Getting all field names from a protocol buffer?

Question

I want to get all the field names of a proto into a list. Is there a way to do this? I looked in the documentation and there doesn't seem to be anything for this.

Answer 1

Every proto class possess a DESCRIPTOR class variable that can be used to inspect the fields of corresponding protobuf messages.

Have a look at the documentation of the Descriptor and FieldDescriptor classes for more details.

Here is a simple example to get the FieldDescriptors of all the fields in message into a list:

res = message.DESCRIPTOR.fields

To get the names of the fields "exactly as they appear in the .proto file":

res = [field.name for field in message.DESCRIPTOR.fields]

or (from the comments):

res = message.DESCRIPTOR.fields_by_name.keys()

To get the full names of the fields "including containing scope":

res = [field.full_name for field in message.DESCRIPTOR.fields]

Answer 2

qfiard's answer didn't work for me. Calling message.DESCRIPTOR.fields.keys() produced AttributeError: 'list' object has no attribute 'keys'.

Not sure why it wouldn't work. Maybe it has something to do with how the message was defined/compiled.

The workaround was to do a list composition of the individual field objects and get the name property for each. This gave me a list of strings of all fields in this list.

res = [f.name for f in message.DESCRIPTOR.fields]

Note that this does not get you the field names within those fields recursively.

Answer 3

You can easily get a list of fields as follows

message_fields = [field for field in message.DESCRIPTOR.fields_by_name]