[Qemu-devel] [PATCH] Hack qmp.py to support reading a JSON multi-line response

["Daniel P. Berrange" <berrange@redhat.com>]

From: "Daniel P. Berrange" <berrange@redhat.com>

The qmp-shell code assumes the JSON response is only on a single
line. If the QEMU monitor is configured in "pretty print" mode
the JSON response can be multi-line. The basic Python JSON APIs
do not appear to support a streaming mode, so the simple hack
here is to try parsing a line, and if it fails, then read another
line, append it, and try parsing again. Keep reading lines until
we can successfully parse

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 QMP/qmp.py | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/QMP/qmp.py b/QMP/qmp.py
index 36ecc1d..464a01a 100644
--- a/QMP/qmp.py
+++ b/QMP/qmp.py
@@ -61,10 +61,18 @@ class QEMUMonitorProtocol:
 
     def __json_read(self, only_event=False):
         while True:
-            data = self.__sockfile.readline()
-            if not data:
-                return
-            resp = json.loads(data)
+            data = ""
+            while True:
+                moredata = self.__sockfile.readline()
+                if not moredata:
+                    return
+                data = data + moredata
+                try:
+                    resp = json.loads(data)
+                    break
+                except ValueError:
+                    pass
+
             if 'event' in resp:
                 self.__events.append(resp)
                 if not only_event:
-- 
1.7.11.2