gitweb/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 projectUrl; // partial query + separator ('?' or ';')
  33
  34 // 'commits' is an associative map. It maps SHA1s to Commit objects.
  35 var commits = {};
  36
  37 /**
  38  * constructor for Commit objects, used in 'blame'
  39  * @class Represents a blamed commit
  40  * @param {String} sha1: SHA-1 identifier of a commit
  41  */
  42 function Commit(sha1) {
  43         if (this instanceof Commit) {
  44                 this.sha1 = sha1;
  45                 this.nprevious = 0; /* number of 'previous', effective parents */
  46         } else {
  47                 return new Commit(sha1);
  48         }
  49 }
  50
  51 /* ............................................................ */
  52 /* progress info, timing, error reporting */
  53
  54 var blamedLines = 0;
  55 var totalLines  = '???';
  56 var div_progress_bar;
  57 var div_progress_info;
  58
  59 /**
  60  * Detects how many lines does a blamed file have,
  61  * This information is used in progress info
  62  *
  63  * @returns {Number|String} Number of lines in file, or string '...'
  64  */
  65 function countLines() {
  66         var table =
  67                 document.getElementById('blame_table') ||
  68                 document.getElementsByTagName('table')[0];
  69
  70         if (table) {
  71                 return table.getElementsByTagName('tr').length - 1; // for header
  72         } else {
  73                 return '...';
  74         }
  75 }
  76
  77 /**
  78  * update progress info and length (width) of progress bar
  79  *
  80  * @globals div_progress_info, div_progress_bar, blamedLines, totalLines
  81  */
  82 function updateProgressInfo() {
  83         if (!div_progress_info) {
  84                 div_progress_info = document.getElementById('progress_info');
  85         }
  86         if (!div_progress_bar) {
  87                 div_progress_bar = document.getElementById('progress_bar');
  88         }
  89         if (!div_progress_info && !div_progress_bar) {
  90                 return;
  91         }
  92
  93         var percentage = Math.floor(100.0*blamedLines/totalLines);
  94
  95         if (div_progress_info) {
  96                 div_progress_info.firstChild.data  = blamedLines + ' / ' + totalLines +
  97                         ' (' + padLeftStr(percentage, 3, '\u00A0') + '%)';
  98         }
  99
 100         if (div_progress_bar) {
 101                 //div_progress_bar.setAttribute('style', 'width: '+percentage+'%;');
 102                 div_progress_bar.style.width = percentage + '%';
 103         }
 104 }
 105
 106
 107 var t_interval_server = '';
 108 var cmds_server = '';
 109 var t0 = new Date();
 110
 111 /**
 112  * write how much it took to generate data, and to run script
 113  *
 114  * @globals t0, t_interval_server, cmds_server
 115  */
 116 function writeTimeInterval() {
 117         var info_time = document.getElementById('generating_time');
 118         if (!info_time || !t_interval_server) {
 119                 return;
 120         }
 121         var t1 = new Date();
 122         info_time.firstChild.data += ' + (' +
 123                 t_interval_server + ' sec server blame_data / ' +
 124                 (t1.getTime() - t0.getTime())/1000 + ' sec client JavaScript)';
 125
 126         var info_cmds = document.getElementById('generating_cmd');
 127         if (!info_time || !cmds_server) {
 128                 return;
 129         }
 130         info_cmds.firstChild.data += ' + ' + cmds_server;
 131 }
 132
 133 /**
 134  * show an error message alert to user within page (in progress info area)
 135  * @param {String} str: plain text error message (no HTML)
 136  *
 137  * @globals div_progress_info
 138  */
 139 function errorInfo(str) {
 140         if (!div_progress_info) {
 141                 div_progress_info = document.getElementById('progress_info');
 142         }
 143         if (div_progress_info) {
 144                 div_progress_info.className = 'error';
 145                 div_progress_info.firstChild.data = str;
 146         }
 147 }
 148
 149 /* ............................................................ */
 150 /* coloring rows during blame_data (git blame --incremental) run */
 151
 152 /**
 153  * used to extract N from 'colorN', where N is a number,
 154  * @constant
 155  */
 156 var colorRe = /\bcolor([0-9]*)\b/;
 157
 158 /**
 159  * return N if <tr class="colorN">, otherwise return null
