Debug logging support

Logger watches a [classsession] and logs the HTTP traffic that it generates, for debugging purposes. Many applications use an environment variable to determine whether or not to use Logger, and to determine the amount of debugging output.

To use Logger, first create a logger with [ctorlogger.new], optionally configure it with [methodlogger.set_request_filter], [methodlogger.set_response_filter], and [methodlogger.set_printer], and then attach it to a session (or multiple sessions) with [methodsession.add_feature].

By default, the debugging output is sent to stdout, and looks something like:

> POST /unauth HTTP/1.1
> Soup-Debug-Timestamp: 1200171744
> Soup-Debug: SoupSession 1 (0x612190), SoupMessage 1 (0x617000), GSocket 1 (0x612220)
> Host: localhost
> Content-Type: text/plain
> Connection: close

< HTTP/1.1 201 Created
< Soup-Debug-Timestamp: 1200171744
< Soup-Debug: SoupMessage 1 (0x617000)
< Date: Sun, 12 Jan 2008 21:02:24 GMT
< Content-Length: 0

The Soup-Debug-Timestamp line gives the time (as a time_t) when the request was sent, or the response fully received.

The Soup-Debug line gives further debugging information about the [classsession], [classmessage], and Socket involved; the hex numbers are the addresses of the objects in question (which may be useful if you are running in a debugger). The decimal IDs are simply counters that uniquely identify objects across the lifetime of the Logger. In particular, this can be used to identify when multiple messages are sent across the same connection.

Currently, the request half of the message is logged just before the first byte of the request gets written to the network (from the signalmessage[starting] signal).

The response is logged just after the last byte of the response body is read from the network (from the signalmessage[gotBody] or signalmessage[gotInformational] signal), which means that the signalmessage[gotHeaders] signal, and anything triggered off it (such as Message::authenticate) will be emitted *before* the response headers are actually logged.

If the response doesn't happen to trigger the signalmessage[gotBody] nor signalmessage[gotInformational] signals due to, for example, a cancellation before receiving the last byte of the response body, the response will still be logged on the event of the signalmessage[finished] signal.

Click to display all available methods, including inherited ones

The level of logging output.

If [propertylogger:level] is LoggerLogLevelBody, this gives the maximum number of bytes of the body that will be logged. (-1 means "no limit".)