metaproxy  1.13.0
filter_http_client.cpp
Go to the documentation of this file.
1 /* This file is part of Metaproxy.
2  Copyright (C) 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 <yaz/url.h>
24 #include "filter_http_client.hpp"
25 
26 #include <yaz/zgdu.h>
27 #include <yaz/log.h>
28 
29 #include <boost/thread/mutex.hpp>
30 
31 #include <list>
32 #include <map>
33 #include <iostream>
34 
35 #if HAVE_SYS_TYPES_H
36 #include <sys/types.h>
37 #endif
38 
39 #if HAVE_SYS_STAT_H
40 #include <sys/stat.h>
41 #endif
42 
43 namespace mp = metaproxy_1;
44 namespace yf = mp::filter;
45 
46 namespace metaproxy_1 {
47  namespace filter {
49  friend class HTTPClient;
50  void proxy(mp::Package &package);
51  std::string proxy_host;
52  std::string default_host;
55  bool bind_host;
56  Rep();
57  };
58  }
59 }
60 
61 yf::HTTPClient::Rep::Rep()
62 {
63  max_redirects = 0;
64  x_forwarded_for = false;
65  bind_host = false;
66 }
67 
68 yf::HTTPClient::HTTPClient() : m_p(new Rep)
69 {
70 }
71 
72 yf::HTTPClient::~HTTPClient()
73 {
74 }
75 
76 void yf::HTTPClient::Rep::proxy(mp::Package &package)
77 {
78  Z_GDU *req_gdu = package.request().get();
79  if (req_gdu && req_gdu->which == Z_GDU_HTTP_Request)
80  {
81  Z_HTTP_Request *hreq = req_gdu->u.HTTP_Request;
82  Z_GDU *res_gdu = 0;
83  mp::odr o;
84  yaz_url_t yaz_url = yaz_url_create();
85  const char *http_proxy =
86  z_HTTP_header_remove(&hreq->headers, "X-Metaproxy-Proxy");
87 
88  if (!http_proxy)
89  http_proxy = proxy_host.c_str();
90 
91  if (*http_proxy)
92  yaz_url_set_proxy(yaz_url, http_proxy);
93 
94  yaz_url_set_max_redirects(yaz_url, max_redirects);
95 
96  if (x_forwarded_for)
97  {
98  std::string peer_name2 = package.origin().get_address();
99  const char *peer_name1 =
100  z_HTTP_header_lookup(hreq->headers, "X-Forwarded-For");
101  std::string pcomb;
102  if (peer_name1)
103  {
104  pcomb.append(peer_name1);
105  pcomb.append(", ");
106  }
107  pcomb.append(peer_name2);
108  z_HTTP_header_set(o, &hreq->headers, "X-Forwarded-For",
109  pcomb.c_str());
110  }
111  std::string uri;
112  if (hreq->path[0] == '/')
113  {
114  if (default_host.length())
115  uri = default_host + hreq->path;
116  }
117  else
118  uri = hreq->path;
119 
120  if (bind_host)
121  {
122  std::string host = package.origin().get_bind_address();
123  uri.append(" ");
124  uri.append(host);
125  }
126  if (!uri.length())
127  {
128  res_gdu = o.create_HTTP_Response_details(
129  package.session(),
130  hreq, 404,
131  "http_client: no target URI specified");
132  }
133  else
134  {
135  Z_HTTP_Response * http_response =
136  yaz_url_exec(yaz_url, uri.c_str(), hreq->method,
137  hreq->headers, hreq->content_buf,
138  hreq->content_len);
139  if (http_response)
140  {
141  res_gdu = o.create_HTTP_Response(package.session(), hreq, 200);
142  z_HTTP_header_remove(&http_response->headers, "Transfer-Encoding");
143  res_gdu->u.HTTP_Response = http_response;
144  }
145  else
146  {
147  res_gdu = o.create_HTTP_Response_details(
148  package.session(),
149  hreq, 502, yaz_url_get_error(yaz_url));
150  }
151  }
152  package.response() = res_gdu;
153  yaz_url_destroy(yaz_url);
154  }
155  else
156  package.move();
157 }
158 
159 void yf::HTTPClient::process(mp::Package &package) const
160 {
161  Z_GDU *gdu = package.request().get();
162  if (gdu && gdu->which == Z_GDU_HTTP_Request)
163  m_p->proxy(package);
164  else
165  package.move();
166 }
167 
168 void mp::filter::HTTPClient::configure(const xmlNode * ptr, bool test_only,
169  const char *path)
170 {
171  for (ptr = ptr->children; ptr; ptr = ptr->next)
172  {
173  if (ptr->type != XML_ELEMENT_NODE)
174  continue;
175  else if (!strcmp((const char *) ptr->name, "proxy"))
176  {
177  m_p->proxy_host = mp::xml::get_text(ptr);
178  }
179  else if (!strcmp((const char *) ptr->name, "max-redirects"))
180  {
181  m_p->max_redirects = mp::xml::get_int(ptr, 0);
182  }
183  else if (!strcmp((const char *) ptr->name, "default-host"))
184  {
185  m_p->default_host = mp::xml::get_text(ptr);
186  if (m_p->default_host.find("://") == std::string::npos)
187  {
188  throw mp::filter::FilterException
189  ("default-host is missing method (such as http://)"
190  " in http_client filter");
191  }
192  }
193  else if (!strcmp((const char *) ptr->name, "x-forwarded-for"))
194  {
195  m_p->x_forwarded_for = mp::xml::get_bool(ptr, 0);
196  }
197  else if (!strcmp((const char *) ptr->name, "bind_host"))
198  {
199  m_p->bind_host = mp::xml::get_bool(ptr, 0);
200  }
201  else
202  {
203  throw mp::filter::FilterException
204  ("Bad element "
205  + std::string((const char *) ptr->name)
206  + " in http_client filter");
207  }
208  }
209 }
210 
211 static mp::filter::Base* filter_creator()
212 {
213  return new mp::filter::HTTPClient;
214 }
215 
216 extern "C" {
217  struct metaproxy_1_filter_struct metaproxy_1_filter_http_client = {
218  0,
219  "http_client",
221  };
222 }
223 
224 
225 /*
226  * Local variables:
227  * c-basic-offset: 4
228  * c-file-style: "Stroustrup"
229  * indent-tabs-mode: nil
230  * End:
231  * vim: shiftwidth=4 tabstop=8 expandtab
232  */
233 
void proxy(mp::Package &package)
struct metaproxy_1_filter_struct metaproxy_1_filter_http_client
static mp::filter::Base * filter_creator()