MySQL Bugs: #73802: Easier loading of plugins

Bug #73802	Easier loading of plugins
Submitted:	4 Sep 2014 8:38	Modified:	8 Mar 2018 11:59
Reporter:	Daniël van Eeden (OCA)	Email Updates:
Status:	Open	Impact on me:	None
Category:	MySQL Server: User-defined functions ( UDF )	Severity:	S4 (Feature request)
Version:	8.0	OS:	Any
Assigned to:	Georgi Kodinov	CPU Architecture:	Any
Tags:	plugin, usability

Description:

- Many plugins have more than one function. Loading all functions takes one statement per function. This is errorprone.
- Loading plugins on Windows or Linux/UNIX is different (.so vs. .dll)

See also: Bug #71263

How to repeat:
Try to load the plugins for
- enterprise thread pool
- json functions
- enterprise encryption
- enterprise audit
- additional storage engines
- InnoDB memcached plugin

Suggested fix:
myplugin.json:
{
  "Name": "My Plugin",
  "Version": "0.1",
  "URL": "https://example.com/foo_func/",
  "License": "GPL",
  "install":
    "Windows": { 
      "foo_func": "foo_func.dll",
      "bar_func": "bar_func.dll"
    }, 
    "Generic": { 
      "foo_func": "foo_func.so",
      "bar_func": "bar_func.so"
    }
  },
  "after_install": "myfunc_tables.sql"
}

INSTALL PLUGIN FROM myplugin.json;

Maybe also use the DOAP standard in addition.

The json should also have return types and supported mysql versions. (Maybe load a different plugin for a different version (e.g. for common_schema or the sys schema)

The json could be read by workbench and then load the plugins in older versions of mysql which do not yet have support for the json plugin loading.

maybe show plugins could read the json files and show not-yet-loaded plugins.

Thank you for the reasonable feature request.

This also could make enabling semisync and group_replication easier.

added tags and changed version

Would a combination of making an daemon plugin (https://dev.mysql.com/doc/refman/8.0/en/writing-daemon-plugins.html) holding the UDFs and the UDF registration API (https://dev.mysql.com/doc/dev/mysql-server/latest/udf__registration_8h.html) as accessible through the registry plugin service (https://dev.mysql.com/doc/refman/8.0/en/component-plugin-services.html) will fit the bill ? 

The idea is not just have the UDFs in a shared object, but instead also have a daemon plugin (for the init/deinit functions) and have these functions register/unregister all of the UDFs in the shared object.

In this way you will need a single command INSTALL PLUGUIN to install all of your UDFs.

If you think this is a good enough work-around please close the bug as fixed.

That sounds nice, but it wouldn't work for pure-sql extensions like mysql-sys (ps_helper) or common_schema (by Shlomi Noach).

And how would that work for plugins which need to run some sql? (rewriter plugin and memcached plugin)

Also this would still need a different command on Windows (.dll) and BSD (.so).

True, if you do it as a plugin. 
But if you do it as a component, INSTALL COMPONENT does not need the shared object extension.

Daniël,

Would a component registering/unregistering a bunch of UDFs via the service work for you ?

It might.