Implement package search service mockup

27 files changed, 637 insertions, 545 deletions

diff --git a/brep/buildfile b/brep/buildfile
index 5340d22..9b64ed4 100644
--- a/brep/buildfile
+++ b/brep/buildfile
@@ -6,20 +6,36 @@ using cli
 
 .: libso{brep brep-apache}
 
-import libs += libbpkg%lib{bpkg}
-import libs += libodb-pgsql%lib{odb-pgsql}
+# brep library build rules.
+#
 import libs += libodb%lib{odb}
+import libs += libodb-pgsql%lib{odb-pgsql}
+import libs += libbpkg%lib{bpkg}
 
 brep = cxx{package package-odb}
+
 libso{brep}: $brep $libs
 libso{brep}: cxx.export.poptions = -I$out_root -I$src_root
 
-brep = cxx{diagnostics module services search view shared-database} \
-       cli.cxx{options}
-web = ../web/apache/cxx{request service}
+# brep-apache library build rules.
+#
+import libs += libstudxml%lib{studxml}
+
+brep = cxx{diagnostics module services package-search package-version-search \
+       shared-database} cli.cxx{options}
+web = ../web/apache/cxx{request service} ../web/cxx{mime-url-encoding}
+
 libso{brep-apache}: $brep $web libso{brep} $libs
 
+# Set option prefix to the empty value to handle all unknown request parameters
+# uniformly with a single catch block.
+#
+# @@ Adding --option-prefix "" leads to appearing the following warnings
+#    related to options _parse methed:
+# brep/options.cxx:663:33: warning: unused parameter ‘opt_mode’ [-Wunused-parameter]
+#             ::cli::unknown_mode opt_mode,
+#
 cli.options += -I $src_root --include-with-brackets --include-prefix brep \
---guard-prefix BREP --generate-file-scanner --suppress-usage
+--guard-prefix BREP --generate-file-scanner --suppress-usage --option-prefix ""
 
 cli.cxx{options}: cli{options}
diff --git a/brep/module b/brep/module
index 08fbfea..0743598 100644
--- a/brep/module
+++ b/brep/module
@@ -92,6 +92,8 @@ namespace brep
     module ();
     module (const module& );
 
+    // Can be used by module implementation to parse HTTP request parameters.
+    //
     class param_scanner: public cli::scanner
     {
     public:
diff --git a/brep/module.cxx b/brep/module.cxx
index c52d13a..62c70c9 100644
--- a/brep/module.cxx
+++ b/brep/module.cxx
@@ -22,6 +22,7 @@
 
 using namespace std;
 using namespace placeholders; // For std::bind's _1, etc.
+using namespace cli;
 
 namespace brep
 {
@@ -98,22 +99,22 @@ namespace brep
       {
         // Read module implementation configuration.
         //
-        cli::argv_file_scanner s (0,
-                                  argc,
-                                  const_cast<char**> (argv.data ()),
-                                  "conf");
+        argv_file_scanner s (0,
+                             argc,
+                             const_cast<char**> (argv.data ()),
+                             "conf");
 
         init (s);
       }
 
       // Read brep::module configuration.
       //
-      cli::argv_file_scanner s (0,
-                                argc,
-                                const_cast<char**> (argv.data ()),
-                                "conf");
+      argv_file_scanner s (0,
+                           argc,
+                           const_cast<char**> (argv.data ()),
+                           "conf");
 
-      options::module o (s, cli::unknown_mode::skip, cli::unknown_mode::skip);
+      options::module o (s, unknown_mode::skip, unknown_mode::skip);
       verb_ = o.verb ();
     }
     catch (const server_error& e)
@@ -253,7 +254,7 @@ namespace brep
     if (i_ != name_values_.end ())
       return name_ ? i_->name.c_str () : i_->value.c_str ();
     else
-      throw cli::eos_reached ();
+      throw eos_reached ();
   }
 
   const char* module::param_scanner::
@@ -270,7 +271,7 @@ namespace brep
       return r;
     }
     else
-      throw cli::eos_reached ();
+      throw eos_reached ();
   }
 
   void module::param_scanner::
@@ -284,6 +285,6 @@ namespace brep
       name_ = !name_;
     }
     else
-      throw cli::eos_reached ();
+      throw eos_reached ();
   }
 }
diff --git a/brep/options.cli b/brep/options.cli
index 2894979..8062f59 100644
--- a/brep/options.cli
+++ b/brep/options.cli
@@ -3,7 +3,7 @@
 // license   : MIT; see accompanying LICENSE file
 
 include <string>;
-include <cstdint>;
+include <cstdint>; // uint16_t
 
 namespace brep
 {
@@ -22,23 +22,43 @@ namespace brep
       std::uint16_t db-port = 5432;
     };
 
-    class search: module, db
+    class package_search: module, db
     {
-      size_t results-on-page = 10;
+      std::uint16_t results-on-page = 10;
     };
 
-    class view: module, db
+    class package_version_search: module, db
     {
+      std::uint16_t results-on-page = 10;
     };
   }
 
-  // Web module request parameters.
+  // Web module HTTP request parameters.
   //
   namespace params
   {
-    class search
+    // Use parameters long names in the C++ code, short aliases in HTTP URL.
+    //
+    class package_search
     {
-      size_t page = 0;
+      // Display package search result list starting from this page.
+      //
+      std::uint16_t page | p = 0;
+
+      // Package search criteria.
+      //
+      std::string query | q = "";
+    };
+
+    class package_version_search
+    {
+      // Display package version search result list starting from this page.
+      //
+      std::uint16_t page | p = 0;
+
+      // Package version search criteria.
+      //
+      std::string query | q = "";
     };
   }
 }
diff --git a/brep/search b/brep/package-search
index 0283859..156ed68 100644
--- a/brep/search
+++ b/brep/package-search
@@ -1,20 +1,20 @@
-// file      : brep/search -*- C++ -*-
+// file      : brep/package-search -*- C++ -*-
 // copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#ifndef BREP_SEARCH
-#define BREP_SEARCH
+#ifndef BREP_PACKAGE_SEARCH
+#define BREP_PACKAGE_SEARCH
 
