[Qemu-devel] RFC: Full introspection support for QMP

[Amos Kong]

Hi all,

We already have query-command-line-options to query details of command-line
options. As we discussed in the list, we also need full introspection of QMP
(command). The qmp-events also need to be dumped, we can define events in
qai-schema.json. We can also dump QMP errors in future if it's needed.

Command name: query-qmp-schema
Return: returns the contents of qapi-schema.json in json format.

Solution to query json content from C code:
  qapi-schema.json is processed by qapi python scripts to generate C
  files, I found the content is good enough for Libvirt to know the
  QMP command schema. We can change qapi scripts to generate a talbe/list
  to record the raw string, then we can return the raw string in
  qmp_query_qmp_schema().

By default, return the complete schema in one go.

And support to query of unknown type in new command.
  -> { "execute": "query-qmp-schema" "arguments": { "command": "query-status" }}
  <- { "return" : "data": { "command': "query-status", "returns": "StatusInfo" 
}}
  -> { "execute": "query-qmp-schema" "arguments": { "type": "StatusInfo" }}
  <- { "return" : "data": { "type": "StatusInfo", "data": {"running": "bool",
                            "singlestep": "bool", "status": "RunState"} }
  -> { "execute": "query-qmp-schema" "arguments": { "event": "RX-FILTER-CHANGE" 
}}
  

Welcome your comments, thanks!


Target: 1.6
Related RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=557939

-- 
                        Amos.