Changes between Initial Version and Version 1 of TracFastCgi


Ignore:
Timestamp:
Feb 28, 2011, 1:07:24 AM (9 years ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • TracFastCgi

    v1 v1  
     1= Trac with FastCGI =
     2
     3[http://www.fastcgi.com/ FastCGI] interface allows Trac to remain resident much like with [wiki:TracModPython mod_python]. It is faster than external CGI interfaces which must start a new process for each request. However, unlike mod_python, FastCGI supports [http://httpd.apache.org/docs/suexec.html Apache SuEXEC], i.e. run with different permissions than web server. Additionally, it is supported by much wider variety of web servers.
     4
     5'''Note for Windows:''' Trac's FastCGI does not run under Windows, as Windows does not implement `Socket.fromfd`, which is used by `_fcgi.py`. If you want to connect to IIS, you may want to try [trac:TracOnWindowsIisAjp AJP].
     6
     7== Simple Apache configuration ==
     8
     9There are two FastCGI modules commonly available for Apache: `mod_fastcgi` and
     10`mod_fcgid` (preferred). The latter is more up-to-date.
     11
     12==== setup with `mod_fastcgi` ====
     13`mod_fastcgi` uses `FastCgiIpcDir` and `FastCgiConfig` directives that should be added to an appropriate Apache configuration file:
     14{{{
     15# Enable fastcgi for .fcgi files
     16# (If you're using a distro package for mod_fcgi, something like
     17# this is probably already present)
     18<IfModule mod_fastcgi.c>
     19   AddHandler fastcgi-script .fcgi
     20   FastCgiIpcDir /var/lib/apache2/fastcgi
     21</IfModule>
     22LoadModule fastcgi_module /usr/lib/apache2/modules/mod_fastcgi.so
     23}}}
     24Setting `FastCgiIpcDir` is optional if the default is suitable. Note that the `LoadModule` line must be after the `IfModule` group.
     25
     26Configure `ScriptAlias` or similar options as described in TracCgi, but
     27calling `trac.fcgi` instead of `trac.cgi`.
     28
     29You can set up the `TRAC_ENV` as an overall default:
     30{{{
     31FastCgiConfig -initial-env TRAC_ENV=/path/to/env/trac
     32}}}
     33
     34Or you can serve multiple Trac projects in a directory like:
     35{{{
     36FastCgiConfig -initial-env TRAC_ENV_PARENT_DIR=/parent/dir/of/projects
     37}}}
     38
     39==== setup with `mod_fcgid` ====
     40Configure `ScriptAlias` (see TracCgi for details), but call `trac.fcgi`
     41instead of `trac.cgi`. Note that slash at the end - it is important.
     42{{{
     43ScriptAlias /trac /path/to/www/trac/cgi-bin/trac.fcgi/
     44}}}
     45
     46To setup Trac environment for `mod_fcgid` it is necessary to use
     47`DefaultInitEnv` directive. It cannot be used in `Directory` or
     48`Location` context, so if you need to support multiple projects, try
     49alternative environment setup below.
     50
     51{{{
     52DefaultInitEnv TRAC_ENV /path/to/env/trac/
     53}}}
     54
     55==== alternative environment setup ====
     56A better method to specify path to Trac environment it to embed the path
     57into `trac.fcgi` script itself. That doesn't require configuration of server
     58environment variables, works for both FastCgi modules
     59(and for [http://www.lighttpd.net/ lighttpd] and CGI as well):
     60{{{
     61import os
     62os.environ['TRAC_ENV'] = "/path/to/projectenv"
     63}}}
     64or
     65{{{
     66import os
     67os.environ['TRAC_ENV_PARENT_DIR'] = "/path/to/project/parent/dir"
     68}}}
     69
     70With this method different projects can be supported by using different
     71`.fcgi` scripts with different `ScriptAliases`.
     72
     73See [https://coderanger.net/~coderanger/httpd/fcgi_example.conf this fcgid example config] which uses a !ScriptAlias directive with trac.fcgi with a trailing / like this:
     74{{{
     75ScriptAlias / /srv/tracsite/cgi-bin/trac.fcgi/
     76}}}
     77
     78== Simple Cherokee Configuration ==
     79
     80The configuration on Cherokee's side is quite simple. You will only need to know that you can spawn Trac as an SCGI process.
     81You can either start it manually, or better yet, automatically by letting Cherokee spawn the server whenever it is down.
     82First set up an information source in cherokee-admin with a local interpreter.
