src/filter_http_rewrite.cpp

   1 /* This file is part of Metaproxy.
   2    Copyright (C) 2005-2013 Index Data
   3
   4 Metaproxy is free software; you can redistribute it and/or modify it under
   5 the terms of the GNU General Public License as published by the Free
   6 Software Foundation; either version 2, or (at your option) any later
   7 version.
   8
   9 Metaproxy is distributed in the hope that it will be useful, but WITHOUT ANY
  10 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12 for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17 */
  18
  19 #include "config.hpp"
  20 #include <metaproxy/filter.hpp>
  21 #include <metaproxy/package.hpp>
  22 #include <metaproxy/util.hpp>
  23 #include "filter_http_rewrite.hpp"
  24 #include "html_parser.hpp"
  25
  26 #include <yaz/zgdu.h>
  27 #include <yaz/log.h>
  28
  29 #include <stack>
  30 #include <boost/regex.hpp>
  31 #include <boost/lexical_cast.hpp>
  32 #include <boost/algorithm/string.hpp>
  33
  34 #include <map>
  35
  36 namespace mp = metaproxy_1;
  37 namespace yf = mp::filter;
  38
  39 namespace metaproxy_1 {
  40     namespace filter {
  41         class HttpRewrite::Replace {
  42         public:
  43             bool start_anchor;
  44             boost::regex re;
  45             boost::smatch what;
  46             std::string recipe;
  47             std::map<int, std::string> group_index;
  48             std::string sub_vars(
  49                 const std::map<std::string, std::string> & vars) const;
  50             void parse_groups(std::string pattern);
  51         };
  52
  53         class HttpRewrite::Rule {
  54         public:
  55             std::list<Replace> replace_list;
  56             bool test_patterns(
  57                 std::map<std::string, std::string> &vars,
  58                 std::string &txt, bool anchor);
  59         };
  60         class HttpRewrite::Within {
  61         public:
  62             std::string header;
  63             std::string attr;
  64             std::string tag;
  65             bool reqline;
  66             RulePtr rule;
  67         };
  68
  69         class HttpRewrite::Content {
  70         public:
  71             std::string type;
  72             boost::regex content_re;
  73             std::list<Within> within_list;
  74             void configure(const xmlNode *ptr,
  75                            std::map<std::string, RulePtr > &rules);
  76             void quoted_literal(std::string &content,
  77                                 std::map<std::string, std::string> &vars) const;
  78             void parse(int verbose, std::string &content,
  79                        std::map<std::string, std::string> & vars) const;
  80         };
  81         class HttpRewrite::Phase {
  82         public:
  83             Phase();
  84             int m_verbose;
  85             std::list<Content> content_list;
  86             void rewrite_reqline(mp::odr & o, Z_HTTP_Request *hreq,
  87                 std::map<std::string, std::string> & vars) const;
  88             void rewrite_headers(mp::odr & o, Z_HTTP_Header *headers,
  89                 std::map<std::string, std::string> & vars) const;
  90             void rewrite_body(mp::odr & o,
  91                               const char *content_type,
  92                               char **content_buf, int *content_len,
  93                               std::map<std::string, std::string> & vars) const;
  94         };
  95         class HttpRewrite::Event : public HTMLParserEvent {
  96             void openTagStart(const char *tag, int tag_len);
  97             void anyTagEnd(const char *tag, int tag_len, int close_it);
  98             void attribute(const char *tag, int tag_len,
  99                            const char *attr, int attr_len,
 100                            const char *value, int val_len,
 101                            const char *sep);
 102             void closeTag(const char *tag, int tag_len);
 103             void text(const char *value, int len);
 104             const Content *m_content;
 105             WRBUF m_w;
 106             std::stack<std::list<Within>::const_iterator> s_within;
 107             std::map<std::string, std::string> &m_vars;
 108         public:
