Revision: 4507 Author: russblau Date: 2007-11-05 15:13:10 +0000 (Mon, 05 Nov 2007)

Log Message: ----------- Generalize query method; add some response processing and error handling.

Modified Paths: -------------- branches/rewrite/pywikibot/data/api.py

Modified: branches/rewrite/pywikibot/data/api.py =================================================================== --- branches/rewrite/pywikibot/data/api.py 2007-11-05 10:23:03 UTC (rev 4506) +++ branches/rewrite/pywikibot/data/api.py 2007-11-05 15:13:10 UTC (rev 4507) @@ -12,17 +12,78 @@

import urllib import http +import simplejson as json +import warnings

+class APIError(Exception): + """The wiki site returned an error message.""" + def __init__(self, errordict): + """Save error dict returned by MW API.""" + self.errors = errordict

+ def __str__(self): + return "%(code)s: %(info)s" % self.errors + + class API:

def __init__(self, site): self.site = site

- def query(prop, **kwargs): - params = dict(kwargs) - params['action'] = 'query' + def request(self, **params): if not params.has_key('format'): #Most probably, we want the JSON format params['format'] = 'json' + return http.HTTP(None).POST('/w/api.php',params) #TODO: Use site's HTTP object instead

- return http.HTTP(None).POST('/w/api.php',params) #TODO: Use site's HTTP object instead + def query(self, **params): + if not params.has_key('action'): + params['action'] = 'query' + return self.request(**params) + + def query_response(self, **params): + """Submit a query and parse the response, returning a dict or None.""" + if params.has_key('format') and params['format'] != 'json': + raise TypeError("Query format '%s' cannot be parsed." % params['format']) + while True: + httpcode, rawdata = self.query(**params) + if httpcode != 200: + raise APIError( + {'code': httpcode, + 'info': "HTTP error code received.", + 'data': rawdata}) + if rawdata.startswith(u"unknown_action"): + e = {'code': data[:14], 'info': data[16:]} + raise APIError(e) + try: + result = json.loads(rawdata) + except ValueError: + # if the result isn't valid JSON, there must be a server + # problem. Wait a few seconds and try again + # TODO: implement a throttle + warnings.warn( +"Non-JSON response received from server %s; the server may be down." + % self.site) + continue + if type(result) is dict: + if result.has_key("error"): + # raise error + raise APIError(result['error']) + if result.has_key("query"): + return result + raise APIError( + {'code': "Unknown API error", + 'info': "Response received with no 'query' key.", + 'data': result}) + if type(result) is list: + if result == []: + return None + raise APIError( + {'code': "Unknown API error", + 'info': "Query returned a list instead of a dict.", + 'data': result}) + raise APIError( + {'code': "Unknown API error", + 'info': "Unable to process query response of type %s." + % type(result), + 'data': result}) +