File: protozero-trace.hh

package info (click to toggle)
pdns-recursor 5.3.3-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 11,116 kB
  • sloc: cpp: 109,650; javascript: 20,651; python: 5,657; sh: 5,094; makefile: 780; ansic: 582; xml: 37
file content (781 lines) | stat: -rw-r--r-- 27,645 bytes parent folder | download | duplicates (2)
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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
/*
 * This file is part of PowerDNS or dnsdist.
 * Copyright -- PowerDNS.COM B.V. and its contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * In addition, for the avoidance of any doubt, permission is granted to
 * link this program with OpenSSL and to (re)distribute the binaries
 * produced as the result of such linking.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#pragma once

#include <array>
#include <variant>
#include <vector>

#include <protozero/pbf_reader.hpp>
#include <protozero/pbf_writer.hpp>

#include "dns_random.hh"
#include "ednsoptions.hh"

// See https://github.com/open-telemetry/opentelemetry-proto/tree/main/opentelemetry/proto

namespace pdns::trace
{

// https://github.com/open-telemetry/opentelemetry-proto/blob/main/opentelemetry/proto/common/v1/common.proto

struct AnyValue;
struct ArrayValue;
struct KeyValue;
struct KeyValueList;

inline void encode(protozero::pbf_writer& writer, uint8_t field, bool value, bool always = false)
{
  if (always || value) {
    writer.add_bool(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, uint32_t value, bool always = false)
{
  if (always || value != 0) {
    writer.add_uint32(field, value);
  }
}

inline void encodeFixed(protozero::pbf_writer& writer, uint8_t field, uint32_t value)
{
  if (value != 0) {
    writer.add_fixed32(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, int64_t value, bool always = false)
{
  if (always || value != 0) {
    writer.add_int64(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, uint64_t value, bool always = false)
{
  if (always || value != 0) {
    writer.add_uint64(field, value);
  }
}

inline void encodeFixed(protozero::pbf_writer& writer, uint8_t field, uint64_t value)
{
  if (value != 0) {
    writer.add_fixed64(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, double value, bool always = false)
{
  if (always || value != 0.0) {
    writer.add_double(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, const std::string& value, bool always = false)
{
  if (always || !value.empty()) {
    writer.add_string(field, value);
  }
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, const std::vector<uint8_t>& value, bool always = false)
{
  if (always || !value.empty()) {
    writer.add_bytes(field, reinterpret_cast<const char*>(value.data()), value.size()); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast) it's the API
  }
}

template <typename T>
void encode(protozero::pbf_writer& writer, const std::vector<T>& vec)
{
  for (auto const& element : vec) {
    element.encode(writer);
  }
}

template <typename T>
void encode(protozero::pbf_writer& writer, uint8_t field, const std::vector<T>& vec)
{
  for (auto const& element : vec) {
    protozero::pbf_writer sub{writer, field};
    element.encode(sub);
  }
}

template <typename T, typename E>
T decode(protozero::pbf_reader& reader)
{
  std::vector<E> vec;
  while (reader.next()) {
    if (reader.tag() == 1) {
      protozero::pbf_reader sub = reader.get_message();
      vec.emplace_back(E::decode(sub));
    }
  }
  return {std::move(vec)};
}

struct ArrayValue
{
  std::vector<AnyValue> values{}; // = 1

  void encode(protozero::pbf_writer& writer) const
  {
    pdns::trace::encode(writer, 1, values);
  }

  static ArrayValue decode(protozero::pbf_reader& reader);

  bool operator==(const ArrayValue& rhs) const
  {
    return values == rhs.values;
  }
};

struct KeyValueList
{
  std::vector<KeyValue> values{}; // = 1

  void encode(protozero::pbf_writer& writer) const
  {
    pdns::trace::encode(writer, 1, values);
  }

  static KeyValueList decode(protozero::pbf_reader& reader);

  bool operator==(const KeyValueList& rhs) const
  {
    return values == rhs.values;
  }
};

using NoValue = char;
struct AnyValue : public std::variant<NoValue, std::string, bool, int64_t, double, ArrayValue, KeyValueList, std::vector<uint8_t>>
{
  void encode(protozero::pbf_writer& writer) const;
  static AnyValue decode(protozero::pbf_reader& reader);
};

struct EntityRef
{
  std::string schema_url{}; // == 1
  std::string type{}; // == 2
  std::vector<std::string> id_keys{}; // == 3
  std::vector<std::string> description_keys{}; // == 4

