I've been setting up my rails application to run under jruby/warbler inside a java container (JBoss/wildfly). I'm used to running my rails apps on linux machines, more or less with init.d scripts and the like, and I've been using DATABASE_URL to set the connection without putting my credentials in the source.
Warbler itself is created a pre-packaged WAR, I can deploy that to wildfly(jboss) fine.. but there is no examples of how to set environment variables in the context of that application.
I've googled links, but they are cryptic as hell, there's even a stack overflow question here, but the accepted answer seems to be make your own service between to do this?.
Is there an easy way to pass config to wars in jboss?, or do all java enterprisey applications just store the credentials/urls in the war themselves O.O
You could setup a datasource on the application server
https://docs.jboss.org/author/display/WFLY8/DataSource+configuration
And in your application you will need to use ActiveRecord-JDBC-Adapter
https://github.com/jruby/activerecord-jdbc-adapter
Or you can also set environment variables in the application servers's startup script (bin/standalone.sh or bin/domain.sh)
if you're using Warbler (JRuby-Rack) the environment can be isolated using a context-parameter setting in the deployment descriptor e.g. :
<context-param>
<param-name>jruby.runtime.env</param-name>
<param-value>
DATABASE_URL=mysql://192.168.1.11/mydb
PATH=/usr/local/bin,HOME=/home/tomcat
</param-value>
</context-param>
it's pretty easy to set with Warbler's configuration file (generate one at config/warbler.rb using warble config)
https://github.com/jruby/jruby-rack/wiki/ENV-Isolation#warbler
Related
We know that during Tomcat startup, it will deploy the .war files of its web applications. My question is after the deployment I need to run a command to modify a file inside WEB-INF/ of the web application which is generated after deployment, and I need to let Tomcat do this automatically for me, is this possible to achieve ? Something like post_run command after deployment.
I found that CustomEventHookListener can probably do this How to run script on Tomcat startup?, but this involves in making a new Java class, and I'm not allowed to do so. I have to figure out way to modify the existing Tomcat configs like server.xml or tomcat.conf in TOMCAT_HOME/conf to do so.
The main issue about not using a Event Hook Listener is that there's no reliable way to tell if the application is ready or not, as Catalina implements it's own lifecycle for each of their components (as seen in https://tomcat.apache.org/tomcat-8.5-doc/api/org/apache/catalina/Lifecycle.html).
Your best shot is to use tail or some external program infer the component's state, but AFAIK there's no way to implement listeners directly in the configuration files.
In particular, for test-cases, I want to keep the test database separate so that the test cases don't interfere with development or production databases.
What are some good practices for separating development, test and production environments?
EDIT1: Some context
In Ruby On Rails, there are different configuration files by convention for different environments. So does Play! 2 also support that ?
Or, do I have to cook the configuration files, and then write some glue code that selects the appropriate configuration files ?
At the moment if I run sbt test it uses development database ( configured as "default" in conf/application.conf ). However I would like Play!2 to use a different test database.
EDIT2: On commands that play provides
For Play! 2 framework, I observed this.
$ help play
Welcome to Play 2.2.2!
These commands are available:
-----------------------------
...OUTPUT SKIPPED...
run <port> Run the current application in DEV mode.
test Run Junit tests and/or Specs from the command line
start <port> Start the current application in another JVM in PROD mode.
...OUTPUT SKIPPED...
There are three well defined commands for "test", "development" and "production" instances which are:
test: This runs the test cases. So it should automatically select test configuration.
run <port>: this runs the development instance on the specified port. So this command should automatically select development configuration.
start <port>: this runs the production instance on the specified port. So this should automatically select production configuration.
However, all these commands select the values that are provided in conf/application.conf. I feel there is some gap to be filled here.
Please do correct me if I am wrong.
EDIT3: Best approach is using Global.scala
Described here: How to manage application.conf in several environments with play 2.0?
Good practice is keeping separate instances of the application in separate folders and synching them i.e. via git repo.
When you want to keep single instance you can use alternative configuration file for each environment.
In your application.conf file there is an entry (or entries) for your database, e.g. db.default.url=jdbc:mysql://127.0.0.1:3306/devdb
The conf file can read environment variables using ${?ENV_VAR_NAME} syntax, so change that to something like db.default.url=${?DB_URL} and use environment variables.
A simpler way to get this done and manage your configuration easier is via GlobalSettings. There is a method you can override and that its name is "onLoadConfig". Try check its api at API_LINK
Basically on your conf/ project folder, you'll setup similar to below:
conf/application.conf --> configurations common for all environment
conf/dev/application.conf --> configurations for development environment
conf/test/application.conf --> configurations for testing environment
conf/prod/application.conf --> configurations for production environment
So with this, your application knows which configuration to run for your specific environment mode. For a code snippet of my implementation on onLoadConfig try check my article at my blog post
I hope this is helpful.
