Merge lp:~vasilev/psiphon/sprint3-610176 into lp:psiphon

[Robert Vasilev]

Fixes for https://bugs.launchpad.net/psiphon/+bug/610176

Implemented functionality described in Adam's comment.

1. Added 'back_link' field in 'useragent' table.
2. Patched mod_psiphon_headers.c to retrieve corresponding 'back_link' value from database and store in apache table.
3. Patched bluebar.php to display appropriate compatibility mode exit link.
4. Patched custom_user_agent.php admin page to add 'back_link' manipulating functionality.

Fixes for https://bugs.launchpad.net/psiphon/+bug/610176

1. Patched mod_psifon_headers.c to store custom user agent value in apache table.
2. Patched bluebar.php to display custom user agent value, if such is set up.
3. Added useragent_helpers.php to get simplified browser name from full user agent string.
4. Added stub for future phpunit tests for useragent_helpers.php.

Traslations for lang.php/browse_as value are needed.

[Adam Kruger (adam-kruger)]

The bug description was not clear and so what is implemented is not what was intended.
We would like a link to appear on the bluebar when a custom user agent is being sent (this part was implemented as intended).
The text of the link should be the following: "Exit Compatibility Mode"
The link's href should be a value that is stored in a new column of the user agent table, corresponding to the custom user agent record that is in use.

Please ask if you need any further clarification.

review: Disapprove

[Robert Vasilev (vasilev)]

> The link's href should be a value that is stored in a new column of the user
> agent table, corresponding to the custom user agent record that is in use.

Adam, thank you for comments.

Please clarify what data need to be stored in the new column of user agent table.

We guess that it is "Simplified user agent name", and intended link's href looks like
"/exitCompatibilityMode.php?userAgent=Firefox", where "Firefox" string is stored in the mentioned new field of the DB table.

[Robert Vasilev (vasilev)]

Another question:

How to implement "Exit Compatibility Mode" feature ?
Where are several choices:
1. Per-page.
2. Per-session (psiphon-session).
3. Globally.

If not-per-psiphon-session mode, where do we need to store user per-domain preferences ? In DB ? In cookies ?

[Adam Kruger (adam-kruger)]

Robert, the data stored in the new column of the user agent table will be the link's full href.

We considered the following example to drive the design of this feature:

Some of Facebook's basic features work through Psiphon. Some, like Messages, do not. So when the user clicks on Messages in Facebook, we want to send a mobile user agent along with the request. This actually results in Facebook redirecting to m.facebook.com, and the user is now able to send messages through the m.facebook interface.

The problem at this point is that the user is now at the m.facebook.com site, and we don't want to force the user to hunt for the "Desktop version" or "Full version" link to resume their usual experience with the rest of the site. Our solution here is to provide a link on the bluebar with href="www.facebook.com". This will bring the user back to the usual facebook home screen in desktop mode.

By configuring the full href link in the custom user agent table, we are able to make a decision on a per site basis about how to bring the user back to the desktop version. We accept that this strategy may not be suitable for all websites (ie where the website uses a cookie to decide which content to send).

So the purpose of this feature is 1. to provide the user with some visual feedback indicating that they are browsing in a special compatibility mode, and 2. to provide the user with a link back to the Desktop version of the website, so they don't have to hunt for that link themselves.

To answer your second question, we do not want to store any user per-domain preferences at this time. The "Exit Compatibility Mode" feature should not override any existing Psiphon behavior. It is simply a link that we will configure for each custom user agent entry.

[Robert Vasilev (vasilev)]

Adam, thank you for the answers and descriptive example.

Unmerged revisions

=== modified file 'trunk/mod_psiphon/mod_psiphon_headers/mod_psiphon_headers.c'
--- trunk/mod_psiphon/mod_psiphon_headers/mod_psiphon_headers.c	2010-06-22 17:11:34 +0000
+++ trunk/mod_psiphon/mod_psiphon_headers/mod_psiphon_headers.c	2010-09-01 14:48:14 +0000
@@ -740,6 +740,7 @@
     const char* domain_db = 0;
     const char* path = 0;
     const char* path_db = 0;
+    const char* back_link = 0;
     char* query = 0;
     apr_dbd_results_t* res = 0;
     apr_dbd_row_t* row = 0;
@@ -766,7 +767,7 @@
         return 0;
     }
 
