7eadc5ee70
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.
Redis Test Suite
The normal execution mode of the test suite involves starting and manipulating
local redis-server instances, inspecting process state, log files, etc.
The test suite also supports execution against an external server, which is
enabled using the --host and --port parameters. When executing against an
external server, tests tagged external:skip are skipped.
There are additional runtime options that can further adjust the test suite to match different external server configurations:
| Option | Impact |
|---|---|
--singledb |
Only use database 0, don't assume others are supported. |
--ignore-encoding |
Skip all checks for specific encoding. |
--ignore-digest |
Skip key value digest validations. |
--cluster-mode |
Run in strict Redis Cluster compatibility mode. |
--large-memory |
Enables tests that consume more than 100mb |
Tags
Tags are applied to tests to classify them according to the subsystem they test, but also to indicate compatibility with different run modes and required capabilities.
Tags can be applied in different context levels:
start_servercontexttagscontext that bundles several tests together- A single test context.
The following compatibility and capability tags are currently used:
| Tag | Indicates |
|---|---|
external:skip |
Not compatible with external servers. |
cluster:skip |
Not compatible with --cluster-mode. |
large-memory |
Test that requires more than 100mb |
tls:skip |
Not campatible with --tls. |
needs:repl |
Uses replication and needs to be able to SYNC from server. |
needs:debug |
Uses the DEBUG command or other debugging focused commands (like OBJECT). |
needs:pfdebug |
Uses the PFDEBUG command. |
needs:config-maxmemory |
Uses CONFIG SET to manipulate memory limit, eviction policies, etc. |
needs:config-resetstat |
Uses CONFIG RESETSTAT to reset statistics. |
needs:reset |
Uses RESET to reset client connections. |
needs:save |
Uses SAVE to create an RDB file. |
When using an external server (--host and --port), filtering using the
external:skip tags is done automatically.
When using --cluster-mode, filtering using the cluster:skip tag is done
automatically.
When not using --large-memory, filtering using the largemem:skip tag is done
automatically.
In addition, it is possible to specify additional configuration. For example, to
run tests on a server that does not permit SYNC use:
./runtest --host <host> --port <port> --tags -needs:repl