     83
     84{{{
     85Host:
     86localhost:4433
     87
     88Interpreter:
     89/usr/bin/tracd —single-env —daemonize —protocol=scgi —hostname=localhost —port=4433 /path/to/project/
     90}}}
     91
     92If the port was not reachable, the interpreter command would be launched. Note that, in the definition of the information source, you will have to manually launch the spawner if you use a ''Remote host'' as ''Information source'' instead of a ''Local interpreter''.
     93
     94After doing this, we will just have to create a new rule managed by the SCGI handler to access Trac. It can be created in a new virtual server, trac.example.net for instance, and will only need two rules. The '''default''' one will use the SCGI handler associated to the previously created information source.
     95The second rule will be there to serve the few static files needed to correctly display the Trac interface. Create it as ''Directory rule'' for ''/chrome/common'' and just set it to the ''Static files'' handler and with a ''Document root'' that points to the appropriate files: ''/usr/share/trac/htdocs/''
     96
     97Note:\\
     98If the tracd process fails to start up, and cherokee displays a 503 error page, you might be missing the [http://trac.saddi.com/flup python-flup] package.\\
     99Python-flup is a dependency which provides trac with SCGI capability. You can install it on debian based systems with:
     100{{{
     101sudo apt-get install python-flup
     102}}}
     103
     104== Simple Lighttpd Configuration ==
     105
     106The FastCGI front-end was developed primarily for use with alternative webservers, such as [http://www.lighttpd.net/ lighttpd].
     107
     108lighttpd is a secure, fast, compliant and very flexible web-server that has been optimized for high-performance
     109environments.  It has a very low memory footprint compared to other web servers and takes care of CPU load.
     110
     111For using `trac.fcgi`(prior to 0.11) / fcgi_frontend.py (0.11) with lighttpd add the following to your lighttpd.conf:
     112{{{
     113#var.fcgi_binary="/usr/bin/python /path/to/fcgi_frontend.py" # 0.11 if installed with easy_setup, it is inside the egg directory
     114var.fcgi_binary="/path/to/cgi-bin/trac.fcgi" # 0.10 name of prior fcgi executable
     115fastcgi.server = ("/trac" =>
     116   
     117                   ("trac" =>
     118                     ("socket" => "/tmp/trac-fastcgi.sock",
     119                      "bin-path" => fcgi_binary,
     120                      "check-local" => "disable",
     121                      "bin-environment" =>
     122                        ("TRAC_ENV" => "/path/to/projenv")
     123                     )
     124                   )
     125                 )
     126}}}
     127
     128Note that you will need to add a new entry to `fastcgi.server` for each separate Trac instance that you wish to run. Alternatively, you may use the `TRAC_ENV_PARENT_DIR` variable instead of `TRAC_ENV` as described above,
     129and you may set one of the two in `trac.fcgi` instead of in `lighttpd.conf`
     130using `bin-environment` (as in the section above on Apache configuration).
     131
     132Note that lighttpd has a bug related to 'SCRIPT_NAME' and 'PATH_INFO' when the uri of fastcgi.server is '/' instead of '/trac' in this example, see #Trac2418. This should be fixed since lighttpd 1.4.23, and you may need to add `"fix-root-scriptname" => "enable"` as parameter of fastcgi.server.
     133
     134For using two projects with lighttpd add the following to your `lighttpd.conf`:
     135{{{
     136fastcgi.server = ("/first" =>
     137                   ("first" =>
     138                    ("socket" => "/tmp/trac-fastcgi-first.sock",
     139                     "bin-path" => fcgi_binary,
     140                     "check-local" => "disable",
     141                     "bin-environment" =>
     142                       ("TRAC_ENV" => "/path/to/projenv-first")
     143                    )
     144                  ),
     145                  "/second" =>
     146                    ("second" =>
     147                    ("socket" => "/tmp/trac-fastcgi-second.sock",
     148                     "bin-path" => fcgi_binary,
     149                     "check-local" => "disable",
     150                     "bin-environment" =>
     151                       ("TRAC_ENV" => "/path/to/projenv-second")
     152                    )
     153                  )
     154                )
     155}}}
     156Note that field values are different.  If you prefer setting the environment
     157variables in the `.fcgi` scripts, then copy/rename `trac.fcgi`, e.g., to
     158`first.fcgi` and `second.fcgi`, and reference them in the above settings.
     159Note that the above will result in different processes in any event, even
     160if both are running from the same `trac.fcgi` script.
