|
12 | 12 | # See the License for the specific language governing permissions and
|
13 | 13 | # limitations under the License.
|
14 | 14 |
|
15 |
| -""" |
16 |
| -AWS X-Ray Propagator |
17 |
| --------------------- |
| 15 | +from opentelemetry.propagators.aws.aws_xray_propagator import AwsXRayPropagator |
18 | 16 |
|
19 |
| -The **AWS X-Ray Propagator** provides a propagator that when used, adds a `trace |
20 |
| -header`_ to outgoing traces that is compatible with the AWS X-Ray backend service. |
21 |
| -This allows the trace context to be propagated when a trace spans multiple AWS |
22 |
| -services. |
23 |
| -
|
24 |
| -The same propagator setup is used to extract a context sent by external systems |
25 |
| -so that child span have the correct parent context. |
26 |
| -
|
27 |
| -**NOTE**: Because the parent context parsed from the ``X-Amzn-Trace-Id`` header |
28 |
| -assumes the context is _not_ sampled by default, users should make sure to add |
29 |
| -``Sampled=1`` to their ``X-Amzn-Trace-Id`` headers so that the child spans are |
30 |
| -sampled. |
31 |
| -
|
32 |
| -Usage |
33 |
| ------ |
34 |
| -
|
35 |
| -Use the provided AWS X-Ray Propagator to inject the necessary context into |
36 |
| -traces sent to external systems. |
37 |
| -
|
38 |
| -This can be done by either setting this environment variable: |
39 |
| -
|
40 |
| -:: |
41 |
| -
|
42 |
| - export OTEL_PROPAGATORS = xray |
43 |
| -
|
44 |
| -
|
45 |
| -Or by setting this propagator in your instrumented application: |
46 |
| -
|
47 |
| -.. code-block:: python |
48 |
| -
|
49 |
| - from opentelemetry.propagate import set_global_textmap |
50 |
| - from opentelemetry.propagators.aws import AwsXRayFormat |
51 |
| -
|
52 |
| - set_global_textmap(AwsXRayFormat()) |
53 |
| -
|
54 |
| -API |
55 |
| ---- |
56 |
| -.. _trace header: https://docs.aws.amazon.com/xray/latest/devguide/xray-concepts.html#xray-concepts-tracingheader |
57 |
| -""" |
58 |
| - |
59 |
| -import logging |
60 |
| -import typing |
61 |
| - |
62 |
| -from opentelemetry import trace |
63 |
| -from opentelemetry.context import Context |
64 |
| -from opentelemetry.propagators.textmap import ( |
65 |
| - CarrierT, |
66 |
| - Getter, |
67 |
| - Setter, |
68 |
| - TextMapPropagator, |
69 |
| - default_getter, |
70 |
| - default_setter, |
71 |
| -) |
72 |
| - |
73 |
| -TRACE_HEADER_KEY = "X-Amzn-Trace-Id" |
74 |
| -KV_PAIR_DELIMITER = ";" |
75 |
| -KEY_AND_VALUE_DELIMITER = "=" |
76 |
| - |
77 |
| -TRACE_ID_KEY = "Root" |
78 |
| -TRACE_ID_LENGTH = 35 |
79 |
| -TRACE_ID_VERSION = "1" |
80 |
| -TRACE_ID_DELIMITER = "-" |
81 |
| -TRACE_ID_DELIMITER_INDEX_1 = 1 |
82 |
| -TRACE_ID_DELIMITER_INDEX_2 = 10 |
83 |
| -TRACE_ID_FIRST_PART_LENGTH = 8 |
84 |
| - |
85 |
| -PARENT_ID_KEY = "Parent" |
86 |
| -PARENT_ID_LENGTH = 16 |
87 |
| - |
88 |
| -SAMPLED_FLAG_KEY = "Sampled" |
89 |
| -SAMPLED_FLAG_LENGTH = 1 |
90 |
| -IS_SAMPLED = "1" |
91 |
| -NOT_SAMPLED = "0" |
92 |
| - |
93 |
| - |
94 |
| -_logger = logging.getLogger(__name__) |
95 |
| - |
96 |
| - |
97 |
| -class AwsParseTraceHeaderError(Exception): |
98 |
| - def __init__(self, message): |
99 |
| - super().__init__() |
100 |
| - self.message = message |
101 |
| - |
102 |
| - |
103 |
| -class AwsXRayFormat(TextMapPropagator): |
104 |
| - """Propagator for the AWS X-Ray Trace Header propagation protocol. |
105 |
| -
|
106 |
| - See: https://docs.aws.amazon.com/xray/latest/devguide/xray-concepts.html#xray-concepts-tracingheader |
107 |
| - """ |
108 |
| - |
109 |
| - # AWS |
110 |
| - |
111 |
| - def extract( |
112 |
| - self, |
113 |
| - carrier: CarrierT, |
114 |
| - context: typing.Optional[Context] = None, |
115 |