 109             Event(const Content *p, std::map<std::string, std::string> &vars);
 110             ~Event();
 111             const char *result();
 112         };
 113     }
 114 }
 115
 116 yf::HttpRewrite::HttpRewrite() :
 117     req_phase(new Phase), res_phase(new Phase)
 118 {
 119 }
 120
 121 yf::HttpRewrite::~HttpRewrite()
 122 {
 123 }
 124
 125 void yf::HttpRewrite::process(mp::Package & package) const
 126 {
 127     yaz_log(YLOG_LOG, "HttpRewrite begins....");
 128     Z_GDU *gdu = package.request().get();
 129     //map of request/response vars
 130     std::map<std::string, std::string> vars;
 131     //we have an http req
 132     if (gdu && gdu->which == Z_GDU_HTTP_Request)
 133     {
 134         Z_HTTP_Request *hreq = gdu->u.HTTP_Request;
 135         mp::odr o;
 136         req_phase->rewrite_reqline(o, hreq, vars);
 137         yaz_log(YLOG_LOG, ">> Request headers");
 138         req_phase->rewrite_headers(o, hreq->headers, vars);
 139         req_phase->rewrite_body(o,
 140                                 z_HTTP_header_lookup(hreq->headers,
 141                                                      "Content-Type"),
 142                                 &hreq->content_buf, &hreq->content_len,
 143                                 vars);
 144         package.request() = gdu;
 145     }
 146     package.move();
 147     gdu = package.response().get();
 148     if (gdu && gdu->which == Z_GDU_HTTP_Response)
 149     {
 150         Z_HTTP_Response *hres = gdu->u.HTTP_Response;
 151         yaz_log(YLOG_LOG, "Response code %d", hres->code);
 152         mp::odr o;
 153         yaz_log(YLOG_LOG, "<< Respose headers");
 154         res_phase->rewrite_headers(o, hres->headers, vars);
 155         res_phase->rewrite_body(o,
 156                                 z_HTTP_header_lookup(hres->headers,
 157                                                      "Content-Type"),
 158                                 &hres->content_buf, &hres->content_len,
 159                                 vars);
 160         package.response() = gdu;
 161     }
 162 }
 163
 164 void yf::HttpRewrite::Phase::rewrite_reqline (mp::odr & o,
 165         Z_HTTP_Request *hreq,
 166         std::map<std::string, std::string> & vars) const
 167 {
 168     //rewrite the request line
 169     std::string path;
 170     if (strstr(hreq->path, "http://") == hreq->path)
 171     {
 172         yaz_log(YLOG_LOG, "Path in the method line is absolute, "
 173             "possibly a proxy request");
 174         path += hreq->path;
 175     }
 176     else
 177     {
 178         //TODO what about proto
 179         const char *host = z_HTTP_header_lookup(hreq->headers, "Host");
 180         if (!host)
 181             return;
 182
 183         path += "http://";
 184         path += host;
 185         path += hreq->path;
 186     }
 187
 188     std::list<Content>::const_iterator cit = content_list.begin();
 189     for (; cit != content_list.end(); cit++)
 190         if (cit->type == "headers")
 191             break;
 192
 193     if (cit == content_list.end())
 194         return;
 195
 196     std::list<Within>::const_iterator it = cit->within_list.begin();
 197     for (; it != cit->within_list.end(); it++)
 198         if (it->reqline)
 199         {
 200             yaz_log(YLOG_LOG, "Proxy request URL is %s", path.c_str());
 201             if (it->rule->test_patterns(vars, path, true))
 202             {
 203                 yaz_log(YLOG_LOG, "Rewritten request URL is %s", path.c_str());
 204                 hreq->path = odr_strdup(o, path.c_str());
 205             }
 206         }
 207 }
 208
 209 void yf::HttpRewrite::Phase::rewrite_headers(mp::odr & o,
 210         Z_HTTP_Header *headers,
 211         std::map<std::string, std::string> & vars) const
 212 {
 213     std::list<Content>::const_iterator cit = content_list.begin();
 214     for (; cit != content_list.end(); cit++)
 215         if (cit->type == "headers")
 216             break;
 217
 218     if (cit == content_list.end())
 219         return;
 220
 221     for (Z_HTTP_Header *header = headers; header; header = header->next)
 222     {
 223         std::list<Within>::const_iterator it = cit->within_list.begin();
 224         for (; it != cit->within_list.end(); it++)
 225         {
