinations of those, but overall it is quite robust.
Arguments are only matched after the space bar is typed, so partial word matching is not
supported - that proved to be more confusing than helpful. When the user's current input
cannot be matched against the argument specs, hinting is disabled.
Partial support has been implemented for legacy (pre-7.0) servers that do not support
`COMMAND DOCS`, by falling back to a statically-compiled command argument table.
On startup, if the server does not support `COMMAND DOCS`, `redis-cli` will now issue
an `INFO SERVER` command to retrieve the server version (unless `HELLO` has already
been sent, in which case the server version will be extracted from the reply to `HELLO`).
The server version will be used to filter the commands and arguments in the command table,
removing those not supported by that version of the server. However, the static table only
includes core Redis commands, so with a legacy server hinting will not be supported for
module commands. The auto generated help.h and the scripts that generates it are gone.
Command and argument tables for the server and CLI use different structs, due primarily
to the need to support different runtime data. In order to generate code for both, macros
have been added to `commands.def` (previously `commands.c`) to make it possible to
configure the code generation differently for different use cases (one linked with redis-server,
and one with redis-cli).
Also adding a basic testing framework for the command hints based on new (undocumented)
command line options to `redis-cli`: `--test_hint 'INPUT'` prints out the command-line hint for
a given input string, and `--test_hint_file <filename>` runs a suite of test cases for the hinting
mechanism. The test suite is in `tests/assets/test_cli_hint_suite.txt`, and it is run from
`tests/integration/redis-cli.tcl`.
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: Viktor Söderqvist <viktor.soderqvist@est.tech>
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.
This PR allows clients to send information about the client library to redis
to be displayed in CLIENT LIST and CLIENT INFO.
Currently supports:
`CLIENT [lib-name | lib-ver] <value>`
Client libraries are expected to pipeline these right after AUTH, and ignore
the failure in case they're talking to an older version of redis.
These will be shown in CLIENT LIST and CLIENT INFO as:
* `lib-name` - meant to hold the client library name.
* `lib-ver` - meant to hold the client library version.
The values cannot contain spaces, newlines and any wild ASCII characters,
but all other normal chars are accepted, e.g `.`, `=` etc (same as CLIENT NAME).
The RESET command does NOT clear these, but they can be cleared to the
default by sending a command with a blank string.
Co-authored-by: Oran Agra <oran@redislabs.com>
Allow running blocking commands from within a module using `RM_Call`.
Today, when `RM_Call` is used, the fake client that is used to run command
is marked with `CLIENT_DENY_BLOCKING` flag. This flag tells the command
that it is not allowed to block the client and in case it needs to block, it must
fallback to some alternative (either return error or perform some default behavior).
For example, `BLPOP` fallback to simple `LPOP` if it is not allowed to block.
All the commands must respect the `CLIENT_DENY_BLOCKING` flag (including
module commands). When the command invocation finished, Redis asserts that
the client was not blocked.
This PR introduces the ability to call blocking command using `RM_Call` by
passing a callback that will be called when the client will get unblocked.
In order to do that, the user must explicitly say that he allow to perform blocking
command by passing a new format specifier argument, `K`, to the `RM_Call`
function. This new flag will tell Redis that it is allow to run blocking command
and block the client. In case the command got blocked, Redis will return a new
type of call reply (`REDISMODULE_REPLY_PROMISE`). This call reply indicates
that the command got blocked and the user can set the on_unblocked handler using
`RM_CallReplyPromiseSetUnblockHandler`.
When clients gets unblocked, it eventually reaches `processUnblockedClients` function.
This is where we check if the client is a fake module client and if it is, we call the unblock
callback instead of performing the usual unblock operations.
**Notice**: `RM_CallReplyPromiseSetUnblockHandler` must be called atomically
along side the command invocation (without releasing the Redis lock in between).
In addition, unlike other CallReply types, the promise call reply must be released
by the module when the Redis GIL is acquired.
The module can abort the execution on the blocking command (if it was not yet
executed) using `RM_CallReplyPromiseAbort`. the API will return `REDISMODULE_OK`
on success and `REDISMODULE_ERR` if the operation is already executed.
