Lady’s Gitweb - Gitweb/blob - static/js/blame_incremental.js

   1 // Copyright (C) 2007, Fredrik Kuivinen <frekui@gmail.com>
   2 //               2007, Petr Baudis <pasky@suse.cz>
   3 //          2008-2011, Jakub Narebski <jnareb@gmail.com>
   4
   5 /**
   6  * @fileOverview JavaScript side of Ajax-y 'blame_incremental' view in gitweb
   7  * @license GPLv2 or later
   8  */
   9
  10 /* ============================================================ */
  11 /*
  12  * This code uses DOM methods instead of (nonstandard) innerHTML
  13  * to modify page.
  14  *
  15  * innerHTML is non-standard IE extension, though supported by most
  16  * browsers; however Firefox up to version 1.5 didn't implement it in
  17  * a strict mode (application/xml+xhtml mimetype).
  18  *
  19  * Also my simple benchmarks show that using elem.firstChild.data =
  20  * 'content' is slightly faster than elem.innerHTML = 'content'.  It
  21  * is however more fragile (text element fragment must exists), and
  22  * less feature-rich (we cannot add HTML).
  23  *
  24  * Note that DOM 2 HTML is preferred over generic DOM 2 Core; the
  25  * equivalent using DOM 2 Core is usually shown in comments.
  26  */
  27
  28
  29 /* ............................................................ */
  30 /* utility/helper functions (and variables) */
  31
  32 var xhr;        // XMLHttpRequest object
  33 var projectUrl; // partial query + separator ('?' or ';')
  34
  35 // 'commits' is an associative map. It maps SHA1s to Commit objects.
  36 var commits = {};
  37
  38 /**
  39  * constructor for Commit objects, used in 'blame'
  40  * @class Represents a blamed commit
  41  * @param {String} sha1: SHA-1 identifier of a commit
  42  */
  43 function Commit(sha1) {
  44         if (this instanceof Commit) {
  45                 this.sha1 = sha1;
  46                 this.nprevious = 0; /* number of 'previous', effective parents */
  47         } else {
  48                 return new Commit(sha1);
  49         }
  50 }
  51
  52 /* ............................................................ */
  53 /* progress info, timing, error reporting */
  54
  55 var blamedLines = 0;
  56 var totalLines  = '???';
  57 var div_progress_bar;
  58 var div_progress_info;
  59
  60 /**
  61  * Detects how many lines does a blamed file have,
  62  * This information is used in progress info
  63  *
  64  * @returns {Number|String} Number of lines in file, or string '...'
  65  */
  66 function countLines() {
  67         var table =
  68                 document.getElementById('blame_table') ||
  69                 document.getElementsByTagName('table')[0];
  70
  71         if (table) {
  72                 return table.getElementsByTagName('tr').length - 1; // for header
  73         } else {
  74                 return '...';
  75         }
  76 }
  77
  78 /**
  79  * update progress info and length (width) of progress bar
  80  *
  81  * @globals div_progress_info, div_progress_bar, blamedLines, totalLines
  82  */
  83 function updateProgressInfo() {
  84         if (!div_progress_info) {
  85                 div_progress_info = document.getElementById('progress_info');
  86         }
  87         if (!div_progress_bar) {
  88                 div_progress_bar = document.getElementById('progress_bar');
  89         }
  90         if (!div_progress_info && !div_progress_bar) {
  91                 return;
  92         }
  93
  94         var percentage = Math.floor(100.0*blamedLines/totalLines);
  95
  96         if (div_progress_info) {
  97                 div_progress_info.firstChild.data  = blamedLines + ' / ' + totalLines +
  98                         ' (' + padLeftStr(percentage, 3, '\u00A0') + '%)';
  99         }
 100
 101         if (div_progress_bar) {
 102                 //div_progress_bar.setAttribute('style', 'width: '+percentage+'%;');
