1// Copyright (C) MongoDB, Inc. 2017-present. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); you may 4// not use this file except in compliance with the License. You may obtain 5// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 6 7package bsonrw 8 9import ( 10 "bytes" 11 "encoding/base64" 12 "fmt" 13 "go.mongodb.org/mongo-driver/bson/primitive" 14 "io" 15 "math" 16 "sort" 17 "strconv" 18 "strings" 19 "sync" 20 "time" 21 "unicode/utf8" 22) 23 24var ejvwPool = sync.Pool{ 25 New: func() interface{} { 26 return new(extJSONValueWriter) 27 }, 28} 29 30// ExtJSONValueWriterPool is a pool for ExtJSON ValueWriters. 31type ExtJSONValueWriterPool struct { 32 pool sync.Pool 33} 34 35// NewExtJSONValueWriterPool creates a new pool for ValueWriter instances that write to ExtJSON. 36func NewExtJSONValueWriterPool() *ExtJSONValueWriterPool { 37 return &ExtJSONValueWriterPool{ 38 pool: sync.Pool{ 39 New: func() interface{} { 40 return new(extJSONValueWriter) 41 }, 42 }, 43 } 44} 45 46// Get retrieves a ExtJSON ValueWriter from the pool and resets it to use w as the destination. 47func (bvwp *ExtJSONValueWriterPool) Get(w io.Writer, canonical, escapeHTML bool) ValueWriter { 48 vw := bvwp.pool.Get().(*extJSONValueWriter) 49 if writer, ok := w.(*SliceWriter); ok { 50 vw.reset(*writer, canonical, escapeHTML) 51 vw.w = writer 52 return vw 53 } 54 vw.buf = vw.buf[:0] 55 vw.w = w 56 return vw 57} 58 59// Put inserts a ValueWriter into the pool. If the ValueWriter is not a ExtJSON ValueWriter, nothing 60// happens and ok will be false. 61func (bvwp *ExtJSONValueWriterPool) Put(vw ValueWriter) (ok bool) { 62 bvw, ok := vw.(*extJSONValueWriter) 63 if !ok { 64 return false 65 } 66 67 if _, ok := bvw.w.(*SliceWriter); ok { 68 bvw.buf = nil 69 } 70 bvw.w = nil 71 72 bvwp.pool.Put(bvw) 73 return true 74} 75 76type ejvwState struct { 77 mode mode 78} 79 80type extJSONValueWriter struct { 81 w io.Writer 82 buf []byte 83 84 stack []ejvwState 85 frame int64 86 canonical bool 87 escapeHTML bool 88} 89 90// NewExtJSONValueWriter creates a ValueWriter that writes Extended JSON to w. 91func NewExtJSONValueWriter(w io.Writer, canonical, escapeHTML bool) (ValueWriter, error) { 92 if w == nil { 93 return nil, errNilWriter 94 } 95 96 return newExtJSONWriter(w, canonical, escapeHTML), nil 97} 98 99func newExtJSONWriter(w io.Writer, canonical, escapeHTML bool) *extJSONValueWriter { 100 stack := make([]ejvwState, 1, 5) 101 stack[0] = ejvwState{mode: mTopLevel} 102 103 return &extJSONValueWriter{ 104 w: w, 105 buf: []byte{}, 106 stack: stack, 107 canonical: canonical, 108 escapeHTML: escapeHTML, 109 } 110} 111 112func newExtJSONWriterFromSlice(buf []byte, canonical, escapeHTML bool) *extJSONValueWriter { 113 stack := make([]ejvwState, 1, 5) 114 stack[0] = ejvwState{mode: mTopLevel} 115 116 return &extJSONValueWriter{ 117 buf: buf, 118 stack: stack, 119 canonical: canonical, 120 escapeHTML: escapeHTML, 121 } 122} 123 124func (ejvw *extJSONValueWriter) reset(buf []byte, canonical, escapeHTML bool) { 125 if ejvw.stack == nil { 126 ejvw.stack = make([]ejvwState, 1, 5) 127 } 128 129 ejvw.stack = ejvw.stack[:1] 130 ejvw.stack[0] = ejvwState{mode: