Ability to define whether response body is saved based on ContentType/StatusCode/Path

[robbiewareham]

To reduce the amount of IO and maximize performance, there could be a simple rules engine that allows us to define which response bodies we are interested in via a combination of ContentType/StatusCode/Path.

e.g.

Capture response bodies for all paths and content type if the status code > 399

Capture response body if JSON, status code < 399 and path = "/path/I/am/interested/in"

[wkeeling]

Thinking out loud here: I propose using interceptors for this purpose. They give ultimate flexibility in terms of what attributes of a request can be interrogated. We'd need to introduce a new attribute on the request and response to indicate whether the body should be captured or not, e.g. capture_body. Once that's been done, we should be able to do such things as:

def interceptor(req, res):
    if res.status_code > 399:
        res.capture_body = False

driver.interceptor = interceptor
driver.get(...)

and

def interceptor(req, res):
    if req.path == '/path/I/am/interested/in' \
           and res.headers['Content-Type'] == 'application/json' \
           and res.status_code < 399:
        res.capture_body = False

driver.interceptor = interceptor
driver.get(...)