**Notice** that in case of misbehave module, Abort might finished successfully but the
operation will not really be aborted. This can only happened if the module do not respect
the disconnect callback of the blocked client.
For pure Redis commands this can not happened.
### Atomicity Guarantees
The API promise that the unblock handler will run atomically as an execution unit.
This means that all the operation performed on the unblock handler will be wrapped
with a multi exec transaction when replicated to the replica and AOF.
The API **do not** grantee any other atomicity properties such as when the unblock
handler will be called. This gives us the flexibility to strengthen the grantees (or not)
in the future if we will decide that we need a better guarantees.
That said, the implementation **does** provide a better guarantees when performing
pure Redis blocking command like `BLPOP`. In this case the unblock handler will run
atomically with the operation that got unblocked (for example, in case of `BLPOP`, the
unblock handler will run atomically with the `LPOP` operation that run when the command
got unblocked). This is an implementation detail that might be change in the future and the
module writer should not count on that.
### Calling blocking commands while running on script mode (`S`)
`RM_Call` script mode (`S`) was introduced on #0372. It is used for usecases where the
command that was invoked on `RM_Call` comes from a user input and we want to make
sure the user will not run dangerous commands like `shutdown`. Some command, such
as `BLPOP`, are marked with `NO_SCRIPT` flag, which means they will not be allowed on
script mode. Those commands are marked with `NO_SCRIPT` just because they are
blocking commands and not because they are dangerous. Now that we can run blocking
commands on RM_Call, there is no real reason not to allow such commands on script mode.
The underline problem is that the `NO_SCRIPT` flag is abused to also mark some of the
blocking commands (notice that those commands know not to block the client if it is not
allowed to do so, and have a fallback logic to such cases. So even if those commands
were not marked with `NO_SCRIPT` flag, it would not harm Redis, and today we can
already run those commands within multi exec).
In addition, not all blocking commands are marked with `NO_SCRIPT` flag, for example
`blmpop` are not marked and can run from within a script.
Those facts shows that there are some ambiguity about the meaning of the `NO_SCRIPT`
flag, and its not fully clear where it should be use.
The PR suggest that blocking commands should not be marked with `NO_SCRIPT` flag,
those commands should handle `CLIENT_DENY_BLOCKING` flag and only block when
it's safe (like they already does today). To achieve that, the PR removes the `NO_SCRIPT`
flag from the following commands:
* `blmove`
* `blpop`
* `brpop`
* `brpoplpush`
* `bzpopmax`
* `bzpopmin`
* `wait`
This might be considered a breaking change as now, on scripts, instead of getting
`command is not allowed from script` error, the user will get some fallback behavior
base on the command implementation. That said, the change matches the behavior
of scripts and multi exec with respect to those commands and allow running them on
`RM_Call` even when script mode is used.
### Additional RedisModule API and changes
* `RM_BlockClientSetPrivateData` - Set private data on the blocked client without the
need to unblock the client. This allows up to set the promise CallReply as the private
data of the blocked client and abort it if the client gets disconnected.
* `RM_BlockClientGetPrivateData` - Return the current private data set on a blocked client.
We need it so we will have access to this private data on the disconnect callback.
* On RM_Call, the returned reply will be added to the auto memory context only if auto
memory is enabled, this allows us to keep the call reply for longer time then the context
lifetime and does not force an unneeded borrow relationship between the CallReply and
the RedisModuleContext.
Implementing the WAITAOF functionality which would allow the user to
block until a specified number of Redises have fsynced all previous write
commands to the AOF.
Syntax: `WAITAOF <num_local> <num_replicas> <timeout>`
Response: Array containing two elements: num_local, num_replicas
num_local is always either 0 or 1 representing the local AOF on the master.
num_replicas is the number of replicas that acknowledged the a replication
offset of the last write being fsynced to the AOF.
Returns an error when called on replicas, or when called with non-zero
num_local on a master with AOF disabled, in all other cases the response
just contains number of fsync copies.
Main changes:
* Added code to keep track of replication offsets that are confirmed to have
been fsynced to disk.
