Streaming parts of the string

[hubertlepicki]

I don't think this is currently supported, but a nice feature to have would be to be able to stream parts of the string fields that are within JSON.

For example, I now am dealing with a GMail API calls, that allow us to download attachments. Unfortunately these are either protobufs or JSON-encoded, base64-encoded strings.

So we download files like this:

{
  "size": 12345,
  "data": "this is some very long base64-encoded string here, possibly around 30MB in size"
}

I have currently hacked together a dead simple parser that skips ahead in file to appropriate section (using ugh, regexp and binary pattern matching), but it would be actually pretty awesome to properly parse such stream and receive the value of "data" attribute in chunks.