aboutsummaryrefslogtreecommitdiffstats
path: root/netlib/wsgi.py
blob: d6dfae5d166bb4dcc6a73377703df6a2ba4c00f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
from __future__ import (absolute_import, print_function, division)
from io import BytesIO, StringIO
import urllib
import time
import traceback

import six
from six.moves import urllib

from netlib.utils import always_bytes, native
from . import http, tcp

class ClientConn(object):

    def __init__(self, address):
        self.address = tcp.Address.wrap(address)


class Flow(object):

    def __init__(self, address, request):
        self.client_conn = ClientConn(address)
        self.request = request


class Request(object):

    def __init__(self, scheme, method, path, http_version, headers, content):
        self.scheme, self.method, self.path = scheme, method, path
        self.headers, self.content = headers, content
        self.http_version = http_version


def date_time_string():
    """Return the current date and time formatted for a message header."""
    WEEKS = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
    MONTHS = [
        None,
        'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
        'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'
    ]
    now = time.time()
    year, month, day, hh, mm, ss, wd, y_, z_ = time.gmtime(now)
    s = "%s, %02d %3s %4d %02d:%02d:%02d GMT" % (
        WEEKS[wd],
        day, MONTHS[month], year,
        hh, mm, ss
    )
    return s


class WSGIAdaptor(object):

    def __init__(self, app, domain, port, sversion):
        self.app, self.domain, self.port, self.sversion = app, domain, port, sversion

    def make_environ(self, flow, errsoc, **extra):
        path = native(flow.request.path, "latin-1")
        if '?' in path:
            path_info, query = native(path, "latin-1").split('?', 1)
        else:
            path_info = path
            query = ''
        environ = {
            'wsgi.version': (1, 0),
            'wsgi.url_scheme': native(flow.request.scheme, "latin-1"),
            'wsgi.input': BytesIO(flow.request.content or b""),
            'wsgi.errors': errsoc,
            'wsgi.multithread': True,
            'wsgi.multiprocess': False,
            'wsgi.run_once': False,
            'SERVER_SOFTWARE': self.sversion,
            'REQUEST_METHOD': native(flow.request.method, "latin-1"),
            'SCRIPT_NAME': '',
            'PATH_INFO': urllib.parse.unquote(path_info),
            'QUERY_STRING': query,
            'CONTENT_TYPE': native(flow.request.headers.get('Content-Type', ''), "latin-1"),
            'CONTENT_LENGTH': native(flow.request.headers.get('Content-Length', ''), "latin-1"),
            'SERVER_NAME': self.domain,
            'SERVER_PORT': str(self.port),
            'SERVER_PROTOCOL': native(flow.request.http_version, "latin-1"),
        }
        environ.update(extra)
        if flow.client_conn.address:
            environ["REMOTE_ADDR"] = native(flow.client_conn.address.host, "latin-1")
            environ["REMOTE_PORT"] = flow.client_conn.address.port

        for key, value in flow.request.headers.items():
            key = 'HTTP_' + native(key, "latin-1").upper().replace('-', '_')
            if key not in ('HTTP_CONTENT_TYPE', 'HTTP_CONTENT_LENGTH'):
                environ[key] = value
        return environ

    def error_page(self, soc, headers_sent, s):
        """
            Make a best-effort attempt to write an error page. If headers are
            already sent, we just bung the error into the page.
        """
        c = """
            <html>
                <h1>Internal Server Error</h1>
                <pre>{err}"</pre>
            </html>
        """.format(err=s).strip().encode()

        if not headers_sent:
            soc.write(b"HTTP/1.1 500 Internal Server Error\r\n")
            soc.write(b"Content-Type: text/html\r\n")
            soc.write("Content-Length: {length}\r\n".format(length=len(c)).encode())
            soc.write(b"\r\n")
        soc.write(c)

    def serve(self, request, soc, **env):
        state = dict(
            response_started=False,
            headers_sent=False,
            status=None,
            headers=None
        )

        def write(data):
            if not state["headers_sent"]:
                soc.write("HTTP/1.1 {status}\r\n".format(status=state["status"]).encode())
                headers = state["headers"]
                if 'server' not in headers:
                    headers["Server"] = self.sversion
                if 'date' not in headers:
                    headers["Date"] = date_time_string()
                soc.write(bytes(headers))
                soc.write(b"\r\n")
                state["headers_sent"] = True
            if data:
                soc.write(data)
            soc.flush()

        def start_response(status, headers, exc_info=None):
            if exc_info:
                if state["headers_sent"]:
                    six.reraise(*exc_info)
            elif state["status"]:
                raise AssertionError('Response already started')
            state["status"] = status
            state["headers"] = http.Headers([[always_bytes(k), always_bytes(v)] for k,v in headers])
            if exc_info:
                self.error_page(soc, state["headers_sent"], traceback.format_tb(exc_info[2]))
                state["headers_sent"] = True

        errs = six.BytesIO()
        try:
            dataiter = self.app(
                self.make_environ(request, errs, **env), start_response
            )
            for i in dataiter:
                write(i)
            if not state["headers_sent"]:
                write(b"")
        except Exception as e:
            try:
                s = traceback.format_exc()
                errs.write(s.encode("utf-8", "replace"))
                self.error_page(soc, state["headers_sent"], s)
            except Exception:    # pragma: no cover
                pass
        return errs.getvalue()