RM_Call is designed to let modules call redis commands disregarding the
OOM state (the module is responsible to declare its command flags to redis,
or perform the necessary checks).
The other (new) alternative is to pass the "M" flag to RM_Call so that redis can
OOM reject commands implicitly.
However, Currently, RM_Call enforces OOM on scripts (excluding scripts that
declared `allow-oom`) in all cases, regardless of the RM_Call "M" flag being present.
This PR fixes scripts to be consistent with other commands being executed by RM_Call.
It modifies the flow in effect treats scripts as if they if they have the ALLOW_OOM script
flag, if the "M" flag is not passed (i.e. no OOM checking is being performed by RM_Call,
so no OOM checking should be done on script).
Co-authored-by: Oran Agra <oran@redislabs.com>
In the module, we will reuse the list iterator entry for RM_ListDelete, but `listTypeDelete` will only update
`quicklistEntry->zi` but not `quicklistEntry->node`, which will result in `quicklistEntry->node` pointing to
a freed memory address if the quicklist node is deleted.
This PR sync `key->u.list.index` and `key->u.list.entry` to list iterator after `RM_ListDelete`.
This PR also optimizes the release code of the original list iterator.
Co-authored-by: Viktor Söderqvist <viktor@zuiderkwast.se>
The use case is a module that wants to implement a blocking command on a key that
necessarily exists and wants to unblock the client in case the key is deleted (much like
what we implemented for XREADGROUP in #10306)
New module API:
* RedisModule_BlockClientOnKeysWithFlags
Flags:
* REDISMODULE_BLOCK_UNBLOCK_NONE
* REDISMODULE_BLOCK_UNBLOCK_DELETED
### Detailed description of code changes
blocked.c:
1. Both module and stream functions are called whether the key exists or not, regardless of
its type. We do that in order to allow modules/stream to unblock the client in case the key
is no longer present or has changed type (the behavior for streams didn't change, just code
that moved into serveClientsBlockedOnStreamKey)
2. Make sure afterCommand is called in serveClientsBlockedOnKeyByModule, in order to propagate
actions from moduleTryServeClientBlockedOnKey.
3. handleClientsBlockedOnKeys: call propagatePendingCommands directly after lookupKeyReadWithFlags
to prevent a possible lazy-expire DEL from being mixed with any command propagated by the
preceding functions.
4. blockForKeys: Caller can specifiy that it wants to be awakened if key is deleted.
Minor optimizations (use dictAddRaw).
5. signalKeyAsReady became signalKeyAsReadyLogic which can take a boolean in case the key is deleted.
It will only signal if there's at least one client that awaits key deletion (to save calls to
handleClientsBlockedOnKeys).
Minor optimizations (use dictAddRaw)
db.c:
1. scanDatabaseForDeletedStreams is now scanDatabaseForDeletedKeys and will signalKeyAsReady
for any key that was removed from the database or changed type. It is the responsibility of the code
in blocked.c to ignore or act on deleted/type-changed keys.
2. Use the new signalDeletedKeyAsReady where needed
blockedonkey.c + tcl:
1. Added test of new capabilities (FSL.BPOPGT now requires the key to exist in order to work)
### Background
The issue is that when saving an RDB with module AUX data, the module AUX metadata
(moduleid, when, ...) is saved to the RDB even though the module did not saved any actual data.
This prevent loading the RDB in the absence of the module (although there is no actual data in
the RDB that requires the module to be loaded).
### Solution
The solution suggested in this PR is that module AUX will be saved on the RDB only if the module
actually saved something during `aux_save` function.
To support backward compatibility, we introduce `aux_save2` callback that acts the same as
`aux_save` with the tiny change of avoid saving the aux field if no data was actually saved by
the module. Modules can use the new API to make sure that if they have no data to save,
then it will be possible to load the created RDB even without the module.
### Concerns
A module may register for the aux load and save hooks just in order to be notified when
saving or loading starts or completed (there are better ways to do that, but it still possible
that someone used it).
However, if a module didn't save a single field in the save callback, it means it's not allowed
to read in the read callback, since it has no way to distinguish between empty and non-empty
payloads. furthermore, it means that if the module did that, it must never change it, since it'll
break compatibility with it's old RDB files, so this is really not a valid use case.
Since some modules (ones who currently save one field indicating an empty payload), need
to know if saving an empty payload is valid, and if Redis is gonna ignore an empty payload
or store it, we opted to add a new API (rather than change behavior of an existing API and
expect modules to check the redis version)
### Technical Details
To avoid saving AUX data on RDB, we change the code to first save the AUX metadata
(moduleid, when, ...) into a temporary buffer. The buffer is then flushed to the rio at the first
time the module makes a write operation inside the `aux_save` function. If the module saves
nothing (and `aux_save2` was used), the entire temporary buffer is simply dropped and no
data about this AUX field is saved to the RDB. This make it possible to load the RDB even in
the absence of the module.
Test was added to verify the fix.
Motivation: for applications that use RM ACL verification functions, they would
want to return errors back to the user, in ways that are consistent with Redis.
While investigating how we should return ACL errors to the user, we realized that
Redis isn't consistent, and currently returns ACL error strings in 3 primary ways.
[For the actual implications of this change, see the "Impact" section at the bottom]
1. how it returns an error when calling a command normally
ACL_DENIED_CMD -> "this user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "this user has no permissions to access one of the keys used as arguments"
ACL_DENIED_CHANNEL -> "this user has no permissions to access one of the channels used as arguments"
2. how it returns an error when calling via 'acl dryrun' command
ACL_DENIED_CMD -> "This user has no permissions to run the '%s' command"
ACL_DENIED_KEY -> "This user has no permissions to access the '%s' key"
ACL_DENIED_CHANNEL -> "This user has no permissions to access the '%s' channel"
3. how it returns an error via RM_Call (and scripting is similar).
