cloudflare/pint
Publicmirrored from https://github.com/cloudflare/pintAvailable
internal/parser/parser.go
587lines · modecode
| 1 | package parser |
| 2 | |
| 3 | import ( |
| 4 | "bytes" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | "io" |
| 8 | "strings" |
| 9 | |
| 10 | "gopkg.in/yaml.v3" |
| 11 | |
| 12 | "github.com/prometheus/common/model" |
| 13 | |
| 14 | "github.com/cloudflare/pint/internal/comments" |
| 15 | ) |
| 16 | |
| 17 | const ( |
| 18 | recordKey = "record" |
| 19 | exprKey = "expr" |
| 20 | labelsKey = "labels" |
| 21 | alertKey = "alert" |
| 22 | forKey = "for" |
| 23 | keepFiringForKey = "keep_firing_for" |
| 24 | annotationsKey = "annotations" |
| 25 | ) |
| 26 | |
| 27 | var ErrRuleCommentOnFile = errors.New("this comment is only valid when attached to a rule") |
| 28 | |
| 29 | func NewParser() Parser { |
| 30 | return Parser{} |
| 31 | } |
| 32 | |
| 33 | type Parser struct{} |
| 34 | |
| 35 | func (p Parser) Parse(content []byte) (rules []Rule, err error) { |
| 36 | if len(content) == 0 { |
| 37 | return nil, nil |
| 38 | } |
| 39 | |
| 40 | defer func() { |
| 41 | if r := recover(); r != nil { |
| 42 | err = fmt.Errorf("unable to parse YAML file: %s", r) |
| 43 | } |
| 44 | }() |
| 45 | |
| 46 | var documents []yaml.Node |
| 47 | dec := yaml.NewDecoder(bytes.NewReader(content)) |
| 48 | for { |
| 49 | var doc yaml.Node |
| 50 | decodeErr := dec.Decode(&doc) |
| 51 | if errors.Is(decodeErr, io.EOF) { |
| 52 | break |
| 53 | } |
| 54 | if decodeErr != nil { |
| 55 | return nil, decodeErr |
| 56 | } |
| 57 | documents = append(documents, doc) |
| 58 | } |
| 59 | |
| 60 | for _, doc := range documents { |
| 61 | rules = append(rules, parseNode(content, &doc, 0)...) |
| 62 | } |
| 63 | return rules, err |
| 64 | } |
| 65 | |
| 66 | func parseNode(content []byte, node *yaml.Node, offset int) (rules []Rule) { |
| 67 | ret, isEmpty := parseRule(content, node, offset) |
| 68 | if !isEmpty { |
| 69 | rules = append(rules, ret) |
| 70 | return rules |
| 71 | } |
| 72 | |
| 73 | var rule Rule |
| 74 | for _, root := range node.Content { |
| 75 | // nolint: exhaustive |
| 76 | switch root.Kind { |
| 77 | case yaml.SequenceNode: |
| 78 | for _, n := range root.Content { |
| 79 | rules = append(rules, parseNode(content, n, offset)...) |
| 80 | } |
| 81 | case yaml.MappingNode: |
| 82 | rule, isEmpty = parseRule(content, root, offset) |
| 83 | if !isEmpty { |
| 84 | rules = append(rules, rule) |
| 85 | } else { |
| 86 | for _, n := range root.Content { |
| 87 | rules = append(rules, parseNode(content, n, offset)...) |
| 88 | } |
| 89 | } |
| 90 | case yaml.ScalarNode: |
| 91 | if root.Value != string(content) { |
| 92 | c := []byte(root.Value) |
| 93 | var n yaml.Node |
| 94 | if err := yaml.Unmarshal(c, &n); err == nil { |
| 95 | rules = append(rules, parseNode(c, &n, offset+root.Line)...) |
| 96 | } |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | return rules |
| 101 | } |
| 102 | |
| 103 | func parseRule(content []byte, node *yaml.Node, offset int) (rule Rule, _ bool) { |
| 104 | if node.Kind != yaml.MappingNode { |
| 105 | return rule, true |