     161{{{
     162#!div class=important
     163'''Note''' It's very important the order on which server.modules are loaded, if mod_auth is not loaded '''BEFORE''' mod_fastcgi, then the server will fail to authenticate the user.
     164}}}
     165For authentication you should enable mod_auth in lighttpd.conf 'server.modules', select auth.backend and auth rules:
     166{{{
     167server.modules              = (
     168...
     169  "mod_auth",
     170...
     171)
     172
     173auth.backend               = "htpasswd"
     174
     175# Separated password files for each project
     176# See "Conditional Configuration" in
     177# http://trac.lighttpd.net/trac/file/branches/lighttpd-merge-1.4.x/doc/configuration.txt
     178
     179$HTTP["url"] =~ "^/first/" {
     180  auth.backend.htpasswd.userfile = "/path/to/projenv-first/htpasswd.htaccess"
     181}
     182$HTTP["url"] =~ "^/second/" {
     183  auth.backend.htpasswd.userfile = "/path/to/projenv-second/htpasswd.htaccess"
     184}
     185
     186# Enable auth on trac URLs, see
     187# http://trac.lighttpd.net/trac/file/branches/lighttpd-merge-1.4.x/doc/authentication.txt
     188
     189auth.require = ("/first/login" =>
     190                ("method"  => "basic",
     191                 "realm"   => "First project",
     192                 "require" => "valid-user"
     193                ),
     194                "/second/login" =>
     195                ("method"  => "basic",
     196                 "realm"   => "Second project",
     197                 "require" => "valid-user"
     198                )
     199               )
     200
     201
     202}}}
     203Note that lighttpd (I use version 1.4.3) stopped if password file doesn't exist.
     204
     205Note that lighttpd doesn't support 'valid-user' in versions prior to 1.3.16.
     206
     207Conditional configuration is also useful for mapping static resources, i.e. serving out images and CSS directly instead of through FastCGI:
     208{{{
     209# Aliasing functionality is needed
     210server.modules += ("mod_alias")
     211
     212# Setup an alias for the static resources
     213alias.url = ("/trac/chrome/common" => "/usr/share/trac/htdocs")
     214
     215# Use negative lookahead, matching all requests that ask for any resource under /trac, EXCEPT in
     216# /trac/chrome/common, and use FastCGI for those
     217$HTTP["url"] =~ "^/trac(?!/chrome/common)" {
     218# Even if you have other fastcgi.server declarations for applications other than Trac, do NOT use += here
     219fastcgi.server = ("/trac" =>
     220                   ("trac" =>
     221                     ("socket" => "/tmp/trac-fastcgi.sock",
     222                      "bin-path" => fcgi_binary,
     223                      "check-local" => "disable",
     224                      "bin-environment" =>
     225                        ("TRAC_ENV" => "/path/to/projenv")
     226                     )
     227                   )
     228                 )
     229}
     230}}}
     231The technique can be easily adapted for use with multiple projects by creating aliases for each of them, and wrapping the fastcgi.server declarations inside conditional configuration blocks.
     232Also there is another way to handle multiple projects and it's to use TRAC_ENV_PARENT_DIR instead of TRAC_ENV and use global auth, let's see an example:
     233{{{
     234#  This is for handling multiple projects
     235  alias.url       = ( "/trac/" => "/path/to/trac/htdocs/" )
     236
     237  fastcgi.server += ("/projects"  =>
     238                      ("trac" =>
     239                        (
     240                          "socket" => "/tmp/trac.sock",
     241                          "bin-path" => fcgi_binary,
     242                          "check-local" => "disable",
     243                          "bin-environment" =>
     244                            ("TRAC_ENV_PARENT_DIR" => "/path/to/parent/dir/of/projects/" )
     245                        )
     246                      )
     247                    )
     248#And here starts the global auth configuration
     249  auth.backend = "htpasswd"
     250  auth.backend.htpasswd.userfile = "/path/to/unique/htpassword/file/trac.htpasswd"
     251  $HTTP["url"] =~ "^/projects/.*/login$" {
     252    auth.require = ("/" =>
     253                     (
     254                       "method"  => "basic",
     255                       "realm"   => "trac",
     256                       "require" => "valid-user"
     257                     )
     258                   )
     259  }
     260}}}
     261
     262Changing date/time format also supported by lighttpd over environment variable LC_TIME
     263{{{
     264fastcgi.server = ("/trac" =>
     265                   ("trac" =>
     266                     ("socket" => "/tmp/trac-fastcgi.sock",
     267                      "bin-path" => fcgi_binary,
     268                      "check-local" => "disable",
     269                      "bin-environment" =>
     270                        ("TRAC_ENV" => "/path/to/projenv",
     271                        "LC_TIME" => "ru_RU")
     272                     )
     273                   )
     274                 )
     275}}}
     276For details about languages specification see [trac:TracFaq TracFaq] question 2.13.