 160  * (some browsers require CSS class names to begin with letter)
 161  *
 162  * @param {HTMLElement} tr: table row element to check
 163  * @param {String} tr.className: 'class' attribute of tr element
 164  * @returns {Number|null} N if tr.className == 'colorN', otherwise null
 165  *
 166  * @globals colorRe
 167  */
 168 function getColorNo(tr) {
 169         if (!tr) {
 170                 return null;
 171         }
 172         var className = tr.className;
 173         if (className) {
 174                 var match = colorRe.exec(className);
 175                 if (match) {
 176                         return parseInt(match[1], 10);
 177                 }
 178         }
 179         return null;
 180 }
 181
 182 var colorsFreq = [0, 0, 0];
 183 /**
 184  * return one of given possible colors (currently least used one)
 185  * example: chooseColorNoFrom(2, 3) returns 2 or 3
 186  *
 187  * @param {Number[]} arguments: one or more numbers
 188  *        assumes that  1 <= arguments[i] <= colorsFreq.length
 189  * @returns {Number} Least used color number from arguments
 190  * @globals colorsFreq
 191  */
 192 function chooseColorNoFrom() {
 193         // choose the color which is least used
 194         var colorNo = arguments[0];
 195         for (var i = 1; i < arguments.length; i++) {
 196                 if (colorsFreq[arguments[i]-1] < colorsFreq[colorNo-1]) {
 197                         colorNo = arguments[i];
 198                 }
 199         }
 200         colorsFreq[colorNo-1]++;
 201         return colorNo;
 202 }
 203
 204 /**
 205  * given two neighbor <tr> elements, find color which would be different
 206  * from color of both of neighbors; used to 3-color blame table
 207  *
 208  * @param {HTMLElement} tr_prev
 209  * @param {HTMLElement} tr_next
 210  * @returns {Number} color number N such that
 211  * colorN != tr_prev.className && colorN != tr_next.className
 212  */
 213 function findColorNo(tr_prev, tr_next) {
 214         var color_prev = getColorNo(tr_prev);
 215         var color_next = getColorNo(tr_next);
 216
 217
 218         // neither of neighbors has color set
 219         // THEN we can use any of 3 possible colors
 220         if (!color_prev && !color_next) {
 221                 return chooseColorNoFrom(1,2,3);
 222         }
 223
 224         // either both neighbors have the same color,
 225         // or only one of neighbors have color set
 226         // THEN we can use any color except given
 227         var color;
 228         if (color_prev === color_next) {
 229                 color = color_prev; // = color_next;
 230         } else if (!color_prev) {
 231                 color = color_next;
 232         } else if (!color_next) {
 233                 color = color_prev;
 234         }
 235         if (color) {
 236                 return chooseColorNoFrom((color % 3) + 1, ((color+1) % 3) + 1);
 237         }
 238
 239         // neighbors have different colors
 240         // THEN there is only one color left
 241         return (3 - ((color_prev + color_next) % 3));
 242 }
 243
 244 /* ............................................................ */
 245 /* coloring rows like 'blame' after 'blame_data' finishes */
 246
 247 /**
 248  * returns true if given row element (tr) is first in commit group
 249  * to be used only after 'blame_data' finishes (after processing)
 250  *
 251  * @param {HTMLElement} tr: table row
 252  * @returns {Boolean} true if TR is first in commit group
 253  */
 254 function isStartOfGroup(tr) {
 255         return tr.firstChild.className === 'sha1';
 256 }
 257
 258 /**
 259  * change colors to use zebra coloring (2 colors) instead of 3 colors
 260  * concatenate neighbor commit groups belonging to the same commit
 261  *
 262  * @globals colorRe
 263  */
 264 function fixColorsAndGroups() {
 265         var colorClasses = ['light', 'dark'];
 266         var linenum = 1;
 267         var tr, prev_group;
 268         var colorClass = 0;
 269         var table =
 270                 document.getElementById('blame_table') ||
 271                 document.getElementsByTagName('table')[0];
 272
 273         while ((tr = document.getElementById('l'+linenum))) {
 274         // index origin is 0, which is table header; start from 1
 275         //while ((tr = table.rows[linenum])) { // <- it is slower
 276                 if (isStartOfGroup(tr, linenum, document)) {
 277                         if (prev_group &&