 #include <memory> // shared_ptr
 
-#include <odb/database.hxx>
+#include <odb/forward.hxx> // database
 
 #include <brep/module>
 #include <brep/options>
 
 namespace brep
 {
-  class search: public module
+  class package_search: public module
   {
   private:
     virtual void
@@ -24,9 +24,9 @@ namespace brep
     init (cli::scanner&);
 
   private:
-    std::shared_ptr<options::search> options_;
+    std::shared_ptr<options::package_search> options_;
     std::shared_ptr<odb::core::database> db_;
   };
 }
 
-#endif // BREP_SEARCH
+#endif // BREP_PACKAGE_SEARCH
diff --git a/brep/package-search.cxx b/brep/package-search.cxx
new file mode 100644
index 0000000..3317d43
--- /dev/null
+++ b/brep/package-search.cxx
@@ -0,0 +1,154 @@
+// file      : brep/package-search.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <brep/package-search>
+
+#include <string>
+#include <memory> // make_shared()
+
+#include <xml/serializer>
+
+#include <odb/database.hxx>
+#include <odb/transaction.hxx>
+
+#include <web/xhtml>
+#include <web/module>
+#include <web/mime-url-encoding>
+
+#include <brep/package>
+#include <brep/package-odb>
+#include <brep/shared-database>
+
+using namespace std;
+using namespace cli;
+using namespace odb::core;
+
+namespace brep
+{
+  void package_search::
+  init (scanner& s)
+  {
+    MODULE_DIAG;
+
+    options_ = make_shared<options::package_search> (
+      s, unknown_mode::fail, unknown_mode::fail);
+
+    db_ = shared_database (options_->db_host (), options_->db_port ());
+  }
+
+  void package_search::
+  handle (request& rq, response& rs)
+  {
+    using namespace xml;
+    using namespace web;
+    using namespace web::xhtml;
+
+    MODULE_DIAG;
+
+    params::package_search pr;
+
+    try
+    {
+      param_scanner s (rq.parameters ());
+      pr = params::package_search (s, unknown_mode::fail, unknown_mode::fail);
+    }
+    catch (const unknown_argument& e)
+    {
+      throw invalid_request (400, e.what ());
+    }
+
+    // @@ Would be nice to have a manipulator identing string properly
+    //    according to the most nested element identation.
+    //
+    const char* ident ("\n      ");
+    const char* title ("Package Search");
+    serializer s (rs.content (), title);
+
+    s << HTML
+      <<   HEAD
+      <<     TITLE << title << ~TITLE
+      <<     STYLE(TYPE="text/css") << ident
+      <<     ".package {margin: 0 0 0.5em;}" << ident
+      <<     ".name a {text-decoration: none;}" << ident
+      <<     ".summary {font-size: small;}"
+      <<     ~STYLE
+      <<   ~HEAD
+      <<   BODY;
+
+    string q (
+      pr.query ().empty () ? "" : "q=" + mime_url_encode (pr.query ()));
+
+    transaction t (db_->begin ());
+
+    // @@ Use appropriate view when clarify which package info to be displayed
+    //    and search index structure get implemented.
+    //
+    using query = query<package>;
+    auto r (
+      db_->query<package> (
+        "ORDER BY" + query::name +
+        "OFFSET" + to_string (pr.page () * options_->results_on_page ()) +
+        "LIMIT" + to_string (options_->results_on_page ())));
+
+    for (const auto& p: r)
+    {
+      s <<   DIV(CLASS="package")
+        <<     DIV(CLASS="name")
+        <<       A
+        <<         HREF
+        <<           "/go/" << mime_url_encode (p.name);
+
+      // Propagate search criteria to the package version search url.
+      //
+      if (!q.empty ())
+        s <<         "?" << q;
+
+      s <<         ~HREF
+        <<         p.name
+        <<       ~A
+        <<     ~DIV
+        <<     DIV(CLASS="summary")
+        <<       p.summary
+        <<     ~DIV
+        <<   ~DIV;
+    }
+
+    t.commit ();
+
+    if (pr.page () || r.size () == options_->results_on_page ())
+    {
+      s <<   DIV;
+
+      if (pr.page ())
+      {
+        s <<   A
+          <<     HREF << "/?p=" << pr.page () - 1
+          <<             (q.empty () ? "" : "&" + q)
+          <<     ~HREF
+          <<     "Previous"
+          <<   ~A
+          <<   " ";
+      }
+
+      // @@ Not ideal as can produce link to an empty page, but easy to fix
+      //    and most likelly will be replaced with something more meaningful
+      //    based on knowing the total number of matched packages.
+      //
+      if (r.size () == options_->results_on_page ())
+      {
+        s <<   A
+          <<     HREF << "/?p=" << pr.page () + 1
+          <<             (q.empty () ? "" : "&" + q)
+          <<     ~HREF
+          <<     "Next"
+          <<   ~A;
+      }
+
+      s <<   ~DIV;
+    }
+
+    s <<   ~BODY
+      << ~HTML;
+  }
+}
diff --git a/brep/view b/brep/package-version-search
index 280b9ab..0292ae0 100644
--- a/brep/view
+++ b/brep/package-version-search
@@ -1,20 +1,20 @@
-// file      : brep/view -*- C++ -*-
+// file      : brep/package-version-search -*- C++ -*-
 // copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#ifndef BREP_VIEW
-#define BREP_VIEW
+#ifndef BREP_PACKAGE_VERSION_SEARCH
+#define BREP_PACKAGE_VERSION_SEARCH
 