| 106 | } |
| 107 | |
| 108 | var recordPart *YamlNode |
| 109 | var exprPart *PromQLExpr |
| 110 | var labelsPart *YamlMap |
| 111 | |
| 112 | var alertPart *YamlNode |
| 113 | var forPart *YamlNode |
| 114 | var keepFiringForPart *YamlNode |
| 115 | var annotationsPart *YamlMap |
| 116 | |
| 117 | var recordNode *yaml.Node |
| 118 | var alertNode *yaml.Node |
| 119 | var exprNode *yaml.Node |
| 120 | var forNode *yaml.Node |
| 121 | var keepFiringForNode *yaml.Node |
| 122 | var labelsNode *yaml.Node |
| 123 | var annotationsNode *yaml.Node |
| 124 | labelsNodes := map[*yaml.Node]*yaml.Node{} |
| 125 | annotationsNodes := map[*yaml.Node]*yaml.Node{} |
| 126 | |
| 127 | var key *yaml.Node |
| 128 | unknownKeys := []*yaml.Node{} |
| 129 | |
| 130 | var lines LineRange |
| 131 | |
| 132 | var ruleComments []comments.Comment |
| 133 | |
| 134 | for i, part := range unpackNodes(node) { |
| 135 | if lines.First == 0 || part.Line+offset < lines.First { |
| 136 | lines.First = part.Line + offset |
| 137 | } |
| 138 | lines.Last = max(lines.Last, part.Line+offset) |
| 139 | |
| 140 | if i == 0 && node.HeadComment != "" && part.HeadComment == "" { |
| 141 | part.HeadComment = node.HeadComment |
| 142 | } |
| 143 | if i == 0 && node.LineComment != "" && part.LineComment == "" { |
| 144 | part.LineComment = node.LineComment |
| 145 | } |
| 146 | if i == len(node.Content)-1 && node.FootComment != "" && part.HeadComment == "" { |
| 147 | part.FootComment = node.FootComment |
| 148 | } |
| 149 | for _, s := range mergeComments(part) { |
| 150 | for _, c := range comments.Parse(part.Line, s) { |
| 151 | if comments.IsRuleComment(c.Type) { |
| 152 | ruleComments = append(ruleComments, c) |
| 153 | } |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | if i%2 == 0 { |
| 158 | key = part |
| 159 | } else { |
| 160 | switch key.Value { |
| 161 | case recordKey: |
| 162 | if recordPart != nil { |
| 163 | return duplicatedKeyError(lines, part.Line+offset, recordKey) |
| 164 | } |
| 165 | recordNode = part |
| 166 | recordPart = newYamlNodeWithKey(key, part, offset) |
| 167 | lines.Last = max(lines.Last, recordPart.Lines.Last) |
| 168 | case alertKey: |
| 169 | if alertPart != nil { |
| 170 | return duplicatedKeyError(lines, part.Line+offset, alertKey) |
| 171 | } |
| 172 | alertNode = part |
| 173 | alertPart = newYamlNodeWithKey(key, part, offset) |
| 174 | lines.Last = max(lines.Last, alertPart.Lines.Last) |
| 175 | case exprKey: |
| 176 | if exprPart != nil { |
| 177 | return duplicatedKeyError(lines, part.Line+offset, exprKey) |
| 178 | } |
| 179 | exprNode = part |
| 180 | exprPart = newPromQLExpr(key, part, offset) |
| 181 | lines.Last = max(lines.Last, exprPart.Value.Lines.Last) |
| 182 | case forKey: |
| 183 | if forPart != nil { |
| 184 | return duplicatedKeyError(lines, part.Line+offset, forKey) |
| 185 | } |
| 186 | forNode = part |
| 187 | forPart = newYamlNodeWithKey(key, part, offset) |
| 188 | lines.Last = max(lines.Last, forPart.Lines.Last) |
| 189 | case keepFiringForKey: |
| 190 | if keepFiringForPart != nil { |