I am wondering if there is a way to pass a value for RAILS_ENV directly into the Torquebox server without going through a deployment descriptor; similar to how I can pass properties into Java with the -D option.
I have been wrestling with various deployment issues with Torquebox over the past couple weeks. I think a large part of the problem has to do with packaging the gems into the Knob file, which is the most practical way for managing them on a Window environment. I have tried archive deployment and expanded deployment; with and without external deployment descriptor.
With an external deployment descriptor, I found the packaged Gem dependencies were not properly deployed and I received errors about missing dependencies.
When expanded, I had to fudge around a lot with the dependencies and what got included in the Knob, but eventually I got it to deploy. However, certain files in the expanded Knob were marked as failed (possible duplicate dependencies?), but they did not affect the overall deployment. The problem was when the server restarted, deployment would fail the second time mentioning it could not redeploy one of the previously failed files.
The only one I have found to work consistently for me is archive without external deployment descriptor. However, I still need a way to tell the application in which environment it is running. I have different Torquebox instances for each environment and they only run the one application, so it would be fairly reasonable to configure this at the server level.
Any assistance in this matter would be greatly appreciated. Thank you very much!
The solution I finally came to was to pass in RAILS_ENV as a Java property to the Torquebox server and then to set ENV['RAILS_ENV'] to this value in the Rails boot.rb initializer.
Step 1: Set Java Property
First, you will need to set a Rails Environment java property for your Torquebox server. To keep with standard Java conventions, I called this rails.env.
Dependent on your platform and configuration, this change will need to be made in one of the following scripts:
Using JBoss Windows Service Wrapper: service.bat
Standalone environment: standalone.conf.bat (Windows) or standalone.conf (Unix)
Domain environment:: domain.conf.bat (Windows) or domain.conf (Unix)
Add the following line to the appropriate file above to set this Java property:
set JAVA_OPTS=%JAVA_OPTS% -Drails.env=staging
The -D option is used for setting Java system properties.
Step 2: Set ENV['RAILS_ENV'] based on Java Property
We want to set the RAILS_ENV as early as possible, since it is used by a lot of Rails initialization logic. Our first opportunity to inject application logic into the Rails Initialization Process is boot.rb.
See: http://guides.rubyonrails.org/initialization.html#config-boot-rb
The following line should be added to the top of boot.rb:
# boot.rb (top of the file)
ENV['RAILS_ENV'] = ENV_JAVA['rails.env'] if defined?(ENV_JAVA) && ENV_JAVA['rails.env']
This needs to be the first thing in the file, so Bundler can make intelligent decisions about the environment.
As you can see above, a seldom mentioned feature of JRuby is that it conveniently exposes all Java system properties via the ENV_JAVA global map (mirroring the ENV ruby map), so we can use it to access our Java system property.
We check that ENV_JAVA is defined (i.e. JRuby is being used), since we support multiple deployment environments.
I force the rails.env property to be used when present, as it appears that *RAILS_ENV* already has a default value at this point.
We have a GWT Application that has to link another Application.
This link is different in all stages of my application (local, test, staging, prod). What options are there to configure a GWT app?
Currently we're using properties files for every environment. The problem with this solution is, that we have to create different packages for all the environments. That's bad and we want to build one single package that is deployable to all environments.
But how can we tell the application which configuration to use?
If you are lord of the rings fan -
One Build to rule them all, One Build to find then,
One Build to work on all and in the environment bind them
In the Land of Testing where the Shadows lie.
Solution at our workspace
All the environment specific properties file are pushed into template folder ( log4j_prod.properties,log4j_stage.properties, hibernate.properties etc )
Prod properties file are default and pushed to WEB-INF/classes
QA team modifies the property files using the template files for any other environment.
I too would be curious if it is done any other way :)
If you want to know weather the application is running in which mode , there are some static methods in GWT class .
isClient()
Returns true when running inside the normal GWT environment, either in Development Mode or Production Mode. Returns false if this code is running in a plain JVM. This might happen when running shared code on the server, or during the bootstrap sequence of a GWTTestCase test.
isProdMode()
Returns true when running in production mode. Returns false when running either in development mode, or when running in a plain JVM.
isScript()
Determines whether or not the running program is script or bytecode.
etc....
Based upon tha flags you can configure the folder name of the properties
Documentation says if you have a context file here:
$CATALINA_HOME/conf/Catalina/localhost/myapp.xml
it will NOT be replaced by a context file here:
mywebapp.war/META-INF/context.xml
It is written here: http://tomcat.apache.org/tomcat-6.0-doc/config/context.html
Only if a context file does not exist for the application in the $CATALINA_BASE/conf/[enginename]/[hostname]/, in an individual file at /META-INF/context.xml inside the application files.