 #include <memory> // shared_ptr
 
-#include <odb/database.hxx>
+#include <odb/forward.hxx> // database
 
 #include <brep/module>
 #include <brep/options>
 
 namespace brep
 {
-  class view: public module
+  class package_version_search: public module
   {
   private:
     virtual void
@@ -24,9 +24,9 @@ namespace brep
     init (cli::scanner&);
 
   private:
-    std::shared_ptr<options::view> options_;
+    std::shared_ptr<options::package_version_search> options_;
     std::shared_ptr<odb::core::database> db_;
   };
 }
 
-#endif // BREP_VIEW
+#endif // BREP_PACKAGE_VERSION_SEARCH
diff --git a/brep/package-version-search.cxx b/brep/package-version-search.cxx
new file mode 100644
index 0000000..a989434
--- /dev/null
+++ b/brep/package-version-search.cxx
@@ -0,0 +1,73 @@
+// file      : brep/package-version-search.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <brep/package-version-search>
+
+#include <string>
+#include <memory> // make_shared()
+
+#include <xml/serializer>
+
+#include <odb/database.hxx>
+#include <odb/transaction.hxx>
+
+#include <web/xhtml>
+#include <web/module>
+#include <web/mime-url-encoding>
+
+#include <brep/package>
+#include <brep/package-odb>
+#include <brep/shared-database>
+
+using namespace std;
+using namespace cli;
+using namespace odb::core;
+
+namespace brep
+{
+  void package_version_search::
+  init (scanner& s)
+  {
+    MODULE_DIAG;
+
+    options_ = make_shared<options::package_version_search> (
+      s, unknown_mode::fail, unknown_mode::fail);
+
+    db_ = shared_database (options_->db_host (), options_->db_port ());
+  }
+
+  void package_version_search::
+  handle (request& rq, response& rs)
+  {
+    using namespace xml;
+    using namespace web;
+    using namespace web::xhtml;
+
+    MODULE_DIAG;
+
+    const string& name (*rq.path ().rbegin ());
+    params::package_version_search pr;
+
+    try
+    {
+      param_scanner s (rq.parameters ());
+      pr = params::package_version_search (
+        s, unknown_mode::fail, unknown_mode::fail);
+    }
+    catch (const unknown_argument& e)
+    {
+      throw invalid_request (400, e.what ());
+    }
+
+    const char* title ("Package");
+    serializer s (rs.content (), title);
+
+    s << HTML
+      <<   HEAD
+      <<     TITLE << title << ~TITLE
+      <<   ~HEAD
+      <<   BODY << name << ~BODY
+      << ~HTML;
+  }
+}
diff --git a/brep/search.cxx b/brep/search.cxx
deleted file mode 100644
index 9185aa5..0000000
--- a/brep/search.cxx
+++ /dev/null
@@ -1,169 +0,0 @@
-// file      : brep/search.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <brep/search>
-
-#include <memory> // shared_ptr, make_shared()
-#include <chrono>
-#include <ostream>
-
-#include <odb/session.hxx>
-#include <odb/database.hxx>
-#include <odb/transaction.hxx>
-
-#include <butl/path>
-
-#include <web/module>
-
-#include <brep/package>
-#include <brep/package-odb>
-#include <brep/shared-database>
-
-using namespace std;
-using namespace odb::core;
-
-namespace brep
-{
-  void search::
-  init (cli::scanner& s)
-  {
-    MODULE_DIAG;
-
-    options_ = make_shared<options::search> (s,
-                                             cli::unknown_mode::fail,
-                                             cli::unknown_mode::fail);
-
-    db_ = shared_database (options_->db_host (), options_->db_port ());
-
-    if (options_->results_on_page () > 30)
-      fail << "too many search results on page: "
-           << options_->results_on_page ();
-    else if (options_->results_on_page () > 10)
-      warn << options_->results_on_page ()
-           << " search results on page is quite a lot but will try to cope";
-  }
-
-  void search::
-  handle (request& rq, response& rs)
-  {
-    MODULE_DIAG;
-
-    shared_ptr<package> cli (
-      make_shared<package> ("cli",
-                            "CLI is ...",
-                            strings ({"compiler", "c++"}),
-                            string ("This is CLI"),
-                            url (),
-                            url (),
-                            email (),
-                            email ()));
-
-    shared_ptr<repository> stable (
-      make_shared<repository> (
-        repository_location ("http://pkg.cpp.org/1/stable"),
-        "Stable",
-        dir_path ("/var/pkg/1/stable")));
-
-    licenses l;
-    l.comment = "License\"A'";
-    l.push_back ("XXX");
-    l.push_back ("AAA");
-    l.push_back ("BBB");
-    l.push_back ("CCC");
-
-    dependency_alternatives da;
-    da.push_back (
-      {"icl", version_comparison{version ("1.3.3"),  comparison::gt}});
-
-    da.push_back (
-      {"ocl", version_comparison{version ("1.5.5"),  comparison::lt}});
-
-    requirement_alternatives ra1;
-    ra1.push_back ("TAO");
-    ra1.push_back ("ORBacus");
-
-    requirement_alternatives ra2;
-    ra2.push_back ("Xerces");
-
-    shared_ptr<package_version> v (
-      make_shared<package_version> (stable,
-                                    cli,
-                                    version ("1.1"),
-                                    priority (),
-                                    license_alternatives ({l}),
-                                    "some changes 1\nsome changes 2",
-                                    dependencies ({da}),
-                                    requirements ({ra1, ra2})));
-
-    transaction t (db_->begin ());
-//    t.tracer (odb::stderr_full_tracer);
-
-    {
-      db_->persist (cli);
-      db_->persist (stable);
-      db_->persist (v);
-    }
-
-    t.commit ();
-
-    chrono::seconds ma (60);
-    rs.cookie ("Oh", " Ah\n\n", &ma, "/");
-    rs.cookie ("Hm", ";Yes", &ma);
-
-    info << "handling search request from "; // << rq.client_ip ();
-
-    ostream& o (rs.content ());
-
-    o << "<html><head></head><body>";
-
-    o << "<b>Options:</b>"
-      << "<br>\ntracing verbosity: " << options_->verb ()
-      << "<br>\ndb endpoint: " << options_->db_host () << ":"
-      << options_->db_port ()
-      << "<br>\nsearch results on page: " << options_->results_on_page ();
-
-    o << "<p>\n<b>Params:</b>";
-
-    const name_values& ps (rq.parameters ());
-
-    if (ps.empty ())
-      throw invalid_request (422, "search parameters expected");
-
-    if (ps.size () > 100)
-      fail << "too many parameters: " << ps.size () <<
-        info << "are you crazy to specify so many?";
-
-    level2 ([&]{trace << "search request with " << ps.size () << " params";});
-
-    for (const auto& p: ps)
-    {
-      o << "<br>\n" << p.name << "=" << p.value;
-    }
-
-    param_scanner s (ps);
-    unique_ptr<params::search> prm;
-
-    try
-    {
-      prm.reset (new params::search (s,
-                                     cli::unknown_mode::fail,
-                                     cli::unknown_mode::fail));
-    }
-    catch (const cli::unknown_argument& e)
-    {
-      throw invalid_request (400, e.what ());
-    }
-
-    o << "<br>\nPage num: " << prm->page ();
-    o << "<p>\n<b>Cookies:</b>";
-
-    for (const auto& c: rq.cookies ())
-    {
-      o << "<br>\n" << c.name << "=" << c.value;
-    }
-
-    o << "<p><a href='view'>View</a>"
-      << "</body></html>";
-  }
-}
diff --git a/brep/services.cxx b/brep/services.cxx
index 86b27b7..510a231 100644
--- a/brep/services.cxx
+++ b/brep/services.cxx
@@ -1,21 +1,25 @@
-// file      : services.cxx -*- C++ -*-
+// file      : brep/services.cxx -*- C++ -*-
 // copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
 // license   : MIT; see accompanying LICENSE file
 