  void encode(protozero::pbf_writer& writer) const;
  static EntityRef decode(protozero::pbf_reader& reader);
};

struct KeyValue
{
  std::string key{}; // = 1
  AnyValue value{}; // = 2
  void encode(protozero::pbf_writer& writer) const;
  static KeyValue decode(protozero::pbf_reader& reader);

  bool operator==(const KeyValue& rhs) const
  {
    return key == rhs.key && value == rhs.value;
  }
};

struct Resource
{
  std::vector<KeyValue> attributes{}; // = 1
  uint32_t dropped_attributes_count{0}; // = 2;
  std::vector<EntityRef> entity_refs{}; // = 3

  void encode(protozero::pbf_writer& writer) const;
  static Resource decode(protozero::pbf_reader& reader);
};

struct InstrumentationScope
{
  std::string name{}; // = 1
  std::string version{}; // = 2
  std::vector<KeyValue> attributes{}; // = 3
  uint32_t dropped_attributes_count{0}; // = 4

  void encode(protozero::pbf_writer& writer) const;
  static InstrumentationScope decode(protozero::pbf_reader& reader);
};

using TraceID = std::array<uint8_t, 16>;
using SpanID = std::array<uint8_t, 8>;

inline void random(TraceID& trace)
{
  dns_random(trace.data(), trace.size());
}

inline void random(SpanID& span)
{
  dns_random(span.data(), span.size());
}

inline void clear(TraceID& trace)
{
  trace.fill(0);
}

inline void clear(SpanID& span)
{
  span.fill(0);
}

inline void fill(TraceID& trace, const std::string& data)
{
  if (data.size() != trace.size()) {
    throw std::runtime_error("TraceID size mismatch");
  }
  std::copy(data.begin(), data.end(), trace.begin());
}

inline void fill(SpanID& span, const std::string& data)
{
  if (data.size() != span.size()) {
    throw std::runtime_error("SpanID size mismatch");
  }
  std::copy(data.begin(), data.end(), span.begin());
}

inline void fill(TraceID& trace, const char* data, size_t size)
{
  fill(trace, std::string(data, size));
}

inline void fill(SpanID& span, const char* data, size_t size)
{
  fill(span, std::string(data, size));
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, const TraceID& value)
{
  writer.add_bytes(field, reinterpret_cast<const char*>(value.data()), value.size()); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast) it's the API
}

inline TraceID decodeTraceID(protozero::pbf_reader& reader)
{
  TraceID bytes;
  const auto data = reader.get_view();
  const auto len = std::min(bytes.size(), data.size());
  std::copy(data.data(), data.data() + len, bytes.begin()); // NOLINT(cppcoreguidelines-pro-bounds-pointer-arithmetic)
  return bytes;
}

inline void encode(protozero::pbf_writer& writer, uint8_t field, const SpanID& value)
{
  writer.add_bytes(field, reinterpret_cast<const char*>(value.data()), value.size()); // NOLINT(cppcoreguidelines-pro-type-reinterpret-cast) it's the API
}

inline SpanID decodeSpanID(protozero::pbf_reader& reader)
{
  SpanID bytes;
  const auto data = reader.get_view();
  const auto len = std::min(bytes.size(), data.size());
  std::copy(data.data(), data.data() + len, bytes.begin()); // NOLINT(cppcoreguidelines-pro-bounds-pointer-arithmetic)
  return bytes;
}

// The Status type defines a logical error model that is suitable for different
// programming environments, including REST APIs and RPC APIs.
struct Status
{
  // A developer-facing human readable error message.
  std::string message{}; // = 2;

  // For the semantics of status codes see
  // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/api.md#set-status
  enum class StatusCode : uint8_t
  {
    // The default status.
    STATUS_CODE_UNSET = 0,
    // The Span has been validated by an Application developer or Operator to
    // have completed successfully.
    STATUS_CODE_OK = 1,
    // The Span contains an error.
    STATUS_CODE_ERROR = 2,
  };

  // The status code.
  StatusCode code{StatusCode::STATUS_CODE_UNSET}; //  = 3;

  void clear()
  {
    message.clear();
    code = StatusCode::STATUS_CODE_UNSET;
  }
  void encode(protozero::pbf_writer& writer) const;
  static Status decode(protozero::pbf_reader& reader);
};

inline uint64_t timestamp()
{
  timespec now{};
  clock_gettime(CLOCK_REALTIME, &now);
  return (1000000000ULL * now.tv_sec) + now.tv_nsec;
}