mTopLevel} 131 ejvw.canonical = canonical 132 ejvw.escapeHTML = escapeHTML 133 ejvw.frame = 0 134 ejvw.buf = buf 135 ejvw.w = nil 136} 137 138func (ejvw *extJSONValueWriter) advanceFrame() { 139 if ejvw.frame+1 >= int64(len(ejvw.stack)) { // We need to grow the stack 140 length := len(ejvw.stack) 141 if length+1 >= cap(ejvw.stack) { 142 // double it 143 buf := make([]ejvwState, 2*cap(ejvw.stack)+1) 144 copy(buf, ejvw.stack) 145 ejvw.stack = buf 146 } 147 ejvw.stack = ejvw.stack[:length+1] 148 } 149 ejvw.frame++ 150} 151 152func (ejvw *extJSONValueWriter) push(m mode) { 153 ejvw.advanceFrame() 154 155 ejvw.stack[ejvw.frame].mode = m 156} 157 158func (ejvw *extJSONValueWriter) pop() { 159 switch ejvw.stack[ejvw.frame].mode { 160 case mElement, mValue: 161 ejvw.frame-- 162 case mDocument, mArray, mCodeWithScope: 163 ejvw.frame -= 2 // we pop twice to jump over the mElement: mDocument -> mElement -> mDocument/mTopLevel/etc... 164 } 165} 166 167func (ejvw *extJSONValueWriter) invalidTransitionErr(destination mode, name string, modes []mode) error { 168 te := TransitionError{ 169 name: name, 170 current: ejvw.stack[ejvw.frame].mode, 171 destination: destination, 172 modes: modes, 173 action: "write", 174 } 175 if ejvw.frame != 0 { 176 te.parent = ejvw.stack[ejvw.frame-1].mode 177 } 178 return te 179} 180 181func (ejvw *extJSONValueWriter) ensureElementValue(destination mode, callerName string, addmodes ...mode) error { 182 switch ejvw.stack[ejvw.frame].mode { 183 case mElement, mValue: 184 default: 185 modes := []mode{mElement, mValue} 186 if addmodes != nil { 187 modes = append(modes, addmodes...) 188 } 189 return ejvw.invalidTransitionErr(destination, callerName, modes) 190 } 191 192 return nil 193} 194 195func (ejvw *extJSONValueWriter) writeExtendedSingleValue(key string, value string, quotes bool) { 196 var s string 197 if quotes { 198 s = fmt.Sprintf(`{"$%s":"%s"}`, key, value) 199 } else { 200 s = fmt.Sprintf(`{"$%s":%s}`, key, value) 201 } 202 203 ejvw.buf = append(ejvw.buf, []byte(s)...) 204} 205 206func (ejvw *extJSONValueWriter) WriteArray() (ArrayWriter, error) { 207 if err := ejvw.ensureElementValue(mArray, "WriteArray"); err != nil { 208 return nil, err 209 } 210 211 ejvw.buf = append(ejvw.buf, '[') 212 213 ejvw.push(mArray) 214 return ejvw, nil 215} 216 217func (ejvw *extJSONValueWriter) WriteBinary(b []byte) error { 218 return ejvw.WriteBinaryWithSubtype(b, 0x00) 219} 220 221func (ejvw *extJSONValueWriter) WriteBinaryWithSubtype(b []byte, btype byte) error { 222 if err := ejvw.ensureElementValue(mode(0), "WriteBinaryWithSubtype"); err != nil { 223 return err 224 } 225 226 var buf bytes.Buffer 227 buf.WriteString(`{"$binary":{"base64":"`) 228 buf.WriteString(base64.StdEncoding.EncodeToString(b)) 229 buf.WriteString(fmt.Sprintf(`","subType":"%02x"}},`, btype)) 230 231 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 232 233 ejvw.pop() 234 return nil 235} 236 237func (ejvw *extJSONValueWriter) WriteBoolean(b bool) error { 238 if err := ejvw.ensureElementValue(mode(0), "WriteBoolean"); err != nil { 239 return err 240 } 241 242 ejvw.buf = append(ejvw.buf, []byte(strconv.FormatBool(b))...) 