 226             if (it->header.length() > 0 &&
 227                 yaz_strcasecmp(it->header.c_str(), header->name) == 0)
 228             {
 229                 std::string sheader(header->name);
 230                 sheader += ": ";
 231                 sheader += header->value;
 232
 233                 if (it->rule->test_patterns(vars, sheader, true))
 234                 {
 235                     size_t pos = sheader.find(": ");
 236                     if (pos == std::string::npos)
 237                     {
 238                         yaz_log(YLOG_LOG, "Header malformed during rewrite, ignoring");
 239                         continue;
 240                     }
 241                     header->name = odr_strdup(
 242                         o, sheader.substr(0, pos).c_str());
 243                     header->value = odr_strdup(
 244                         o, sheader.substr(pos + 2, std::string::npos).c_str());
 245                 }
 246             }
 247         }
 248     }
 249 }
 250
 251 void yf::HttpRewrite::Phase::rewrite_body(
 252     mp::odr &o,
 253     const char *content_type,
 254     char **content_buf,
 255     int *content_len,
 256     std::map<std::string, std::string> & vars) const
 257 {
 258     std::list<Content>::const_iterator cit = content_list.begin();
 259     for (; cit != content_list.end(); cit++)
 260     {
 261         yaz_log(YLOG_LOG, "rewrite_body: content_type=%s type=%s",
 262                 content_type, cit->type.c_str());
 263         if (cit->type != "headers"
 264             && regex_match(content_type, cit->content_re))
 265             break;
 266     }
 267     if (cit == content_list.end())
 268         return;
 269
 270     if (*content_buf)
 271     {
 272         int i;
 273         for (i = 0; i < *content_len; i++)
 274             if ((*content_buf)[i] == 0)
 275                 return;  // binary content. skip
 276
 277         std::string content(*content_buf, *content_len);
 278         cit->parse(m_verbose, content, vars);
 279         *content_buf = odr_strdup(o, content.c_str());
 280         *content_len = strlen(*content_buf);
 281     }
 282 }
 283
 284 yf::HttpRewrite::Event::Event(const Content *p,
 285                               std::map<std::string, std::string> & vars
 286     ) : m_content(p), m_vars(vars)
 287 {
 288     m_w = wrbuf_alloc();
 289 }
 290
 291 yf::HttpRewrite::Event::~Event()
 292 {
 293     wrbuf_destroy(m_w);
 294 }
 295
 296 const char *yf::HttpRewrite::Event::result()
 297 {
 298     return wrbuf_cstr(m_w);
 299 }
 300
 301 void yf::HttpRewrite::Event::openTagStart(const char *tag, int tag_len)
 302 {
 303     wrbuf_putc(m_w, '<');
 304     wrbuf_write(m_w, tag, tag_len);
 305
 306     std::string t(tag, tag_len);
 307     std::list<Within>::const_iterator it = m_content->within_list.begin();
 308     for (; it != m_content->within_list.end(); it++)
 309     {
 310         if (it->tag.length() > 0 && yaz_strcasecmp(it->tag.c_str(),
 311                                                    t.c_str()) == 0)
 312         {
 313             std::vector<std::string> attr;
 314             boost::split(attr, it->attr, boost::is_any_of(","));
 315             size_t i;
 316             for (i = 0; i < attr.size(); i++)
 317             {
 318                 if (attr[i].compare("#text") == 0)
 319                 {
 320                     s_within.push(it);
 321                     return;
 322                 }
 323             }
 324         }
 325     }
 326 }
 327
 328 void yf::HttpRewrite::Event::anyTagEnd(const char *tag, int tag_len,
 329                                        int close_it)
 330 {
 331     if (close_it)
 332     {
 333         if (!s_within.empty())
 334         {
 335             std::list<Within>::const_iterator it = s_within.top();
 336             std::string t(tag, tag_len);
 337             if (yaz_strcasecmp(it->tag.c_str(), t.c_str()) == 0)
 338                 s_within.pop();
 339         }
 340     }
 341     if (close_it)
 342         wrbuf_putc(m_w, '/');
 343     wrbuf_putc(m_w, '>');
 344 }
 345
 346 void yf::HttpRewrite::Event::attribute(const char *tag, int tag_len,
 347                                        const char *attr, int attr_len,
 348                                        const char *value, int val_len,