ACL_DENIED_CMD -> "can't run this command or subcommand";
ACL_DENIED_KEY -> "can't access at least one of the keys mentioned in the command arguments";
ACL_DENIED_CHANNEL -> "can't publish to the channel mentioned in the command";
In addition, if one wants to use RM_Call's "dry run" capability instead of the RM ACL
functions directly, one also sees a different problem than it returns ACL errors with a -ERR,
not a -PERM, so it can't be returned directly to the caller.
This PR modifies the code to generate a base message in a common manner with the ability
to set verbose flag for acl dry run errors, and keep it unset for normal/rm_call/script cases
```c
sds getAclErrorMessage(int acl_res, user *user, struct redisCommand *cmd, sds errored_val, int verbose) {
switch (acl_res) {
case ACL_DENIED_CMD:
return sdscatfmt(sdsempty(), "User %S has no permissions to run "
"the '%S' command", user->name, cmd->fullname);
case ACL_DENIED_KEY:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' key", user->name, errored_val);
} else {
return sdsnew("No permissions to access a key");
}
case ACL_DENIED_CHANNEL:
if (verbose) {
return sdscatfmt(sdsempty(), "User %S has no permissions to access "
"the '%S' channel", user->name, errored_val);
} else {
return sdsnew("No permissions to access a channel");
}
}
```
The caller can append/prepend the message (adding NOPERM for normal/RM_Call or indicating it's within a script).
Impact:
- Plain commands, as well as scripts and RM_Call now include the user name.
- ACL DRYRUN remains the only one that's verbose (mentions the offending channel or key name)
- Changes RM_Call ACL errors from being a `-ERR` to being `-NOPERM` (besides for textual changes)
**This somewhat a breaking change, but it only affects the RM_Call with both `C` and `E`, or `D`**
- Changes ACL errors in scripts textually from being
`The user executing the script <old non unified text>`
to
`ACL failure in script: <new unified text>`
As discussed on #11084, `propagatePendingCommands` should happened after the del
notification is fired so that the notification effect and the `del` will be replicated inside MULTI EXEC.
Test was added to verify the fix.
PR #9320 introduces initialization order changes. Now cluster is initialized after modules.
This changes causes a crash if the module uses RM_Call inside the load function
on cluster mode (the code will try to access `server.cluster` which at this point is NULL).
To solve it, separate cluster initialization into 2 phases:
1. Structure initialization that happened before the modules initialization
2. Listener initialization that happened after.
Test was added to verify the fix.
As mentioned on docs, `RM_ResetDataset` Performs similar operation to FLUSHALL.
As FLUSHALL do not clean the function, `RM_ResetDataset` should not clean the functions
as well.
The original idea behind auto-setting the default (first,last,step) spec was to use
the most "open" flags when the user didn't provide any key-spec flags information.
While the above idea is a good approach, it really makes no sense to set
CMD_KEY_VARIABLE_FLAGS if the user didn't provide the getkeys-api flag:
in this case there's not way to retrieve these variable flags, so what's the point?
Internally in redis there was code to ignore this already, so this fix doesn't change
redis's behavior, it only affects the output of COMMAND command.
If a command gets an OOM response and then if we set maxmemory to zero
to disable the limit, server.pre_command_oom_state never gets updated
and it stays true. As RM_Call() calls with "respect deny-oom" flag checks
server.pre_command_oom_state, all calls will fail with OOM.
Added server.maxmemory check in RM_Call() to process deny-oom flag
only if maxmemory is configured.
Adds a number of user management/ACL validaiton/command execution functions to improve a
Redis module's ability to enforce ACLs correctly and easily.
* RM_SetContextUser - sets a RedisModuleUser on the context, which RM_Call will use to both
validate ACLs (if requested and set) as well as assign to the client so that scripts executed via
RM_Call will have proper ACL validation.
* RM_SetModuleUserACLString - Enables one to pass an entire ACL string, not just a single OP
and have it applied to the user
* RM_GetModuleUserACLString - returns a stringified version of the user's ACL (same format as dump
and list). Contains an optimization to cache the stringified version until the underlying ACL is modified.
* Slightly re-purpose the "C" flag to RM_Call from just being about ACL check before calling the
command, to actually running the command with the right user, so that it also affects commands
inside EVAL scripts. see #11231
When using `INFO ALL <section>`, when `section` is a specific module section.
Redis will not print the additional section(s).
The fix in this case, will search the modules info sections if the user provided additional sections to `ALL`.
Co-authored-by: Oran Agra <oran@redislabs.com>
Add a new "D" flag to RM_Call which runs whatever verification the user requests,
but returns before the actual execution of the command.
It automatically enables returning error messages as CallReply objects to distinguish
success (NULL) from failure (CallReply returned).
When RM_Call was used with `M` (reject OOM), `W` (reject writes),
as well as `S` (rejecting stale or write commands in "Script mode"),
it would have only checked the command flags, but not the declared
script flag in case it's a command that runs a script.
Refactoring: extracts out similar code in server.c's processCommand
to be usable in RM_Call as well.
The PR reverts the changes made on #10969.
The reason for revert was trigger because of occasional test failure
that started after the PR was merged.
