Jifty::Manual::Deploying(3pm) User Contributed Perl Documentation Jifty::Manual::Deploying(3pm)
NAME
Jifty::Manual::Deploying - Deploying your application for production use
DESCRIPTION
This document is intended to answer two questions:
o Now that you've developed your Jifty application, how do you deploy it on the production server?
o Once deployed, what's the process for performing upgrades to the production server?
Developers and administrators may wish to use this document as a checklist to make sure they hit everything when deploying. This document
should be updated according to the best practices of Jifty deployment to aid this end.
HOW TO
Installing on a Production Server
Once you've finished developing your Jifty application and you want to deploy it for use on a production server you'll need to follow these
steps:
1. Install Jifty on your production server.
2. Copy your application onto the production server.
3. Adjust the configuration to suit your production environment.
4. Deploy your production database.
5. Configure your web server.
6. Start using your production service.
Install Jifty
Jifty installation proceeds just as it did on your development machine (or machines). If you installed from CPAN, you may do the same for
your production server.
perl -MCPAN -e 'install Jifty'
or download Jifty and run:
tar zxf Jifty-VERSION.tar.gz
cd Jifty-VERSION
perl Makefile.PL
make
make test
sudo make install
You may also have installed it via the package manager available for your Linux distribution.
Finally, you may want to use bleeding-edge features available only in the Jifty Subversion repository. This has a slightly higher risk, but
this is what the Best Practical team does for their Jifty applications. When doing this, you will probably want to be sure to check out the
exact same version as you are using on your development machines.
Be sure to run the tests when installing Jifty to make sure there aren't any problems on your production server that you need to fix before
deploying your application.
Copy the Application
After you've gotten Jifty deployed, you need to copy your application onto the server. This can be done in whatever way suits your project.
You can run your Jifty application straight out of the development directory just as you have on testing. Just place the directory into an
appropriate location on your server.
It may be advisable to consider using a version control system, such as SVK or Subversion, to aid you in this process. For example, with
either SVK or Subversion, any production customizations can be handled as branches of your application to help you keep those changes
sorted out clearly. This can also help you if you make any tweaks to the code on the production server that need to be put back into your
development.
Here is an example of how to create the branch in Subversion or. This example is built upon in the "Upgrading the Production Server"
section below.
All these commands are assumed to be running on the production server in this example, but you could do much of these from anywhere.
svn mkdir http://svn.example.com/myapp/branches
svn copy http://svn.example.com/myapp/trunk
http://svn.example.com/myapp/branches/production
svn checkout http://svn.example.com/myapp/branches/production
myapp
cd myapp
Make sure to remember (possibly by recording it in the log messages) which revision your trunk was at when you ran the copy command. This
will be important later. If you're using SVK rather than Subversion, you don't have to worry about this.
In SVK:
svk mkdir //myapp/branches
svk copy //myapp/trunk //myapp/branches/production
svk checkout //myapp/branches/production myapp
cd myapp
You will now have a copy of the latest version of your project in the directory named myapp. You can then make any of the modifications you
need to to get your application configured for the production environment (read the following sections for details).
When you're finished, commit those changes to the branch:
svn commit
or in SVK:
svk commit
All of these changes will be made only to the production branch. In the upgrade section, it will be clearer how this will help you.
Tweak the Configuration
After you've copied your application onto the server, change into that directory and make any changes to your configuration required for
production.
Put all your site-specific changes in etc/site_config.yml and never edit etc/config.yml, as it will be overwritten with the next
application update.
Here are some things you'll want to consider changing:
AdminMode
While developing, you'll probably want to try running your application with this turned off. This turns on the administrative functions
for managing models, data, and actions.
Set this to 0 to turn it off.
Database
These settings will be covered in more detail in "Deploy the Database".
DevelMode
This turns off certain checks that slow down a production system but are vital to fast development. For example, with ever request to a
server with "DevelMode" turned on, the server checks to see if any of the library or template files have changed and reloads them, if
this is turned on.
By switching this setting off, you also enable extra caching and speed-up features including the use of CSS::Squish, which helps your
application load CSS files more quickly.
LogConfig
You may wish to add this option to specify a custom logger configuration. See Jifty::Logger.
LogLevel
Depending on your environment, you may want to adjust the default log level or you may want to customize the log configuration by
introducing an etc/log4perl.conf configuration file.