243 ejvw.buf = append(ejvw.buf, ',') 244 245 ejvw.pop() 246 return nil 247} 248 249func (ejvw *extJSONValueWriter) WriteCodeWithScope(code string) (DocumentWriter, error) { 250 if err := ejvw.ensureElementValue(mCodeWithScope, "WriteCodeWithScope"); err != nil { 251 return nil, err 252 } 253 254 var buf bytes.Buffer 255 buf.WriteString(`{"$code":`) 256 writeStringWithEscapes(code, &buf, ejvw.escapeHTML) 257 buf.WriteString(`,"$scope":{`) 258 259 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 260 261 ejvw.push(mCodeWithScope) 262 return ejvw, nil 263} 264 265func (ejvw *extJSONValueWriter) WriteDBPointer(ns string, oid primitive.ObjectID) error { 266 if err := ejvw.ensureElementValue(mode(0), "WriteDBPointer"); err != nil { 267 return err 268 } 269 270 var buf bytes.Buffer 271 buf.WriteString(`{"$dbPointer":{"$ref":"`) 272 buf.WriteString(ns) 273 buf.WriteString(`","$id":{"$oid":"`) 274 buf.WriteString(oid.Hex()) 275 buf.WriteString(`"}}},`) 276 277 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 278 279 ejvw.pop() 280 return nil 281} 282 283func (ejvw *extJSONValueWriter) WriteDateTime(dt int64) error { 284 if err := ejvw.ensureElementValue(mode(0), "WriteDateTime"); err != nil { 285 return err 286 } 287 288 t := time.Unix(dt/1e3, dt%1e3*1e6).UTC() 289 290 if ejvw.canonical || t.Year() < 1970 || t.Year() > 9999 { 291 s := fmt.Sprintf(`{"$numberLong":"%d"}`, dt) 292 ejvw.writeExtendedSingleValue("date", s, false) 293 } else { 294 ejvw.writeExtendedSingleValue("date", t.Format(rfc3339Milli), true) 295 } 296 297 ejvw.buf = append(ejvw.buf, ',') 298 299 ejvw.pop() 300 return nil 301} 302 303func (ejvw *extJSONValueWriter) WriteDecimal128(d primitive.Decimal128) error { 304 if err := ejvw.ensureElementValue(mode(0), "WriteDecimal128"); err != nil { 305 return err 306 } 307 308 ejvw.writeExtendedSingleValue("numberDecimal", d.String(), true) 309 ejvw.buf = append(ejvw.buf, ',') 310 311 ejvw.pop() 312 return nil 313} 314 315func (ejvw *extJSONValueWriter) WriteDocument() (DocumentWriter, error) { 316 if ejvw.stack[ejvw.frame].mode == mTopLevel { 317 ejvw.buf = append(ejvw.buf, '{') 318 return ejvw, nil 319 } 320 321 if err := ejvw.ensureElementValue(mDocument, "WriteDocument", mTopLevel); err != nil { 322 return nil, err 323 } 324 325 ejvw.buf = append(ejvw.buf, '{') 326 ejvw.push(mDocument) 327 return ejvw, nil 328} 329 330func (ejvw *extJSONValueWriter) WriteDouble(f float64) error { 331 if err := ejvw.ensureElementValue(mode(0), "WriteDouble"); err != nil { 332 return err 333 } 334 335 s := formatDouble(f) 336 337 if ejvw.canonical { 338 ejvw.writeExtendedSingleValue("numberDouble", s, true) 339 } else { 340 switch s { 341 case "Infinity": 342 fallthrough 343 case "-Infinity": 344 fallthrough 345 case "NaN": 346 s = fmt.Sprintf(`{"$numberDouble":"%s"}`, s) 347 } 348 ejvw.buf = append(ejvw.buf, []byte(s)...) 349 } 350 351 ejvw.buf = append(ejvw.buf, ',') 352 353 ejvw.pop() 354 return nil 355} 356 357func (ejvw *extJSONValueWriter) WriteInt32(i int32) error { 358 if err := ejvw.ensureElementValue(mode(0), "WriteInt32"); err != nil { 359 return err 360 } 361 362 s := strconv.FormatInt(int64(i), 10) 363 364 if ejvw.canonical { 365 ejvw.writeExtendedSingleValue("numberInt", s, true) 366 } else { 367 ejvw.buf = append(ejvw.buf, []byte(s)...) 