src/test_filter_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 <iostream>
  21 #include <stdexcept>
  22
  23 #include "filter_http_client.hpp"
  24 #include <metaproxy/util.hpp>
  25 #include "router_chain.hpp"
  26 #include <metaproxy/package.hpp>
  27
  28 #include <boost/regex.hpp>
  29 #include <boost/lexical_cast.hpp>
  30
  31 #define BOOST_AUTO_TEST_MAIN
  32 #define BOOST_TEST_DYN_LINK
  33
  34 #include <boost/test/auto_unit_test.hpp>
  35
  36 using namespace boost::unit_test;
  37 namespace mp = metaproxy_1;
  38
  39 class FilterHeaderRewrite: public mp::filter::Base {
  40 public:
  41     void process(mp::Package & package) const {
  42         Z_GDU *gdu = package.request().get();
  43         //we have an http req
  44         if (gdu && gdu->which == Z_GDU_HTTP_Request)
  45         {
  46           std::cout << "Request headers" << std::endl;
  47           Z_HTTP_Request *hreq = gdu->u.HTTP_Request;
  48           //dump req headers
  49           for (Z_HTTP_Header *header = hreq->headers;
  50               header != 0;
  51               header = header->next)
  52           {
  53             std::cout << header->name << ": " << header->value << std::endl;
  54             rewrite_req_header(header);
  55           }
  56         }
  57         package.move();
  58         gdu = package.response().get();
  59         if (gdu && gdu->which == Z_GDU_HTTP_Response)
  60         {
  61           std::cout << "Respose headers" << std::endl;
  62           Z_HTTP_Response *hr = gdu->u.HTTP_Response;
  63           //dump resp headers
  64           for (Z_HTTP_Header *header = hr->headers;
  65               header != 0;
  66               header = header->next)
  67           {
  68             std::cout << header->name << ": " << header->value << std::endl;
  69           }
  70         }
  71
  72     };
  73     void configure(const xmlNode* ptr, bool test_only, const char *path) {};
  74
  75     void rewrite_req_header(Z_HTTP_Header *header) const
  76     {
  77         //exec regex against value
  78         boost::regex re(req_uri_rx);
  79         boost::smatch what;
  80         std::string hvalue(header->value);
  81         std::map<std::string, std::string> vars;
  82         if (regex_match(hvalue, what, re))
  83         {
  84             unsigned i;
  85             for (i = 1; i < what.size(); ++i)
  86             {
  87                 //check if the group is named
  88                 std::map<int, std::string>::const_iterator it
  89                     = groups_by_num.find(i);
  90                 if (it != groups_by_num.end())
  91                 {   //it is
  92                     std::string name = it->second;
  93                     vars[name] = what[i];
  94                 }
  95             }
  96             //rewrite the header according to the recipe
  97             std::string rvalue = sub_vars(req_uri_pat, vars);
  98             std::cout << "Rewritten '"+hvalue+"' to '"+rvalue+"'\n";
  99         }
 100         else
 101         {
 102             std::cout << "No match found in '" + hvalue + "'\n";
 103         }
 104     };
 105
 106     static void parse_groups(const std::string & str,
 107             std::map<int, std::string> & groups_bynum,
 108             std::map<std::string, int> & groups_byname)
 109     {
 110        int gnum = 0;
 111        bool esc = false;
 112        for (int i = 0; i < str.size(); ++i)
 113        {
 114            if (!esc && str[i] == '\\')
 115            {
 116                esc = true;
 117                continue;
 118            }
 119            if (!esc && str[i] == '(') //group starts
 120            {
 121                gnum++;
 122                if (i+1 < str.size() && str[i+1] == '?') //group with attrs
 123                {
 124                    i++;
 125                    if (i+1 < str.size() && str[i+1] == 'P') //optional, python
 126                        i++;
 127                    if (i+1 < str.size() && str[i+1] == '<') //named
 128                    {
 129                        i++;
 130                        std::string gname;
 131                        bool term = false;
 132                        while (++i < str.size())
 133                        {
 134                            if (str[i] == '>') { term = true; break; }
 135                            if (!isalnum(str[i]))
 136                                throw mp::filter::FilterException
 137                                    ("Only alphanumeric chars allowed, found "
 138                                     " in '"
 139                                     + str
 140                                     + "' at "
 141                                     + boost::lexical_cast<std::string>(i));
 142                            gname += str[i];
 143                        }
 144                        if (!term)