// This struct is used to store the info of the initial span. As it is passed around resolving
// queries, it needs to be as small as possible, hence no full Span.
struct InitialSpanInfo
{
  TraceID trace_id{};
  SpanID span_id{};
  SpanID parent_span_id{};
  uint64_t start_time_unix_nano{0};

  void clear()
  {
    pdns::trace::clear(trace_id);
    pdns::trace::clear(span_id);
    pdns::trace::clear(parent_span_id);
    start_time_unix_nano = 0;
  }
};

struct Span
{
  // A unique identifier for a trace. All spans from the same trace share
  // the same `trace_id`. The ID is a 16-byte array. An ID with all zeroes OR
  // of length other than 16 bytes is considered invalid (empty string in OTLP/JSON
  // is zero-length and thus is also invalid).
  //
  // This field is required.
  TraceID trace_id{}; // = 1
  // A unique identifier for a span within a trace, assigned when the span
  // is created. The ID is an 8-byte array. An ID with all zeroes OR of length
  // other than 8 bytes is considered invalid (empty string in OTLP/JSON
  // is zero-length and thus is also invalid).
  //
  // This field is required.
  SpanID span_id{}; // = 2
  // trace_state conveys information about request position in multiple distributed tracing graphs.
  // It is a trace_state in w3c-trace-context format: https://www.w3.org/TR/trace-context/#tracestate-header
  // See also https://github.com/w3c/distributed-tracing for more details about this field.
  std::string trace_state{}; // = 3
  // The `span_id` of this span's parent span. If this is a root span, then this
  // field must be empty. The ID is an 8-byte array.
  SpanID parent_span_id{}; // = 4
  // A description of the span's operation.
  //
  // For example, the name can be a qualified method name or a file name
  // and a line number where the operation is called. A best practice is to use
  // the same display name at the same call point in an application.
  // This makes it easier to correlate spans in different traces.
  //
  // This field is semantically required to be set to non-empty string.
  // Empty value is equivalent to an unknown span name.
  //
  // This field is required.
  std::string name{}; // = 5

  // SpanKind is the type of span. Can be used to specify additional relationships between spans
  // in addition to a parent/child relationship.
  enum class SpanKind : uint8_t
  {
    // Unspecified. Do NOT use as default.
    // Implementations MAY assume SpanKind to be INTERNAL when receiving UNSPECIFIED.
    SPAN_KINUNSPECIFIED = 0,
    // Indicates that the span represents an internal operation within an application,
    // as opposed to an operation happening at the boundaries. Default value.
    SPAN_KININTERNAL = 1,
    // Indicates that the span covers server-side handling of an RPC or other
    // remote network request.
    SPAN_KINSERVER = 2,
    // Indicates that the span describes a request to some remote service.
    SPAN_KINCLIENT = 3,
    // Indicates that the span describes a producer sending a message to a broker.
    // Unlike CLIENT and SERVER, there is often no direct critical path latency relationship
    // between producer and consumer spans. A PRODUCER span ends when the message was accepted
    // by the broker while the logical processing of the message might span a much longer time.
    SPAN_KINPRODUCER = 4,
    // Indicates that the span describes consumer receiving a message from a broker.
    // Like the PRODUCER kind, there is often no direct critical path latency relationship
    // between producer and consumer spans.
    SPAN_KINCONSUMER = 5,
  };
  // Distinguishes between spans generated in a particular context. For example,
  // two spans with the same name may be distinguished using `CLIENT` (caller)
  // and `SERVER` (callee) to identify queueing latency associated with the span.
  SpanKind kind{Span::SpanKind::SPAN_KINUNSPECIFIED}; // = 6
  // start_time_unix_nano is the start time of the span. On the client side, this is the time
  // kept by the local machine where the span execution starts. On the server side, this
  // is the time when the server's application handler starts running.
  // Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
  //
  // This field is semantically required and it is expected that end_time >= start_time.
  uint64_t start_time_unix_nano{0}; // = 7
  // end_time_unix_nano is the end time of the span. On the client side, this is the time
  // kept by the local machine where the span execution ends. On the server side, this
  // is the time when the server application handler stops running.
  // Value is UNIX Epoch time in nanoseconds since 00:00:00 UTC on 1 January 1970.
  //
  // This field is semantically required and it is expected that end_time >= start_time.
  uint64_t end_time_unix_nano{0}; // = 8
  // attributes is a collection of key/value pairs. Note, global attributes
  // like server name can be set using the resource API. Examples of attributes:
  //
  //     "/http/user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36"
  //     "/http/server_latency": 300
  //     "example.com/myattribute": true
  //     "example.com/score": 10.239
  //
  // The OpenTelemetry API specification further restricts the allowed value types:
  // https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/common/README.md#attribute
  // Attribute keys MUST be unique (it is not allowed to have more than one
  // attribute with the same key).
  std::vector<KeyValue> attributes{}; // = 9
  // dropped_attributes_count is the number of attributes that were discarded. Attributes
  // can be discarded because their keys are too long or because there are too many
  // attributes. If this value is 0, then no attributes were dropped.
  uint32_t dropped_attributes_count{0}; // = 10