The issue is that if there is a lazy expire during the command invocation,
the `del` command is added to the replication stream after the command
placeholder. So the logical order on the primary is:
* Delete the key (lazy expiration)
* Command invocation
But the replication stream gets it the other way around:
* Command invocation (because the command is written into the placeholder)
* Delete the key (lazy expiration)
So if the command write to the key that was just lazy expired we will get
inconsistency between primary and replica.
One solution we considered is to add another lazy expire replication stream
and write all the lazy expire there. Then when replicating, we will replicate the
lazy expire replication stream first. This will solve this specific test failure but
we realize that the issues does not ends here and the more we dig the more
problems we find.One of the example we thought about (that can actually
crashes Redis) is as follow:
* User perform SINTERSTORE
* When Redis tries to fetch the second input key it triggers lazy expire
* The lazy expire trigger a module logic that deletes the first input key
* Now Redis hold the robj of the first input key that was actually freed
We believe we took the wrong approach and we will come up with another
PR that solve the problem differently, for now we revert the changes so we
will not have the tests failure.
Notice that not the entire code was revert, some parts of the PR are changes
that we would like to keep. The changes that **was** reverted are:
* Saving a placeholder for replication at the beginning of the command (`call` function)
* Order of the replication stream on active expire and eviction (we will decide how
to handle it correctly on follow up PR)
* `Spop` changes are no longer needed (because we reverted the placeholder code)
Changes that **was not** reverted:
* On expire/eviction, wrap the `del` and the notification effect in a multi exec.
* `PropagateNow` function can still accept a special dbid, -1, indicating not to replicate select.
* Keep optimisation for reusing the `alsoPropagate` array instead of allocating it each time.
Tests:
* All tests was kept and only few tests was modify to work correctly with the changes
* Test was added to verify that the revert fixes the issues.
* Support BUILD_TLS=module to be loaded as a module via config file or
command line. e.g. redis-server --loadmodule redis-tls.so
* Updates to redismodule.h to allow it to be used side by side with
server.h by defining REDISMODULE_CORE_MODULE
* Changes to server.h, redismodule.h and module.c to avoid repeated
type declarations (gcc 4.8 doesn't like these)
* Add a mechanism for non-ABI neutral modules (ones who include
server.h) to refuse loading if they detect not being built together with
redis (release.c)
* Fix wrong signature of RedisModuleDefragFunc, this could break
compilation of a module, but not the ABI
* Move initialization of listeners in server.c to be after loading
the modules
* Config TLS after initialization of listeners
* Init cluster after initialization of listeners
* Add TLS module to CI
* Fix a test suite race conditions:
Now that the listeners are initialized later, it's not sufficient to
wait for the PID message in the log, we need to wait for the "Server
Initialized" message.
* Fix issues with moduleconfigs test as a result from start_server
waiting for "Server Initialized"
* Fix issues with modules/infra test as a result of an additional module
present
Notes about Sentinel:
Sentinel can't really rely on the tls module, since it uses hiredis to
initiate connections and depends on OpenSSL (won't be able to use any
other connection modules for that), so it was decided that when TLS is
built as a module, sentinel does not support TLS at all.
This means that it keeps using redis_tls_ctx and redis_tls_client_ctx directly.
Example code of config in redis-tls.so(may be use in the future):
RedisModuleString *tls_cfg = NULL;
void tlsInfo(RedisModuleInfoCtx *ctx, int for_crash_report) {
UNUSED(for_crash_report);
RedisModule_InfoAddSection(ctx, "");
RedisModule_InfoAddFieldLongLong(ctx, "var", 42);
}
int tlsCommand(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
{
if (argc != 2) return RedisModule_WrongArity(ctx);
return RedisModule_ReplyWithString(ctx, argv[1]);
}
RedisModuleString *getStringConfigCommand(const char *name, void *privdata) {
REDISMODULE_NOT_USED(name);
REDISMODULE_NOT_USED(privdata);
return tls_cfg;
}
int setStringConfigCommand(const char *name, RedisModuleString *new, void *privdata, RedisModuleString **err) {
REDISMODULE_NOT_USED(name);
REDISMODULE_NOT_USED(err);
REDISMODULE_NOT_USED(privdata);
if (tls_cfg) RedisModule_FreeString(NULL, tls_cfg);
RedisModule_RetainString(NULL, new);
tls_cfg = new;
return REDISMODULE_OK;
}
int RedisModule_OnLoad(void *ctx, RedisModuleString **argv, int argc)
{
....
if (RedisModule_CreateCommand(ctx,"tls",tlsCommand,"",0,0,0) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_RegisterStringConfig(ctx, "cfg", "", REDISMODULE_CONFIG_DEFAULT, getStringConfigCommand, setStringConfigCommand, NULL, NULL) == REDISMODULE_ERR)
return REDISMODULE_ERR;
if (RedisModule_LoadConfigs(ctx) == REDISMODULE_ERR) {
if (tls_cfg) {
RedisModule_FreeString(ctx, tls_cfg);
tls_cfg = NULL;
}
return REDISMODULE_ERR;
}
...
}
Co-authored-by: zhenwei pi <pizhenwei@bytedance.com>
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Currently, we call zfree(cmd->args), but the argument array
needs to be freed recursively (there might be sub-args).
Also fixed memory leaks on cmd->tips and cmd->history.
Fixes#11145
Fix replication inconsistency on modules that uses key space notifications.
### The Problem
In general, key space notifications are invoked after the command logic was
executed (this is not always the case, we will discuss later about specific
command that do not follow this rules). For example, the `set x 1` will trigger
a `set` notification that will be invoked after the `set` logic was performed, so
if the notification logic will try to fetch `x`, it will see the new data that was written.