| 191 | return duplicatedKeyError(lines, part.Line+offset, keepFiringForKey) |
| 192 | } |
| 193 | keepFiringForNode = part |
| 194 | keepFiringForPart = newYamlNodeWithKey(key, part, offset) |
| 195 | lines.Last = max(lines.Last, keepFiringForPart.Lines.Last) |
| 196 | case labelsKey: |
| 197 | if labelsPart != nil { |
| 198 | return duplicatedKeyError(lines, part.Line+offset, labelsKey) |
| 199 | } |
| 200 | labelsNode = part |
| 201 | labelsNodes = mappingNodes(part) |
| 202 | labelsPart = newYamlMap(key, part, offset) |
| 203 | lines.Last = max(lines.Last, labelsPart.Lines.Last) |
| 204 | case annotationsKey: |
| 205 | if annotationsPart != nil { |
| 206 | return duplicatedKeyError(lines, part.Line+offset, annotationsKey) |
| 207 | } |
| 208 | annotationsNode = part |
| 209 | annotationsNodes = mappingNodes(part) |
| 210 | annotationsPart = newYamlMap(key, part, offset) |
| 211 | lines.Last = max(lines.Last, annotationsPart.Lines.Last) |
| 212 | default: |
| 213 | unknownKeys = append(unknownKeys, key) |
| 214 | } |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | if exprPart != nil && exprPart.Value.Lines.First != exprPart.Value.Lines.Last { |
| 219 | contentLines := strings.Split(string(content), "\n") |
| 220 | for { |
| 221 | start := exprPart.Value.Lines.First |
| 222 | end := exprPart.Value.Lines.Last |
| 223 | if end > len(contentLines) { |
| 224 | end-- |
| 225 | } |
| 226 | input := strings.Join(contentLines[start:end], "") |
| 227 | input = strings.ReplaceAll(input, " ", "") |
| 228 | output := strings.ReplaceAll(exprPart.Value.Value, "\n", "") |
| 229 | output = strings.ReplaceAll(output, " ", "") |
| 230 | if end >= len(contentLines) { |
| 231 | break |
| 232 | } |
| 233 | if input == output { |
| 234 | break |
| 235 | } |
| 236 | exprPart.Value.Lines.Last = end + 1 |
| 237 | } |
| 238 | } |
| 239 | |
| 240 | if recordPart != nil && alertPart != nil { |
| 241 | rule = Rule{ |
| 242 | Lines: lines, |
| 243 | Error: ParseError{ |
| 244 | Line: node.Line + offset, |
| 245 | Err: fmt.Errorf("got both %s and %s keys in a single rule", recordKey, alertKey), |
| 246 | }, |
| 247 | } |
| 248 | return rule, false |
| 249 | } |
| 250 | if exprPart != nil && alertPart == nil && recordPart == nil { |
| 251 | rule = Rule{ |
| 252 | Lines: lines, |
| 253 | Error: ParseError{ |
| 254 | Line: exprPart.Value.Lines.Last, |
| 255 | Err: fmt.Errorf("incomplete rule, no %s or %s key", alertKey, recordKey), |
| 256 | }, |
| 257 | } |
| 258 | return rule, false |
| 259 | } |
| 260 | if recordPart != nil && forPart != nil { |
| 261 | rule = Rule{ |
| 262 | Lines: lines, |
| 263 | Error: ParseError{ |
| 264 | Line: forPart.Lines.First, |
| 265 | Err: fmt.Errorf("invalid field '%s' in recording rule", forKey), |
| 266 | }, |
| 267 | } |
| 268 | return rule, false |
| 269 | } |
| 270 | if recordPart != nil && keepFiringForPart != nil { |
| 271 | rule = Rule{ |
| 272 | Lines: lines, |
| 273 | Error: ParseError{ |
| 274 | Line: keepFiringForPart.Lines.First, |
| 275 | Err: fmt.Errorf("invalid field '%s' in recording rule", keepFiringForKey), |
| 276 | }, |
| 277 | } |
| 278 | return rule, false |
| 279 | } |