 349                                        const char *sep)
 350 {
 351     std::list<Within>::const_iterator it = m_content->within_list.begin();
 352     bool subst = false;
 353
 354     for (; it != m_content->within_list.end(); it++)
 355     {
 356         std::string t(tag, tag_len);
 357         if (it->tag.length() == 0 ||
 358             yaz_strcasecmp(it->tag.c_str(), t.c_str()) == 0)
 359         {
 360             std::string a(attr, attr_len);
 361             std::vector<std::string> attr;
 362             boost::split(attr, it->attr, boost::is_any_of(","));
 363             size_t i;
 364             for (i = 0; i < attr.size(); i++)
 365             {
 366                 if (attr[i].compare("#text") &&
 367                     yaz_strcasecmp(attr[i].c_str(), a.c_str()) == 0)
 368                     subst = true;
 369             }
 370         }
 371         if (subst)
 372             break;
 373     }
 374
 375     wrbuf_putc(m_w, ' ');
 376     wrbuf_write(m_w, attr, attr_len);
 377     if (value)
 378     {
 379         wrbuf_puts(m_w, "=");
 380         wrbuf_puts(m_w, sep);
 381
 382         std::string output;
 383         if (subst)
 384         {
 385             std::string s(value, val_len);
 386             it->rule->test_patterns(m_vars, s, true);
 387             wrbuf_puts(m_w, s.c_str());
 388         }
 389         else
 390             wrbuf_write(m_w, value, val_len);
 391         wrbuf_puts(m_w, sep);
 392     }
 393 }
 394
 395 void yf::HttpRewrite::Event::closeTag(const char *tag, int tag_len)
 396 {
 397     if (!s_within.empty())
 398     {
 399         std::list<Within>::const_iterator it = s_within.top();
 400         std::string t(tag, tag_len);
 401         if (yaz_strcasecmp(it->tag.c_str(), t.c_str()) == 0)
 402             s_within.pop();
 403     }
 404     wrbuf_puts(m_w, "</");
 405     wrbuf_write(m_w, tag, tag_len);
 406 }
 407
 408 void yf::HttpRewrite::Event::text(const char *value, int len)
 409 {
 410     std::list<Within>::const_iterator it = m_content->within_list.end();
 411     if (!s_within.empty())
 412         it = s_within.top();
 413     if (it != m_content->within_list.end())
 414     {
 415         std::string s(value, len);
 416         it->rule->test_patterns(m_vars, s, false);
 417         wrbuf_puts(m_w, s.c_str());
 418     }
 419     else
 420         wrbuf_write(m_w, value, len);
 421 }
 422
 423 bool yf::HttpRewrite::Rule::test_patterns(
 424     std::map<std::string, std::string> & vars,
 425     std::string & txt, bool anchor)
 426 {
 427     bool replaces = false;
 428     bool first = anchor;
 429     std::string out;
 430     std::string::const_iterator start, end;
 431     start = txt.begin();
 432     end = txt.end();
 433     while (1)
 434     {
 435         std::list<Replace>::iterator bit = replace_list.end();
 436         {
 437             std::string::const_iterator best_pos = txt.end();
 438             std::list<Replace>::iterator it = replace_list.begin();
 439             for (; it != replace_list.end(); it++)
 440             {
 441                 if (it->start_anchor && !first)
 442                     continue;
 443                 if (regex_search(start, end, it->what, it->re))
 444                 {
 445                     if (it->what[0].first < best_pos)
 446                     {
 447                         best_pos = it->what[0].first;
 448                         bit = it;
 449                     }
 450                 }
 451             }
 452             if (bit == replace_list.end())
 453                 break;
 454         }
 455         first = false;
 456         replaces = true;
 457         size_t i;
 458         for (i = 1; i < bit->what.size(); ++i)
 459         {
 460             //check if the group is named
 461             std::map<int, std::string>::const_iterator git
 462                 = bit->group_index.find(i);
 463             if (git != bit->group_index.end())
 464             {   //it is
 465                 vars[git->second] = bit->what[i];
 466             }
 467
 468         }
 469         //prepare replacement string
 470         std::string rvalue = bit->sub_vars(vars);
 471         yaz_log(YLOG_LOG, "! Rewritten '%s' to '%s'",
 472                 bit->what.str(0).c_str(), rvalue.c_str());
