The format is:
-{ "error": { "class": json-string, "data": json-object, "desc": json-string },
- "id": json-value }
+{ "error": { "class": json-string, "desc": json-string }, "id": json-value }
Where,
-- The "class" member contains the error class name (eg. "ServiceUnavailable")
-- The "data" member contains specific error data and is defined in a
- per-command basis, it will be an empty json-object if the error has no data
+- The "class" member contains the error class name (eg. "GenericError")
- The "desc" member is a human-readable error message. Clients should
not attempt to parse this message.
- The "id" member contains the transaction identification associated with
------------------
C: { "execute": }
-S: {"error": {"class": "JSONParsing", "desc": "Invalid JSON syntax", "data":
-{}}}
+S: {"error": {"class": "GenericError", "desc": "Invalid JSON syntax" } }
3.5 Powerdown event
-------------------
capabilities array (section '2.2 Server Greeting'). Thus, Clients can check
that array and enable the capabilities they support.
-Additionally, Clients must not assume any particular:
+The QMP Server performs a type check on the arguments to a command. It
+generates an error if a value does not have the expected type for its
+key, or if it does not understand a key that the Client included. The
+strictness of the Server catches wrong assumptions of Clients about
+the Server's schema. Clients can assume that, when such validation
+errors occur, they will be reported before the command generated any
+side effect.
-- Size of json-objects or length of json-arrays
+However, Clients must not assume any particular:
+
+- Length of json-arrays
+- Size of json-objects; in particular, future versions of QEMU may add
+ new keys and Clients should be able to ignore them.
- Order of json-object members or json-array elements
- Amount of errors generated by a command, that is, new errors can be added
to any existing command in newer versions of the Server
+Of course, the Server does guarantee to send valid JSON. But apart from
+this, a Client should be "conservative in what they send, and liberal in
+what they accept".
+
6. Downstream extension of QMP
------------------------------