 278                             prev_group.firstChild.firstChild.href ===
 279                                     tr.firstChild.firstChild.href) {
 280                                 // we have to concatenate groups
 281                                 var prev_rows = prev_group.firstChild.rowSpan || 1;
 282                                 var curr_rows =         tr.firstChild.rowSpan || 1;
 283                                 prev_group.firstChild.rowSpan = prev_rows + curr_rows;
 284                                 //tr.removeChild(tr.firstChild);
 285                                 tr.deleteCell(0); // DOM2 HTML way
 286                         } else {
 287                                 colorClass = (colorClass + 1) % 2;
 288                                 prev_group = tr;
 289                         }
 290                 }
 291                 var tr_class = tr.className;
 292                 tr.className = tr_class.replace(colorRe, colorClasses[colorClass]);
 293                 linenum++;
 294         }
 295 }
 296
 297
 298 /* ============================================================ */
 299 /* main part: parsing response */
 300
 301 /**
 302  * Function called for each blame entry, as soon as it finishes.
 303  * It updates page via DOM manipulation, adding sha1 info, etc.
 304  *
 305  * @param {Commit} commit: blamed commit
 306  * @param {Object} group: object representing group of lines,
 307  *                        which blame the same commit (blame entry)
 308  *
 309  * @globals blamedLines
 310  */
 311 function handleLine(commit, group) {
 312         /*
 313            This is the structure of the HTML fragment we are working
 314            with:
 315
 316            <tr id="l123" class="">
 317              <td class="sha1" title=""><a href=""> </a></td>
 318              <td class="linenr"><a class="linenr" href="">123</a></td>
 319              <td class="pre"># times (my ext3 doesn&#39;t).</td>
 320            </tr>
 321         */
 322
 323         var resline = group.resline;
 324
 325         // format date and time string only once per commit
 326         if (!commit.info) {
 327                 /* e.g. 'Kay Sievers, 2005-08-07 21:49:46 +0200' */
 328                 commit.info = commit.author + ', ' +
 329                         formatDateISOLocal(commit.authorTime, commit.authorTimezone);
 330         }
 331
 332         // color depends on group of lines, not only on blamed commit
 333         var colorNo = findColorNo(
 334                 document.getElementById('l'+(resline-1)),
 335                 document.getElementById('l'+(resline+group.numlines))
 336         );
 337
 338         // loop over lines in commit group
 339         for (var i = 0; i < group.numlines; i++, resline++) {
 340                 var tr = document.getElementById('l'+resline);
 341                 if (!tr) {
 342                         break;
 343                 }
 344                 /*
 345                         <tr id="l123" class="">
 346                           <td class="sha1" title=""><a href=""> </a></td>
 347                           <td class="linenr"><a class="linenr" href="">123</a></td>
 348                           <td class="pre"># times (my ext3 doesn&#39;t).</td>
 349                         </tr>
 350                 */
 351                 var td_sha1  = tr.firstChild;
 352                 var a_sha1   = td_sha1.firstChild;
 353                 var a_linenr = td_sha1.nextSibling.firstChild;
 354
 355                 /* <tr id="l123" class=""> */
 356                 var tr_class = '';
 357                 if (colorNo !== null) {
 358                         tr_class = 'color'+colorNo;
 359                 }
 360                 if (commit.boundary) {
 361                         tr_class += ' boundary';
 362                 }
 363                 if (commit.nprevious === 0) {
 364                         tr_class += ' no-previous';
 365                 } else if (commit.nprevious > 1) {
 366                         tr_class += ' multiple-previous';
 367                 }
 368                 tr.className = tr_class;
 369
 370                 /* <td class="sha1" title="?" rowspan="?"><a href="?">?</a></td> */
 371                 if (i === 0) {
 372                         td_sha1.title = commit.info;
 373                         td_sha1.rowSpan = group.numlines;
 374
 375                         a_sha1.href = projectUrl + 'a=commit;h=' + commit.sha1;
 376                         if (a_sha1.firstChild) {