-#include <brep/view>
-#include <brep/search>
+#include <ap_config.h> // AP_MODULE_DECLARE_DATA
 
 #include <web/apache/service>
 
+#include <brep/package-search>
+#include <brep/package-version-search>
+
 using namespace brep;
 using web::apache::service;
 
-static search search_mod;
-service AP_MODULE_DECLARE_DATA search_srv ("search",
-                                           search_mod,
-                                           {"db-host", "db-port", "conf"});
+static package_search package_search_mod;
+service AP_MODULE_DECLARE_DATA package_search_srv (
+  "package-search",
+  package_search_mod,
+  {"db-host", "db-port", "conf"});
 
-static view view_mod;
-service AP_MODULE_DECLARE_DATA view_srv ("view",
-                                         view_mod,
-                                         {"db-host", "db-port", "conf"});
+static package_version_search package_version_search_mod;
+service AP_MODULE_DECLARE_DATA package_version_search_srv (
+  "package-version-search",
+  package_version_search_mod,
+  {"db-host", "db-port", "conf"});
diff --git a/brep/shared-database b/brep/shared-database
index cad526f..36fa0a2 100644
--- a/brep/shared-database
+++ b/brep/shared-database
@@ -14,8 +14,8 @@ namespace brep
 {
   // Returns pointer to the shared database instance, creating one on the
   // first call. On subsequent calls ensures passed host and port equals
-  // to ones of the shared database instance throwing runtime_error otherwise.
-  // Is not thread-safe.
+  // to ones of the existing database instance throwing runtime_error
+  // otherwise. Is not thread-safe.
   //
   std::shared_ptr<odb::core::database>
   shared_database (const std::string& host, unsigned int port);
diff --git a/brep/shared-database.cxx b/brep/shared-database.cxx
index fb952d8..fc17659 100644
--- a/brep/shared-database.cxx
+++ b/brep/shared-database.cxx
@@ -10,14 +10,14 @@
 #include <odb/pgsql/database.hxx>
 
 using namespace std;
-using namespace odb;
 
 namespace brep
 {
-  shared_ptr<database>
-  shared_database (const string& host, unsigned int port)
+  shared_ptr<odb::database>
+  shared_database (const string& h, unsigned int p)
   {
-    static weak_ptr<pgsql::database> db;
+    using odb::pgsql::database;
+    static weak_ptr<database> db;
 