 473         out.append(start, bit->what[0].first);
 474         out.append(rvalue);
 475         start = bit->what[0].second; //move search forward
 476     }
 477     out.append(start, end);
 478     txt = out;
 479     return replaces;
 480 }
 481
 482 void yf::HttpRewrite::Replace::parse_groups(std::string pattern)
 483 {
 484     int gnum = 0;
 485     bool esc = false;
 486     const std::string &str = pattern;
 487     std::string res;
 488     start_anchor = str[0] == '^';
 489     yaz_log(YLOG_LOG, "Parsing groups from '%s'", str.c_str());
 490     for (size_t i = 0; i < str.size(); ++i)
 491     {
 492         res += str[i];
 493         if (!esc && str[i] == '\\')
 494         {
 495             esc = true;
 496             continue;
 497         }
 498         if (!esc && str[i] == '(') //group starts
 499         {
 500             gnum++;
 501             if (i+1 < str.size() && str[i+1] == '?') //group with attrs
 502             {
 503                 i++;
 504                 if (i+1 < str.size() && str[i+1] == ':') //non-capturing
 505                 {
 506                     if (gnum > 0) gnum--;
 507                     res += str[i];
 508                     i++;
 509                     res += str[i];
 510                     continue;
 511                 }
 512                 if (i+1 < str.size() && str[i+1] == 'P') //optional, python
 513                     i++;
 514                 if (i+1 < str.size() && str[i+1] == '<') //named
 515                 {
 516                     i++;
 517                     std::string gname;
 518                     bool term = false;
 519                     while (++i < str.size())
 520                     {
 521                         if (str[i] == '>') { term = true; break; }
 522                         if (!isalnum(str[i]))
 523                             throw mp::filter::FilterException
 524                                 ("Only alphanumeric chars allowed, found "
 525                                  " in '"
 526                                  + str
 527                                  + "' at "
 528                                  + boost::lexical_cast<std::string>(i));
 529                         gname += str[i];
 530                     }
 531                     if (!term)
 532                         throw mp::filter::FilterException
 533                             ("Unterminated group name '" + gname
 534                              + " in '" + str +"'");
 535                     group_index[gnum] = gname;
 536                     yaz_log(YLOG_LOG, "Found named group '%s' at $%d",
 537                             gname.c_str(), gnum);
 538                 }
 539             }
 540         }
 541         esc = false;
 542     }
 543     re = res;
 544 }
 545
 546 std::string yf::HttpRewrite::Replace::sub_vars(
 547     const std::map<std::string, std::string> & vars) const
 548 {
 549     std::string out;
 550     bool esc = false;
 551     const std::string & in = recipe;
 552     for (size_t i = 0; i < in.size(); ++i)
 553     {
 554         if (!esc && in[i] == '\\')
 555         {
 556             esc = true;
 557             continue;
 558         }
 559         if (!esc && in[i] == '$') //var
 560         {
 561             if (i+1 < in.size() && in[i+1] == '{') //ref prefix
 562             {
 563                 ++i;
 564                 std::string name;
 565                 bool term = false;
 566                 while (++i < in.size())
 567                 {
 568                     if (in[i] == '}') { term = true; break; }
 569                     name += in[i];
 570                 }
 571                 if (!term) throw mp::filter::FilterException
 572                     ("Unterminated var ref in '"+in+"' at "
 573                      + boost::lexical_cast<std::string>(i));
 574                 std::map<std::string, std::string>::const_iterator it
 575                     = vars.find(name);
 576                 if (it != vars.end())
 577                 {
 578                     out += it->second;
 579                 }
 580             }
 581             else
 582             {
 583                 throw mp::filter::FilterException
 584                     ("Malformed or trimmed var ref in '"