 377                                 a_sha1.firstChild.data = commit.sha1.substr(0, 8);
 378                         } else {
 379                                 a_sha1.appendChild(
 380                                         document.createTextNode(commit.sha1.substr(0, 8)));
 381                         }
 382                         if (group.numlines >= 2) {
 383                                 var fragment = document.createDocumentFragment();
 384                                 var br   = document.createElement("br");
 385                                 var match = commit.author.match(/\b([A-Z])\B/g);
 386                                 if (match) {
 387                                         var text = document.createTextNode(
 388                                                         match.join(''));
 389                                 }
 390                                 if (br && text) {
 391                                         var elem = fragment || td_sha1;
 392                                         elem.appendChild(br);
 393                                         elem.appendChild(text);
 394                                         if (fragment) {
 395                                                 td_sha1.appendChild(fragment);
 396                                         }
 397                                 }
 398                         }
 399                 } else {
 400                         //tr.removeChild(td_sha1); // DOM2 Core way
 401                         tr.deleteCell(0); // DOM2 HTML way
 402                 }
 403
 404                 /* <td class="linenr"><a class="linenr" href="?">123</a></td> */
 405                 var linenr_commit =
 406                         ('previous' in commit ? commit.previous : commit.sha1);
 407                 var linenr_filename =
 408                         ('file_parent' in commit ? commit.file_parent : commit.filename);
 409                 a_linenr.href = projectUrl + 'a=blame_incremental' +
 410                         ';hb=' + linenr_commit +
 411                         ';f='  + encodeURIComponent(linenr_filename) +
 412                         '#l' + (group.srcline + i);
 413
 414                 blamedLines++;
 415
 416                 //updateProgressInfo();
 417         }
 418 }
 419
 420 // ----------------------------------------------------------------------
 421
 422 /**#@+
 423  * @constant
 424  */
 425 var sha1Re = /^([0-9a-f]{40}) ([0-9]+) ([0-9]+) ([0-9]+)/;
 426 var infoRe = /^([a-z-]+) ?(.*)/;
 427 var endRe  = /^END ?([^ ]*) ?(.*)/;
 428 /**@-*/
 429
 430 var curCommit = new Commit();
 431 var curGroup  = {};
 432
 433 /**
 434  * Parse output from 'git blame --incremental [...]', received via
 435  * XMLHttpRequest from server (blamedataUrl), and call handleLine
 436  * (which updates page) as soon as blame entry is completed.
 437  *
 438  * @param {String[]} lines: new complete lines from blamedata server
 439  *
 440  * @globals commits, curCommit, curGroup, t_interval_server, cmds_server
 441  * @globals sha1Re, infoRe, endRe
 442  */
 443 function processBlameLines(lines) {
 444         var match;
 445
 446         for (var i = 0, len = lines.length; i < len; i++) {
 447
 448                 if ((match = sha1Re.exec(lines[i]))) {
 449                         var sha1 = match[1];
 450                         var srcline  = parseInt(match[2], 10);
 451                         var resline  = parseInt(match[3], 10);
 452                         var numlines = parseInt(match[4], 10);
 453
 454                         var c = commits[sha1];
 455                         if (!c) {
 456                                 c = new Commit(sha1);
 457                                 commits[sha1] = c;
 458                         }
 459                         curCommit = c;
 460
 461                         curGroup.srcline = srcline;
 462                         curGroup.resline = resline;
 463                         curGroup.numlines = numlines;
 464
 465                 } else if ((match = infoRe.exec(lines[i]))) {
 466                         var info = match[1];
 467                         var data = match[2];
 468                         switch (info) {
 469                         case 'filename':
 470                                 curCommit.filename = unquote(data);
 471                                 // 'filename' information terminates the entry
 472                                 handleLine(curCommit, curGroup);
