Images are too large to be sent over waku/whisper with the
current PoW (0.002).
This commit lowers the PoW for sending messages to a lower value,
depending on the size.
This means that older clients will not be able to receive messages that
are greater than 50KB (none of the messages we currently send is anywhere close to
that, most of them are less than 1KB).
I would have preferred to set the PoW explicitly for images to be lower,
but it's not trivial as we use `datasync` to send messages and its
interface takes a payload that is to be dispatched and a function to
dispatch, at initialization stage.
This make it difficult (impossible?) to set a different PoW for a
particular message, without changing function signature in datasync
(which is agnostic to the transport used).
So a less cumbersome approach is to just fingerprint on size.
This commit does a few things:
1) Handle membership updates using protobuf and adds the relevant
endpoints.
2) Store in memory a map of chats + contacts for faster lookups, which
are then flushed to disk on each update
3) Validate incoming messages
Sorry for the large pr, but you know, v1 :)
* Use a single Message type `v1/message.go` and `message.go` are the same now, and they embed `protobuf.ChatMessage`
* Use `SendChatMessage` for sending chat messages, this is basically the old `Send` but a bit more flexible so we can send different message types (stickers,commands), and not just text.
* Remove dedup from services/shhext. Because now we process in status-protocol, dedup makes less sense, as those messages are going to be processed anyway, so removing for now, we can re-evaluate if bringing it to status-go or not.
* Change the various retrieveX method to a single one:
`RetrieveAll` will be processing those messages that it can process (Currently only `Message`), and return the rest in `RawMessages` (still transit). The format for the response is:
`Chats`: -> The chats updated by receiving the message
`Messages`: -> The messages retrieved (already matched to a chat)
`Contacts`: -> The contacts updated by the messages
`RawMessages` -> Anything else that can't be parsed, eventually as we move everything to status-protocol-go this will go away.
Andrea Maria Piana
Adam Babik
Pedro Pombeiro