* Keep advancing master_repl_offset even when replication is disabled (and
there's no replication backlog, only if there's an AOF enabled).
This way we can use this command and it's mechanisms even when replication
is disabled.
* Extend REPLCONF ACK to `REPLCONF ACK <ofs> FACK <ofs>`, the FACK
will be appended only if there's an AOF on the replica, and already ignored on
old masters (thus backwards compatible)
* WAIT now no longer wait for the replication offset after your last command, but
rather the replication offset after your last write (or read command that caused
propagation, e.g. lazy expiry).
Unrelated changes:
* WAIT command respects CLIENT_DENY_BLOCKING (not just CLIENT_MULTI)
Implementation details:
* Add an atomic var named `fsynced_reploff_pending` that's updated
(usually by the bio thread) and later copied to the main `fsynced_reploff`
variable (only if the AOF base file exists).
I.e. during the initial AOF rewrite it will not be used as the fsynced offset
since the AOF base is still missing.
* Replace close+fsync bio job with new BIO_CLOSE_AOF (AOF specific)
job that will also update fsync offset the field.
* Handle all AOF jobs (BIO_CLOSE_AOF, BIO_AOF_FSYNC) in the same bio
worker thread, to impose ordering on their execution. This solves a
race condition where a job could set `fsynced_reploff_pending` to a higher
value than another pending fsync job, resulting in indicating an offset
for which parts of the data have not yet actually been fsynced.
Imposing an ordering on the jobs guarantees that fsync jobs are executed
in increasing order of replication offset.
* Drain bio jobs when switching `appendfsync` to "always"
This should prevent a write race between updates to `fsynced_reploff_pending`
in the main thread (`flushAppendOnlyFile` when set to ALWAYS fsync), and
those done in the bio thread.
* Drain the pending fsync when starting over a new AOF to avoid race conditions
with the previous AOF offsets overriding the new one (e.g. after switching to
replicate from a new master).
* Make sure to update the fsynced offset at the end of the initial AOF rewrite.
a must in case there are no additional writes that trigger a periodic fsync,
specifically for a replica that does a full sync.
Limitations:
It is possible to write a module and a Lua script that propagate to the AOF and doesn't
propagate to the replication stream. see REDISMODULE_ARGV_NO_REPLICAS and luaRedisSetReplCommand.
These features are incompatible with the WAITAOF command, and can result
in two bad cases. The scenario is that the user executes command that only
propagates to AOF, and then immediately
issues a WAITAOF, and there's no further writes on the replication stream after that.
1. if the the last thing that happened on the replication stream is a PING
(which increased the replication offset but won't trigger an fsync on the replica),
then the client would hang forever (will wait for an fack that the replica will never
send sine it doesn't trigger any fsyncs).
2. if the last thing that happened is a write command that got propagated properly,
then WAITAOF will be released immediately, without waiting for an fsync (since
the offset didn't change)
Refactoring:
* Plumbing to allow bio worker to handle multiple job types
This introduces infrastructure necessary to allow BIO workers to
not have a 1-1 mapping of worker to job-type. This allows in the
future to assign multiple job types to a single worker, either as
a performance/resource optimization, or as a way of enforcing
ordering between specific classes of jobs.
Co-authored-by: Oran Agra <oran@redislabs.com>
When no-touch mode is enabled, the client will not touch LRU/LFU of the
keys it accesses, except when executing command `TOUCH`.
This allows inspecting or modifying the key-space without affecting their eviction.
Changes:
- A command `CLIENT NO-TOUCH ON|OFF` to switch on and off this mode.
- A client flag `#define CLIENT_NOTOUCH (1ULL<<45)`, which can be shown
with `CLIENT INFO`, by the letter "T" in the "flags" field.
- Clear `NO-TOUCH` flag in `clearClientConnectionState`, which is used by `RESET`
command and resetting temp clients used by modules.
- Also clear `NO-EVICT` flag in `clearClientConnectionState`, this might have been an
oversight, spotted by @madolson.
- A test using `DEBUG OBJECT` command to verify that LRU stat is not touched when
no-touch mode is on.