     // In C++11, function-static variable initialization is
     // guaranteed to be thread-safe, thought this doesn't
diff --git a/brep/view.cxx b/brep/view.cxx
deleted file mode 100644
index 3098e93..0000000
--- a/brep/view.cxx
+++ /dev/null
@@ -1,131 +0,0 @@
-// file      : brep/view.cxx -*- C++ -*-
-// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
-// license   : MIT; see accompanying LICENSE file
-
-#include <brep/view>
-
-#include <memory> // shared_ptr, make_shared()
-#include <ostream>
-
-#include <odb/session.hxx>
-#include <odb/database.hxx>
-#include <odb/transaction.hxx>
-
-#include <web/module>
-
-#include <brep/package>
-#include <brep/package-odb>
-#include <brep/shared-database>
-
-using namespace std;
-using namespace odb::core;
-
-#pragma db namespace session
-namespace brep
-{
-  void view::
-  init (cli::scanner& s)
-  {
-    options_ = make_shared<options::view> (s,
-                                           cli::unknown_mode::fail,
-                                           cli::unknown_mode::fail);
-
-    db_ = shared_database (options_->db_host (), options_->db_port ());
-  }
-
-  void view::
-  handle (request& rq, response& rs)
-  {
-    session s;
-    transaction t (db_->begin ());
-
-    shared_ptr<package> p (db_->load<package> ("cli"));
-
-    for (auto& vp: p->versions)
-    {
-      shared_ptr<package_version> v (vp.load ());
-      v->repository.load ();
-      v->package.load ();
-    }
-
-    t.commit ();
-
-    ostream& o (rs.content (200, "text/html;charset=utf-8", false));
-
-    o << "<html><head></head><body>";
-
-    o << "<b>Options:</b>"
-      << "<br>\ntracing verbosity: " << options_->verb ()
-      << "<br>\ndb endpoint: " << options_->db_host () << ":"
-      << options_->db_port ();
-
-    o << "<p>\n<b>Cookies:</b>";
-
-    for (const auto& c: rq.cookies ())
-    {
-      o << "<br>\n" << c.name << "=" << c.value;
-    }
-
-    o << "<p>\n" << p->name << ": " << p->versions.size ();
-
-    for (const auto& vp: p->versions)
-    {
-      // Just finds package_version object in session cache.
-      //
-      shared_ptr<package_version> v (vp.load ());
-
-      assert (v != nullptr);
-      assert (v->repository.get_eager () != nullptr);
-      assert (v->package.get_eager () != nullptr);
-
-      o << "<br>version:" << v->version.string ()
-        << "<br>package:" << v->package->name
-        << "<br>repo:" << v->repository->display_name
-        << "<br>changes:" << v->changes
-        << "<br>licenses:" << v->license_alternatives.size ();
-
-      for (const auto& la: v->license_alternatives)
-      {
-        o << "<br>";
-
-        for (const auto& l: la)
-        {
-          o << " |" << l << "|";
-        }
-      }
-
-      o << "<br>deps:" << v->dependencies.size ();
-
-      for (const auto& da: v->dependencies)
-      {
-        o << "<br>";
-
-        for (const auto& d: da)
-        {
-          o << " |" << d.package;
-
-          if (d.version)
-          {
-            o << "," << d.version->value.string () << ","
-              << static_cast<int> (d.version->operation) << "|";
-          }
-        }
-      }
-
-      o << "<br>requirements:" << v->requirements.size ();
-
-      for (const auto& ra: v->requirements)
-      {
-        o << "<br>";
-
-        for (const auto& r: ra)
-        {
-          o << " |" << r << "|";
-        }
-      }
-    }
-
-    o << "<p><a href='search?a=1&b&c=2&d=&&x=a+b'>Search</a>"
-      << "</body></html>";
-  }
-}
diff --git a/build.sh b/build.sh
index 3d06a80..ae71e72 100755
--- a/build.sh
+++ b/build.sh
@@ -25,16 +25,19 @@ g++ -shared $DEBUG -std=c++11 -I.. -I../../libbpkg \
 echo "cli brep-apache options"
 
 cli --include-with-brackets --include-prefix brep  --hxx-suffix "" \
-    --guard-prefix BREP --generate-file-scanner --suppress-usage ./options.cli
+    --guard-prefix BREP --generate-file-scanner --suppress-usage \
+    --option-prefix "" ./options.cli
 
 echo "g++ libbrep-apache.so"
 
-s="search.cxx view.cxx module.cxx diagnostics.cxx services.cxx options.cxx \
-shared-database.cxx ../web/apache/request.cxx ../web/apache/service.cxx"
+s="package-search.cxx package-version-search.cxx module.cxx diagnostics.cxx \
+services.cxx options.cxx shared-database.cxx \
+../web/apache/request.cxx ../web/apache/service.cxx \
+../web/mime-url-encoding.cxx"
 
 g++ -shared $DEBUG -std=c++11 -I. -I/usr/include/apr-1 -I/usr/include/httpd \
     -I.. -I../../libbpkg -I../../libbutl -L. -L../../libbpkg/bpkg \
-    -fPIC -o libbrep-apache.so $s -lbrep -lbpkg -lodb-pgsql -lodb
+    -fPIC -o libbrep-apache.so $s -lbrep -lbpkg -lodb-pgsql -lodb -lstudxml
 
 cd ../loader
 
diff --git a/etc/httpd.conf b/etc/httpd.conf
index 71ac903..ef8cb50 100644
--- a/etc/httpd.conf
+++ b/etc/httpd.conf
@@ -40,30 +40,33 @@ LoadModule authz_host_module /usr/lib64/httpd/modules/mod_authz_host.so
 LoadModule expires_module /usr/lib64/httpd/modules/mod_expires.so
 LoadModule dir_module /usr/lib64/httpd/modules/mod_dir.so
 
-LoadModule search_srv ${AP_MODULE_DIR}/libbrep-apache.so
+LoadModule package_search_srv ${AP_MODULE_DIR}/libbrep-apache.so
 
-<IfModule search_srv>
-  search-db-host ${AP_DB_HOST}
-  search-db-port ${AP_DB_PORT}
-  search-conf "${AP_CONFIG_DIR}/search.conf"
+<IfModule package_search_srv>
+  package-search-db-host ${AP_DB_HOST}
+  package-search-db-port ${AP_DB_PORT}
+  package-search-conf "${AP_CONFIG_DIR}/package-search.conf"
 </IfModule>
 
-LoadModule view_srv ${AP_MODULE_DIR}/libbrep-apache.so
+LoadModule package_version_search_srv ${AP_MODULE_DIR}/libbrep-apache.so
 
-<IfModule view_srv>
-  view-db-host ${AP_DB_HOST}
-  view-db-port ${AP_DB_PORT}
-  view-conf "${AP_CONFIG_DIR}/view.conf"
+<IfModule package_version_search_srv>
+  package-version-search-db-host ${AP_DB_HOST}
+  package-version-search-db-port ${AP_DB_PORT}
+  package-version-search-conf "${AP_CONFIG_DIR}/package-version-search.conf"
 </IfModule>
 
-<LocationMatch ^/search$>
-  SetHandler search
+<LocationMatch ^/$>
+  SetHandler package-search
 </LocationMatch>
 
-<LocationMatch ^/view$>
-  SetHandler view
+<LocationMatch ^/go/[^/]+$>
+  SetHandler package-version-search
 </LocationMatch>
 
+# Location for package version details url
+#<LocationMatch ^/go/[^/]+/[^/]+$>
+
 ExtendedStatus On
 