  // Event is a time-stamped annotation of the span, consisting of user-supplied
  // text description and key-value pairs.x
  struct Event
  {
    // time_unix_nano is the time the event occurred.
    uint64_t time_unix_nano; // = 1
    // name of the event.
    // This field is semantically required to be set to non-empty string.
    std::string name; // = 2
    // attributes is a collection of attribute key/value pairs on the event.
    // Attribute keys MUST be unique (it is not allowed to have more than one
    // attribute with the same key).
    std::vector<KeyValue> attributes; // = 3
    // dropped_attributes_count is the number of dropped attributes. If the value is 0,
    // then no attributes were dropped.
    uint32_t dropped_attributes_count{0}; // = 4

    void encode(protozero::pbf_writer& writer) const;
    static Event decode(protozero::pbf_reader& reader);
  };
  // events is a collection of Event items.
  std::vector<Event> events{}; // = 11
  // dropped_events_count is the number of dropped events. If the value is 0, then no
  // events were dropped.
  uint32_t dropped_events_count{0}; // = 12

  // A pointer from the current span to another span in the same trace or in a
  // different trace. For example, this can be used in batching operations,
  // where a single batch handler processes multiple requests from different
  // traces or when the handler receives a request from a different project.
  struct Link
  {
    // A unique identifier of a trace that this linked span is part of. The ID is a
    // 16-byte array.
    TraceID trace_id; // = 1
    // A unique identifier for the linked span. The ID is an 8-byte array.
    SpanID span_id; // = 2
    // The trace_state associated with the link.
    std::string trace_state; // = 3
    // attributes is a collection of attribute key/value pairs on the link.
    // Attribute keys MUST be unique (it is not allowed to have more than one
    // attribute with the same key).
    std::vector<KeyValue> attributes; // = 4
    // dropped_attributes_count is the number of dropped attributes. If the value is 0,
    // then no attributes were dropped.
    uint32_t dropped_attributes_count{0}; // = 5
    // Flags, a bit field.
    //
    // Bits 0-7 (8 least significant bits) are the trace flags as defined in W3C Trace
    // Context specification. To read the 8-bit W3C trace flag, use
    // `flags & SPAN_FLAGS_TRACE_FLAGS_MASK`.
    //
    // See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
    //
    // Bits 8 and 9 represent the 3 states of whether the link is remote.
    // The states are (unknown, is not remote, is remote).
    // To read whether the value is known, use `(flags & SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK) != 0`.
    // To read whether the link is remote, use `(flags & SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK) != 0`.
    //
    // Readers MUST NOT assume that bits 10-31 (22 most significant bits) will be zero.
    // When creating new spans, bits 10-31 (most-significant 22-bits) MUST be zero.
    //
    // [Optional].
    uint32_t flags{0}; // = 6

    void encode(protozero::pbf_writer& writer) const;
    static Link decode(protozero::pbf_reader& reader);
  };
  std::vector<Link> links{}; // = 13
  uint32_t dropped_links_count{0}; // = 14
  Status status{}; // = 15

  // Flags, a bit field.
  //
  // Bits 0-7 (8 least significant bits) are the trace flags as defined in W3C Trace
  // Context specification. To read the 8-bit W3C trace flag, use
  // `flags & SPAN_FLAGS_TRACE_FLAGS_MASK`.
  //
  // See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
  //
  // Bits 8 and 9 represent the 3 states of whether a span's parent
  // is remote. The states are (unknown, is not remote, is remote).
  // To read whether the value is known, use `(flags & SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK) != 0`.
  // To read whether the span is remote, use `(flags & SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK) != 0`.
  //
  // When creating span messages, if the message is logically forwarded from another source
  // with an equivalent flags fields (i.e., usually another OTLP span message), the field SHOULD
  // be copied as-is. If creating from a source that does not have an equivalent flags field
  // (such as a runtime representation of an OpenTelemetry span), the high 22 bits MUST
  // be set to zero.
  // Readers MUST NOT assume that bits 10-31 (22 most significant bits) will be zero.
  //
  // [Optional].
  uint32_t flags{0}; // = 16;