368 } 369 370 ejvw.buf = append(ejvw.buf, ',') 371 372 ejvw.pop() 373 return nil 374} 375 376func (ejvw *extJSONValueWriter) WriteInt64(i int64) error { 377 if err := ejvw.ensureElementValue(mode(0), "WriteInt64"); err != nil { 378 return err 379 } 380 381 s := strconv.FormatInt(i, 10) 382 383 if ejvw.canonical { 384 ejvw.writeExtendedSingleValue("numberLong", s, true) 385 } else { 386 ejvw.buf = append(ejvw.buf, []byte(s)...) 387 } 388 389 ejvw.buf = append(ejvw.buf, ',') 390 391 ejvw.pop() 392 return nil 393} 394 395func (ejvw *extJSONValueWriter) WriteJavascript(code string) error { 396 if err := ejvw.ensureElementValue(mode(0), "WriteJavascript"); err != nil { 397 return err 398 } 399 400 var buf bytes.Buffer 401 writeStringWithEscapes(code, &buf, ejvw.escapeHTML) 402 403 ejvw.writeExtendedSingleValue("code", buf.String(), false) 404 ejvw.buf = append(ejvw.buf, ',') 405 406 ejvw.pop() 407 return nil 408} 409 410func (ejvw *extJSONValueWriter) WriteMaxKey() error { 411 if err := ejvw.ensureElementValue(mode(0), "WriteMaxKey"); err != nil { 412 return err 413 } 414 415 ejvw.writeExtendedSingleValue("maxKey", "1", false) 416 ejvw.buf = append(ejvw.buf, ',') 417 418 ejvw.pop() 419 return nil 420} 421 422func (ejvw *extJSONValueWriter) WriteMinKey() error { 423 if err := ejvw.ensureElementValue(mode(0), "WriteMinKey"); err != nil { 424 return err 425 } 426 427 ejvw.writeExtendedSingleValue("minKey", "1", false) 428 ejvw.buf = append(ejvw.buf, ',') 429 430 ejvw.pop() 431 return nil 432} 433 434func (ejvw *extJSONValueWriter) WriteNull() error { 435 if err := ejvw.ensureElementValue(mode(0), "WriteNull"); err != nil { 436 return err 437 } 438 439 ejvw.buf = append(ejvw.buf, []byte("null")...) 440 ejvw.buf = append(ejvw.buf, ',') 441 442 ejvw.pop() 443 return nil 444} 445 446func (ejvw *extJSONValueWriter) WriteObjectID(oid primitive.ObjectID) error { 447 if err := ejvw.ensureElementValue(mode(0), "WriteObjectID"); err != nil { 448 return err 449 } 450 451 ejvw.writeExtendedSingleValue("oid", oid.Hex(), true) 452 ejvw.buf = append(ejvw.buf, ',') 453 454 ejvw.pop() 455 return nil 456} 457 458func (ejvw *extJSONValueWriter) WriteRegex(pattern string, options string) error { 459 if err := ejvw.ensureElementValue(mode(0), "WriteRegex"); err != nil { 460 return err 461 } 462 463 var buf bytes.Buffer 464 buf.WriteString(`{"$regularExpression":{"pattern":`) 465 writeStringWithEscapes(pattern, &buf, ejvw.escapeHTML) 466 buf.WriteString(`,"options":"`) 467 buf.WriteString(sortStringAlphebeticAscending(options)) 468 buf.WriteString(`"}},`) 469 470 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 471 472 ejvw.pop() 473 return nil 474} 475 476func (ejvw *extJSONValueWriter) WriteString(s string) error { 477 if err := ejvw.ensureElementValue(mode(0), "WriteString"); err != nil { 478 return err 479 } 480 481 var buf bytes.Buffer 482 writeStringWithEscapes(s, &buf, ejvw.escapeHTML) 483 484 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 485 ejvw.buf = append(ejvw.buf, ',') 486 487 