 473                                 updateProgressInfo();
 474                                 break;
 475                         case 'author':
 476                                 curCommit.author = data;
 477                                 break;
 478                         case 'author-time':
 479                                 curCommit.authorTime = parseInt(data, 10);
 480                                 break;
 481                         case 'author-tz':
 482                                 curCommit.authorTimezone = data;
 483                                 break;
 484                         case 'previous':
 485                                 curCommit.nprevious++;
 486                                 // store only first 'previous' header
 487                                 if (!'previous' in curCommit) {
 488                                         var parts = data.split(' ', 2);
 489                                         curCommit.previous    = parts[0];
 490                                         curCommit.file_parent = unquote(parts[1]);
 491                                 }
 492                                 break;
 493                         case 'boundary':
 494                                 curCommit.boundary = true;
 495                                 break;
 496                         } // end switch
 497
 498                 } else if ((match = endRe.exec(lines[i]))) {
 499                         t_interval_server = match[1];
 500                         cmds_server = match[2];
 501
 502                 } else if (lines[i] !== '') {
 503                         // malformed line
 504
 505                 } // end if (match)
 506
 507         } // end for (lines)
 508 }
 509
 510 /**
 511  * Process new data and return pointer to end of processed part
 512  *
 513  * @param {String} unprocessed: new data (from nextReadPos)
 514  * @param {Number} nextReadPos: end of last processed data
 515  * @return {Number} end of processed data (new value for nextReadPos)
 516  */
 517 function processData(unprocessed, nextReadPos) {
 518         var lastLineEnd = unprocessed.lastIndexOf('\n');
 519         if (lastLineEnd !== -1) {
 520                 var lines = unprocessed.substring(0, lastLineEnd).split('\n');
 521                 nextReadPos += lastLineEnd + 1 /* 1 == '\n'.length */;
 522
 523                 processBlameLines(lines);
 524         } // end if
 525
 526         return nextReadPos;
 527 }
 528
 529 /**
 530  * Handle XMLHttpRequest errors
 531  *
 532  * @param {XMLHttpRequest} xhr: XMLHttpRequest object
 533  * @param {Number} [xhr.pollTimer] ID of the timeout to clear
 534  *
 535  * @globals commits
 536  */
 537 function handleError(xhr) {
 538         errorInfo('Server error: ' +
 539                 xhr.status + ' - ' + (xhr.statusText || 'Error contacting server'));
 540
 541         if (typeof xhr.pollTimer === "number") {
 542                 clearTimeout(xhr.pollTimer);
 543                 delete xhr.pollTimer;
 544         }
 545         commits = {}; // free memory
 546 }
 547
 548 /**
 549  * Called after XMLHttpRequest finishes (loads)
 550  *
 551  * @param {XMLHttpRequest} xhr: XMLHttpRequest object
 552  * @param {Number} [xhr.pollTimer] ID of the timeout to clear
 553  *
 554  * @globals commits
 555  */
 556 function responseLoaded(xhr) {
 557         if (typeof xhr.pollTimer === "number") {
 558                 clearTimeout(xhr.pollTimer);
 559                 delete xhr.pollTimer;
 560         }
 561
 562         fixColorsAndGroups();
 563         writeTimeInterval();
 564         commits = {}; // free memory
 565 }
 566
 567 /**
 568  * handler for XMLHttpRequest onreadystatechange event
 569  * @see startBlame
 570  *
 571  * @param {XMLHttpRequest} xhr: XMLHttpRequest object
 572  * @param {Number} xhr.prevDataLength: previous value of xhr.responseText.length
 573  * @param {Number} xhr.nextReadPos: start of unread part of xhr.responseText
 574  * @param {Number} [xhr.pollTimer] ID of the timeout (to reset or cancel)
 575  * @param {Boolean} fromTimer: if handler was called from timer
 576  */
 577 function handleResponse(xhr, fromTimer) {
 578
 579         /*
 580          * xhr.readyState
 581          *
 582          *  Value  Constant (W3C)    Description
 583          *  -------------------------------------------------------------------
 584          *  0      UNSENT            open() has not been called yet.