  void close()
  {
    end_time_unix_nano = timestamp();
  }

  void clear()
  {
    pdns::trace::clear(trace_id); // 1
    pdns::trace::clear(span_id); // 2
    trace_state.clear(); // 3
    pdns::trace::clear(parent_span_id); // 4
    name.clear(); // 5
    kind = SpanKind::SPAN_KINUNSPECIFIED; // 6
    start_time_unix_nano = 0; // 7
    end_time_unix_nano = 0; // 8
    attributes.clear(); // 9
    dropped_attributes_count = 0; // 10
    events.clear(); // 11
    dropped_events_count = 0; // 12
    links.clear(); // 13
    dropped_links_count = 0; //14
    status.clear(); // 15
    flags = 0; // 16
  }
  void encode(protozero::pbf_writer& writer) const;
  static Span decode(protozero::pbf_reader& reader);
};

// SpanFlags represents constants used to interpret the
// Span.flags field, which is protobuf 'fixed32' type and is to
// be used as bit-fields. Each non-zero value defined in this enum is
// a bit-mask.  To extract the bit-field, for example, use an
// expression like:
//
//   (span.flags & SPAN_FLAGS_TRACE_FLAGS_MASK)
//
// See https://www.w3.org/TR/trace-context-2/#trace-flags for the flag definitions.
//
// Note that Span flags were introduced in version 1.1 of the
// OpenTelemetry protocol.  Older Span producers do not set this
// field, consequently consumers should not rely on the absence of a
// particular flag bit to indicate the presence of a particular feature.
enum class SpanFlags : uint16_t
{
  // The zero value for the enum. Should not be used for comparisons.
  // Instead use bitwise "and" with the appropriate mask as shown above.
  SPAN_FLAGS_DO_NOT_USE = 0,
  // Bits 0-7 are used for trace flags.
  SPAN_FLAGS_TRACE_FLAGS_MASK = 0x000000FF,
  // Bits 8 and 9 are used to indicate that the parent span or link span is remote.
  // Bit 8 (`HAS_IS_REMOTE`) indicates whether the value is known.
  // Bit 9 (`IS_REMOTE`) indicates whether the span or link is remote.
  SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK = 0x00000100,
  SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK = 0x00000200,
  // Bits 10-31 are reserved for future use.
};

// A collection of Spans produced by an InstrumentationScope.
struct ScopeSpans
{
  // The instrumentation scope information for the spans in this message.
  // Semantically when InstrumentationScope isn't set, it is equivalent with
  // an empty instrumentation scope name (unknown).
  InstrumentationScope scope{}; // = 1
  // A list of Spans that originate from an instrumentation scope.
  std::vector<Span> spans{}; // = 2
  // The Schema URL, if known. This is the identifier of the Schema that the span data
  // is recorded in. Notably, the last part of the URL path is the version number of the
  // schema: http[s]://server[:port]/path/<version>. To learn more about Schema URL see
  // https://opentelemetry.io/docs/specs/otel/schemas/#schema-url
  // This schema_url applies to all spans and span events in the "spans" field.
  std::string schema_url{}; // = 3

  void close()
  {
    for (auto& element : spans) {
      element.close();
    }
  }
  void encode(protozero::pbf_writer& writer) const;
  static ScopeSpans decode(protozero::pbf_reader& reader);
};

// A collection of ScopeSpans from a Resource.
struct ResourceSpans
{
  // The resource for the spans in this message.
  // If this field is not set then no resource info is known.
  Resource resource; // = 1
  // A list of ScopeSpans that originate from a resource.
  std::vector<ScopeSpans> scope_spans; // = 2
  // The Schema URL, if known. This is the identifier of the Schema that the resource data
  // is recorded in. Notably, the last part of the URL path is the version number of the
  // schema: http[s]://server[:port]/path/<version>. To learn more about Schema URL see
  // https://opentelemetry.io/docs/specs/otel/schemas/#schema-url
  // This schema_url applies to the data in the "resource" field. It does not apply
  // to the data in the "scope_spans" field which have their own schema_url field.
  std::string schema_url{}; // = 3

  void close()
  {
    for (auto& element : scope_spans) {
      element.close();
    }
  }
  void encode(protozero::pbf_writer& writer) const;
  static ResourceSpans decode(protozero::pbf_reader& reader);
};

