[PULL 08/14] qcow2.py: Introduce '-j' key to dump in JSON format

[Eric Blake <eblake@redhat.com>]

From: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>

Add the command key to the qcow2.py arguments list to dump QCOW2
metadata in JSON format. Here is the suggested way to do that. The
implementation of the dump in JSON format is in the patch that follows.

Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1596742557-320265-9-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 tests/qemu-iotests/qcow2.py        | 18 ++++++++++++++----
 tests/qemu-iotests/qcow2_format.py |  4 ++--
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/tests/qemu-iotests/qcow2.py b/tests/qemu-iotests/qcow2.py
index 0910e6ac0705..77ca59cc663d 100755
--- a/tests/qemu-iotests/qcow2.py
+++ b/tests/qemu-iotests/qcow2.py
@@ -26,16 +26,19 @@ from qcow2_format import (
 )


+is_json = False
+
+
 def cmd_dump_header(fd):
     h = QcowHeader(fd)
-    h.dump()
+    h.dump(is_json)
     print()
-    h.dump_extensions()
+    h.dump_extensions(is_json)


 def cmd_dump_header_exts(fd):
     h = QcowHeader(fd)
-    h.dump_extensions()
+    h.dump_extensions(is_json)


 def cmd_set_header(fd, name, value):
@@ -151,11 +154,14 @@ def main(filename, cmd, args):


 def usage():
-    print("Usage: %s <file> <cmd> [<arg>, ...]" % sys.argv[0])
+    print("Usage: %s <file> <cmd> [<arg>, ...] [<key>, ...]" % sys.argv[0])
     print("")
     print("Supported commands:")
     for name, handler, num_args, desc in cmds:
         print("    %-20s - %s" % (name, desc))
+    print("")
+    print("Supported keys:")
+    print("    %-20s - %s" % ('-j', 'Dump in JSON format'))


 if __name__ == '__main__':
@@ -163,4 +169,8 @@ if __name__ == '__main__':
         usage()
         sys.exit(1)

+    is_json = '-j' in sys.argv
+    if is_json:
+        sys.argv.remove('-j')
+
     main(sys.argv[1], sys.argv[2], sys.argv[3:])
diff --git a/tests/qemu-iotests/qcow2_format.py b/tests/qemu-iotests/qcow2_format.py
index 574249bc463c..de0adcbf9db0 100644
--- a/tests/qemu-iotests/qcow2_format.py
+++ b/tests/qemu-iotests/qcow2_format.py
@@ -109,7 +109,7 @@ class Qcow2Struct(metaclass=Qcow2StructMeta):
         self.__dict__ = dict((field[2], values[i])
                              for i, field in enumerate(self.fields))

-    def dump(self):
+    def dump(self, is_json=False):
         for f in self.fields:
             value = self.__dict__[f[2]]
             if isinstance(f[1], str):
@@ -408,7 +408,7 @@ class QcowHeader(Qcow2Struct):
         buf = buf[0:header_bytes-1]
         fd.write(buf)

-    def dump_extensions(self):
+    def dump_extensions(self, is_json=False):
         for ex in self.extensions:
             print('Header extension:')
             ex.dump()
-- 
2.28.0