Defining project name inside docker-compose configuration - docker-compose

Can you actually define the project name inside the compose configuration file itself, rather than as an environment variable or command-line flag?
I suspect it may avoid some trouble in some scenarios.
I guess overriding that name might still be possible by env or flag.

Not yet (as of version 1.6.2), however, it is being discussed https://github.com/docker/compose/issues/745

Related

how to disclude development.conf from docker image creation of play framework application artifact

Using scala playframework 2.5,
I build the app into a jar using sbt plugin PlayScala,
And then build and pushes a docker image out of it using sbt plugin DockerPlugin
Residing in the source code repository conf/development.conf (same where application.conf is).
The last line in application.conf says include development which means that in case development.conf exists, the entries inside of it will override some of the entries in application.conf in such way that provides all default values necessary for making the application runnable locally right out of the box after the source was cloned from source control with zero extra configuration. This technique allows every new developer to slip right in a working application without wasting time on configuration.
The only missing piece to make that architectural design complete is finding a way to exclude development.conf from the final runtime of the app - otherwise this overrides leak into production runtime and obviously the application fails to run.
That can be achieved in various different ways.
One way could be to some how inject logic into the build task (provided as part of the sbt pluging PlayScala I assume) to exclude the file from the jar artifact.
Other way could be injecting logic into the docker image creation process. this logic could manually delete development.conf from the existing jar prior to executing it (assuming that's possible)
If you ever implemented one of the ideas offered,
or maybe some different architectural approach that gives the same "works out of the box" feature, please be kind enough to share :)
I usually have the inverse logic:
I use the application.conf file (that Play uses by default) with all the things needed to run locally. I then have a production.conf file that starts by including the application.conf, and then overrides the necessary stuff.
for deploying to production (or staging) I specify the production/staging.conf file to be used
This is how I solved it eventually.
conf/application.conf is production ready configuration, it contains placeholders for environment variables whom values will be injected in runtime by k8s given the service's deployment.yaml file.
right next to it, conf/development.conf - its first line is include application.conf and the rest of it are overrides which will make the application run out of the box right after git clone by a simple sbt run
What makes the above work, is the addition of the following to build.sbt :
PlayKeys.devSettings := Seq(
"config.resource" -> "development.conf"
)
Works like a charm :)
This can be done via the mappings config key of sbt-native-packager:
mappings in Universal ~= (_.filterNot(_._1.name == "development.conf"))
See here.

Passing RAILS_ENV into Torquebox without using a Deployment Descriptor

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.

How to add application.conf files for akka multi-jvm applications

I have created a set of applications in akka in the multi-jvm. Following all the conventions on the docs http://doc.akka.io/docs/akka/snapshot/dev/multi-jvm-testing.html I can run them using multi-jvm:run {application name}.
This behaves perfectly but the applications now require remote akka features. To do this I need to change settings in application.conf as mentioned here: http://doc.akka.io/docs/akka/snapshot/scala/remoting.html
My problem is that I do not now how to give each of these multi-jvm test applications an application.conf file of their own. I'm not sure if their is a file-system based convention, or it has to be done in code. Either solution would solve the problem in theory.
I suggest that you define the configuration in code in the test using ConfigFactory.parseString and use that in MultiNodeConfig.commonConfig.
Note that you can use define specific config per node with MultiNodeConfig.nodeConfig.
The application.conf's are loaded from the class path, but you can override them with system properties as described here: https://github.com/typesafehub/config#standard-behavior
So for each JVM, you can specify the necessary System properties(which is kind of ugly), or you can drop an application.conf in the classpath of each JVM that overrides the reference.conf's in the libraries.

Set environment variable at the project level

Using PyDev with Eclipse Juno, I need to set some environment variables to debug every single of the many scripts in my project. I have found how to set them for a given script but it would be totally impractical to do it for all of them. The only solution I have found consists in adding those variable to the Python interpreter configuration in the Preferences. But then it will be used by all projects, which I don't want.
I thought of creating a script setting those environment variables and then launching Python, and then add it as a new Python interpreter but PyDev does not accept two interpreters with the same actual exe (I guess it checks sys.executable).
The recommended approach is really setting it at the Python interpreter level.
You can use virtualenv ( http://pypi.python.org/pypi/virtualenv ) to create a copy of your interpreter in a different path.
Just to elaborate that #FabioZadrozny's answer meets the need of the OP...
In case it hasn't occurred to you, do this:
From the menu "Window->Preference"
Navigate to "PyDev->Interpreters->Python Interpreter"
Create a new interpreter instance with "New..." button
Name it something like "python-MyProj", but use the same executable you are already using
Now in the "Environment" tab for that interpreter, set up the needed environment variable
Now, see the PyDev project to use THAT interpreter:
Right-click the project to get "Properties..."
Navigate to "PyDev-Interpreter/Grammar"
Select the newly created interpreter instance by name
Now run any python file within the project, and it should "see" the configured environment variable.
By this mechanism, you do have a "project specific setting"... which, again, for the reasons #FabioZadrozny pointed out, need to be set at the interpreter level.

How to set up environment variable for all tests in Eclipse?

Setting up environment variables for hundreds of tests get old very quick. Is there a way to declare an environmental variable globally in Eclipse?
Can this be done in Eclipse? Can this be done outside of Eclipse?
It seems that the only way to do it is to enable "Run all tests in the selected project .." and set Environment variables once there.
If you want to run a single test, and that test requires an environment variable set, it looks like you need to set that environment variable as part of that tests's settings.
In windows use the "start" command to spawn eclipse from command line with defined variables (linux has similar functionality)
Make file starteclipse.cmd
================================
SET VAR1=SOMEVALUE
SET VAR2=SOMEVALUE
start d:\eclipse\eclipse.exe
================================
From command line go to the dir with starteclipse.cmd file and run it.
This will spawn eclipse with proper environment settings.
I also find it frustrating having to set env vars one by one.
If you own the code and have a chance to change it, you'd be better off using a System property instead, which can be passed as VMArgs -Dprop=val.
You can set VM args in a global level - Preferences | Java | Installed JREs, and Plugin Development | Target platform.
Even if you can't change the code, most well civilised java libs support properties as well if not more than env vars- so it's worth double checking.
(of course it's not an option for external processes).