Consider the scenario on which the notification logic performs some write
commands. for example, the notification logic increase some counter,
`incr x{counter}`, indicating how many times `x` was changed.
The logical order by which the logic was executed is has follow:
```
set x 1
incr x{counter}
```
The issue is that the `set x 1` command is added to the replication buffer
at the end of the command invocation (specifically after the key space
notification logic was invoked and performed the `incr` command).
The replication/aof sees the commands in the wrong order:
```
incr x{counter}
set x 1
```
In this specific example the order is less important.
But if, for example, the notification would have deleted `x` then we would
end up with primary-replica inconsistency.
### The Solution
Put the command that cause the notification in its rightful place. In the
above example, the `set x 1` command logic was executed before the
notification logic, so it should be added to the replication buffer before
the commands that is invoked by the notification logic. To achieve this,
without a major code refactoring, we save a placeholder in the replication
buffer, when finishing invoking the command logic we check if the command
need to be replicated, and if it does, we use the placeholder to add it to the
replication buffer instead of appending it to the end.
To be efficient and not allocating memory on each command to save the
placeholder, the replication buffer array was modified to reuse memory
(instead of allocating it each time we want to replicate commands).
Also, to avoid saving a placeholder when not needed, we do it only for
WRITE or MAY_REPLICATE commands.
#### Additional Fixes
* Expire and Eviction notifications:
* Expire/Eviction logical order was to first perform the Expire/Eviction
and then the notification logic. The replication buffer got this in the
other way around (first notification effect and then the `del` command).
The PR fixes this issue.
* The notification effect and the `del` command was not wrap with
`multi-exec` (if needed). The PR also fix this issue.
* SPOP command:
* On spop, the `spop` notification was fired before the command logic
was executed. The change in this PR would have cause the replication
order to be change (first `spop` command and then notification `logic`)
although the logical order is first the notification logic and then the
`spop` logic. The right fix would have been to move the notification to
be fired after the command was executed (like all the other commands),
but this can be considered a breaking change. To overcome this, the PR
keeps the current behavior and changes the `spop` code to keep the right
logical order when pushing commands to the replication buffer. Another PR
will follow to fix the SPOP properly and match it to the other command (we
split it to 2 separate PR's so it will be easy to cherry-pick this PR to 7.0 if
we chose to).
#### Unhanded Known Limitations
* key miss event:
* On key miss event, if a module performed some write command on the
event (using `RM_Call`), the `dirty` counter would increase and the read
command that cause the key miss event would be replicated to the replication
and aof. This problem can also happened on a write command that open
some keys but eventually decides not to perform any action. We decided
not to handle this problem on this PR because the solution is complex
and will cause additional risks in case we will want to cherry-pick this PR.
We should decide if we want to handle it in future PR's. For now, modules
writers is advice not to perform any write commands on key miss event.
#### Testing
* We already have tests to cover cases where a notification is invoking write
commands that are also added to the replication buffer, the tests was modified
to verify that the replica gets the command in the correct logical order.
* Test was added to verify that `spop` behavior was kept unchanged.
* Test was added to verify key miss event behave as expected.
* Test was added to verify the changes do not break lazy expiration.
#### Additional Changes
* `propagateNow` function can accept a special dbid, -1, indicating not
to replicate `select`. We use this to replicate `multi/exec` on `propagatePendingCommands`
function. The side effect of this change is that now the `select` command
will appear inside the `multi/exec` block on the replication stream (instead of
outside of the `multi/exec` block). Tests was modified to match this new behavior.
A timing issue like this was reported in freebsd daily CI:
```
*** [err]: Sanity test push cmd after resharding in tests/unit/cluster/cli.tcl
Expected 'CLUSTERDOWN The cluster is down' to match '*MOVED*'
```
We additionally wait for each node to reach a consensus on the cluster
state in wait_for_condition to avoid the cluster down error.
The fix just like #10495, quoting madolson's comment:
Cluster check just verifies the the config state is self-consistent,
waiting for cluster_state to be okay is an independent check that all
the nodes actually believe each other are healthy.
At the same time i noticed that unit/moduleapi/cluster.tcl has an exact
same test, may have the same problem, also modified it.
Since the ranges of `unsigned long long` and `long long` are different, we cannot read an
`unsigned long long` integer from a `RedisModuleString` by `RedisModule_StringToLongLong` .
So I added two new Redis Module APIs to support the conversion between these two types:
* `RedisModule_StringToULongLong`
* `RedisModule_CreateStringFromULongLong`
Signed-off-by: RinChanNOWWW <hzy427@gmail.com>
The PR fixes 2 issues:
### RM_Call crash on script mode
`RM_Call` can potentially be called from a background thread where `server.current_client`
are not set. In such case we get a crash on `NULL` dereference.
The fix is to check first if `server.current_client` is `NULL`, if it does we should
verify disc errors and readonly replica as we do to any normal clients (no masters nor AOF).
### RM_Call block OOM commands when not needed
Again `RM_Call` can be executed on a background thread using a `ThreadSafeCtx`.
In such case `server.pre_command_oom_state` can be irrelevant and should not be
considered when check OOM state. This cause OOM commands to be blocked when
not necessarily needed.
In such case, check the actual used memory (and not the cached value). Notice that in
order to know if the cached value can be used, we check that the ctx that was used on
the `RM_Call` is a ThreadSafeCtx. Module writer can potentially abuse the API and use
ThreadSafeCtx on the main thread. We consider this as a API miss used.