You can set the LogLevel to: DEBUG, INFO, WARN, ERROR, or FATAL to specify the level. If you want a custom log configuration for your
server (allowing you to have per-module log settings among other features), you need to set "LogConfig" and possibly "LogReload". See
Jifty::Logger
This configuration setting is overridden by the JIFTY_LOG_LEVEL environment variable (if set).
LogReload
This allows you specify a custom reload period for your log configuration, if you use "LogConfig". See Jifty::Logger.
Mailer
In some cases you will want to adjust the mailer configuration used by Jifty. The mail configuration is used whenever
Jifty::Notification messages are sent, which may or may not be used by your application.
If you change the "Mailer" setting, be sure to also change "MailerArgs" to match.
See Jifty::Notification and Email::Send.
MailerArgs
You may want to adjust the configuration of the mailer you are using. See Jifty::Notification and Email::Send.
Plugins
You may want to disable plugins you've been using in your development that you don't need in production. In general, if these plugins
are well-behaved this isn't necessary, but you can provide yourself with extra insurance in case they are not.
You can disable them without removing them from the file by commenting them out using the Perl-style "#" comment mark.
Web
BaseURL
You will want to change the "BaseURL" setting under "Web" to make sure it shows the name of your production server's base URL.
ServeStaticFiles
If you want to improve the performance of your server, you may want your main web server to serve static files rather than having
Jifty do it. You will need to manually flatten the static file structure yourself for this to work, but it can be done.
etc.
Your application configuration may have additional changes that need to be made for your application to operate properly in a
production environment.
Make sure to check over all the settings to make sure they will work in your production environment to save yourself headaches later.
Deploy the Database
If you've been developing your server using the default SQLite configuration, you will likely want to change this for your production
server. SQLite might work for production environment, but chances are it will not.
For your production system, you will probably want to modify the "Driver" to suit your production environment. For example, if you were
going to change to use a MySQL server, you might change your "Database" configuration in etc/site_config.yml to something like this:
Database:
Database: myapp
Driver: mysql
Host: mysql.example.com
Password: 'secret'
RecordBaseClass: Jifty::DBI::Record::Cachable
User: myapp_user
Version: 0.0.1
In this example, the server is running the MySQL driver, connecting to the host at "mysql.example.com" with the username "myapp_user" and
password "secret".
You will need to create the database and grant access to the users according to your RDBMS administrator documentation. In MySQL, this
could be done to match the example above by running these commands:
mysqladmin -uadmin -psecret create myapp
mysql -uadmin -psecret -e "grant all on myapp.* to myapp_user'@'myapp.example.com identified by 'secret'"
Please refer to your RDBMS documentation for full details on how to configure your database.
Configure the Web Server
There are several ways to configure your web server. You can use FastCGI or mod_perl or you can use a proxy to the Jifty simple server. The
first two options are what you will most likely want to do, but the proxy configuration is presented for completeness.
Configuring FastCGI
Several configurations are explained by the "fastcgi" in Jifty::Script::FastCGI script that comes with Jifty. It is recommended that you
take one of those and modify the configuration to suit your needs.
It may take a few tries to get the configuration exactly right. Be sure to check the server logs for your web server when looking for
problems.
Configuring mod_perl
Support for mod_perl version 2.0 is provided by Jifty::Script::ModPerl2. Remember that you need to completely stop and start the Apache
server after the Perl modules in your application are changed.
Configuring a Proxy
You can use a proxy with the built-in server. This can be done with the following configuration in Apache:
<Location />
ProxyPass / http://localhost:8888/
ProxyPassReverse / http://localhost:8888/
</Location>
Place that declaration in your main configuration or virtual host configuration file and then whenever you run:
bin/jifty server
Apache will proxy your server on port 80 for you. This may not work exactly as expected because the built-in server is intended for
testing, not for a production environment. As such, it is not well-tested as a production server.
Configure File Permissions
The <var/> subdirectory in your application should be writable by the server process. If it runs as non-root UID (for example, FastCGI and
Apache processes are usually running under the user named apache or www or something alike), you need to change the group or user
permissions for this directory.
For example, assume your application will run under user apache and group apache. Then the following commands should do the job:
chgrp -R apache var
chmod -R g+w var
A more flexible way would be to create a new group myapp and add apache user in it. This allows you to maintain the application from non-
root login and use "sudo" for restarting Apache.