 <Location /server-status>
@@ -81,3 +84,4 @@ ExtendedStatus On
 
 DirectoryIndex index.html
 TypesConfig /etc/mime.types
+AddOutputFilterByType DEFLATE application/xhtml+xml
diff --git a/etc/package-search.conf b/etc/package-search.conf
new file mode 100644
index 0000000..f7eb07c
--- /dev/null
+++ b/etc/package-search.conf
@@ -0,0 +1,11 @@
+# file      : etc/package-search.conf
+# copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+# license   : MIT; see accompanying LICENSE file
+#
+# brep::module options
+#
+verb 1
+
+# brep::package_search options
+#
+results-on-page 2
diff --git a/etc/package-version-search.conf b/etc/package-version-search.conf
new file mode 100644
index 0000000..aa69170
--- /dev/null
+++ b/etc/package-version-search.conf
@@ -0,0 +1,11 @@
+# file      : etc/package-version-search.conf
+# copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+# license   : MIT; see accompanying LICENSE file
+#
+# brep::module options
+#
+verb 1
+
+# brep::package_version_search options
+#
+results-on-page 10
diff --git a/etc/search.conf b/etc/search.conf
deleted file mode 100644
index be86098..0000000
--- a/etc/search.conf
+++ /dev/null
@@ -1,8 +0,0 @@
-# brep::module options
-
-verb 1
-
-# brep::search options
-
-#ah 7
-results-on-page 20
diff --git a/etc/view.conf b/etc/view.conf
deleted file mode 100644
index 7c9b163..0000000
--- a/etc/view.conf
+++ /dev/null
@@ -1,5 +0,0 @@
-# brep::module options
-
-verb 2
-
-#oh 8
diff --git a/tests/web/xhtml/driver.cxx b/tests/web/xhtml/driver.cxx
index 23531f7..9f393fd 100644
--- a/tests/web/xhtml/driver.cxx
+++ b/tests/web/xhtml/driver.cxx
@@ -3,6 +3,7 @@
 // license   : MIT; see accompanying LICENSE file
 
 #include <iostream>
+#include <functional>
 
 #include <xml/serializer>
 
@@ -11,11 +12,38 @@
 using namespace std;
 using namespace xml;
 
+static bool
+bad_sequence (const function<void(serializer& s)>& f)
+{
+  ostringstream o;
+  serializer s (o, "osstream");
+
+  try
+  {
+    f (s);
+    return false;
+  }
+  catch (const serialization&)
+  {
+    return true;
+  }
+}
+
 int
 main ()
 {
   using namespace web::xhtml;
 
+  assert (bad_sequence ([](serializer& s) {s << HTML << ~HEAD;}));
+  assert (bad_sequence ([](serializer& s) {s << HTML << DIV << ~P << ~HTML;}));
+  assert (bad_sequence ([](serializer& s) {s << HTML << DIV << ~A << ~HTML;}));
+  assert (bad_sequence ([](serializer& s) {s << P << A << "a" << ~P << ~P;}));
+  assert (bad_sequence ([](serializer& s) {s << P << A << "a" << ~I << ~P;}));
+
+  assert (
+    bad_sequence (
+      [](serializer& s) {s << P << A << ID << "A" << ~HREF << ~A << ~P;}));
+
   serializer s (cout, "output");
 
   s << HTML
diff --git a/web/apache/request b/web/apache/request
index 59d4600..88b38a9 100644
--- a/web/apache/request
+++ b/web/apache/request
@@ -43,6 +43,11 @@ namespace web
       int
       flush ();
 
+      // Get request path.
+      //
+      virtual const path_type&
+      path ();
+
       // Get request body data stream.
       //
       virtual std::istream&
@@ -93,12 +98,6 @@ namespace web
       void
       parse_parameters (const char* args);
 
-      static void
-      mime_url_encode (const char* v, std::ostream& o);
-
-      static std::string
-      mime_url_decode (const char* b, const char* e, bool trim = false);
-
       bool
       get_write_state () const noexcept {return write_state_;}
 
@@ -129,6 +128,7 @@ namespace web
       std::unique_ptr<std::ostream> out_;
       std::unique_ptr<std::streambuf> in_buf_;
       std::unique_ptr<std::istream> in_;
+      path_type path_;
       std::unique_ptr<name_values> parameters_;
       std::unique_ptr<name_values> cookies_;
       std::unique_ptr<std::string> form_data_;
diff --git a/web/apache/request.cxx b/web/apache/request.cxx
index 7727b35..497d2d6 100644
--- a/web/apache/request.cxx
+++ b/web/apache/request.cxx
@@ -14,18 +14,20 @@
 #include <memory>    // unique_ptr
 #include <sstream>
 #include <ostream>
+#include <istream>
 #include <cstring>
 #include <utility>   // move()
 #include <stdexcept>
 #include <streambuf>
 
+#include <web/mime-url-encoding>
+
 using namespace std;
 
 namespace web
 {
   namespace apache
   {
-
     istream& request::
     content ()
     {
@@ -46,10 +48,25 @@ namespace web
       return *in_;
     }
 
+    const path& request::
+    path ()
+    {
+      if (path_.empty ())
+      {
+        path_ = path_type (rec_->uri);
+
+        // Module request handler can not be called if URI is empty.
+        //
+        assert (!path_.empty ());
+      }
+
+      return path_;
+    }
+
     const name_values& request::
     parameters ()
     {
-      if (!parameters_)
+      if (parameters_ == nullptr)
       {
         parameters_.reset (new name_values ());
 
@@ -70,7 +87,7 @@ namespace web
     const name_values& request::
     cookies ()
     {
-      if (!cookies_)
+      if (cookies_ == nullptr)
       {
         cookies_.reset (new name_values ());
 