The SET and BITFIELD command were added `get_keys_function` in #10148, causing
them to be wrongly marked movablekeys in `populateCommandMovableKeys`.
This was an unintended side effect introduced in #10148 (7.0 RC1)
which could cause some clients an extra round trip for these commands in cluster mode.
Since we define movablekeys as a way to determine if the legacy range [first, last, step]
doesn't find all keys, then we need a completely different approach.
The right approach should be to check if the legacy range covers all key-specs,
and if none of the key-specs have the INCOMPLETE flag.
This way, we don't need to look at getkeys_proc of VARIABLE_FLAG at all.
Probably with the exception of modules, who may still not be using key-specs.
In this PR, we removed `populateCommandMovableKeys` and put its logic in
`populateCommandLegacyRangeSpec`.
In order to properly serve both old and new modules, we must probably keep relying
CMD_MODULE_GETKEYS, but do that only for modules that don't declare key-specs.
For ones that do, we need to take the same approach we take with native redis commands.
This approach was proposed by Oran. Fixes#10833
Co-authored-by: Oran Agra <oran@redislabs.com>
The important part is that read-only scripts (not just EVAL_RO
and FCALL_RO, but also ones with `no-writes` executed by normal EVAL or
FCALL), will now be permitted to run during CLIENT PAUSE WRITE (unlike
before where only the _RO commands would be processed).
Other than that, some errors like OOM, READONLY, MASTERDOWN are now
handled by processCommand, rather than the command itself affects the
error string (and even error code in some cases), and command stats.
Besides that, now the `may-replicate` commands, PFCOUNT and PUBLISH, will
be considered `write` commands in scripts and will be blocked in all
read-only scripts just like other write commands.
They'll also be blocked in EVAL_RO (i.e. even for scripts without the
`no-writes` shebang flag.
This commit also hides the `may_replicate` flag from the COMMAND command
output. this is a **breaking change**.
background about may_replicate:
We don't want to expose a no-may-replicate flag or alike to scripts, since we
consider the may-replicate thing an internal concern of redis, that we may
some day get rid of.
In fact, the may-replicate flag was initially introduced to flag EVAL: since
we didn't know what it's gonna do ahead of execution, before function-flags
existed). PUBLISH and PFCOUNT, both of which because they have side effects
which may some day be fixed differently.
code changes:
The changes in eval.c are mostly code re-ordering:
- evalCalcFunctionName is extracted out of evalGenericCommand
- evalExtractShebangFlags is extracted luaCreateFunction
- evalGetCommandFlags is new code
* Fix broken protocol when redis can't persist to RDB (general commands, not
modules), excessive newline. regression of #10372 (7.0 RC3)
* Fix broken protocol when Redis can't persist to AOF (modules and
scripts), missing newline.
* Fix bug in OOM check of EVAL scripts called from RM_Call.
set the cached OOM state for scripts before executing module commands too,
so that it can serve scripts that are executed by modules.
i.e. in the past EVAL executed by RM_Call could have either falsely
fail or falsely succeeded because of a wrong cached OOM state flag.
* Fix bugs with RM_Yield:
1. SHUTDOWN should only accept the NOSAVE mode
2. Avoid eviction during yield command processing.
3. Avoid processing master client commands while yielding from another client
* Add new two more checks to RM_Call script mode.
1. READONLY You can't write against a read only replica
2. MASTERDOWN Link with MASTER is down and `replica-serve-stale-data` is set to `no`
* Add new RM_Call flag to let redis automatically refuse `deny-oom` commands
while over the memory limit.
* Add tests to cover various errors from Scripts, Modules, Modules
calling scripts, and Modules calling commands in script mode.
Add tests:
* Looks like the MISCONF error was completely uncovered by the tests,
add tests for it, including from scripts, and modules
* Add tests for NOREPLICAS from scripts
* Add tests for the various errors in module RM_Call, including RM_Call that
calls EVAL, and RM_call in "eval mode". that includes:
NOREPLICAS, READONLY, MASTERDOWN, MISCONF
To easily distinguish between sharded channel message and a global
channel message, introducing `smessage` (instead of `message`) as
message bulk for sharded channel publish message.
This is gonna be a breaking change in 7.0.1!
Background:
Sharded pubsub introduced in redis 7.0, but after the release we quickly
realized that the fact that it's problematic that the client can't distinguish
between normal (global) pubsub messages and sharded ones.
This is important because the same connection can subscribe to both,
but messages sent to one pubsub system are not propagated to the
other (they're completely separate), so if one connection is used to
subscribe to both, we need to assist the client library to know which
message it got so it can forward it to the correct callback.
The purpose of the test is to kill the child while it is running.
From the last two lines we can see the child exits before being killed.
```
- Module fork started pid: 56998
* <fork> fork child started
- Killing running module fork child: 56998
* <fork> fork child exiting
signal-handler (1652267501) Received SIGUSR1 in child, exiting now.
```
In this commit, we pass an argument to `fork.create` indicating how
long it should sleep. For the fork kill test, we use a longer time to
avoid the child exiting before being killed.
Other changes:
use wait_for_condition instead of hardcoded `after 250`.
Unify the test for failing fork with the one for killing it (save time)
If we want to support bits that can be overlapping, we need to make sure
that:
1. we don't use the same bit for two return values.
2. values should be sorted so that prefer ones (matching more
bits) come first.
Enables registration of an enum config that'll let the user pass multiple keywords that
will be combined with `|` as flags into the integer config value.
