How to assign to repeated field?

Question

I am using protocol buffers in python and I have a Person message

repeated uint64 id

but when I try to assign a value to it like:

person.id = [1, 32, 43432]

I get an error: Assigment not allowed for repeated field "id" in protocol message object How to assign a value to a repeated field ?

Answer 1

As per the documentation, you aren't able to directly assign to a repeated field. In this case, you can call extend to add all of the elements in the list to the field.

person.id.extend([1, 32, 43432])

Answer 2

If you don't want to extend but overwrite it completely, you can do:

person.id[:] = [1, 32, 43432]

This approach will also work to clear the field entirely:

del person.id[:]

Answer 3

For repeated composite types this is what worked for me.

del person.things[:]
person.things.extend([thing1, thing2, ..])

taken from these comments How to assign to repeated field? How to assign to repeated field?

Answer 4

You can try using MergeFrom

Check out these docs for the full list of Message methods available to you: https://developers.google.com/protocol-buffers/docs/reference/python/google.protobuf.message.Message-class