@@ -264,107 +281,5 @@ namespace web
         n = e ? e + 1 : 0;
       }
     }
-
-    void request::
-    mime_url_encode (const char* v, ostream& o)
-    {
-      char f (o.fill ());
-      ios_base::fmtflags g (o.flags ());
-      o << hex << uppercase << right << setfill ('0');
-
-      char c;
-
-      while ((c = *v++) != '\0')
-      {
-        if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') ||
-            (c >= '0' && c <= '9'))
-        {
-          o << c;
-        }
-        else
-          switch (c)
-          {
-          case ' ': o << '+'; break;
-          case '.':
-          case '_':
-          case '-':
-          case '~': o << c; break;
-          default:
-            {
-              o << "%" << setw (2) << static_cast<unsigned short> (c);
-              break;
-            }
-          }
-      }
-
-      o.flags (g);
-      o.fill (f);
-    }
-
-    string request::
-    mime_url_decode (const char* b, const char* e, bool trim)
-    {
-      if (trim)
-      {
-        b += strspn (b, " ");
-
-        if (b >= e)
-          return string ();
-
-        while (*--e == ' ');
-        ++e;
-      }
-
-      string value;
-      value.reserve (e - b);
-
-      char bf[3];
-      bf[2] = '\0';
-
-      while (b != e)
-      {
-        char c (*b++);
-
-        switch (c)
-        {
-        case '+':
-          {
-            value.append (" ");
-            break;
-          }
-        case '%':
-          {
-            if (*b == '\0' || b[1] == '\0')
-            {
-              throw invalid_argument (
-                "::web::apache::request::mime_url_decode short");
-            }
-
-            *bf = *b;
-            bf[1] = b[1];
-
-            char* ebf (nullptr);
-            size_t vl (strtoul (bf, &ebf, 16));
-
-            if (*ebf != '\0')
-            {
-              throw invalid_argument (
-                "::web::apache::request::mime_url_decode wrong");
-            }
-
-            value.append (1, static_cast<char> (vl));
-            b += 2;
-            break;
-          }
-        default:
-          {
-            value.append (1, c);
-            break;
-          }
-        }
-      }
-
-      return value;
-    }
   }
 }
diff --git a/web/mime-url-encoding b/web/mime-url-encoding
new file mode 100644
index 0000000..9ae5d6d
--- /dev/null
+++ b/web/mime-url-encoding
@@ -0,0 +1,26 @@
+// file      : web/mime-url-encoding -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef WEB_MIME_URL_ENCODING
+#define WEB_MIME_URL_ENCODING
+
+#include <string>
+#include <iosfwd>
+
+namespace web
+{
+  void
+  mime_url_encode (const char* v, std::ostream& o);
+
+  std::string
+  mime_url_encode (const char* v);
+
+  std::string
+  mime_url_encode (const std::string& v);
+
+  std::string
+  mime_url_decode (const char* b, const char* e, bool trim = false);
+}
+
+#endif // WEB_MIME_URL_ENCODING
diff --git a/web/mime-url-encoding.cxx b/web/mime-url-encoding.cxx
new file mode 100644
index 0000000..1d68bf3
--- /dev/null
+++ b/web/mime-url-encoding.cxx
@@ -0,0 +1,135 @@
+// file      : web/mime-url-encoding.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <web/mime-url-encoding>
+
+#include <ios>       // hex, uppercase, right
+#include <string>
+#include <iomanip>   // setw(), setfill ()
+#include <ostream>
+#include <sstream>
+#include <cstring>   // size_t, strspn()
+#include <stdexcept> // invalid_argument
+
+using namespace std;
+
+namespace web
+{
+  // Encode characters different from unreserved ones specified in
+  // "2.3.  Unreserved Characters" of http://tools.ietf.org/html/rfc3986.
+  //
+  void
+  mime_url_encode (const char* v, ostream& o)
+  {
+    char f (o.fill ());
+    ostream::fmtflags g (o.flags ());
+    o << hex << uppercase << right << setfill ('0');
+
+    char c;
+    while ((c = *v++) != '\0')
+    {
+      if ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') ||
+          (c >= '0' && c <= '9'))
+      {
+        o << c;
+      }
+      else
+      {
+        switch (c)
+        {
+        case ' ': o << '+'; break;
+        case '.':
+        case '_':
+        case '-':
+        case '~': o << c; break;
+        default:
+          {
+            o << "%" << setw (2) << static_cast<unsigned short> (c);
+            break;
+          }
+        }
+      }
+    }
+
+    o.flags (g);
+    o.fill (f);
+  }
+
+  string
+  mime_url_encode (const char* v)
+  {
+    stringstream o;
+    mime_url_encode (v, o);
+    return o.str ();
+  }
+
+  string
+  mime_url_encode (const string& v)
+  {
+    return mime_url_encode (v.c_str ());
+  }
+
+  string
+  mime_url_decode (const char* b, const char* e, bool trim)
+  {
+    if (trim)
+    {
+      b += strspn (b, " ");
+
+      if (b >= e)
+        return string ();
+
+      while (*--e == ' ');
+      ++e;
+    }
+
+    string value;
+    value.reserve (e - b);
+
+    char bf[3];
+    bf[2] = '\0';
+
+    while (b != e)
+    {
+      char c (*b++);
+      switch (c)
+      {
+      case '+':
+        {
+          value.append (" ");
+          break;
+        }
+      case '%':
+        {
+          if (*b == '\0' || b[1] == '\0')
+          {
+            throw invalid_argument ("::web::mime_url_decode short");
+          }
+
+          *bf = *b;
+          bf[1] = b[1];
+
+          char* ebf (nullptr);
+          size_t vl (strtoul (bf, &ebf, 16));
+
+          if (*ebf != '\0')
+          {
+            throw invalid_argument ("::web::mime_url_decode wrong");
+          }
+
+          value.append (1, static_cast<char> (vl));
+          b += 2;
+          break;
+        }
+      default:
+        {
+          value.append (1, c);
+          break;
+        }
+      }
+    }
+
+    return value;
+  }
+}
diff --git a/web/module b/web/module
index e1cccf0..7398d45 100644
--- a/web/module
+++ b/web/module
@@ -13,6 +13,8 @@
 #include <utility>   // move()
 #include <stdexcept> // runtime_error
 
