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diff --git a/iredis/data/commands/function-load.md b/iredis/data/commands/function-load.md new file mode 100644 index 0000000..16f125b --- /dev/null +++ b/iredis/data/commands/function-load.md @@ -0,0 +1,36 @@ +Load a library to Redis. + +The command's gets a single mandatory parameter which is the source code that implements the library. +The library payload must start with Shebang statement that provides a metadata about the library (like the engine to use and the library name). +Shebang format: `#!<engine name> name=<library name>`. Currently engine name must be `lua`. + +For the Lua engine, the implementation should declare one or more entry points to the library with the [`redis.register_function()` API](/topics/lua-api#redis.register_function). +Once loaded, you can call the functions in the library with the `FCALL` (or `FCALL_RO` when applicable) command. + +When attempting to load a library with a name that already exists, the Redis server returns an error. +The `REPLACE` modifier changes this behavior and overwrites the existing library with the new contents. + +The command will return an error in the following circumstances: + +* An invalid _engine-name_ was provided. +* The library's name already exists without the `REPLACE` modifier. +* A function in the library is created with a name that already exists in another library (even when `REPLACE` is specified). +* The engine failed in creating the library's functions (due to a compilation error, for example). +* No functions were declared by the library. + +For more information please refer to [Introduction to Redis Functions](/topics/functions-intro). + +@return + +@string - the library name that was loaded + +@examples + +The following example will create a library named `mylib` with a single function, `myfunc`, that returns the first argument it gets. + +``` +redis> FUNCTION LOAD "#!lua name=mylib \n redis.register_function('myfunc', function(keys, args) return args[1] end)" +mylib +redis> FCALL myfunc 0 hello +"hello" +``` |