Co-authored-by: chentianjie <chentianjie@alibaba-inc.com>
Co-authored-by: Madelyn Olson <34459052+madolson@users.noreply.github.com>
Co-authored-by: sundb <sundbcn@gmail.com>
Starting from Redis 7.0 (#9890) we started wrapping everything a command
propagates with MULTI/EXEC. The problem is that both SCAN and RANDOMKEY can
lazy-expire arbitrary keys (similar behavior to active-expire), and put DELs in a transaction.
Fix: When these commands are called without a parent exec-unit (e.g. not in EVAL or
MULTI) we avoid wrapping their DELs in a transaction (for the same reasons active-expire
and eviction avoids a transaction)
This PR adds a per-command flag that indicates that the command may touch arbitrary
keys (not the ones in the arguments), and uses that flag to avoid the MULTI-EXEC.
For now, this flag is internal, since we're considering other solutions for the future.
Note for cluster mode: if SCAN/RANDOMKEY is inside EVAL/MULTI it can still cause the
same situation (as it always did), but it won't cause a CROSSSLOT because replicas and AOF
do not perform slot checks.
The problem with the above is mainly for 3rd party ecosystem tools that propagate commands
from master to master, or feed an AOF file with redis-cli into a master.
This PR aims to fix the regression in redis 7.0, and we opened #11792 to try to handle the
bigger problem with lazy expire better for another release.
Added 3 fields to the ACL LOG - adds entry_id, timestamp_created and timestamp_last_updated, which updates similar existing log error entries. The pair - entry_id, timestamp_created is a unique identifier of this entry, in case the node dies and is restarted, it can detect that if it's a new series.
The primary use case of Unique id is to uniquely identify the error messages and not to detect if the server has restarted.
entry-id is the sequence number of the entry (starting at 0) since the server process started. Can also be used to check if items were "lost" if they fell between periods.
timestamp-created is the unix-time in ms at the time the entry was first created.
timestamp-last-updated is the unix-time in ms at the time the entry was last updated
Time_created gives the absolute time which better accounts for network time as compared to time since. It can also be older than 60 secs and presently there is no field that can display the original time of creation once the error entry is updated.
The reason of timestamp_last_updated field is that it provides a more precise value for the “last time” an error was seen where as, presently it is only in the 60 second period.
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
The command:
sentinel config set option value
and
sentinel config get option
They should include at least 4 arguments instead of 3,
This PR fixes this issue.
the only impact on the client is a different error message
Add an option "withscores" to ZRANK and ZREVRANK.
Add `[withscore]` option to both `zrank` and `zrevrank`, like this:
```
z[rev]rank key member [withscore]
```
Command SENTINEL DEBUG could be no arguments, which display all
configurable arguments and their values.
Update the command arguments in the docs (json file) to indicate that
arguments are optional
Technically, these commands were deprecated as of 2.6.12, with the
introduction of the respective arguments to SET.
In reality, the deprecation note will only be added in 7.2.0.
Introduce Shard IDs to logically group nodes in cluster mode.
1. Added a new "shard_id" field to "cluster nodes" output and nodes.conf after "hostname"
2. Added a new PING extension to propagate "shard_id"
3. Handled upgrade from pre-7.2 releases automatically
4. Refactored PING extension assembling/parsing logic
Behavior of Shard IDs:
Replicas will always follow the shards of their reported primaries. If a primary updates its shard ID, the replica will follow. (This need not follow for cluster v2) This is not an expected use case.
Clients should not use this command.
Instead, clients should simply close the connection when they're not used anymore.
Terminating a connection on the client side is preferable, as it eliminates `TIME_WAIT`
lingering sockets on the server side.
According to the source code, the commands can be executed with only key name,
and no GET/SET/INCR operation arguments.
change the docs to reflect that by marking these arguments as optional.
also add tests.
These commands take a list of members, which can be empty (i.e. running
the command with just a key name).
this always results in an empty array reply, so it doesn't make much sense,
but changing it is a breaking change.
This PR fixes the documentation, making the member field as optional, just makes
sure the command format documentation is consistent with the command behavior.