| 280 | if recordPart != nil && annotationsPart != nil { |
| 281 | rule = Rule{ |
| 282 | Lines: lines, |
| 283 | Error: ParseError{ |
| 284 | Line: annotationsPart.Lines.First, |
| 285 | Err: fmt.Errorf("invalid field '%s' in recording rule", annotationsKey), |
| 286 | }, |
| 287 | } |
| 288 | return rule, false |
| 289 | } |
| 290 | for key, part := range map[string]*yaml.Node{ |
| 291 | recordKey: recordNode, |
| 292 | alertKey: alertNode, |
| 293 | exprKey: exprNode, |
| 294 | forKey: forNode, |
| 295 | keepFiringForKey: keepFiringForNode, |
| 296 | } { |
| 297 | if part != nil && !isTag(part.ShortTag(), "!!str") { |
| 298 | return invalidValueError(lines, part.Line+offset, key, "string", describeTag(part.ShortTag())) |
| 299 | } |
| 300 | } |
| 301 | |
| 302 | for key, part := range map[string]*yaml.Node{ |
| 303 | labelsKey: labelsNode, |
| 304 | annotationsKey: annotationsNode, |
| 305 | } { |
| 306 | if part != nil && !isTag(part.ShortTag(), "!!map") { |
| 307 | return invalidValueError(lines, part.Line+offset, key, "mapping", describeTag(part.ShortTag())) |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | for section, parts := range map[string]map[*yaml.Node]*yaml.Node{ |
| 312 | labelsKey: labelsNodes, |
| 313 | annotationsKey: annotationsNodes, |
| 314 | } { |
| 315 | for key, value := range parts { |
| 316 | if !isTag(value.ShortTag(), "!!str") { |
| 317 | return invalidValueError(lines, value.Line+offset, fmt.Sprintf("%s %s", section, nodeValue(key)), "string", describeTag(value.ShortTag())) |
| 318 | } |
| 319 | } |
| 320 | } |
| 321 | |
| 322 | if r, ok := ensureRequiredKeys(lines, recordKey, recordPart, exprPart); !ok { |
| 323 | return r, false |
| 324 | } |
| 325 | if r, ok := ensureRequiredKeys(lines, alertKey, alertPart, exprPart); !ok { |
| 326 | return r, false |
| 327 | } |
| 328 | if (recordPart != nil || alertPart != nil) && len(unknownKeys) > 0 { |
| 329 | var keys []string |
| 330 | for _, n := range unknownKeys { |
| 331 | keys = append(keys, n.Value) |
| 332 | } |
| 333 | rule = Rule{ |
| 334 | Lines: lines, |
| 335 | Error: ParseError{ |
| 336 | Line: unknownKeys[0].Line + offset, |
| 337 | Err: fmt.Errorf("invalid key(s) found: %s", strings.Join(keys, ", ")), |
| 338 | }, |
| 339 | } |
| 340 | return rule, false |
| 341 | } |
| 342 | |
| 343 | if recordPart != nil && !model.IsValidMetricName(model.LabelValue(recordPart.Value)) { |
| 344 | return Rule{ |
| 345 | Lines: lines, |
| 346 | Error: ParseError{ |
| 347 | Line: recordPart.Lines.First, |
| 348 | Err: fmt.Errorf("invalid recording rule name: %s", recordPart.Value), |
| 349 | }, |
| 350 | }, false |
| 351 | } |
| 352 | |
| 353 | if (recordPart != nil || alertPart != nil) && labelsPart != nil { |
| 354 | for _, lab := range labelsPart.Items { |
| 355 | if !model.LabelName(lab.Key.Value).IsValid() || lab.Key.Value == model.MetricNameLabel { |
| 356 | return Rule{ |
| 357 | Lines: lines, |
| 358 | Error: ParseError{ |
| 359 | Line: lab.Key.Lines.First, |
| 360 | Err: fmt.Errorf("invalid label name: %s", lab.Key.Value), |
| 361 | }, |
| 362 | }, false |
| 363 | } |
