Is It Possible To Use Gzip Compression With Server-sent Events (sse)?

I would like to know if it is possible to enable gzip compression for Server-Sent Events (SSE ; Content-Type: text/event-stream). It seems it is possible, according to this book: h

Solution 1:

TL;DR: If the requests are not cached, you likely want to use zlib and declare Content-Encoding to be 'deflate'. That change alone should make your code work.

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If you declare Content-Encoding to be gzip, you need to actually use gzip. They are based on the the same compression algorithm, but gzip has some extra framing. This works, for example:

import gzip
importStringIO
from bottle import response, route
@route('/')
def get_data():
    response.add_header("Content-Encoding", "gzip")
    s = StringIO.StringIO()
    with gzip.GzipFile(fileobj=s, mode='w') asf:
        f.write('Hello World')
    return s.getvalue()

That only really makes sense if you use an actual file as a cache, though.

Solution 2:

There's also middleware you can use so you don't need to worry about gzipping responses for each of your methods. Here's one I used recently.

https://code.google.com/p/ibkon-wsgi-gzip-middleware/

This is how I used it (I'm using bottle.py with the gevent server)

from gzip_middleware import Gzipper
importbottleapp= Gzipper(bottle.app())
run(app = app, host='0.0.0.0', port=8080, server='gevent')

For this particular library, you can set w/c types of responses you want to compress by modifying the DEFAULT_COMPRESSABLES variable for example

DEFAULT_COMPRESSABLES = set(['text/plain', 'text/html', 'text/css',
'application/json', 'application/x-javascript', 'text/xml',
'application/xml', 'application/xml+rss', 'text/javascript',     
'image/gif'])

All responses go through the middleware and get gzipped without modifying your existing code. By default, it compresses responses whose content-type belongs to DEFAULT_COMPRESSABLES and whose content-length is greater than 200 characters.