ejvw.pop() 488 return nil 489} 490 491func (ejvw *extJSONValueWriter) WriteSymbol(symbol string) error { 492 if err := ejvw.ensureElementValue(mode(0), "WriteSymbol"); err != nil { 493 return err 494 } 495 496 var buf bytes.Buffer 497 writeStringWithEscapes(symbol, &buf, ejvw.escapeHTML) 498 499 ejvw.writeExtendedSingleValue("symbol", buf.String(), false) 500 ejvw.buf = append(ejvw.buf, ',') 501 502 ejvw.pop() 503 return nil 504} 505 506func (ejvw *extJSONValueWriter) WriteTimestamp(t uint32, i uint32) error { 507 if err := ejvw.ensureElementValue(mode(0), "WriteTimestamp"); err != nil { 508 return err 509 } 510 511 var buf bytes.Buffer 512 buf.WriteString(`{"$timestamp":{"t":`) 513 buf.WriteString(strconv.FormatUint(uint64(t), 10)) 514 buf.WriteString(`,"i":`) 515 buf.WriteString(strconv.FormatUint(uint64(i), 10)) 516 buf.WriteString(`}},`) 517 518 ejvw.buf = append(ejvw.buf, buf.Bytes()...) 519 520 ejvw.pop() 521 return nil 522} 523 524func (ejvw *extJSONValueWriter) WriteUndefined() error { 525 if err := ejvw.ensureElementValue(mode(0), "WriteUndefined"); err != nil { 526 return err 527 } 528 529 ejvw.writeExtendedSingleValue("undefined", "true", false) 530 ejvw.buf = append(ejvw.buf, ',') 531 532 ejvw.pop() 533 return nil 534} 535 536func (ejvw *extJSONValueWriter) WriteDocumentElement(key string) (ValueWriter, error) { 537 switch ejvw.stack[ejvw.frame].mode { 538 case mDocument, mTopLevel, mCodeWithScope: 539 ejvw.buf = append(ejvw.buf, []byte(fmt.Sprintf(`"%s":`, key))...) 540 ejvw.push(mElement) 541 default: 542 return nil, ejvw.invalidTransitionErr(mElement, "WriteDocumentElement", []mode{mDocument, mTopLevel, mCodeWithScope}) 543 } 544 545 return ejvw, nil 546} 547 548func (ejvw *extJSONValueWriter) WriteDocumentEnd() error { 549 switch ejvw.stack[ejvw.frame].mode { 550 case mDocument, mTopLevel, mCodeWithScope: 551 default: 552 return fmt.Errorf("incorrect mode to end document: %s", ejvw.stack[ejvw.frame].mode) 553 } 554 555 // close the document 556 if ejvw.buf[len(ejvw.buf)-1] == ',' { 557 ejvw.buf[len(ejvw.buf)-1] = '}' 558 } else { 559 ejvw.buf = append(ejvw.buf, '}') 560 } 561 562 switch ejvw.stack[ejvw.frame].mode { 563 case mCodeWithScope: 564 ejvw.buf = append(ejvw.buf, '}') 565 fallthrough 566 case mDocument: 567 ejvw.buf = append(ejvw.buf, ',') 568 case mTopLevel: 569 if ejvw.w != nil { 570 if _, err := ejvw.w.Write(ejvw.buf); err != nil { 571 return err 572 } 573 ejvw.buf = ejvw.buf[:0] 574 } 575 } 576 577 ejvw.pop() 578 return nil 579} 580 581func (ejvw *extJSONValueWriter) WriteArrayElement() (ValueWriter, error) { 582 switch ejvw.stack[ejvw.frame].mode { 583 case mArray: 584 ejvw.push(mValue) 585 default: 586 return nil, ejvw.invalidTransitionErr(mValue, "WriteArrayElement", []mode{mArray}) 587 } 588 589 return ejvw, nil 590} 591 592func (ejvw *extJSONValueWriter) WriteArrayEnd() error { 593 switch ejvw.stack[ejvw.frame].mode { 594 case mArray: 595 // close the array 596 if ejvw.buf[len(ejvw.buf)-1] == ',' { 597 ejvw.buf[len(ejvw.buf)-1] = ']' 598 } else { 599 ejvw.buf = append(ejvw.buf, ']') 600 } 601 602 ejvw.buf = append(ejvw.buf, ',') 603 604 ejvw.pop() 605 default: 606 return