| 364 | if !model.LabelValue(lab.Value.Value).IsValid() { |
| 365 | return Rule{ |
| 366 | Lines: lines, |
| 367 | Error: ParseError{ |
| 368 | Line: lab.Key.Lines.First, |
| 369 | Err: fmt.Errorf("invalid label value: %s", lab.Value.Value), |
| 370 | }, |
| 371 | }, false |
| 372 | } |
| 373 | } |
| 374 | } |
| 375 | |
| 376 | if alertPart != nil && annotationsPart != nil { |
| 377 | for _, ann := range annotationsPart.Items { |
| 378 | if !model.LabelName(ann.Key.Value).IsValid() { |
| 379 | return Rule{ |
| 380 | Lines: lines, |
| 381 | Error: ParseError{ |
| 382 | Line: ann.Key.Lines.First, |
| 383 | Err: fmt.Errorf("invalid annotation name: %s", ann.Key.Value), |
| 384 | }, |
| 385 | }, false |
| 386 | } |
| 387 | } |
| 388 | } |
| 389 | |
| 390 | if recordPart != nil && exprPart != nil { |
| 391 | rule = Rule{ |
| 392 | Lines: lines, |
| 393 | RecordingRule: &RecordingRule{ |
| 394 | Record: *recordPart, |
| 395 | Expr: *exprPart, |
| 396 | Labels: labelsPart, |
| 397 | }, |
| 398 | Comments: ruleComments, |
| 399 | } |
| 400 | return rule, false |
| 401 | } |
| 402 | |
| 403 | if alertPart != nil && exprPart != nil { |
| 404 | rule = Rule{ |
| 405 | Lines: lines, |
| 406 | AlertingRule: &AlertingRule{ |
| 407 | Alert: *alertPart, |
| 408 | Expr: *exprPart, |
| 409 | For: forPart, |
| 410 | KeepFiringFor: keepFiringForPart, |
| 411 | Labels: labelsPart, |
| 412 | Annotations: annotationsPart, |
| 413 | }, |
| 414 | Comments: ruleComments, |
| 415 | } |
| 416 | return rule, false |
| 417 | } |
| 418 | |
| 419 | return rule, true |
| 420 | } |
| 421 | |
| 422 | func unpackNodes(node *yaml.Node) []*yaml.Node { |
| 423 | nodes := make([]*yaml.Node, 0, len(node.Content)) |
| 424 | var isMerge bool |
| 425 | for _, part := range node.Content { |
| 426 | if part.ShortTag() == "!!merge" && part.Value == "<<" { |
| 427 | isMerge = true |
| 428 | } |
| 429 | |
| 430 | if part.Alias != nil { |
| 431 | if isMerge { |
| 432 | nodes = append(nodes, resolveMapAlias(part, node).Content...) |
| 433 | } else { |
| 434 | nodes = append(nodes, resolveMapAlias(part, part)) |
| 435 | } |
| 436 | isMerge = false |
| 437 | continue |
| 438 | } |
| 439 | if isMerge { |
| 440 | continue |
| 441 | } |
| 442 | nodes = append(nodes, part) |
| 443 | } |
| 444 | return nodes |
| 445 | } |
| 446 | |
| 447 | func nodeKeys(node *yaml.Node) (keys []string) { |
| 448 | if node.Kind != yaml.MappingNode { |
| 449 | return keys |
| 450 | } |
| 451 | for i, n := range node.Content { |
| 452 | if i%2 == 0 && n.Value != "" { |
| 453 | keys = append(keys, n.Value) |
| 454 | } |
| 455 | } |
| 456 | return keys |
| 457 | } |
| 458 | |
| 459 | func hasKey(node *yaml.Node, key string) bool { |
| 460 | for _, k := range nodeKeys(node) { |
| 461 | if k == key { |
| 462 | return true |
| 463 | } |
| 464 | } |
| 465 | return false |
| 466 | } |
| 467 | |
| 468 | func hasValue(node *YamlNode) bool { |
| 469 | if node == nil { |
| 470 | return false |
| 471 | } |
| 472 | return node.Value != "" |
| 473 | } |
| 474 | |
| 475 | func ensureRequiredKeys(lines LineRange, key string, keyVal *YamlNode, expr *PromQLExpr) (Rule, bool) { |