 103                 div_progress_bar.style.width = percentage + '%';
 104         }
 105 }
 106
 107
 108 var t_interval_server = '';
 109 var cmds_server = '';
 110 var t0 = new Date();
 111
 112 /**
 113  * write how much it took to generate data, and to run script
 114  *
 115  * @globals t0, t_interval_server, cmds_server
 116  */
 117 function writeTimeInterval() {
 118         var info_time = document.getElementById('generating_time');
 119         if (!info_time || !t_interval_server) {
 120                 return;
 121         }
 122         var t1 = new Date();
 123         info_time.firstChild.data += ' + (' +
 124                 t_interval_server + ' sec server blame_data / ' +
 125                 (t1.getTime() - t0.getTime())/1000 + ' sec client JavaScript)';
 126
 127         var info_cmds = document.getElementById('generating_cmd');
 128         if (!info_time || !cmds_server) {
 129                 return;
 130         }
 131         info_cmds.firstChild.data += ' + ' + cmds_server;
 132 }
 133
 134 /**
 135  * show an error message alert to user within page (in progress info area)
 136  * @param {String} str: plain text error message (no HTML)
 137  *
 138  * @globals div_progress_info
 139  */
 140 function errorInfo(str) {
 141         if (!div_progress_info) {
 142                 div_progress_info = document.getElementById('progress_info');
 143         }
 144         if (div_progress_info) {
 145                 div_progress_info.className = 'error';
 146                 div_progress_info.firstChild.data = str;
 147         }
 148 }
 149
 150 /* ............................................................ */
 151 /* coloring rows during blame_data (git blame --incremental) run */
 152
 153 /**
 154  * used to extract N from 'colorN', where N is a number,
 155  * @constant
 156  */
 157 var colorRe = /\bcolor([0-9]*)\b/;
 158
 159 /**
 160  * return N if <tr class="colorN">, otherwise return null
 161  * (some browsers require CSS class names to begin with letter)
 162  *
 163  * @param {HTMLElement} tr: table row element to check
 164  * @param {String} tr.className: 'class' attribute of tr element
 165  * @returns {Number|null} N if tr.className == 'colorN', otherwise null
 166  *
 167  * @globals colorRe
 168  */
 169 function getColorNo(tr) {
 170         if (!tr) {
 171                 return null;
 172         }
 173         var className = tr.className;
 174         if (className) {
 175                 var match = colorRe.exec(className);
 176                 if (match) {
 177                         return parseInt(match[1], 10);
 178                 }
 179         }
 180         return null;
 181 }
 182
 183 var colorsFreq = [0, 0, 0];
 184 /**
 185  * return one of given possible colors (currently least used one)
 186  * example: chooseColorNoFrom(2, 3) returns 2 or 3
 187  *
 188  * @param {Number[]} arguments: one or more numbers
 189  *        assumes that  1 <= arguments[i] <= colorsFreq.length
 190  * @returns {Number} Least used color number from arguments
 191  * @globals colorsFreq
 192  */
 193 function chooseColorNoFrom() {
 194         // choose the color which is least used
 195         var colorNo = arguments[0];
 196         for (var i = 1; i < arguments.length; i++) {
 197                 if (colorsFreq[arguments[i]-1] < colorsFreq[colorNo-1]) {
 198                         colorNo = arguments[i];
 199                 }
 200         }
 201         colorsFreq[colorNo-1]++;
 202         return colorNo;
 203 }
 204
 205 /**
 206  * given two neighbor <tr> elements, find color which would be different
 207  * from color of both of neighbors; used to 3-color blame table
 208  *
 209  * @param {HTMLElement} tr_prev
 210  * @param {HTMLElement} tr_next
 211  * @returns {Number} color number N such that
 212  * colorN != tr_prev.className && colorN != tr_next.className