fmt.Errorf("incorrect mode to end array: %s", ejvw.stack[ejvw.frame].mode) 607 } 608 609 return nil 610} 611 612func formatDouble(f float64) string { 613 var s string 614 if math.IsInf(f, 1) { 615 s = "Infinity" 616 } else if math.IsInf(f, -1) { 617 s = "-Infinity" 618 } else if math.IsNaN(f) { 619 s = "NaN" 620 } else { 621 // Print exactly one decimalType place for integers; otherwise, print as many are necessary to 622 // perfectly represent it. 623 s = strconv.FormatFloat(f, 'G', -1, 64) 624 if !strings.ContainsRune(s, 'E') && !strings.ContainsRune(s, '.') { 625 s += ".0" 626 } 627 } 628 629 return s 630} 631 632var hexChars = "0123456789abcdef" 633 634func writeStringWithEscapes(s string, buf *bytes.Buffer, escapeHTML bool) { 635 buf.WriteByte('"') 636 start := 0 637 for i := 0; i < len(s); { 638 if b := s[i]; b < utf8.RuneSelf { 639 if htmlSafeSet[b] || (!escapeHTML && safeSet[b]) { 640 i++ 641 continue 642 } 643 if start < i { 644 buf.WriteString(s[start:i]) 645 } 646 switch b { 647 case '\\', '"': 648 buf.WriteByte('\\') 649 buf.WriteByte(b) 650 case '\n': 651 buf.WriteByte('\\') 652 buf.WriteByte('n') 653 case '\r': 654 buf.WriteByte('\\') 655 buf.WriteByte('r') 656 case '\t': 657 buf.WriteByte('\\') 658 buf.WriteByte('t') 659 case '\b': 660 buf.WriteByte('\\') 661 buf.WriteByte('b') 662 case '\f': 663 buf.WriteByte('\\') 664 buf.WriteByte('f') 665 default: 666 // This encodes bytes < 0x20 except for \t, \n and \r. 667 // If escapeHTML is set, it also escapes <, >, and & 668 // because they can lead to security holes when 669 // user-controlled strings are rendered into JSON 670 // and served to some browsers. 671 buf.WriteString(`\u00`) 672 buf.WriteByte(hexChars[b>>4]) 673 buf.WriteByte(hexChars[b&0xF]) 674 } 675 i++ 676 start = i 677 continue 678 } 679 c, size := utf8.DecodeRuneInString(s[i:]) 680 if c == utf8.RuneError && size == 1 { 681 if start < i { 682 buf.WriteString(s[start:i]) 683 } 684 buf.WriteString(`\ufffd`) 685 i += size 686 start = i 687 continue 688 } 689 // U+2028 is LINE SEPARATOR. 690 // U+2029 is PARAGRAPH SEPARATOR. 691 // They are both technically valid characters in JSON strings, 692 // but don't work in JSONP, which has to be evaluated as JavaScript, 693 // and can lead to security holes there. It is valid JSON to 694 // escape them, so we do so unconditionally. 695 // See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion. 696 if c == '\u2028' || c == '\u2029' { 697 if start < i { 698 buf.WriteString(s[start:i]) 699 } 700 buf.WriteString(`\u202`) 701 buf.WriteByte(hexChars[c&0xF]) 702 i += size 703 start = i 704 continue 705 } 706 i += size 707 } 708 if start < len(s) { 709 buf.WriteString(s[start:]) 710 } 711 buf.WriteByte('"') 712} 713 714type sortableString []rune 715 716func (ss sortableString) Len() int { 717 return len(ss) 718} 719 720func (ss sortableString) Less(i, j int) bool { 721 return ss[i] < ss[j] 722} 723 724func (ss sortableString) Swap(i, j int) { 725 oldI := ss[i] 726 ss[i] = ss[j] 727 ss[j] = oldI 728} 729 730func sortStringAlphebeticAscending(s string) string { 731 ss := sortableString([]rune(s)) 732 sort.Sort(ss) 733 return string([]rune(ss)) 734} 735