| - getter: Getter = default_getter, |
116 |
| - ) -> Context: |
117 |
| - if context is None: |
118 |
| - context = Context() |
119 |
| - |
120 |
| - trace_header_list = getter.get(carrier, TRACE_HEADER_KEY) |
121 |
| - |
122 |
| - if not trace_header_list or len(trace_header_list) != 1: |
123 |
| - return context |
124 |
| - |
125 |
| - trace_header = trace_header_list[0] |
126 |
| - |
127 |
| - if not trace_header: |
128 |
| - return context |
129 |
| - |
130 |
| - try: |
131 |
| - ( |
132 |
| - trace_id, |
133 |
| - span_id, |
134 |
| - sampled, |
135 |
| - ) = AwsXRayFormat._extract_span_properties(trace_header) |
136 |
| - except AwsParseTraceHeaderError as err: |
137 |
| - _logger.debug(err.message) |
138 |
| - return context |
139 |
| - |
140 |
| - options = 0 |
141 |
| - if sampled: |
142 |
| - options |= trace.TraceFlags.SAMPLED |
143 |
| - |
144 |
| - span_context = trace.SpanContext( |
145 |
| - trace_id=trace_id, |
146 |
| - span_id=span_id, |
147 |
| - is_remote=True, |
148 |
| - trace_flags=trace.TraceFlags(options), |
149 |
| - trace_state=trace.TraceState(), |
150 |
| - ) |
151 |
| - |
152 |
| - if not span_context.is_valid: |
153 |
| - _logger.debug( |
154 |
| - "Invalid Span Extracted. Inserting INVALID span into provided context." |
155 |
| - ) |
156 |
| - return context |
157 |
| - |
158 |
| - return trace.set_span_in_context( |
159 |
| - trace.NonRecordingSpan(span_context), context=context |
160 |
| - ) |
161 |
| - |
162 |
| - @staticmethod |
163 |
| - def _extract_span_properties(trace_header): |
164 |
| - trace_id = trace.INVALID_TRACE_ID |
165 |
| - span_id = trace.INVALID_SPAN_ID |
166 |
| - sampled = False |
167 |
| - |
168 |
| - for kv_pair_str in trace_header.split(KV_PAIR_DELIMITER): |
169 |
| - try: |
170 |
| - key_str, value_str = kv_pair_str.split(KEY_AND_VALUE_DELIMITER) |
171 |
| - key, value = key_str.strip(), value_str.strip() |
172 |
| - except ValueError as ex: |
173 |
| - raise AwsParseTraceHeaderError( |
174 |
| - ( |
175 |
| - "Error parsing X-Ray trace header. Invalid key value pair: %s. Returning INVALID span context.", |
176 |
| - kv_pair_str, |
177 |
| - ) |
178 |
| - ) from ex |
179 |
| - if key == TRACE_ID_KEY: |
180 |
| - if not AwsXRayFormat._validate_trace_id(value): |
181 |
| - raise AwsParseTraceHeaderError( |
182 |
| - ( |
183 |
| - "Invalid TraceId in X-Ray trace header: '%s' with value '%s'. Returning INVALID span context.", |
184 |
| - TRACE_HEADER_KEY, |
185 |
| - trace_header, |
186 |
| - ) |
187 |
| - ) |
188 |
| - |
189 |
| - try: |
190 |
| - trace_id = AwsXRayFormat._parse_trace_id(value) |
191 |
| - except ValueError as ex: |
192 |
| - raise AwsParseTraceHeaderError( |
193 |
| - ( |
194 |
| - "Invalid TraceId in X-Ray trace header: '%s' with value '%s'. Returning INVALID span context.", |
195 |
| - TRACE_HEADER_KEY, |
196 |
| - trace_header, |
197 |
| - ) |
198 |
| - ) from ex |
199 |
| - elif key == PARENT_ID_KEY: |
200 |
| - if not AwsXRayFormat._validate_span_id(value): |
201 |
| - raise AwsParseTraceHeaderError( |
202 |
| - ( |
203 |
| - "Invalid ParentId in X-Ray trace header: '%s' with value '%s'. Returning INVALID span context.", |
204 |
| - TRACE_HEADER_KEY, |
205 |
| - trace_header, |
206 |
| - ) |
207 |
| - ) |
208 |
| - |
209 |
| - try: |
210 |
| - span_id = AwsXRayFormat._parse_span_id(value) |
211 |
| - except ValueError as ex: |
212 |
| - raise AwsParseTraceHeaderError( |
213 |
| - ( |
214 |
| - "Invalid TraceId in X-Ray trace header: '%s' with value '%s'. Returning INVALID span context.", |
215 |
| - TRACE_HEADER_KEY, |
216 |
| - trace_header, |
217 |
| - ) |
218 |
| - ) from ex |
219 |
| - elif key == SAMPLED_FLAG_KEY: |