// TracesData represents the traces data that can be stored in a persistent storage,
// OR can be embedded by other protocols that transfer OTLP traces data but do
// not implement the OTLP protocol.
//
// The main difference between this message and collector protocol is that
// in this message there will not be any "control" or "metadata" specific to
// OTLP protocol.
//
// When new fields are added into this message, the OTLP request MUST be updated
// as well.
struct TracesData
{
  // An array of ResourceSpans.
  // For data coming from a single resource this array will typically contain
  // one element. Intermediary nodes that receive data from multiple origins
  // typically batch the data before forwarding further and in that case this
  // array will contain multiple elements.
  std::vector<ResourceSpans> resource_spans; // = 1

  void close()
  {
    for (auto& element : resource_spans) {
      element.close();
    }
  }
  void encode(protozero::pbf_writer& writer) const;
  static TracesData decode(protozero::pbf_reader& reader);

  [[nodiscard]] std::string encode() const
  {
    std::string data;
    protozero::pbf_writer writer{data};
    encode(writer);
    return data;
  }

  static TracesData boilerPlate(std::string&& service, std::string&& req, std::vector<Span>&& spans)
  {
    spans.at(0).attributes.push_back({"arg", {std::move(req)}});
    return TracesData{
      .resource_spans = {pdns::trace::ResourceSpans{.resource = {.attributes = {{"service.name", {{std::move(service)}}}}}, .scope_spans = {{.spans = std::move(spans)}}}}};
  }
};

inline ArrayValue ArrayValue::decode(protozero::pbf_reader& reader)
{
  return pdns::trace::decode<ArrayValue, AnyValue>(reader);
}

inline KeyValueList KeyValueList::decode(protozero::pbf_reader& reader)
{
  return pdns::trace::decode<KeyValueList, KeyValue>(reader);
}

struct EDNSOTTraceRecord
{
  // 1 byte version, 1 byte reserved/alignment, 16 bytes traceid, optional 8 bytes spanid
  static constexpr size_t fullSize = 1 + 1 + 16 + 8;
  static constexpr size_t sizeNoSpanID = 1 + 1 + 16;
  static constexpr size_t traceIDOffset = 1 + 1;
  static constexpr size_t spanIDOffset = 1 + 1 + 16;

  EDNSOTTraceRecord(uint8_t* arg) :
    data(arg) {}
  // NOLINTBEGIN(cppcoreguidelines-pro-bounds-pointer-arithmetic)
  void setVersion(uint8_t version)
  {
    data[0] = version;
  }
  void setTraceID(const TraceID& traceid)
  {
    std::copy(traceid.begin(), traceid.end(), &data[traceIDOffset]);
  }
  void setSpanID(const SpanID& spanid)
  {
    std::copy(spanid.begin(), spanid.end(), &data[spanIDOffset]);
  }
  // NOLINTEND(cppcoreguidelines-pro-bounds-pointer-arithmetic)
private:
  uint8_t* data;
};

struct EDNSOTTraceRecordView
{
  EDNSOTTraceRecordView(const uint8_t* arg, size_t argsize) :
    data(arg), size(argsize) {}

  // NOLINTBEGIN(cppcoreguidelines-pro-bounds-pointer-arithmetic)
  [[nodiscard]] bool getVersion(uint8_t& version) const
  {
    if (size > 0) {
      version = data[0];
      return true;
    }
    return false;
  }
  [[nodiscard]] bool getTraceID(TraceID& traceid) const
  {
    if (size >= pdns::trace::EDNSOTTraceRecord::sizeNoSpanID) {
      std::copy(&data[EDNSOTTraceRecord::traceIDOffset], &data[EDNSOTTraceRecord::traceIDOffset + traceid.size()], traceid.begin());
      return true;
    }
    return false;
  }
  [[nodiscard]] bool getSpanID(SpanID& spanid) const
  {
    if (size == pdns::trace::EDNSOTTraceRecord::fullSize) {
      std::copy(&data[EDNSOTTraceRecord::spanIDOffset], &data[EDNSOTTraceRecord::spanIDOffset + spanid.size()], spanid.begin());
      return true;
    }
    return false;
  }
  // NOLINTEND(cppcoreguidelines-pro-bounds-pointer-arithmetic)
private:
  const uint8_t* const data;
  const size_t size;
};

void extractOTraceIDs(const EDNSOptionViewMap& map, pdns::trace::InitialSpanInfo& span);

} // namespace pdns::trace