```
const char *enum_vals[] = {"none", "one", "two", "three"};
const int int_vals[] = {0, 1, 2, 4};
if (RedisModule_RegisterEnumConfig(ctx, "flags", 3, REDISMODULE_CONFIG_DEFAULT | REDISMODULE_CONFIG_BITFLAGS, enum_vals, int_vals, 4, getFlagsConfigCommand, setFlagsConfigCommand, NULL, NULL) == REDISMODULE_ERR) {
return REDISMODULE_ERR;
}
```
doing:
`config set moduleconfigs.flags "two three"` will result in 6 being passed to`setFlagsConfigCommand`.
The SHUTDOWN command has various flags to change it's default behavior,
but in some cases establishing a connection to redis is complicated and it's easier
for the management software to use signals. however, so far the signals could only
trigger the default shutdown behavior.
Here we introduce the option to control shutdown arguments for SIGTERM and SIGINT.
New config options:
`shutdown-on-sigint [nosave | save] [now] [force]`
`shutdown-on-sigterm [nosave | save] [now] [force]`
Implementation:
Support MULTI_ARG_CONFIG on createEnumConfig to support multiple enums to be applied as bit flags.
Co-authored-by: Oran Agra <oran@redislabs.com>
Adds the `allow-cross-slot-keys` flag to Eval scripts and Functions to allow
scripts to access keys from multiple slots.
The default behavior is now that they are not allowed to do that (unlike before).
This is a breaking change for 7.0 release candidates (to be part of 7.0.0), but
not for previous redis releases since EVAL without shebang isn't doing this check.
Note that the check is done on both the keys declared by the EVAL / FCALL command
arguments, and also the ones used by the script when making a `redis.call`.
A note about the implementation, there seems to have been some confusion
about allowing access to non local keys. I thought I missed something in our
wider conversation, but Redis scripts do block access to non-local keys.
So the issue was just about cross slots being accessed.
1. Disk error and slave count checks didn't flag the transactions or counted correctly in command stats (regression from #10372 , 7.0 RC3)
2. RM_Call will reply the same way Redis does, in case of non-exisitng command or arity error
3. RM_WrongArtiy will consider the full command name
4. Use lowercase 'u' in "unknonw subcommand" (to align with "unknown command")
Followup work of #10127
This case is interesting because it originates from cron,
rather than from another command.
The idea came from looking at #9890 and #10573, and I was wondering if RM_Call
would work properly when `server.current_client == NULL`
RM_Yield was missing a call to protectClient to prevent redis from
processing future commands of the yielding client.
Adding tests that fail without this fix.
This would be complicated to solve since nested calls to RM_Call used to
replace the current_client variable with the module temp client.
It looks like it's no longer necessary to do that, since it was added
back in #9890 to solve two issues, both already gone:
1. call to CONFIG SET maxmemory could trigger a module hook calling
RM_Call. although this specific issue is gone, arguably other hooks
like keyspace notification, can do the same.
2. an assertion in lookupKey that checks the current command of the
current client, introduced in #9572 and removed in #10248
since PUBLISH and SPUBLISH use different dictionaries for channels and clients,
and we already have an API for PUBLISH, it only makes sense to have one for SPUBLISH
Add test coverage and unifying some test infrastructure.
Add APIs to allow modules to compute the memory consumption of opaque objects owned by redis.
Without these, the mem_usage callbacks of module data types are useless in many cases.
Other changes:
Fix streamRadixTreeMemoryUsage to include the size of the rax structure itself
By the convention of errors, there is supposed to be a space between the code and the name.
While looking at some lua stuff I noticed that interpreter errors were not adding the space,
so some clients will try to map the detailed error message into the error.
We have tests that hit this condition, but they were just checking that the string "starts" with ERR.
I updated some other tests with similar incorrect string checking. This isn't complete though, as
there are other ways we check for ERR I didn't fix.
Produces some fun output like:
```
# Errorstats
errorstat_ERR:count=1
errorstat_ERRuser_script_1_:count=1
```
Allow specifying an ACL log reason, which is shown in the log. Right now it always shows "unknown", which is a little bit cryptic. This is a breaking change, but this API was added as part of 7 so it seems ok to stabilize it still.
Add field to COMMAND DOCS response to denote the name of the module
that added that command.
COMMAND LIST can filter by module, but if you get the full commands list,
you may still wanna know which command belongs to which module.
The alternative would be to do MODULE LIST, and then multiple calls to COMMAND LIST
The bug was when using REDISMODULE_YIELD_FLAG_CLIENTS.
in that case we would have only set the CLIENTS type flag in
server.busy_module_yield_flags and then clear that flag when exiting
RM_Yield, so we would never call unblockPostponedClients when the
context is destroyed.
This didn't really have any actual implication, which is why the tests
couldn't (and still can't) find that since the bug only happens when
using CLIENT, but in this case we won't have any clients to un-postpone
i.e. clients will get rejected with BUSY error, rather than being
postponed.
Unrelated:
* Adding tests for nested contexts, just in case.
* Avoid nested RM_Yield calls
Fix global `strval` not reset to NULL after being freed, causing a crash on alpine
(most likely because the dynamic library loader doesn't init globals on reload)
By the way, fix the memory leak of using `RedisModule_Free` to free `RedisModuleString`,
and add a corresponding test.
This feature adds the ability to add four different types (Bool, Numeric,
String, Enum) of configurations to a module to be accessed via the redis
config file, and the CONFIG command.
**Configuration Names**:
We impose a restriction that a module configuration always starts with the
module name and contains a '.' followed by the config name. If a module passes
"config1" as the name to a register function, it will be registered as MODULENAME.config1.