 213  */
 214 function findColorNo(tr_prev, tr_next) {
 215         var color_prev = getColorNo(tr_prev);
 216         var color_next = getColorNo(tr_next);
 217
 218
 219         // neither of neighbors has color set
 220         // THEN we can use any of 3 possible colors
 221         if (!color_prev && !color_next) {
 222                 return chooseColorNoFrom(1,2,3);
 223         }
 224
 225         // either both neighbors have the same color,
 226         // or only one of neighbors have color set
 227         // THEN we can use any color except given
 228         var color;
 229         if (color_prev === color_next) {
 230                 color = color_prev; // = color_next;
 231         } else if (!color_prev) {
 232                 color = color_next;
 233         } else if (!color_next) {
 234                 color = color_prev;
 235         }
 236         if (color) {
 237                 return chooseColorNoFrom((color % 3) + 1, ((color+1) % 3) + 1);
 238         }
 239
 240         // neighbors have different colors
 241         // THEN there is only one color left
 242         return (3 - ((color_prev + color_next) % 3));
 243 }
 244
 245 /* ............................................................ */
 246 /* coloring rows like 'blame' after 'blame_data' finishes */
 247
 248 /**
 249  * returns true if given row element (tr) is first in commit group
 250  * to be used only after 'blame_data' finishes (after processing)
 251  *
 252  * @param {HTMLElement} tr: table row
 253  * @returns {Boolean} true if TR is first in commit group
 254  */
 255 function isStartOfGroup(tr) {
 256         return tr.firstChild.className === 'sha1';
 257 }
 258
 259 /**
 260  * change colors to use zebra coloring (2 colors) instead of 3 colors
 261  * concatenate neighbor commit groups belonging to the same commit
 262  *
 263  * @globals colorRe
 264  */
 265 function fixColorsAndGroups() {
 266         var colorClasses = ['light', 'dark'];
 267         var linenum = 1;
 268         var tr, prev_group;
 269         var colorClass = 0;
 270         var table =
 271                 document.getElementById('blame_table') ||
 272                 document.getElementsByTagName('table')[0];
 273
 274         while ((tr = document.getElementById('l'+linenum))) {
 275         // index origin is 0, which is table header; start from 1
 276         //while ((tr = table.rows[linenum])) { // <- it is slower
 277                 if (isStartOfGroup(tr, linenum, document)) {
 278                         if (prev_group &&
 279                             prev_group.firstChild.firstChild.href ===
 280                                     tr.firstChild.firstChild.href) {
 281                                 // we have to concatenate groups
 282                                 var prev_rows = prev_group.firstChild.rowSpan || 1;
 283                                 var curr_rows =         tr.firstChild.rowSpan || 1;
 284                                 prev_group.firstChild.rowSpan = prev_rows + curr_rows;
 285                                 //tr.removeChild(tr.firstChild);
 286                                 tr.deleteCell(0); // DOM2 HTML way
 287                         } else {
 288                                 colorClass = (colorClass + 1) % 2;
 289                                 prev_group = tr;
 290                         }
 291                 }
 292                 var tr_class = tr.className;
 293                 tr.className = tr_class.replace(colorRe, colorClasses[colorClass]);
 294                 linenum++;
 295         }
 296 }
 297
 298
 299 /* ============================================================ */
 300 /* main part: parsing response */
 301
 302 /**
 303  * Function called for each blame entry, as soon as it finishes.
 304  * It updates page via DOM manipulation, adding sha1 info, etc.