     277
     278Other important information like [http://trac.lighttpd.net/trac/wiki/TracInstall this updated TracInstall page], [wiki:TracCgi#MappingStaticResources and this] are useful for non-fastcgi specific installation aspects.
     279
     280If you use trac-0.9, read [http://lists.edgewall.com/archive/trac/2005-November/005311.html about small bug]
     281
     282Relaunch lighttpd, and browse to `http://yourhost.example.org/trac` to access Trac.
     283
     284Note about running lighttpd with reduced permissions:
     285
     286  If nothing else helps and trac.fcgi doesn't start with lighttpd settings `server.username = "www-data"`, `server.groupname = "www-data"`, then in the `bin-environment` section set `PYTHON_EGG_CACHE` to the home directory of `www-data` or some other directory accessible to this account for writing.
     287
     288
     289== Simple !LiteSpeed Configuration ==
     290
     291The FastCGI front-end was developed primarily for use with alternative webservers, such as [http://www.litespeedtech.com/ LiteSpeed].
     292
     293!LiteSpeed web server is an event-driven asynchronous Apache replacement designed from the ground-up to be secure, scalable, and operate with minimal resources. !LiteSpeed can operate directly from an Apache config file and is targeted for business-critical environments.
     294
     295=== Setup ===
     296
     297 1. Please make sure you have first have a working install of a Trac project. Test install with “tracd” first.
     298
     299 2. Create a Virtual Host for this setup. From now on we will refer to this vhost as !TracVhost. For this tutorial we will be assuming that your trac project will be accessible via:
     300
     301{{{
     302http://yourdomain.com/trac/
     303}}}
     304
     305 3. Go “!TracVhost → External Apps” tab and create a new “External Application”.
     306
     307{{{
     308Name: MyTracFCGI       
     309Address: uds://tmp/lshttpd/mytracfcgi.sock
     310Max Connections: 10
     311Environment: TRAC_ENV=/fullpathto/mytracproject/ <--- path to root folder of trac project
     312Initial Request Timeout (secs): 30
     313Retry Timeout (secs): 0
     314Persistent Connection   Yes
     315Connection Keepalive Timeout: 30
     316Response Bufferring: No
     317Auto Start: Yes
     318Command: /usr/share/trac/cgi-bin/trac.fcgi  <--- path to trac.fcgi
     319Back Log: 50
     320Instances: 10
     321}}}
     322
     323 4. Optional. If you need to use htpasswd based authentication. Go to “!TracVhost → Security” tab and create a new security “Realm”.
     324
     325{{{
     326DB Type: Password File
     327Realm Name: MyTracUserDB               <--- any name you wish and referenced later
     328User DB Location: /fullpathto/htpasswd <--- path to your htpasswd file
     329}}}
     330
     331If you don’t have a htpasswd file or don’t know how to create the entries within one, go to http://sherylcanter.com/encrypt.php, to generate the user:password combos.
     332
     333 5. Go to “!PythonVhost → Contexts” and create a new “FCGI Context”.
     334
     335{{{
     336URI: /trac/                              <--- URI path to bind to python fcgi app we created   
     337Fast CGI App: [VHost Level] MyTractFCGI  <--- select the trac fcgi extapp we just created
     338Realm: TracUserDB                        <--- only if (4) is set. select realm created in (4)
     339}}}
     340
     341 6. Modify `/fullpathto/mytracproject/conf/trac.ini`
     342
     343{{{
     344#find/set base_rul, url, and link variables
     345base_url = http://yourdomain.com/trac/ <--- base url to generate correct links to
     346url = http://yourdomain.com/trac/      <--- link of project
     347link = http://yourdomain.com/trac/     <--- link of graphic logo
     348}}}
     349
     350 7. Restart !LiteSpeed, “lswsctrl restart”, and access your new Trac project at:
     351
     352{{{
     353http://yourdomain.com/trac/
     354}}}
     355
     356== Simple Nginx Configuration ==
     357
     358 1. Nginx configuration snippet - confirmed to work on 0.6.32
     359{{{
     360    server {
     361        listen       10.9.8.7:443;
     362        server_name  trac.example;
     363
     364        ssl                  on;
     365        ssl_certificate      /etc/ssl/trac.example.crt;
     366        ssl_certificate_key  /etc/ssl/trac.example.key;
     367
     368        ssl_session_timeout  5m;
     369
     370        ssl_protocols  SSLv2 SSLv3 TLSv1;
     371        ssl_ciphers  ALL:!ADH:!EXPORT56:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP;
     372        ssl_prefer_server_ciphers   on;
     373
     374        # (Or ``^/some/prefix/(.*)``.