**Configuration Persistence**:
Module Configurations exist only as long as a module is loaded. If a module is
unloaded, the configurations are removed.
There is now also a minimal core API for removal of standardConfig objects
from configs by name.
**Get and Set Callbacks**:
Storage of config values is owned by the module that registers them, and provides
callbacks for Redis to access and manipulate the values.
This is exposed through a GET and SET callback.
The get callback returns a typed value of the config to redis. The callback takes
the name of the configuration, and also a privdata pointer. Note that these only
take the CONFIGNAME portion of the config, not the entire MODULENAME.CONFIGNAME.
```
typedef RedisModuleString * (*RedisModuleConfigGetStringFunc)(const char *name, void *privdata);
typedef long long (*RedisModuleConfigGetNumericFunc)(const char *name, void *privdata);
typedef int (*RedisModuleConfigGetBoolFunc)(const char *name, void *privdata);
typedef int (*RedisModuleConfigGetEnumFunc)(const char *name, void *privdata);
```
Configs must also must specify a set callback, i.e. what to do on a CONFIG SET XYZ 123
or when loading configurations from cli/.conf file matching these typedefs. *name* is
again just the CONFIGNAME portion, *val* is the parsed value from the core,
*privdata* is the registration time privdata pointer, and *err* is for providing errors to a client.
```
typedef int (*RedisModuleConfigSetStringFunc)(const char *name, RedisModuleString *val, void *privdata, RedisModuleString **err);
typedef int (*RedisModuleConfigSetNumericFunc)(const char *name, long long val, void *privdata, RedisModuleString **err);
typedef int (*RedisModuleConfigSetBoolFunc)(const char *name, int val, void *privdata, RedisModuleString **err);
typedef int (*RedisModuleConfigSetEnumFunc)(const char *name, int val, void *privdata, RedisModuleString **err);
```
Modules can also specify an optional apply callback that will be called after
value(s) have been set via CONFIG SET:
```
typedef int (*RedisModuleConfigApplyFunc)(RedisModuleCtx *ctx, void *privdata, RedisModuleString **err);
```
**Flags:**
We expose 7 new flags to the module, which are used as part of the config registration.
```
#define REDISMODULE_CONFIG_MODIFIABLE 0 /* This is the default for a module config. */
#define REDISMODULE_CONFIG_IMMUTABLE (1ULL<<0) /* Can this value only be set at startup? */
#define REDISMODULE_CONFIG_SENSITIVE (1ULL<<1) /* Does this value contain sensitive information */
#define REDISMODULE_CONFIG_HIDDEN (1ULL<<4) /* This config is hidden in `config get <pattern>` (used for tests/debugging) */
#define REDISMODULE_CONFIG_PROTECTED (1ULL<<5) /* Becomes immutable if enable-protected-configs is enabled. */
#define REDISMODULE_CONFIG_DENY_LOADING (1ULL<<6) /* This config is forbidden during loading. */
/* Numeric Specific Configs */
#define REDISMODULE_CONFIG_MEMORY (1ULL<<7) /* Indicates if this value can be set as a memory value */
```
**Module Registration APIs**:
```
int (*RedisModule_RegisterBoolConfig)(RedisModuleCtx *ctx, char *name, int default_val, unsigned int flags, RedisModuleConfigGetBoolFunc getfn, RedisModuleConfigSetBoolFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
int (*RedisModule_RegisterNumericConfig)(RedisModuleCtx *ctx, const char *name, long long default_val, unsigned int flags, long long min, long long max, RedisModuleConfigGetNumericFunc getfn, RedisModuleConfigSetNumericFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
int (*RedisModule_RegisterStringConfig)(RedisModuleCtx *ctx, const char *name, const char *default_val, unsigned int flags, RedisModuleConfigGetStringFunc getfn, RedisModuleConfigSetStringFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
int (*RedisModule_RegisterEnumConfig)(RedisModuleCtx *ctx, const char *name, int default_val, unsigned int flags, const char **enum_values, const int *int_values, int num_enum_vals, RedisModuleConfigGetEnumFunc getfn, RedisModuleConfigSetEnumFunc setfn, RedisModuleConfigApplyFunc applyfn, void *privdata);
int (*RedisModule_LoadConfigs)(RedisModuleCtx *ctx);
```
The module name will be auto appended along with a "." to the front of the name of the config.
**What RM_Register[...]Config does**:
A RedisModule struct now keeps a list of ModuleConfig objects which look like:
```
typedef struct ModuleConfig {
sds name; /* Name of config without the module name appended to the front */
void *privdata; /* Optional data passed into the module config callbacks */
union get_fn { /* The get callback specificed by the module */
RedisModuleConfigGetStringFunc get_string;
RedisModuleConfigGetNumericFunc get_numeric;
RedisModuleConfigGetBoolFunc get_bool;
RedisModuleConfigGetEnumFunc get_enum;
} get_fn;
union set_fn { /* The set callback specified by the module */
RedisModuleConfigSetStringFunc set_string;
RedisModuleConfigSetNumericFunc set_numeric;
RedisModuleConfigSetBoolFunc set_bool;
RedisModuleConfigSetEnumFunc set_enum;
} set_fn;
RedisModuleConfigApplyFunc apply_fn;
RedisModule *module;
} ModuleConfig;
```
It also registers a standardConfig in the configs array, with a pointer to the
ModuleConfig object associated with it.
**What happens on a CONFIG GET/SET MODULENAME.MODULECONFIG:**
For CONFIG SET, we do the same parsing as is done in config.c and pass that
as the argument to the module set callback. For CONFIG GET, we call the
module get callback and return that value to config.c to return to a client.