 305  *
 306  * @param {Commit} commit: blamed commit
 307  * @param {Object} group: object representing group of lines,
 308  *                        which blame the same commit (blame entry)
 309  *
 310  * @globals blamedLines
 311  */
 312 function handleLine(commit, group) {
 313         /*
 314            This is the structure of the HTML fragment we are working
 315            with:
 316
 317            <tr id="l123" class="">
 318              <td class="sha1" title=""><a href=""> </a></td>
 319              <td class="linenr"><a class="linenr" href="">123</a></td>
 320              <td class="pre"># times (my ext3 doesn&#39;t).</td>
 321            </tr>
 322         */
 323
 324         var resline = group.resline;
 325
 326         // format date and time string only once per commit
 327         if (!commit.info) {
 328                 /* e.g. 'Kay Sievers, 2005-08-07 21:49:46 +0200' */
 329                 commit.info = commit.author + ', ' +
 330                         formatDateISOLocal(commit.authorTime, commit.authorTimezone);
 331         }
 332
 333         // color depends on group of lines, not only on blamed commit
 334         var colorNo = findColorNo(
 335                 document.getElementById('l'+(resline-1)),
 336                 document.getElementById('l'+(resline+group.numlines))
 337         );
 338
 339         // loop over lines in commit group
 340         for (var i = 0; i < group.numlines; i++, resline++) {
 341                 var tr = document.getElementById('l'+resline);
 342                 if (!tr) {
 343                         break;
 344                 }
 345                 /*
 346                         <tr id="l123" class="">
 347                           <td class="sha1" title=""><a href=""> </a></td>
 348                           <td class="linenr"><a class="linenr" href="">123</a></td>
 349                           <td class="pre"># times (my ext3 doesn&#39;t).</td>
 350                         </tr>
 351                 */
 352                 var td_sha1  = tr.firstChild;
 353                 var a_sha1   = td_sha1.firstChild;
 354                 var a_linenr = td_sha1.nextSibling.firstChild;
 355
 356                 /* <tr id="l123" class=""> */
 357                 var tr_class = '';
 358                 if (colorNo !== null) {
 359                         tr_class = 'color'+colorNo;
 360                 }
 361                 if (commit.boundary) {
 362                         tr_class += ' boundary';
 363                 }
 364                 if (commit.nprevious === 0) {
 365                         tr_class += ' no-previous';
 366                 } else if (commit.nprevious > 1) {
 367                         tr_class += ' multiple-previous';
 368                 }
 369                 tr.className = tr_class;
 370
 371                 /* <td class="sha1" title="?" rowspan="?"><a href="?">?</a></td> */
 372                 if (i === 0) {
 373                         td_sha1.title = commit.info;
 374                         td_sha1.rowSpan = group.numlines;
 375
 376                         a_sha1.href = projectUrl + 'a=commit;h=' + commit.sha1;
 377                         if (a_sha1.firstChild) {
 378                                 a_sha1.firstChild.data = commit.sha1.substr(0, 8);
 379                         } else {
 380                                 a_sha1.appendChild(
 381                                         document.createTextNode(commit.sha1.substr(0, 8)));
 382                         }
 383                         if (group.numlines >= 2) {
 384                                 var fragment = document.createDocumentFragment();
 385                                 var br   = document.createElement("br");
 386                                 var match = commit.author.match(/\b([A-Z])\B/g);
 387                                 if (match) {
 388                                         var text = document.createTextNode(
 389                                                         match.join(''));
 390                                 }
 391                                 if (br && text) {
 392                                         var elem = fragment || td_sha1;
 393                                         elem.appendChild(br);
 394                                         elem.appendChild(text);
 395                                         if (fragment) {
 396                                                 td_sha1.appendChild(fragment);
 397                                         }
 398                                 }
 399                         }
 400                 } else {
 401                         //tr.removeChild(td_sha1); // DOM2 Core way
 402                         tr.deleteCell(0); // DOM2 HTML way
 403                 }
 404
 405                 /* <td class="linenr"><a class="linenr" href="?">123</a></td> */
 406                 var linenr_commit =
 407                         ('previous' in commit ? commit.previous : commit.sha1);
 408                 var linenr_filename =
 409                         ('file_parent' in commit ? commit.file_parent : commit.filename);
 410                 a_linenr.href = projectUrl + 'a=blame_incremental' +
 411                         ';hb=' + linenr_commit +
 412                         ';f='  + encodeURIComponent(linenr_filename) +
 413                         '#l' + (group.srcline + i);
 414
 415                 blamedLines++;
 416
 417                 //updateProgressInfo();
 418         }
 419 }
 420
 421 // ----------------------------------------------------------------------
 422
 423 /**#@+
 424  * @constant
 425  */
 426 var sha1Re = /^([0-9a-f]{40}) ([0-9]+) ([0-9]+) ([0-9]+)/;
 427 var infoRe = /^([a-z-]+) ?(.*)/;
 428 var endRe  = /^END ?([^ ]*) ?(.*)/;
 429 /**@-*/
 430
 431 var curCommit = new Commit();
 432 var curGroup  = {};
 433
 434 var pollTimer = null;
 435
 436 /**
 437  * Parse output from 'git blame --incremental [...]', received via
 438  * XMLHttpRequest from server (blamedataUrl), and call handleLine
 439  * (which updates page) as soon as blame entry is completed.
