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Diffstat (limited to 'docs')
| -rw-r--r-- | docs/qapi-code-gen.txt | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/docs/qapi-code-gen.txt b/docs/qapi-code-gen.txt index f6f8d33863..11f19cfa5f 100644 --- a/docs/qapi-code-gen.txt +++ b/docs/qapi-code-gen.txt @@ -103,6 +103,28 @@ And it looks like this on the wire: "data" : { "backing-file": "/some/place/my-image", "lazy-refcounts": true } } + +Flat union types avoid the nesting on the wire. They are used whenever a +specific field of the base type is declared as the discriminator ('type' is +then no longer generated). The discriminator must always be a string field. +The above example can then be modified as follows: + + { 'type': 'BlockdevCommonOptions', + 'data': { 'driver': 'str', 'readonly': 'bool' } } + { 'union': 'BlockdevOptions', + 'base': 'BlockdevCommonOptions', + 'discriminator': 'driver', + 'data': { 'raw': 'RawOptions', + 'qcow2': 'Qcow2Options' } } + +Resulting in this JSON object: + + { "driver": "qcow2", + "readonly": false, + "backing-file": "/some/place/my-image", + "lazy-refcounts": true } + + === Commands === Commands are defined by using a list containing three members. The first |