 585                      +in+"' at "+boost::lexical_cast<std::string>(i));
 586             }
 587             continue;
 588         }
 589         //passthru
 590         out += in[i];
 591         esc = false;
 592     }
 593     return out;
 594 }
 595
 596 yf::HttpRewrite::Phase::Phase() : m_verbose(0)
 597 {
 598 }
 599
 600 void yf::HttpRewrite::Content::parse(
 601     int verbose,
 602     std::string &content,
 603     std::map<std::string, std::string> &vars) const
 604 {
 605     if (type == "html")
 606     {
 607         HTMLParser parser;
 608         Event ev(this, vars);
 609
 610         parser.set_verbose(verbose);
 611
 612         parser.parse(ev, content.c_str());
 613         content = ev.result();
 614     }
 615     if (type == "quoted-literal")
 616     {
 617         quoted_literal(content, vars);
 618     }
 619 }
 620
 621 void yf::HttpRewrite::Content::quoted_literal(
 622     std::string &content,
 623     std::map<std::string, std::string> &vars) const
 624 {
 625     std::string res;
 626     const char *cp = content.c_str();
 627     const char *cp0 = cp;
 628     while (*cp)
 629     {
 630         if (*cp == '"' || *cp == '\'')
 631         {
 632             int m = *cp;
 633             cp++;
 634             res.append(cp0, cp - cp0);
 635             cp0 = cp;
 636             while (*cp)
 637             {
 638                 if (cp[-1] != '\\' && *cp == m)
 639                     break;
 640                 if (*cp == '\n')
 641                     break;
 642                 cp++;
 643             }
 644             if (!*cp)
 645                 break;
 646             std::list<Within>::const_iterator it = within_list.begin();
 647             std::string s(cp0, cp - cp0);
 648             if (it != within_list.end())
 649                 it->rule->test_patterns(vars, s, true);
 650             cp0 = cp;
 651             res.append(s);
 652         }
 653         else if (*cp == '/' && cp[1] == '/')
 654         {
 655             while (cp[1] && cp[1] != '\n')
 656                 cp++;
 657         }
 658         cp++;
 659     }
 660     res.append(cp0, cp - cp0);
 661     content = res;
 662 }
 663
 664 void yf::HttpRewrite::Content::configure(
 665     const xmlNode *ptr, std::map<std::string, RulePtr > &rules)
 666 {
 667     for (; ptr; ptr = ptr->next)
 668     {
 669         if (ptr->type != XML_ELEMENT_NODE)
 670             continue;
 671         if (!strcmp((const char *) ptr->name, "within"))
 672         {
 673             static const char *names[6] =
 674                 { "header", "attr", "tag", "rule", "reqline", 0 };
 675             std::string values[5];
 676             mp::xml::parse_attr(ptr, names, values);
 677             Within w;
 678             w.header = values[0];
 679             w.attr = values[1];
 680             w.tag = values[2];
 681             std::map<std::string,RulePtr>::const_iterator it =
 682                 rules.find(values[3]);
 683             if (it == rules.end())
 684                 throw mp::filter::FilterException
 685                     ("Reference to non-existing rule '" + values[3] +
 686                      "' in http_rewrite filter");
 687             w.rule = it->second;
 688             w.reqline = values[4] == "1";
 689             within_list.push_back(w);
 690         }
 691     }
 692 }
 693
 694 void yf::HttpRewrite::configure_phase(const xmlNode *ptr, Phase &phase)
 695 {
 696     static const char *names[2] = { "verbose", 0 };
 697     std::string values[1];
 698     values[0] = "0";
 699     mp::xml::parse_attr(ptr, names, values);
 700
 701     phase.m_verbose = atoi(values[0].c_str());
 702
 703     std::map<std::string, RulePtr > rules;
 704     for (ptr = ptr->children; ptr; ptr = ptr->next)
 705     {
 706         if (ptr->type != XML_ELEMENT_NODE)
 707             continue;
 708         else if (!strcmp((const char *) ptr->name, "rule"))
 709         {
 710             static const char *names[2] = { "name", 0 };
 711             std::string values[1];
 712             values[0] = "default";
 713             mp::xml::parse_attr(ptr, names, values);
 714
 715             RulePtr rule(new Rule);
 716             for (xmlNode *p = ptr->children; p; p = p->next)
 717             {