**CONFIG REWRITE**:
Starting up a server with module configurations in a .conf file but no module load
directive will fail. The flip side is also true, specifying a module load and a bunch
of module configurations will load those configurations in using the module defined
set callbacks on a RM_LoadConfigs call. Configs being rewritten works the same
way as it does for standard configs, as the module has the ability to specify a
default value. If a module is unloaded with configurations specified in the .conf file
those configurations will be commented out from the .conf file on the next config rewrite.
**RM_LoadConfigs:**
`RedisModule_LoadConfigs(RedisModuleCtx *ctx);`
This last API is used to make configs available within the onLoad() after they have
been registered. The expected usage is that a module will register all of its configs,
then call LoadConfigs to trigger all of the set callbacks, and then can error out if any
of them were malformed. LoadConfigs will attempt to set all configs registered to
either a .conf file argument/loadex argument or their default value if an argument is
not specified. **LoadConfigs is a required function if configs are registered.
** Also note that LoadConfigs **does not** call the apply callbacks, but a module
can do that directly after the LoadConfigs call.
**New Command: MODULE LOADEX [CONFIG NAME VALUE] [ARGS ...]:**
This command provides the ability to provide startup context information to a module.
LOADEX stands for "load extended" similar to GETEX. Note that provided config
names need the full MODULENAME.MODULECONFIG name. Any additional
arguments a module might want are intended to be specified after ARGS.
Everything after ARGS is passed to onLoad as RedisModuleString **argv.
Co-authored-by: Madelyn Olson <madelyneolson@gmail.com>
Co-authored-by: Madelyn Olson <matolson@amazon.com>
Co-authored-by: sundb <sundbcn@gmail.com>
Co-authored-by: Madelyn Olson <34459052+madolson@users.noreply.github.com>
Co-authored-by: Oran Agra <oran@redislabs.com>
Co-authored-by: Yossi Gottlieb <yossigo@gmail.com>
The PR extends RM_Call with 3 new capabilities using new flags that
are given to RM_Call as part of the `fmt` argument.
It aims to assist modules that are getting a list of commands to be
executed from the user (not hard coded as part of the module logic),
think of a module that implements a new scripting language...
* `S` - Run the command in a script mode, this means that it will raise an
error if a command which are not allowed inside a script (flaged with the
`deny-script` flag) is invoked (like SHUTDOWN). In addition, on script mode,
write commands are not allowed if there is not enough good replicas (as
configured with `min-replicas-to-write`) and/or a disk error happened.
* `W` - no writes mode, Redis will reject any command that is marked with `write`
flag. Again can be useful to modules that implement a new scripting language
and wants to prevent any write commands.
* `E` - Return errors as RedisModuleCallReply. Today the errors that happened
before the command was invoked (like unknown commands or acl error) return
a NULL reply and set errno. This might be missing important information about
the failure and it is also impossible to just pass the error to the user using
RM_ReplyWithCallReply. This new flag allows you to get a RedisModuleCallReply
object with the relevant error message and treat it as if it was an error that was
raised by the command invocation.
Tests were added to verify the new code paths.
In addition small refactoring was done to share some code between modules,
scripts, and `processCommand` function:
1. `getAclErrorMessage` was added to `acl.c` to unified to log message extraction
from the acl result
2. `checkGoodReplicasStatus` was added to `replication.c` to check the status of
good replicas. It is used on `scriptVerifyWriteCommandAllow`, `RM_Call`, and
`processCommand`.
3. `writeCommandsGetDiskErrorMessage` was added to `server.c` to get the error
message on persistence failure. Again it is used on `scriptVerifyWriteCommandAllow`,
`RM_Call`, and `processCommand`.
When ::singledb is 0, we will use db 9 for the test db.
Since ::singledb is set to 1 in the cluster-related tests, but not restored, some subsequent
tests associated with db 9 will fail.
The new module redact test will fail with valgrind:
```
[err]: modules can redact arguments in tests/unit/moduleapi/auth.tcl
Expected 'slowlog reset' to be equal to 'auth.redact 1 (redacted) 3 (redacted)' (context: type eval line 12 cmd {assert_equal {slowlog reset} [lindex [lindex [r slowlog get] 2] 3]} proc ::test)
```
The reason is that with `slowlog-log-slower-than 10000`,
`slowlog get` will have a chance to exceed 10ms.
Made two changes to avoid failure:
1. change `slowlog-log-slower-than` from 10000 to -1, distable it.
2. assert to use the previous execution result.
In theory, the second one can actually be left unchanged, but i
think it will be better if it is changed.
Deleting a stream while a client is blocked XREADGROUP should unblock the client.
The idea is that if a client is blocked via XREADGROUP is different from
any other blocking type in the sense that it depends on the existence of both
the key and the group. Even if the key is deleted and then revived with XADD
it won't help any clients blocked on XREADGROUP because the group no longer
exist, so they would fail with -NOGROUP anyway.
The conclusion is that it's better to unblock these clients (with error) upon
the deletion of the key, rather than waiting for the first XADD.
Other changes:
1. Slightly optimize all `serveClientsBlockedOn*` functions by checking `server.blocked_clients_by_type`
2. All `serveClientsBlockedOn*` functions now use a list iterator rather than looking at `listFirst`, relying
on `unblockClient` to delete the head of the list. Before this commit, only `serveClientsBlockedOnStreams`
used to work like that.
3. bugfix: CLIENT UNBLOCK ERROR should work even if the command doesn't have a timeout_callback
(only relevant to module commands)
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.