All Systems Go
Once you have done all of the above, your application should be ready to use at the production address you have configured.
Updating the Production Server
After you've made some collection of updates to your Jifty application, you'll then need to install those changes onto your server and
prepare your application to use the changes.
This documentation assumes a "cold" upgrade with the application offline during the duration of the process. A future version of this
document might also include instructions for performing a "hot" upgrade without taking the server offline.
You can do this with the following steps:
1. Shutdown the application.
2. Update the Jifty installation.
3. Update your Jifty application.
4. Merge in configuration changes.
5. Clean up any temporary and cached files.
6. Upgrade your database.
7. Start using the updated application.
Shutdown the Application
This process cannot be performed on a live server. If it is, bad things may happen. You may choose to shutdown the application in one of
two ways: turn off your web server or reconfigure your web server into an offline mode.
Remember, shutdown all Jifty application processes before continuing, or bad things may happen!
Shutting Down the Server
This will involve a two step process. First, you will want to shutdown your web server. The second is to shutdown the Jifty server. If you
are using the built-in Jifty server, you may do this by running:
bin/jifty server --stop
If you are using FastCGI, you will need to locate your server's process IDs and then kill all the processes. If this is the only FastCGI
and Perl script running on your system, you may be able to just run:
killall perl
However, that might stop too many processes in many environments, so you'll just have to find the processes and clean them up as suits your
server.
Offline Mode
If you want to provide you site visitors with some feedback letting them know that the web site is down, you might want to provide an
alternative configuration for your application. You still need to stop all your Jifty application processes when you engage the offline
configuration.
For example, you could have the following configuration on an Apache server to run an offline mode:
<Location />
RewriteEngine on
RewriteRule ^.*$ /offline.html
</Location>
Then create a file named "offline.html" in your server root containing the message you wish to give your visitors.
You can make this configuration change and then restart your web server to give it effect. Then, stop all the Jifty application processes.
Update Jifty
This is exactly the same as "Install Jifty" above. Again, you'll probably want to install the same version as you are using to developing
with. If you have not made any changes to the Jifty version you are using, you may skip this step.
Update the Application
This is again similar to what you've done above. You just need to update all the files that have changed. However, you should be careful
not to clobber any configuration changes that you need to remember.
If you've used the suggestion of using a branch described above, you can automatically update your production server to use the latest code
without risk of clobbering your changes on the production server.
In Subversion, you will first need to recall the revision of either the initial copy or of the last merge you performed. If you stored this
information in the log message, you can retrieve it by running:
svn log http://svn.example.com/myapp/branches/production
When you have the revision number, you can then merge in all the latest changes in your production server copy. Here, I assume that the
revision number is "1234".
cd myapp
svn merge -r 1234:HEAD http://svn.example.com/myapp/trunk .
If you're using SVK, you can just run the following:
cd myapp
svk smerge //myapp/trunk .
SVK automatically remembers the revision number for you so you don't have to worry about it.
Next, watch for any conflicts that might have occurred and be sure to correct them. Check over all the changed files and make sure they
look alright and you should also run your tests again to be sure everything is working. Once you're sure everything is correct, you can
accept the changes with:
svn commit
or:
svk commit
Your code should now be ready.
Configuration Changes
Again, you need to look for any configuration updates that need to adjusted. This is no different from the process during the initial
installation.
Clear Temporary/Cached Files
This step is important to prevent strange issues from occurring. You remove all files from the following directories:
o var/mason/cache
o var/mason/obj
You can run the following command (BE CAREFUL TO TYPE THIS CORRECTLY OR PAY THE CONSEQUENCES):
rm -rf var/mason/{cache,obj}/*
This means that your application will have to rebuild these cached files, which will slow your application down slightly at first.
However, if these files are left in place, the Mason server may continue using cached versions of files that don't match your latest
updates. This will lead to very strange problems.
Upgrade the Database
If you've made any changes to the database schema or to the structure of your data that requires an upgrade, you will need to run:
bin/jifty schema --setup
See Jifty::Manual::Upgrading.
All Systems Go
Now that all these changes have been made, you are ready to start your web server or reconfigure your web server for production mode and
restart.
SEE ALSO
Jifty::Manual::Tutorial, Jifty::Manual::Upgrading
perl v5.14.2 2011-02-09 Jifty::Manual::Deploying(3pm)