-    query = apr_pstrdup(p, "SELECT domain, path, user_agent_string FROM useragent ORDER BY id DESC");
+    query = apr_pstrdup(p, "SELECT domain, path, user_agent_string, back_link FROM useragent ORDER BY id DESC");
 
     if (error = apr_dbd_select(dbd->driver,p,dbd->handle, &res, query, 0))
     {
@@ -802,9 +803,13 @@
         {
             match_length_so_far = match_length;
             user_agent_string = apr_pstrdup(p, apr_dbd_get_entry(dbd->driver, row, 2));
+            back_link = apr_pstrdup(p, apr_dbd_get_entry(dbd->driver, row, 3));
         }
     }
-
+    if (back_link && *back_link)
+    {
+        apr_table_set(r->subprocess_env, "psiphon_custom_user_agent_back_link", back_link);
+    }
     return user_agent_string;
 }
 
@@ -861,6 +866,7 @@
     {
         /* If we found a non 0 length user agent string, then set the custom user agent */
         apr_table_set(r->headers_in, "User-Agent", user_agent_string);
+        apr_table_set(r->subprocess_env, "psiphon_custom_user_agent", user_agent_string);
     }
 
     /* Add cookies headers from DB for authenticated user*/
 
=== added file 'trunk/sql/upgrade-2.6.sql'
--- trunk/sql/upgrade-2.6.sql	1970-01-01 00:00:00 +0000
+++ trunk/sql/upgrade-2.6.sql	2010-09-01 14:48:14 +0000
@@ -0,0 +1,4 @@
+--
+-- Modifications to table useragent for handling compatibility mode exit link
+--
+ALTER TABLE useragent ADD back_link text;
 
=== modified file 'trunk/tools/psiphon_install.sh'
--- trunk/tools/psiphon_install.sh	2010-06-01 17:50:42 +0000
+++ trunk/tools/psiphon_install.sh	2010-09-01 14:48:14 +0000
@@ -271,7 +271,7 @@
 echo "Enter current password for mysql root (enter for none)"
 
 cat sql/create_db.sql sql/grant.new.sql sql/structure.2.3.sql sql/init.sql \
-sql/upgrade-2.4.sql sql/upgrade-2.5.sql sql/jsf.sql sql/youtube.sql | mysql -uroot -p
+sql/upgrade-2.4.sql sql/upgrade-2.5.sql sql/upgrade-2.6.sql sql/jsf.sql sql/youtube.sql | mysql -uroot -p
 
 rm sql/grant.new.sql
 
 
=== modified file 'trunk/www/bluebar.php'
--- trunk/www/bluebar.php	2010-07-14 20:51:28 +0000
+++ trunk/www/bluebar.php	2010-09-01 14:48:14 +0000
@@ -65,7 +65,6 @@
               !strncmp($uri, "https://", 8))) {
     $uri="";
 }
-
 ?>
 
 <!--bluebar-->
@@ -82,6 +81,12 @@
 <?
 echo $v;
 
+// Indicate custom user agent, if it configured for the proxied URL
+
+if (isset($_SERVER["psiphon_custom_user_agent"]) && isset($_SERVER["psiphon_custom_user_agent_back_link"])) {
+    echo "<a href=\"".$prefix."/".$_SERVER["psiphon_custom_user_agent_back_link"]."\" target=\"_top\">".utf8_encode_string(msg("exit_compatibility_mode"))."</a> |\n";    
+}
+
 // Add link create for Anonymous Users
 
 if (is_anonymous_user($record_user))
 
=== modified file 'trunk/www/custom_user_agent.php'
--- trunk/www/custom_user_agent.php	2010-06-28 20:26:25 +0000
+++ trunk/www/custom_user_agent.php	2010-09-01 14:48:14 +0000
@@ -39,8 +39,8 @@
 if ($_POST['id']=="add")
 {
     $query =
-        "INSERT INTO useragent (domain, path, user_agent_string) ".
-        "VALUES (:domain, :path, :user_agent_string)";
+        "INSERT INTO useragent (domain, path, user_agent_string, back_link) ".
+        "VALUES (:domain, :path, :user_agent_string, :back_link)";
     
     db_query_execute(
         $config,
@@ -48,7 +48,9 @@
         convert_null_array(array(
             ":domain" => $_POST['domain'],
             ":path" => $_POST['path'],
-            ":user_agent_string" => $_POST['user_agent_string'])));
+            ":user_agent_string" => $_POST['user_agent_string'],
+            ":back_link" => $_POST['back_link']
+        )));
     