 718                 if (p->type != XML_ELEMENT_NODE)
 719                     continue;
 720                 if (!strcmp((const char *) p->name, "rewrite"))
 721                 {
 722                     Replace replace;
 723                     std::string from;
 724                     const struct _xmlAttr *attr;
 725                     for (attr = p->properties; attr; attr = attr->next)
 726                     {
 727                         if (!strcmp((const char *) attr->name,  "from"))
 728                             from = mp::xml::get_text(attr->children);
 729                         else if (!strcmp((const char *) attr->name,  "to"))
 730                             replace.recipe = mp::xml::get_text(attr->children);
 731                         else
 732                             throw mp::filter::FilterException
 733                                 ("Bad attribute "
 734                                  + std::string((const char *) attr->name)
 735                                  + " in rewrite section of http_rewrite");
 736                     }
 737                     yaz_log(YLOG_LOG, "Found rewrite rule from '%s' to '%s'",
 738                             from.c_str(), replace.recipe.c_str());
 739                     if (!from.empty())
 740                     {
 741                         replace.parse_groups(from);
 742                         rule->replace_list.push_back(replace);
 743                     }
 744                 }
 745                 else
 746                     throw mp::filter::FilterException
 747                         ("Bad element "
 748                          + std::string((const char *) p->name)
 749                          + " in http_rewrite filter");
 750             }
 751             rules[values[0]] = rule;
 752         }
 753         else if (!strcmp((const char *) ptr->name, "content"))
 754         {
 755             static const char *names[3] =
 756                 { "type", "mime", 0 };
 757             std::string values[2];
 758             mp::xml::parse_attr(ptr, names, values);
 759             if (values[0].empty())
 760             {
 761                     throw mp::filter::FilterException
 762                         ("Missing attribute, type for for element "
 763                          + std::string((const char *) ptr->name)
 764                          + " in http_rewrite filter");
 765             }
 766             Content c;
 767
 768             c.type = values[0];
 769             // if (!values[1].empty())
 770                 c.content_re = values[1];
 771             c.configure(ptr->children, rules);
 772             phase.content_list.push_back(c);
 773         }
 774         else
 775         {
 776             throw mp::filter::FilterException
 777                 ("Bad element "
 778                  + std::string((const char *) ptr->name)
 779                  + " in http_rewrite filter");
 780         }
 781     }
 782 }
 783
 784 void yf::HttpRewrite::configure(const xmlNode * ptr, bool test_only,
 785         const char *path)
 786 {
 787     for (ptr = ptr->children; ptr; ptr = ptr->next)
 788     {
 789         if (ptr->type != XML_ELEMENT_NODE)
 790             continue;
 791         else if (!strcmp((const char *) ptr->name, "request"))
 792         {
 793             configure_phase(ptr, *req_phase);
 794         }
 795         else if (!strcmp((const char *) ptr->name, "response"))
 796         {
 797             configure_phase(ptr, *res_phase);
 798         }
 799         else
 800         {
 801             throw mp::filter::FilterException
 802                 ("Bad element "
 803                  + std::string((const char *) ptr->name)
 804                  + " in http_rewrite1 filter");
 805         }
 806     }
 807 }
 808
 809 static mp::filter::Base* filter_creator()
 810 {
 811     return new mp::filter::HttpRewrite;
 812 }
 813
 814 extern "C" {
 815     struct metaproxy_1_filter_struct metaproxy_1_filter_http_rewrite = {
 816         0,
 817         "http_rewrite",
 818         filter_creator
 819     };
 820 }
 821
 822
 823 /*
 824  * Local variables:
 825  * c-basic-offset: 4
 826  * c-file-style: "Stroustrup"
 827  * indent-tabs-mode: nil
 828  * End:
 829  * vim: shiftwidth=4 tabstop=8 expandtab
 830  */
 831