     375        if ($uri ~ ^/(.*)) {
     376             set $path_info /$1;
     377        }
     378
     379        # You can copy this whole location to ``location [/some/prefix]/login``
     380        # and remove the auth entries below if you want Trac to enforce
     381        # authorization where appropriate instead of needing to authenticate
     382        # for accessing the whole site.
     383        # (Or ``location /some/prefix``.)
     384        location / {
     385            auth_basic            "trac realm";
     386            auth_basic_user_file /home/trac/htpasswd;
     387
     388            # socket address
     389            fastcgi_pass   unix:/home/trac/run/instance.sock;
     390
     391            # python - wsgi specific
     392            fastcgi_param HTTPS on;
     393
     394            ## WSGI REQUIRED VARIABLES
     395            # WSGI application name - trac instance prefix.
     396            # (Or ``fastcgi_param  SCRIPT_NAME  /some/prefix``.)
     397            fastcgi_param  SCRIPT_NAME        "";
     398            fastcgi_param  PATH_INFO          $path_info;
     399
     400            ## WSGI NEEDED VARIABLES - trac warns about them
     401            fastcgi_param  REQUEST_METHOD     $request_method;
     402            fastcgi_param  SERVER_NAME        $server_name;
     403            fastcgi_param  SERVER_PORT        $server_port;
     404            fastcgi_param  SERVER_PROTOCOL    $server_protocol;
     405            fastcgi_param  QUERY_STRING     $query_string;
     406
     407            # for authentication to work
     408            fastcgi_param  AUTH_USER          $remote_user;
     409            fastcgi_param  REMOTE_USER        $remote_user;
     410        }
     411    }
     412}}}
     413
     414 2. Modified trac.fcgi:
     415
     416{{{
     417#!/usr/bin/env python
     418import os
     419sockaddr = '/home/trac/run/instance.sock'
     420os.environ['TRAC_ENV'] = '/home/trac/instance'
     421
     422try:
     423     from trac.web.main import dispatch_request
     424     import trac.web._fcgi
     425
     426     fcgiserv = trac.web._fcgi.WSGIServer(dispatch_request,
     427          bindAddress = sockaddr, umask = 7)
     428     fcgiserv.run()
     429
     430except SystemExit:
     431    raise
     432except Exception, e:
     433    print 'Content-Type: text/plain\r\n\r\n',
     434    print 'Oops...'
     435    print
     436    print 'Trac detected an internal error:'
     437    print
     438    print e
     439    print
     440    import traceback
     441    import StringIO
     442    tb = StringIO.StringIO()
     443    traceback.print_exc(file=tb)
     444    print tb.getvalue()
     445
     446}}}
     447
     448 3. reload nginx and launch trac.fcgi like that:
     449
     450{{{
     451trac@trac.example ~ $ ./trac-standalone-fcgi.py
     452}}}
     453
     454The above assumes that:
     455 * There is a user named 'trac' for running trac instances and keeping trac environments in its home directory.
     456 * `/home/trac/instance` contains a trac environment
     457 * `/home/trac/htpasswd` contains authentication information
     458 * `/home/trac/run` is owned by the same group the nginx runs under
     459  * and if your system is Linux the `/home/trac/run` has setgid bit set (`chmod g+s run`)
     460  * and patch from ticket #T7239 is applied, or you'll have to fix the socket file permissions every time
     461
     462Unfortunately nginx does not support variable expansion in fastcgi_pass directive.
     463Thus it is not possible to serve multiple trac instances from one server block.
     464
     465If you worry enough about security, run trac instances under separate users.
     466
     467Another way to run trac as a FCGI external application is offered in ticket #T6224
     468
     469----
     470See also:  TracGuide, TracInstall, [wiki:TracModWSGI ModWSGI], [wiki:TracCgi CGI], [wiki:TracModPython ModPython], [trac:TracNginxRecipe TracNginxRecipe]