 585          *  1      OPENED            send() has not been called yet.
 586          *  2      HEADERS_RECEIVED  send() has been called, and headers
 587          *                           and status are available.
 588          *  3      LOADING           Downloading; responseText holds partial data.
 589          *  4      DONE              The operation is complete.
 590          */
 591
 592         if (xhr.readyState !== 4 && xhr.readyState !== 3) {
 593                 return;
 594         }
 595
 596         // the server returned error
 597         // try ... catch block is to work around bug in IE8
 598         try {
 599                 if (xhr.readyState === 3 && xhr.status !== 200) {
 600                         return;
 601                 }
 602         } catch (e) {
 603                 return;
 604         }
 605         if (xhr.readyState === 4 && xhr.status !== 200) {
 606                 handleError(xhr);
 607                 return;
 608         }
 609
 610         // In konqueror xhr.responseText is sometimes null here...
 611         if (xhr.responseText === null) {
 612                 return;
 613         }
 614
 615
 616         // extract new whole (complete) lines, and process them
 617         if (xhr.prevDataLength !== xhr.responseText.length) {
 618                 xhr.prevDataLength = xhr.responseText.length;
 619                 var unprocessed = xhr.responseText.substring(xhr.nextReadPos);
 620                 xhr.nextReadPos = processData(unprocessed, xhr.nextReadPos);
 621         }
 622
 623         // did we finish work?
 624         if (xhr.readyState === 4) {
 625                 responseLoaded(xhr);
 626                 return;
 627         }
 628
 629         // if we get from timer, we have to restart it
 630         // otherwise onreadystatechange gives us partial response, timer not needed
 631         if (fromTimer) {
 632                 setTimeout(function () {
 633                         handleResponse(xhr, true);
 634                 }, 1000);
 635
 636         } else if (typeof xhr.pollTimer === "number") {
 637                 clearTimeout(xhr.pollTimer);
 638                 delete xhr.pollTimer;
 639         }
 640 }
 641
 642 // ============================================================
 643 // ------------------------------------------------------------
 644
 645 /**
 646  * Incrementally update line data in blame_incremental view in gitweb.
 647  *
 648  * @param {String} blamedataUrl: URL to server script generating blame data.
 649  * @param {String} bUrl: partial URL to project, used to generate links.
 650  *
 651  * Called from 'blame_incremental' view after loading table with
 652  * file contents, a base for blame view.
 653  *
 654  * @globals t0, projectUrl, div_progress_bar, totalLines
 655 */
 656 function startBlame(blamedataUrl, bUrl) {
 657
 658         var xhr = createRequestObject();
 659         if (!xhr) {
 660                 errorInfo('ERROR: XMLHttpRequest not supported');
 661                 return;
 662         }
 663
 664         t0 = new Date();
 665         projectUrl = bUrl + (bUrl.indexOf('?') === -1 ? '?' : ';');
 666         if ((div_progress_bar = document.getElementById('progress_bar'))) {
 667                 //div_progress_bar.setAttribute('style', 'width: 100%;');
 668                 div_progress_bar.style.cssText = 'width: 100%;';
 669         }
 670         totalLines = countLines();
 671         updateProgressInfo();
 672
 673         /* add extra properties to xhr object to help processing response */
 674         xhr.prevDataLength = -1;  // used to detect if we have new data
 675         xhr.nextReadPos = 0;      // where unread part of response starts
 676
 677         xhr.onreadystatechange = function () {
 678                 handleResponse(xhr, false);
 679         };
 680
 681         xhr.open('GET', blamedataUrl);
 682         xhr.setRequestHeader('Accept', 'text/plain');
 683         xhr.send(null);
 684
 685         // not all browsers call onreadystatechange event on each server flush
 686         // poll response using timer every second to handle this issue
 687         xhr.pollTimer = setTimeout(function () {
 688                 handleResponse(xhr, true);
 689         }, 1000);
 690 }
 691
 692 /* end of blame_incremental.js */