1# Copyright (c) The OpenTracing Authors.
2#
3# Permission is hereby granted, free of charge, to any person obtaining a copy
4# of this software and associated documentation files (the "Software"), to deal
5# in the Software without restriction, including without limitation the rights
6# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7# copies of the Software, and to permit persons to whom the Software is
8# furnished to do so, subject to the following conditions:
9#
10# The above copyright notice and this permission notice shall be included in
11# all copies or substantial portions of the Software.
12#
13# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
19# THE SOFTWARE.
20
21from __future__ import absolute_import
22
23from opentracing import SpanContextCorruptedException
24
25from .context import SpanContext
26from .propagator import Propagator
27
28prefix_tracer_state = 'ot-tracer-'
29prefix_baggage = 'ot-baggage-'
30field_name_trace_id = prefix_tracer_state + 'traceid'
31field_name_span_id = prefix_tracer_state + 'spanid'
32field_count = 2
33
34
35class TextPropagator(Propagator):
36    """A MockTracer Propagator for Format.TEXT_MAP."""
37
38    def inject(self, span_context, carrier):
39        carrier[field_name_trace_id] = '{0:x}'.format(span_context.trace_id)
40        carrier[field_name_span_id] = '{0:x}'.format(span_context.span_id)
41        if span_context.baggage is not None:
42            for k in span_context.baggage:
43                carrier[prefix_baggage+k] = span_context.baggage[k]
44
45    def extract(self, carrier):  # noqa
46        count = 0
47        span_id, trace_id = (0, 0)
48        baggage = {}
49        for k in carrier:
50            v = carrier[k]
51            k = k.lower()
52            if k == field_name_span_id:
53                span_id = int(v, 16)
54                count += 1
55            elif k == field_name_trace_id:
56                trace_id = int(v, 16)
57                count += 1
58            elif k.startswith(prefix_baggage):
59                baggage[k[len(prefix_baggage):]] = v
60
61        if count != field_count:
62            raise SpanContextCorruptedException()
63
64        return SpanContext(
65            span_id=span_id,
66            trace_id=trace_id,
67            baggage=baggage)
68