 145                            throw mp::filter::FilterException
 146                                ("Unterminated group name '" + gname
 147                                 + " in '" + str +"'");
 148                       groups_bynum[gnum] = gname;
 149                       groups_byname[gname] = gnum;
 150                       std::cout << "Found named group '" << gname
 151                           << "' at $" << gnum << std::endl;
 152                    }
 153                }
 154            }
 155            esc = false;
 156        }
 157     }
 158
 159     static std::string sub_vars (const std::string & in,
 160             const std::map<std::string, std::string> & vars)
 161     {
 162         std::string out;
 163         bool esc = false;
 164         for (int i = 0; i < in.size(); ++i)
 165         {
 166             if (!esc && in[i] == '\\')
 167             {
 168                 esc = true;
 169                 continue;
 170             }
 171             if (!esc && in[i] == '$') //var
 172             {
 173                 if (i+1 < in.size() && in[i+1] == '{') //ref prefix
 174                 {
 175                     ++i;
 176                     std::string name;
 177                     bool term = false;
 178                     while (++i < in.size())
 179                     {
 180                         if (in[i] == '}') { term = true; break; }
 181                         name += in[i];
 182                     }
 183                     if (!term) throw mp::filter::FilterException
 184                         ("Unterminated var ref in '"+in+"' at "
 185                          + boost::lexical_cast<std::string>(i));
 186                     std::map<std::string, std::string>::const_iterator it
 187                         = vars.find(name);
 188                     if (it != vars.end())
 189                         out += it->second;
 190                 }
 191                 else
 192                 {
 193                     throw mp::filter::FilterException
 194                         ("Malformed or trimmed var ref in '"
 195                          +in+"' at "+boost::lexical_cast<std::string>(i));
 196                 }
 197                 continue;
 198             }
 199             //passthru
 200             out += in[i];
 201             esc = false;
 202         }
 203         return out;
 204     }
 205
 206     void configure(
 207             const std::string & req_uri_rx,
 208             const std::string & req_uri_pat,
 209             const std::string & resp_uri_rx,
 210             const std::string & resp_uri_pat)
 211     {
 212        this->req_uri_rx = req_uri_rx;
 213        this->req_uri_pat = req_uri_pat;
 214        //pick up names
 215        parse_groups(req_uri_rx, groups_by_num, groups_by_name);
 216        this->resp_uri_rx = resp_uri_rx;
 217        this->resp_uri_pat = resp_uri_pat;
 218     };
 219
 220 private:
 221     std::map<std::string, std::string> vars;
 222     std::string req_uri_rx;
 223     std::string resp_uri_rx;
 224     std::string req_uri_pat;
 225     std::string resp_uri_pat;
 226     std::map<int, std::string> groups_by_num;
 227     std::map<std::string, int> groups_by_name;
 228
 229 };
 230
 231
 232 BOOST_AUTO_TEST_CASE( test_filter_rewrite_1 )
 233 {
 234     try
 235     {
 236        FilterHeaderRewrite fhr;
 237     }
 238     catch ( ... ) {
 239         BOOST_CHECK (false);
 240     }
 241 }
 242
 243 BOOST_AUTO_TEST_CASE( test_filter_rewrite_2 )
 244 {
 245     try
 246     {
 247         mp::RouterChain router;
 248
 249         FilterHeaderRewrite fhr;
 250         fhr.configure(
 251                 ".*?(?<host>[^:]+):(?<port>\\d+).*",
 252                 "http://${host}:${port}/somepath",
 253                 ".*(localhost).*",
 254                 "http:://g");
 255         mp::filter::HTTPClient hc;
 256
 257         router.append(fhr);
 258         router.append(hc);
 259
 260         // create an http request
 261         mp::Package pack;
 262
 263         mp::odr odr;
 264         Z_GDU *gdu_req = z_get_HTTP_Request_uri(odr,
 265             "http://localhost:80/~jakub/targetsite.php", 0, 1);
 266
 267         pack.request() = gdu_req;
 268
 269         //feed to the router
 270         pack.router(router).move();
 271
 272         //analyze the response
 273         Z_GDU *gdu_res = pack.response().get();
 274         BOOST_CHECK(gdu_res);
 275         BOOST_CHECK_EQUAL(gdu_res->which, Z_GDU_HTTP_Response);
 276
 277         Z_HTTP_Response *hres = gdu_res->u.HTTP_Response;
 278         BOOST_CHECK(hres);
 279
 280     }
 281     catch (std::exception & e) {
 282         std::cout << e.what();
 283         BOOST_CHECK (false);
 284     }
 285 }
 286
 287 /*
 288  * Local variables:
 289  * c-basic-offset: 4
 290  * c-file-style: "Stroustrup"
 291  * indent-tabs-mode: nil
 292  * End:
 293  * vim: shiftwidth=4 tabstop=8 expandtab
 294  */
 295