 440  *
 441  * @param {String[]} lines: new complete lines from blamedata server
 442  *
 443  * @globals commits, curCommit, curGroup, t_interval_server, cmds_server
 444  * @globals sha1Re, infoRe, endRe
 445  */
 446 function processBlameLines(lines) {
 447         var match;
 448
 449         for (var i = 0, len = lines.length; i < len; i++) {
 450
 451                 if ((match = sha1Re.exec(lines[i]))) {
 452                         var sha1 = match[1];
 453                         var srcline  = parseInt(match[2], 10);
 454                         var resline  = parseInt(match[3], 10);
 455                         var numlines = parseInt(match[4], 10);
 456
 457                         var c = commits[sha1];
 458                         if (!c) {
 459                                 c = new Commit(sha1);
 460                                 commits[sha1] = c;
 461                         }
 462                         curCommit = c;
 463
 464                         curGroup.srcline = srcline;
 465                         curGroup.resline = resline;
 466                         curGroup.numlines = numlines;
 467
 468                 } else if ((match = infoRe.exec(lines[i]))) {
 469                         var info = match[1];
 470                         var data = match[2];
 471                         switch (info) {
 472                         case 'filename':
 473                                 curCommit.filename = unquote(data);
 474                                 // 'filename' information terminates the entry
 475                                 handleLine(curCommit, curGroup);
 476                                 updateProgressInfo();
 477                                 break;
 478                         case 'author':
 479                                 curCommit.author = data;
 480                                 break;
 481                         case 'author-time':
 482                                 curCommit.authorTime = parseInt(data, 10);
 483                                 break;
 484                         case 'author-tz':
 485                                 curCommit.authorTimezone = data;
 486                                 break;
 487                         case 'previous':
 488                                 curCommit.nprevious++;
 489                                 // store only first 'previous' header
 490                                 if (!'previous' in curCommit) {
 491                                         var parts = data.split(' ', 2);
 492                                         curCommit.previous    = parts[0];
 493                                         curCommit.file_parent = unquote(parts[1]);
 494                                 }
 495                                 break;
 496                         case 'boundary':
 497                                 curCommit.boundary = true;
 498                                 break;
 499                         } // end switch
 500
 501                 } else if ((match = endRe.exec(lines[i]))) {
 502                         t_interval_server = match[1];
 503                         cmds_server = match[2];
 504
 505                 } else if (lines[i] !== '') {
 506                         // malformed line
 507
 508                 } // end if (match)
 509
 510         } // end for (lines)
 511 }
 512
 513 /**
 514  * Process new data and return pointer to end of processed part
 515  *
 516  * @param {String} unprocessed: new data (from nextReadPos)
 517  * @param {Number} nextReadPos: end of last processed data
 518  * @return {Number} end of processed data (new value for nextReadPos)
 519  */
 520 function processData(unprocessed, nextReadPos) {
 521         var lastLineEnd = unprocessed.lastIndexOf('\n');
 522         if (lastLineEnd !== -1) {
 523                 var lines = unprocessed.substring(0, lastLineEnd).split('\n');
 524                 nextReadPos += lastLineEnd + 1 /* 1 == '\n'.length */;
 525
 526                 processBlameLines(lines);
 527         } // end if
 528
 529         return nextReadPos;
 530 }
 531
 532 /**
 533  * Handle XMLHttpRequest errors
 534  *
 535  * @param {XMLHttpRequest} xhr: XMLHttpRequest object
 536  *
 537  * @globals pollTimer, commits
 538  */
 539 function handleError(xhr) {
 540         errorInfo('Server error: ' +
 541                 xhr.status + ' - ' + (xhr.statusText || 'Error contacting server'));
 542
 543         clearInterval(pollTimer);
 544         commits = {}; // free memory
 545 }
 546
 547 /**
 548  * Called after XMLHttpRequest finishes (loads)
 549  *
 550  * @param {XMLHttpRequest} xhr: XMLHttpRequest object (unused)
 551  *
 552  * @globals pollTimer, commits
 553  */
 554 function responseLoaded(xhr) {
 555         clearInterval(pollTimer);
 556
 557         fixColorsAndGroups();
 558         writeTimeInterval();
 559         commits = {}; // free memory
 560 }
 561
 562 /**
 563  * handler for XMLHttpRequest onreadystatechange event
 564  * @see startBlame
 565  *
 566  * @globals xhr
 567  */
 568 function handleResponse() {
 569
 570         /*
 571          * xhr.readyState
 572          *
 573          *  Value  Constant (W3C)    Description
 574          *  -------------------------------------------------------------------
 575          *  0      UNSENT            open() has not been called yet.