But everytime I re-deploy the war it replaces this myapp.xml with the /META-INF/context.xml!
Why does it do it and how can I avoid it?
Thanx
Undeploy part of redeploy deletes app and the associated context.xml.
If you use maven tomcat plugin you can avoid deleting context.xml if you deploy your app with command like this:
mvn tomcat:deploy-only -Dmaven.tomcat.update=true
More info here: https://tomcat.apache.org/maven-plugin-2.0-beta-1/tomcat7-maven-plugin/deploy-only-mojo.html
You can use deploy-only with parameter mode to deploy the context.xml too.
The short answer:
Just make the TOMCATHOME/conf/Catalina/localhost dir read-only, and keep reading for more details:
For quick deployment mode (Eclipse dynamic web project, direct Tomcat
connection, etc.) on a local/non-shared Tomcat server you can just define your JDBC datasource (or any
other 'web resource') using the META-INF/context.xml file inside the
WAR file. Easy and fast in your local environment, but not suitable for staging, QA, or
production.
For build deployment mode (usually for staging, QA, or prod), JDBC
datasources and other 'web resources' details are defined by the
QA/production team, not the development team anymore. Therefore, they
must be specified in the Tomcat server, not inside the WAR file
anymore. In this case, specify them in the file
TOMCATHOME/conf/Catalina/localhost/CONTEXT.xml (change Catalina
by the engine, and localhost by the host, and CONTEXT by your context accordingly). However,
Tomcat will delete this file on each deployment. To prevent this
deletion, just make this dir read-only; in Linux you can type:
chmod a-w TOMCATHOME/conf/Catalina/localhost
Voila! Your welcome.
The long answer
For historical reasons Tomcat allows you to define web resources (JDBC datasources, and others) in four
different places (read four different files) in a very specific order of precedence, if you happen to define the same resource multiple times. The ones named in the
short answer above are the more suitable nowadays for each purpose, though you could still
use the others (nah... you probably don't want to). I'm not going to
discuss the other ones here unless someone asks for it.
On tomcat7, also woth autoDeploy=false the file will be deleted on undeploy. This is documented and not a bug (althought it avoids good automated deployments with server-side fixed configuration).
I found a workaround which solved the problem for me:
create a META-INF/context.xml file in your webapp that contains
on the Server create a second context "/config-context" in server.xml and put all your server-side configuration parameters there
on the application use context.getContext("/config-context").getInitParameter(...) to access the configuration there.
This allows a per-host configuration that is independent of the deployed war.
It should also be possible to add per-context configurations by adding contexts like "/config-context-MYPATH". In your app you can use the context path oth the app to calculate the context path of the config app.
According to the documentation (http://tomcat.apache.org/tomcat-8.0-doc/config/automatic-deployment.html#Deleted_files) upon redeploy tomcat detects the deletion (undeploy) of your application. So it will start a cleanup process deleting the directory and xml also. This is independent of auto deployment - so it will happen upon redeployment through manager and modification of war also. There are 3 exceptions:
global resources are never deleted
external resources are never deleted
if the WAR or DIR has been modified then the XML file is only deleted
if copyXML is true and deployXML is true
I don't know why, but copyXML="false" deployXML="false" won't help.
Secondly: Making the directory read only just makes tomcat throwing an exception and won't start.
You can try merging your $CATALINA_BASE/conf/Catalina/localhost/myapp-1.xml, $CATALINA_BASE/conf/Catalina/localhost/myapp-2.xml, etc files into $CATALINA_BASE/conf/context.xml (that works only if you make sure your application won't deploy its own context configuration, like myapp-1.xml)
If someone could tell what is that "external resources" that would generally solve the problem.
The general issue as described by the title is covered by Re-deploy from war without deleting context which is still an open issue at this time.
There is an acknowledged distinction between re-deploy which does not delete the context, and deploy after un-deploy where the un-deploy deletes the context. The documentation was out of date, and the manager GUI still does not support re-deploy.
Redeployment means two parts: undeployment and deployment.
Undeployment removes the conf/Catalina/yourhost/yourapp.xml because the
<Host name="localhost" appBase="webapps" unpackWARs="true"
autoDeploy="true"> <!-- means autoUndeploy too!!! -->
</Host>
Change the autoDeploy="false" and Tomcat has no order anymore to remove the conf/Catalina/yourhost/yourapp.xml.
There is an feature that allowes us to make those steps (undeploy/deploy) as one single step (redeploy) that do not remove the context.xml. This feature is available via the manager-text-interface, but the option is not available using the manager-html-interface. You might have to wait until the bug in tomcat is fixed. You can use the method described in this answer as an workaround.