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FormatJson.php
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1 <?php
24 
28 class FormatJson {
36  public const UTF8_OK = 1;
37 
48  public const XMLMETA_OK = 2;
49 
57  public const ALL_OK = self::UTF8_OK | self::XMLMETA_OK;
58 
65  public const FORCE_ASSOC = 0x100;
66 
72  public const TRY_FIXING = 0x200;
73 
79  public const STRIP_COMMENTS = 0x400;
80 
98  public static function encode( $value, $pretty = false, $escaping = 0 ) {
99  // PHP escapes '/' to prevent breaking out of inline script blocks using '</script>',
100  // which is hardly useful when '<' and '>' are escaped (and inadequate), and such
101  // escaping negatively impacts the human readability of URLs and similar strings.
102  $options = JSON_UNESCAPED_SLASHES;
103  if ( $pretty || is_string( $pretty ) ) {
104  $options |= JSON_PRETTY_PRINT;
105  }
106  if ( $escaping & self::UTF8_OK ) {
107  $options |= JSON_UNESCAPED_UNICODE;
108  }
109  if ( !( $escaping & self::XMLMETA_OK ) ) {
110  $options |= JSON_HEX_TAG | JSON_HEX_AMP;
111  }
112  $json = json_encode( $value, $options );
113 
114  if ( is_string( $pretty ) && $pretty !== ' ' && $json !== false ) {
115  // Change the four-space indent to the provided indent.
116  // The regex matches four spaces either at the start of a line or immediately
117  // after the previous match. $pretty should contain only whitespace characters,
118  // so there should be no need to call StringUtils::escapeRegexReplacement().
119  $json = preg_replace( '/ {4}|.*+\n\K {4}/A', $pretty, $json );
120  }
121 
122  return $json;
123  }
124 
148  public static function decode( $value, $assoc = false ) {
149  return json_decode( $value, $assoc );
150  }
151 
162  public static function parse( $value, $options = 0 ) {
163  if ( $options & self::STRIP_COMMENTS ) {
164  $value = self::stripComments( $value );
165  }
166  $assoc = ( $options & self::FORCE_ASSOC ) !== 0;
167  $result = json_decode( $value, $assoc );
168  $code = json_last_error();
169 
170  if ( $code === JSON_ERROR_SYNTAX && ( $options & self::TRY_FIXING ) !== 0 ) {
171  // The most common error is the trailing comma in a list or an object.
172  // We cannot simply replace /,\s*[}\]]/ because it could be inside a string value.
173  // But we could use the fact that JSON does not allow multi-line string values,
174  // And remove trailing commas if they are et the end of a line.
175  // JSON only allows 4 control characters: [ \t\r\n]. So we must not use '\s' for matching.
176  // Regex match ,]<any non-quote chars>\n or ,\n] with optional spaces/tabs.
177  $count = 0;
178  $value =
179  preg_replace( '/,([ \t]*[}\]][^"\r\n]*([\r\n]|$)|[ \t]*[\r\n][ \t\r\n]*[}\]])/', '$1',
180  $value, -1, $count );
181  if ( $count > 0 ) {
182  $result = json_decode( $value, $assoc );
183  if ( json_last_error() === JSON_ERROR_NONE ) {
184  // Report warning
185  $st = Status::newGood( $result );
186  $st->warning( wfMessage( 'json-warn-trailing-comma' )->numParams( $count ) );
187  return $st;
188  }
189  }
190  }
191 
192  // JSON_ERROR_RECURSION, JSON_ERROR_INF_OR_NAN, JSON_ERROR_UNSUPPORTED_TYPE,
193  // are all encode errors that we don't need to care about here.