 576          *  1      OPENED            send() has not been called yet.
 577          *  2      HEADERS_RECEIVED  send() has been called, and headers
 578          *                           and status are available.
 579          *  3      LOADING           Downloading; responseText holds partial data.
 580          *  4      DONE              The operation is complete.
 581          */
 582
 583         if (xhr.readyState !== 4 && xhr.readyState !== 3) {
 584                 return;
 585         }
 586
 587         // the server returned error
 588         // try ... catch block is to work around bug in IE8
 589         try {
 590                 if (xhr.readyState === 3 && xhr.status !== 200) {
 591                         return;
 592                 }
 593         } catch (e) {
 594                 return;
 595         }
 596         if (xhr.readyState === 4 && xhr.status !== 200) {
 597                 handleError(xhr);
 598                 return;
 599         }
 600
 601         // In konqueror xhr.responseText is sometimes null here...
 602         if (xhr.responseText === null) {
 603                 return;
 604         }
 605
 606
 607         // extract new whole (complete) lines, and process them
 608         if (xhr.prevDataLength !== xhr.responseText.length) {
 609                 xhr.prevDataLength = xhr.responseText.length;
 610                 var unprocessed = xhr.responseText.substring(xhr.nextReadPos);
 611                 xhr.nextReadPos = processData(unprocessed, xhr.nextReadPos);
 612         }
 613
 614         // did we finish work?
 615         if (xhr.readyState === 4) {
 616                 responseLoaded(xhr);
 617         }
 618 }
 619
 620 // ============================================================
 621 // ------------------------------------------------------------
 622
 623 /**
 624  * Incrementally update line data in blame_incremental view in gitweb.
 625  *
 626  * @param {String} blamedataUrl: URL to server script generating blame data.
 627  * @param {String} bUrl: partial URL to project, used to generate links.
 628  *
 629  * Called from 'blame_incremental' view after loading table with
 630  * file contents, a base for blame view.
 631  *
 632  * @globals xhr, t0, projectUrl, div_progress_bar, totalLines, pollTimer
 633 */
 634 function startBlame(blamedataUrl, bUrl) {
 635
 636         xhr = createRequestObject();
 637         if (!xhr) {
 638                 errorInfo('ERROR: XMLHttpRequest not supported');
 639                 return;
 640         }
 641
 642         t0 = new Date();
 643         projectUrl = bUrl + (bUrl.indexOf('?') === -1 ? '?' : ';');
 644         if ((div_progress_bar = document.getElementById('progress_bar'))) {
 645                 //div_progress_bar.setAttribute('style', 'width: 100%;');
 646                 div_progress_bar.style.cssText = 'width: 100%;';
 647         }
 648         totalLines = countLines();
 649         updateProgressInfo();
 650
 651         /* add extra properties to xhr object to help processing response */
 652         xhr.prevDataLength = -1;  // used to detect if we have new data
 653         xhr.nextReadPos = 0;      // where unread part of response starts
 654
 655         xhr.onreadystatechange = handleResponse;
 656         //xhr.onreadystatechange = function () { handleResponse(xhr); };
 657
 658         xhr.open('GET', blamedataUrl);
 659         xhr.setRequestHeader('Accept', 'text/plain');
 660         xhr.send(null);
 661
 662         // not all browsers call onreadystatechange event on each server flush
 663         // poll response using timer every second to handle this issue
 664         pollTimer = setInterval(xhr.onreadystatechange, 1000);
 665 }
 666
 667 /* end of blame_incremental.js */