The command format will be:
127.0.0.1:6381> GEOPOS key [member [member ...]]
127.0.0.1:6381> GEOHASH key [member [member ...]]
The following two cases will create an empty destkey HLL:
1. called with no source keys, like `pfmerge destkey`
2. called with non-existing source keys, like `pfmerge destkey non-existing-source-key`
In the first case, in `PFMERGE`, the dest key is actually one of the source keys too.
So `PFMERGE k1 k2` is equivalent to `SUNIONSTORE k1 k1 k2`,
and `PFMERGE k1` is equivalent to `SUNIONSTORE k1 k1`.
So the first case is reasonable, the source key is actually optional.
And the second case, `PFMERGE` on missing keys should succeed and create an empty dest.
This is consistent with `PFCOUNT`, and also with `SUNIONSTORE`, no need to change.
- fix `the the` typo
- `LPOPRPUSH` does not exist, should be `RPOPLPUSH`
- `CLUSTER GETKEYINSLOT` 's time complexity should be O(N)
- `there bytes` should be `three bytes`, this closes#11266
- `slave` word to `replica` in log, modified the front and missed the back
- remove useless aofReadDiffFromParent in server.h
- `trackingHandlePendingKeyInvalidations` method adds a void parameter
- BITOP: turn argument `operation` from string to oneof
- CLIENT KILL: turn argument `skipme` from string to oneof
- COMMAND GETKEYS / GETKEYSANDFLAGS: change arguments to optional, and change arity to -3 (fixes regression in redis 7.0)
- CLIENT PAUSE: this command was added in v3.0.0
For the stream data type, some commands, such as **XGROUP CREATE, XGROUP DESTROY, XGROUP CREATECONSUMER,
XGROUP DELCONSUMER and XINFO CONSUMERS** use groupname and consumername in the command description;
However, for the commands **XREADGROUP GROUP, XPENDING, XACK , XCLAIM and XAUTOCLAIM** use term "group and consumer", clients could be confused.
This PR goal is to unify all the commands to groupname and consumername.
TLDR: the CLUSTER command originally had the `random` flag,
so all the sub-commands initially got that new flag, but in fact many
of them don't need it.
The only effect of this change is on the output of COMMAND INFO.
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).
The docs state that there is a new and an old argument format.
The current state of the arguments allows mixing the old and new format,
thus the need for two additional oneof blocks.
One for differentiating the new from the old format and then one to
allow setting multiple filters using the new format.
According to the Redis functions documentation, FCALL command format could be
FCALL function_name numberOfKeys [key1, key2, key3.....] [arg1, arg2, arg3.....]
So in the json file of fcall and fcall_ro, we should add optional for key and arg part.
Just like EVAL...
Co-authored-by: Binbin <binloveplay1314@qq.com>
This was harmless because we marked the parent command
with SENTINEL flag. So the populateCommandTable was ok.
And we also don't show the flag (SENTINEL and ONLY-SENTNEL)
in COMMAND INFO.
In this PR, we also add the same CMD_SENTINEL and CMD_ONLY_SENTINEL
flags check when populating the sub-commands.
so that in the future it'll be possible to add some sub-commands to sentinel or sentinel-only but not others.
Fix regression of CLUSTER RESET command in redis 7.0.
cluster reset command format is:
CLUSTER RESET [ HARD | SOFT]
According to the cluster reset command doc and codes, the third argument is optional, so
the arity in json file should be -2 instead of 3.
Add test to verify future regressions with RESET and RESET SOFT that were not covered.
Co-authored-by: Ubuntu <lucas.guang.yang1@huawei.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: Binbin <binloveplay1314@qq.com>
In 6.2.0 with the introduction of the REV subcommand in ZRANGE, there was a semantic shift in the arguments of ZRANGE when the REV sub-command is executed. Without the sub-command `min` and `max` (the old names of the arguments) are appropriate because if you put the min value and the max value in everything works fine.