     $last = db_get_last_insert_id($config);
 }
@@ -62,7 +64,8 @@
         "UPDATE useragent SET ".
             "domain = :domain, ".
             "path = :path, ".
-            "user_agent_string = :user_agent_string ".
+            "user_agent_string = :user_agent_string, ".
+            "back_link = :back_link ".
         "WHERE id = :id";
 
     db_query_execute(
@@ -72,6 +75,7 @@
             ":domain" => $_POST['domain'],
             ":path" => $_POST['path'],
             ":user_agent_string" => $_POST['user_agent_string'],
+            ":back_link" => $_POST['back_link'],
             ":id" => $_POST['id'])));
     
     $last = $_POST['id'];
@@ -123,6 +127,11 @@
                 <?=msg("user_agent_string")?>
                 <br>
                 <textarea name="user_agent_string" cols="60" rows="5"><?=escape_html($_POST['user_agent_string'])?></textarea>
+
+                <br>
+                <?=msg("back_link")?>
+                <br>
+                <textarea name="back_link" cols="60" rows="2"><?=escape_html($_POST['back_link'])?></textarea>
             </td>
 
             <td>
@@ -159,8 +168,8 @@
         echo "<td colspan=\"3\">\n<input type=\"hidden\" name=\"id\" value=\"{$record['id']}\" />\n";
         echo msg("domain")."\n<br>\n<input type=\"text\" name=\"domain\" maxlength=\"64\" size=\"20\" value=\"".$record['domain']."\" />\n<br>\n";
         echo msg("path")."\n<br>\n<input type=\"text\" name=\"path\" maxlength=\"255\" size=\"60\" value=\"".$record['path']."\" />\n<br>\n";
-
-        echo msg("user_agent_string")."\n<br>\n<textarea name=\"user_agent_string\" cols=\"60\" rows=\"5\">\n".$record['user_agent_string']."</textarea>\n</td>\n";
+        echo msg("user_agent_string")."\n<br>\n<textarea name=\"user_agent_string\" cols=\"60\" rows=\"5\">\n".$record['user_agent_string']."</textarea>\n<br>\n";
+        echo msg("back_link")."\n<br>\n<textarea name=\"back_link\" cols=\"60\" rows=\"2\">\n".$record['back_link']."</textarea>\n</td>\n";
 
         echo "<td>{$_p}<input type=\"submit\" value=\"".msg("save")."\" /> &nbsp; <a href=\"".getenv("SCRIPT_NAME")."?fresh={$fresh}\">".msg("cancel")."</a>{$_s}</td>\n";
     }
 
=== modified file 'trunk/www/includes/lang.php'
--- trunk/www/includes/lang.php	2010-08-09 18:56:53 +0000
+++ trunk/www/includes/lang.php	2010-09-01 14:48:14 +0000
@@ -4630,6 +4630,33 @@
 Please begin using this URL to log into Psiphon.",
     ),
 
+    'exit_compatibility_mode' => array(
+        'en' => "Exit Compatibility Mode",
+        'fa' => "Exit Compatibility Mode",
+        'ru' => "Exit Compatibility Mode",
+        'uz' => "Exit Compatibility Mode",
+        'tk' => "Exit Compatibility Mode",
+        'cn' => "Exit Compatibility Mode",
+        'ar' => "Exit Compatibility Mode",
+        'vt' => "Exit Compatibility Mode",
+        'fr' => "Exit Compatibility Mode",
+        'es' => "Exit Compatibility Mode",
+    ),
+
+     'back_link' => array(
+        'en' => "Exit Compatibility Mode link",
+        'fa' => "Exit Compatibility Mode link",
+        'ru' => "Exit Compatibility Mode link",
+        'uz' => "Exit Compatibility Mode link",
+        'tk' => "Exit Compatibility Mode link",
+        'cn' => "Exit Compatibility Mode link",
+        'ar' => "Exit Compatibility Mode link",
+        'vt' => "Exit Compatibility Mode link",
+        'fr' => "Exit Compatibility Mode link",
+        'es' => "Exit Compatibility Mode link",
+    ),
+
+
 // DO NOT MODIFY THIS LINE -- END OF TRANSLATIONS
 );