194  switch ( $code ) {
195  case JSON_ERROR_NONE:
196  return Status::newGood( $result );
197  default:
198  return Status::newFatal( wfMessage( 'json-error-unknown' )->numParams( $code ) );
199  case JSON_ERROR_DEPTH:
200  $msg = 'json-error-depth';
201  break;
202  case JSON_ERROR_STATE_MISMATCH:
203  $msg = 'json-error-state-mismatch';
204  break;
205  case JSON_ERROR_CTRL_CHAR:
206  $msg = 'json-error-ctrl-char';
207  break;
208  case JSON_ERROR_SYNTAX:
209  $msg = 'json-error-syntax';
210  break;
211  case JSON_ERROR_UTF8:
212  $msg = 'json-error-utf8';
213  break;
214  case JSON_ERROR_INVALID_PROPERTY_NAME:
215  $msg = 'json-error-invalid-property-name';
216  break;
217  case JSON_ERROR_UTF16:
218  $msg = 'json-error-utf16';
219  break;
220  }
221  return Status::newFatal( $msg );
222  }
223 
232  public static function stripComments( $json ) {
233  // Ensure we have a string
234  $str = (string)$json;
235  $buffer = '';
236  $maxLen = strlen( $str );
237  $mark = 0;
238 
239  $inString = false;
240  $inComment = false;
241  $multiline = false;
242 
243  for ( $idx = 0; $idx < $maxLen; $idx++ ) {
244  switch ( $str[$idx] ) {
245  case '"':
246  $lookBehind = ( $idx - 1 >= 0 ) ? $str[$idx - 1] : '';
247  if ( !$inComment && $lookBehind !== '\\' ) {
248  // Either started or ended a string
249  $inString = !$inString;
250  }
251  break;
252 
253  case '/':
254  $lookAhead = ( $idx + 1 < $maxLen ) ? $str[$idx + 1] : '';
255  $lookBehind = ( $idx - 1 >= 0 ) ? $str[$idx - 1] : '';
256  if ( $inString ) {
257  break;
258 
259  } elseif ( !$inComment &&
260  ( $lookAhead === '/' || $lookAhead === '*' )
261  ) {
262  // Transition into a comment
263  // Add characters seen to buffer
264  $buffer .= substr( $str, $mark, $idx - $mark );
265  // Consume the look ahead character
266  $idx++;
267  // Track state
268  $inComment = true;
269  $multiline = $lookAhead === '*';
270 
271  } elseif ( $multiline && $lookBehind === '*' ) {
272  // Found the end of the current comment
273  $mark = $idx + 1;
274  $inComment = false;
275  $multiline = false;
276  }
277  break;
278 
279  case "\n":
280  if ( $inComment && !$multiline ) {
281  // Found the end of the current comment
282  $mark = $idx + 1;
283  $inComment = false;
284  }
285  break;
286  }
287  }
288  if ( $inComment ) {
289  // Comment ends with input
290  // Technically we should check to ensure that we aren't in
291  // a multiline comment that hasn't been properly ended, but this
292  // is a strip filter, not a validating parser.
293  $mark = $maxLen;
294  }
295  // Add final chunk to buffer before returning
296  return $buffer . substr( $str, $mark, $maxLen - $mark );
297  }
298 }
wfMessage( $key,... $params)
This is the function for getting translated interface messages.
JSON formatter wrapper class.
Definition: FormatJson.php:28
const UTF8_OK
Skip escaping most characters above U+007F for readability and compactness.
Definition: FormatJson.php:36
static parse( $value, $options=0)
Decodes a JSON string.
Definition: FormatJson.php:162
const FORCE_ASSOC
If set, treat JSON objects '{...}' as associative arrays.
Definition: FormatJson.php:65
const TRY_FIXING
If set, attempt to fix invalid JSON.
Definition: FormatJson.php:72
static encode( $value, $pretty=false, $escaping=0)
Returns the JSON representation of a value.
Definition: FormatJson.php:98
const STRIP_COMMENTS
If set, strip comments from input before parsing as JSON.
Definition: FormatJson.php:79
static decode( $value, $assoc=false)
Decodes a JSON string.
Definition: FormatJson.php:148
const ALL_OK
Skip escaping as many characters as reasonably possible.
Definition: FormatJson.php:57
const XMLMETA_OK
Skip escaping the characters '<', '>', and '&', which have special meanings in HTML and XML.
Definition: FormatJson.php:48
static stripComments( $json)
Remove multiline and single line comments from an otherwise valid JSON input string.
Definition: FormatJson.php:232
Generic operation result class Has warning/error list, boolean status and arbitrary value.
Definition: Status.php:58