```bash
127.0.0.1:6379> ZADD myset 0 foo
(integer) 1
127.0.0.1:6379> ZADD myset 1 bar
(integer) 1
127.0.0.1:6379> ZRANGE myset 0 inf BYSCORE
1) "foo"
2) "bar"
```
However - if you add the `REV` subcommand, ordering the arguments `min` `max` breaks the command:
```bash
127.0.0.1:6379> ZRANGE myset 0 inf BYSCORE REV
(empty array)
```
why? because `ZRANGE` with the `REV` sub-command is expecting the `max` first and the `min` second (because it's a reverse range like `ZREVRANGEBYSCORE`):
```bash
127.0.0.1:6379> ZRANGE myset 0 inf BYSCORE REV
(empty array)
```
In `CLUSTER MEET`, bus-port argument was added in 11436b1.
For cluster announce ip / port implementation, part of the
4.0-RC1.
And in #9389, we add a new cluster-port config and make
cluster bus port configurable, part of the 7.0-RC1.
I noticed that scripting.tcl uses INFO from within a script and thought it's an
overkill and concluded it's nicer to use another CMD_STALE command,
decided to use ECHO, and then noticed it's not at all allowed in stale mode.
probably overlooked at #6843
Correcting the introduction version of the command `BITFIELD_RO`
Command added by commit: b3e4abf06e
Add history info of the `FULL` modifier in `XINFO STREAM`
Modifier was added by commit: 1e2aee3919
(Includes output from `./utils/generate-command-code.py`)
Currently generate-command.help.rb dose not handle the
multiple_token flag, handle this flag in this PR.
The format is the same as redis-cli rendering.
```diff
- bitfield_ro key GET encoding offset [encoding offset ...]
+ bitfield_ro key GET encoding offset [GET encoding offset ...]
```
Re run generate-command-code.py which was forget in #10820.
Also change the flag value from string to bool, like "true" to true
There are some commands that has the wrong key specs.
This PR adds a key-spec related check in generate-command-code.py.
Check if the index is valid, or if there is an unused index.
The check result will look like:
```
[root]# python utils/generate-command-code.py
Processing json files...
Linking container command to subcommands...
Checking all commands...
command: RESTORE_ASKING may have unused key_spec
command: RENAME may have unused key_spec
command: PFDEBUG may have unused key_spec
command: WATCH key_specs missing flags
command: LCS arg: key2 key_spec_index error
command: RENAMENX may have unused key_spec
Error: There are errors in the commands check, please check the above logs.
```
The following commands have been fixed according to the check results:
- RESTORE ASKING: add missing arguments section (and history section)
- RENAME: newkey's key_spec_index should be 1
- PFDEBUG: add missing arguments (and change the arity from -3 to 3)
- WATCH: add missing key_specs flags: RO, like EXIST (it allow you to know the key exists, or is modified, but doesn't "leak" the data)
- LCS: key2 key_spec_index error, there is only one key-spec
- RENAMENX: newkey's key_spec_index should be 1
This PR fix the following minor errors before Redis 7 release:
ZRANGEBYLEX command in deprecated in 6.2.0, and could be replaced by ZRANGE with the
BYLEX argument, but in the document, the words is written incorrect in " by ZRANGE with the BYSCORE argument"
Fix function zpopmaxCommand incorrect comment
The comments of function zmpopCommand and bzmpopCommand are not consistent with document description, fix them
Co-authored-by: Ubuntu <lucas.guang.yang1@huawei.com>
Fixes in command argument in json files
* Fixes BITFIELD's syntax ("sub-commands" can be repeated, and OVERFLOW is only valid for SET and INCR)
* Improves readability of SET (reordered)
* Fixes GEOSEARCH and GEOSEARCH_RO syntices (use `oneof` for mutually exclusive group instead of `optional`)
* Fixes MIGRATE syntax (use `oneof` for mutually exclusive group instead of `optional`)
* Fixes MODULE LOADEX syntax (the `CONFIG` token should be repeated too when using multiple configs)
other:
* make generate-command-help.rb accept a path to commands.json, or read it from stdin (e.g. `generate-commands-json.py | generate-command-help.rb -`)
The command json documents should just include information about the "arguments" and the "outputs".
I removed all of the 'functional wording' so it's clear.
