binder.py 5.97 KB
Newer Older
1
2
3
4
# Tweepy
# Copyright 2009 Joshua Roesslein
# See LICENSE

5
import httplib
Josh Roesslein's avatar
Josh Roesslein committed
6
import urllib
7
import time
8

Josh Roesslein's avatar
Josh Roesslein committed
9
10
from . parsers import parse_error
from . error import TweepError
11

12
13
14
15
16
17
18
19
20
21
22
try:
    import json #Python >= 2.6
except ImportError:
    try:
        import simplejson as json #Python < 2.6
    except ImportError:
        try:
            from django.utils import simplejson as json #Google App Engine
        except ImportError:
            raise ImportError, "Can't load a json library"

Josh Roesslein's avatar
Josh Roesslein committed
23

24
25
def bind_api(path, parser, allowed_param=None, method='GET', require_auth=False,
              timeout=None, host=None):
26

Josh Roesslein's avatar
Josh Roesslein committed
27
28
29
30
31
32
33
34
35
36
37
38
    def _call(api, *args, **kargs):
        # If require auth, throw exception if credentials not provided
        if require_auth and not api.auth_handler:
            raise TweepError('Authentication required!')

        # check for post_data parameter
        if 'post_data' in kargs:
            post_data = kargs['post_data']
            del kargs['post_data']
        else:
            post_data = None

39
40
41
42
43
44
45
46
47
48
49
50
        # check for retry request parameters
        if 'retry_count' in kargs:
            retry_count = kargs['retry_count']
            del kargs['retry_count']
        else:
            retry_count = 0
        if 'retry_delay' in kargs:
            retry_delay = kargs['retry_delay']
            del kargs['retry_delay']
        else:
            retry_delay = 0

Josh Roesslein's avatar
Josh Roesslein committed
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
        # check for headers
        if 'headers' in kargs:
            headers = dict(kargs['headers'])
            del kargs['headers']
        else:
            headers = {}

        # build parameter dict
        if allowed_param:
            parameters = {}
            for idx, arg in enumerate(args):
                try:
                    parameters[allowed_param[idx]] = arg
                except IndexError:
                    raise TweepError('Too many parameters supplied!')
            for k, arg in kargs.items():
                if arg is None:
                    continue
                if k in parameters:
                    raise TweepError('Multiple values for parameter %s supplied!' % k)
                if k not in allowed_param:
                    raise TweepError('Invalid parameter %s supplied!' % k)
                parameters[k] = arg
74
        else:
Josh Roesslein's avatar
Josh Roesslein committed
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
            if len(args) > 0 or len(kargs) > 0:
                raise TweepError('This method takes no parameters!')
            parameters = None

        # Build url with parameters
        if parameters:
            url = '%s?%s' % (api.api_root + path, urllib.urlencode(parameters))
        else:
            url = api.api_root + path

        # Check cache if caching enabled and method is GET
        if api.cache and method == 'GET':
            cache_result = api.cache.get(url, timeout)
            # if cache result found and not expired, return it
            if cache_result:
                # must restore api reference
                if isinstance(cache_result, list):
                    for result in cache_result:
                        result._api = api
                else:
                    cache_result._api = api
                return cache_result

98
        # get scheme and host
Josh Roesslein's avatar
Josh Roesslein committed
99
        if api.secure:
100
            scheme = 'https://'
Josh Roesslein's avatar
Josh Roesslein committed
101
        else:
102
103
            scheme = 'http://'
        _host = host or api.host
Josh Roesslein's avatar
Josh Roesslein committed
104

105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
        # Continue attempting request until successful
        # or maxium number of retries is reached.
        retries_performed = 0
        while retries_performed < retry_count + 1:
            # Open connection
            # FIXME: add timeout
            if api.secure:
                conn = httplib.HTTPSConnection(_host)
            else:
                conn = httplib.HTTPConnection(_host)

            # Apply authentication
            if api.auth_handler:
                api.auth_handler.apply_auth(
                        scheme + _host + url,
                        method, headers, parameters
                )

            # Build request
            conn.request(method, url, headers=headers, body=post_data)

            # Get response
            resp = conn.getresponse()

            # If request was successful, quit the loop
            if resp.status == 200:
                break

            # Sleep before retrying request again
            time.sleep(retry_delay)
            retries_performed += 1
Josh Roesslein's avatar
Josh Roesslein committed
136
137

        # If an error was returned, throw an exception
138
        api.last_response = resp
Josh Roesslein's avatar
Josh Roesslein committed
139
140
141
142
143
144
145
        if resp.status != 200:
            try:
                error_msg = parse_error(resp.read())
            except Exception:
                error_msg = "Twitter error response: status code = %s" % resp.status
            raise TweepError(error_msg)

146
147
148
149
150
151
        # Parse json respone body
        try:
            jobject = json.loads(resp.read())
        except Exception:
            raise TweepError("Failed to parse json response text")

152
153
154
155
156
157
158
159
        # Parse cursor infomation
        if isinstance(jobject, dict):
            next_cursor = jobject.get('next_cursor')
            prev_cursor = jobject.get('previous_cursor')
        else:
            next_cursor = None
            prev_cursor = None

160
        # Pass json object into parser
161
        try:
162
163
164
165
            if next_cursor is not None and prev_cursor is not None:
                out = parser(jobject, api), next_cursor, prev_cursor
            else:
                out = parser(jobject, api)
166
        except Exception:
167
            raise TweepError("Failed to parse json object")
168

Josh Roesslein's avatar
Josh Roesslein committed
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
        conn.close()

        # validate result
        if api.validate:
            # list of results
            if isinstance(out, list) and len(out) > 0:
                if hasattr(out[0], 'validate'):
                    for result in out:
                        result.validate()
            # single result
            else:
                if hasattr(out, 'validate'):
                    out.validate()

        # store result in cache
        if api.cache and method == 'GET':
            api.cache.store(url, out)

        return out

189
190
191
    # Expose extra data in callable object
    _call.allowed_param = allowed_param

Josh Roesslein's avatar
Josh Roesslein committed
192
193
    return _call