+#include <butl/path>
+
 namespace web
 {
   // HTTP status code.
@@ -68,10 +70,20 @@ namespace web
   };
 
   using name_values = std::vector<name_value>;
+  using path = butl::path;
 
   class request
   {
   public:
+    using path_type = web::path;
+
+    // Corresponds to abs_path portion of HTTP URL as described in
+    // "3.2.2 HTTP URL" of http://tools.ietf.org/html/rfc2616.
+    // Returns '/' if no abs_path is present in URL.
+    //
+    virtual const path_type&
+    path () = 0;
+
     //@@ Why not pass parameters directly? Lazy parsing?
     //@@ Why not have something like operator[] for lookup? Probably
     //   in name_values.
diff --git a/web/xhtml b/web/xhtml
index b8d6ce0..4fc6119 100644
--- a/web/xhtml
+++ b/web/xhtml
@@ -5,6 +5,8 @@
 #ifndef WEB_XHTML
 #define WEB_XHTML
 
+#include <functional> // function
+
 #include <xml/serializer>
 
 namespace web
@@ -36,9 +38,9 @@ namespace web
   //
   namespace xhtml
   {
-    const char* xmlns = "http://www.w3.org/1999/xhtml";
+    const char* const xmlns = "http://www.w3.org/1999/xhtml";
 
-    using serializer_func = void (*) (xml::serializer&);
+    using serializer_func = std::function<void(xml::serializer&)>;
 
     struct attr_value_base
     {
@@ -124,7 +126,10 @@ namespace web
       operator() (xml::serializer& s) const {s.start_element (xmlns, name);}
 
       virtual serializer_func
-      operator~ () const {return [](xml::serializer& s) {s.end_element ();};}
+      operator~ () const
+      {
+        return [this](xml::serializer& s) {s.end_element (xmlns, name);};
+      }
 
       // s << elem(attr1 = 123, attr2 = "abc");
       //
@@ -143,8 +148,11 @@ namespace web
         return attr_element (*this, a1);
       }
 
-    protected:
-      element () = default;
+// @@ Now always need to provide element name, so operator~ () could create
+//    the lambda capable to pass a valid name to end_element call.
+//
+//    protected:
+//    element () = default;
     };
 
     struct inline_element: element
@@ -162,9 +170,9 @@ namespace web
       virtual serializer_func
       operator~ () const
       {
-        return [](xml::serializer& s)
+        return [this](xml::serializer& s)
         {
-          s.end_element (); s.resume_indentation ();
+          s.end_element (xmlns, name); s.resume_indentation ();
         };
       }
     };
@@ -194,7 +202,10 @@ namespace web
       operator() (xml::serializer& s) const {s.start_attribute (name);}
 
       virtual serializer_func
-      operator~ () const {return [](xml::serializer& s) {s.end_attribute ();};}
+      operator~ () const
+      {
+        return [this](xml::serializer& s) {s.end_attribute (name);};
+      }
     };
 
     // Elements.
@@ -206,13 +217,13 @@ namespace web
     //
     struct html_element: element
     {
-      html_element () {} // Uninitialized const static.
+      html_element (): element ("html") {}
 
       virtual void
       operator() (xml::serializer& s) const
       {
         s.doctype_decl ("html");
-        s.start_element (xmlns, "html");
+        s.start_element (xmlns, name);
         s.namespace_decl (xmlns, "");
       }
     };
@@ -220,12 +231,12 @@ namespace web
 
     struct head_element: element
     {
-      head_element () {} // Uninitialized const static.
+      head_element (): element ("head") {}
 
       virtual void
       operator() (xml::serializer& s) const
       {
-        s.start_element (xmlns, "head");
+        s.start_element (xmlns, name);
         s.start_element (xmlns, "meta");
         s.attribute ("charset", "UTF-8");
         s.end_element ();
@@ -233,10 +244,13 @@ namespace web
     };
     static const head_element HEAD;
 
+    static const element BODY  ("body");
+    static const element DIV   ("div");
+    static const element P     ("p");
+    static const element STYLE ("style");
     static const element TITLE ("title");
-    static const element BODY ("body");
-    static const element P ("p");
 
+    static const inline_element A ("a");
     static const inline_element B ("b");
     static const inline_element I ("i");
     static const inline_element U ("u");
@@ -246,9 +260,16 @@ namespace web
 
     // Attributes.
     //
-    static const attribute ID ("id");
     static const attribute CLASS ("class");
-    static const attribute STYLE ("style");
+    static const attribute HREF  ("href");
+    static const attribute ID    ("id");
+    static const attribute TYPE  ("type");
+
+// @@ Attribute variable names clash with element variable names.
+//    Should we prefix/suffix attribute names like _STYLE, STYLE_ or there
+//    are some better ideas ?
+//
+//  static const attribute STYLE ("style");
   }
 }
 
diff --git a/www/htdocs/index.html b/www/htdocs/index.html
deleted file mode 100644
index d8c1185..0000000
--- a/www/htdocs/index.html
+++ /dev/null
@@ -1,31 +0,0 @@
-<!DOCTYPE html>
-<html>
-  <head>
-    <meta name="viewport" content="width=device-width, initial-scale=1"/>
-    <style type="text/css">
-body {
-  font-size        : 1.1em;
-  line-height      : 1.4em;
-
-  text-align: justify;
-
-
-  /* 320px ~ 20em @ 1 font-size. This is factored in when doing font
-     boosting. Specifying 320px directly seems to mess it up. */
-  min-width: 17em;
-  max-width: 40em;
-}
-    </style>
-  </head>
-  <body>
-    <p>Home Page</p>
-    build2 is a build system aimed at improving cross-platform  C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed build2 is a build system aimed at improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed at improving cross-platform C++  at improving cross-platform C++  at improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed at ddw  improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed at improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed at improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build sdhjsd  system aimed at improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-    build2 is a build system aimed at rkdf improving cross-platform C++ software building and library use. It will be accompanied by a C++ package manager and a central repository of open source C++ libraries.
-  </body>
-</html>