| 476 | if keyVal == nil { |
| 477 | return Rule{Lines: lines}, true |
| 478 | } |
| 479 | if !hasValue(keyVal) { |
| 480 | return Rule{ |
| 481 | Lines: lines, |
| 482 | Error: ParseError{ |
| 483 | Line: keyVal.Lines.Last, |
| 484 | Err: fmt.Errorf("%s value cannot be empty", key), |
| 485 | }, |
| 486 | }, false |
| 487 | } |
| 488 | if expr == nil { |
| 489 | return Rule{ |
| 490 | Lines: lines, |
| 491 | Error: ParseError{ |
| 492 | Line: keyVal.Lines.Last, |
| 493 | Err: fmt.Errorf("missing %s key", exprKey), |
| 494 | }, |
| 495 | }, false |
| 496 | } |
| 497 | if !hasValue(expr.Value) { |
| 498 | return Rule{ |
| 499 | Lines: lines, |
| 500 | Error: ParseError{ |
| 501 | Line: expr.Value.Lines.Last, |
| 502 | Err: fmt.Errorf("%s value cannot be empty", exprKey), |
| 503 | }, |
| 504 | }, false |
| 505 | } |
| 506 | return Rule{Lines: lines}, true |
| 507 | } |
| 508 | |
| 509 | func resolveMapAlias(part, parent *yaml.Node) *yaml.Node { |
| 510 | node := *part |
| 511 | node.Content = nil |
| 512 | var ok bool |
| 513 | for i, alias := range part.Alias.Content { |
| 514 | if i%2 == 0 { |
| 515 | ok = !hasKey(parent, alias.Value) |
| 516 | } |
| 517 | if ok { |
| 518 | node.Content = append(node.Content, alias) |
| 519 | } |
| 520 | if i%2 == 1 { |
| 521 | ok = false |
| 522 | } |
| 523 | } |
| 524 | return &node |
| 525 | } |
| 526 | |
| 527 | func duplicatedKeyError(lines LineRange, line int, key string) (Rule, bool) { |
| 528 | rule := Rule{ |
| 529 | Lines: lines, |
| 530 | Error: ParseError{ |
| 531 | Line: line, |
| 532 | Err: fmt.Errorf("duplicated %s key", key), |
| 533 | }, |
| 534 | } |
| 535 | return rule, false |
| 536 | } |
| 537 | |
| 538 | func invalidValueError(lines LineRange, line int, key, expectedKind, gotKind string) (Rule, bool) { |
| 539 | rule := Rule{ |
| 540 | Lines: lines, |
| 541 | Error: ParseError{ |
| 542 | Line: line, |
| 543 | Err: fmt.Errorf("%s value must be a YAML %s, got %s instead", key, expectedKind, gotKind), |
| 544 | }, |
| 545 | } |
| 546 | return rule, false |
| 547 | } |
| 548 | |
| 549 | func isTag(tag, expected string) bool { |
| 550 | if tag == "!!null" { |
| 551 | return true |
| 552 | } |
| 553 | return tag == expected |
| 554 | } |
| 555 | |
| 556 | func describeTag(tag string) string { |
| 557 | switch tag { |
| 558 | case "": |
| 559 | return "unknown type" |
| 560 | case "!!str": |
| 561 | return "string" |
| 562 | case "!!int": |
| 563 | return "integer" |
| 564 | case "!!seq": |
| 565 | return "list" |
| 566 | case "!!map": |
| 567 | return "mapping" |
| 568 | case "!!binary": |
| 569 | return "binary data" |
| 570 | default: |
| 571 | return strings.TrimLeft(tag, "!") |
| 572 | } |
| 573 | } |
| 574 | |
| 575 | func mappingNodes(node *yaml.Node) map[*yaml.Node]*yaml.Node { |
| 576 | m := make(map[*yaml.Node]*yaml.Node, len(node.Content)) |
| 577 | var key *yaml.Node |
| 578 | for _, child := range node.Content { |
| 579 | if key != nil { |
| 580 | m[key] = child |
| 581 | key = nil |
| 582 | } else { |
| 583 | key = child |
| 584 | } |
| 585 | } |
| 586 | return m |
| 587 | } |
| 588 | |