220 |
| - if not AwsXRayFormat._validate_sampled_flag(value): |
221 |
| - raise AwsParseTraceHeaderError( |
222 |
| - ( |
223 |
| - "Invalid Sampling flag in X-Ray trace header: '%s' with value '%s'. Returning INVALID span context.", |
224 |
| - TRACE_HEADER_KEY, |
225 |
| - trace_header, |
226 |
| - ) |
227 |
| - ) |
228 |
| - |
229 |
| - sampled = AwsXRayFormat._parse_sampled_flag(value) |
230 |
| - |
231 |
| - return trace_id, span_id, sampled |
232 |
| - |
233 |
| - @staticmethod |
234 |
| - def _validate_trace_id(trace_id_str): |
235 |
| - return ( |
236 |
| - len(trace_id_str) == TRACE_ID_LENGTH |
237 |
| - and trace_id_str.startswith(TRACE_ID_VERSION) |
238 |
| - and trace_id_str[TRACE_ID_DELIMITER_INDEX_1] == TRACE_ID_DELIMITER |
239 |
| - and trace_id_str[TRACE_ID_DELIMITER_INDEX_2] == TRACE_ID_DELIMITER |
240 |
| - ) |
241 |
| - |
242 |
| - @staticmethod |
243 |
| - def _parse_trace_id(trace_id_str): |
244 |
| - timestamp_subset = trace_id_str[ |
245 |
| - TRACE_ID_DELIMITER_INDEX_1 + 1 : TRACE_ID_DELIMITER_INDEX_2 |
246 |
| - ] |
247 |
| - unique_id_subset = trace_id_str[ |
248 |
| - TRACE_ID_DELIMITER_INDEX_2 + 1 : TRACE_ID_LENGTH |
249 |
| - ] |
250 |
| - return int(timestamp_subset + unique_id_subset, 16) |
251 |
| - |
252 |
| - @staticmethod |
253 |
| - def _validate_span_id(span_id_str): |
254 |
| - return len(span_id_str) == PARENT_ID_LENGTH |
255 |
| - |
256 |
| - @staticmethod |
257 |
| - def _parse_span_id(span_id_str): |
258 |
| - return int(span_id_str, 16) |
259 |
| - |
260 |
| - @staticmethod |
261 |
| - def _validate_sampled_flag(sampled_flag_str): |
262 |
| - return len( |
263 |
| - sampled_flag_str |
264 |
| - ) == SAMPLED_FLAG_LENGTH and sampled_flag_str in ( |
265 |
| - IS_SAMPLED, |
266 |
| - NOT_SAMPLED, |
267 |
| - ) |
268 |
| - |
269 |
| - @staticmethod |
270 |
| - def _parse_sampled_flag(sampled_flag_str): |
271 |
| - return sampled_flag_str[0] == IS_SAMPLED |
272 |
| - |
273 |
| - def inject( |
274 |
| - self, |
275 |
| - carrier: CarrierT, |
276 |
| - context: typing.Optional[Context] = None, |
277 |
| - setter: Setter = default_setter, |
278 |
| - ) -> None: |
279 |
| - span = trace.get_current_span(context=context) |
280 |
| - |
281 |
| - span_context = span.get_span_context() |
282 |
| - if not span_context.is_valid: |
283 |
| - return |
284 |
| - |
285 |
| - otel_trace_id = f"{span_context.trace_id:032x}" |
286 |
| - xray_trace_id = TRACE_ID_DELIMITER.join( |
287 |
| - [ |
288 |
| - TRACE_ID_VERSION, |
289 |
| - otel_trace_id[:TRACE_ID_FIRST_PART_LENGTH], |
290 |
| - otel_trace_id[TRACE_ID_FIRST_PART_LENGTH:], |
291 |
| - ] |
292 |
| - ) |
293 |
| - |
294 |
| - parent_id = f"{span_context.span_id:016x}" |
295 |
| - |
296 |
| - sampling_flag = ( |
297 |
| - IS_SAMPLED |
298 |
| - if span_context.trace_flags & trace.TraceFlags.SAMPLED |
299 |
| - else NOT_SAMPLED |
300 |
| - ) |
301 |
| - |
302 |
| - # TODO: Add OT trace state to the X-Ray trace header |
303 |
| - |
304 |
| - trace_header = KV_PAIR_DELIMITER.join( |
305 |
| - [ |
306 |
| - KEY_AND_VALUE_DELIMITER.join([key, value]) |
307 |
| - for key, value in [ |
308 |
| - (TRACE_ID_KEY, xray_trace_id), |
309 |
| - (PARENT_ID_KEY, parent_id), |
310 |
| - (SAMPLED_FLAG_KEY, sampling_flag), |
311 |
| - ] |
312 |
| - ] |
313 |
| - ) |
314 |
| - |
315 |
| - setter.set( |
316 |
| - carrier, TRACE_HEADER_KEY, trace_header, |
317 |
| - ) |
318 |
| - |
319 |
| - @property |
320 |
| - def fields(self): |
321 |
| - """Returns a set with the fields set in `inject`.""" |
322 |
| - |
323 |
| - return {TRACE_HEADER_KEY} |
| 17 | +__all__ = ["AwsXRayPropagator"] |
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