Services and env in manifest file? - manifest

Question

I have a web (online calculator for an example) which developed by my fellow tem members. Now they want to deploy in PCF using manifests.
Languages used : python, php and javascipt.
I gone through the docs about pcf with manifest.yml
In that I don't have any idea about services and env.
What is that services and how can I find the services for the above project and also how can I find the environment variables?
And tell whether these fields are mandatory to run the project in PCF.

Answer 1

To your original question:
What is that services and how can I find the services for the above project and also how can I find the environment variables? And tell whether these fields are mandatory to run the project in pcf.
Does your app require any services to run? Services would be things like a database or message queue. If it does not, then you do not need to specify any services in your manifest. They are optional.
Similarly, for environment variables, you would only need to set them if they are required to configure your application. Otherwise, just omit that section of your manifest.
At the end of the day, you should talk with whomever developed the application or read the documentation they produce as that's the only way to know what services or environment variables are required.
In regards to your additional questions:
1)And also I have one more query...like in our application we used python ok! In that we use lots of pacakages say pandas,numpy,scipy and so on...how can I import all the libraries into the PCF ??? Buildpacks will contain version only right?
Correct. The buildpack only includes Python itself. Your dependencies either need to be installed or vendored. To do this for Python, you need to include a requirements.txt file. The buildpack will see this and use pip to install your dependencies.
See the docs for the Python buildpack which explains this in more detail: https://docs.cloudfoundry.org/buildpacks/python/index.html#pushing_apps
2)And also tell me what will be the path for my app name if Java I can enclose jar files
For Java apps, you need to push compiled code. That means, you need to run something like mvn package or gradle assemble to build your executable JAR or WAR file. This should be a self contained file that has everything necessary to run your app, compile class files, config, and all dependent JARs.
You then run cf push -p path/to/my-app.jar (or WAR, whatever you build). The cf cli will take everything in the app and push it up to Cloud Foundry where the Java buildpack will install things like the JVM and possibly Tomcat so you app can run.
what should I do for application devloped using pyhton , JavaScript and php....
You can use multiple buildpacks. See the instructions here.
https://docs.cloudfoundry.org/buildpacks/use-multiple-buildpacks.html
In short, you can have as many buildpacks as you want. The last buildpack in the list is special because that is the buildpack which will set the start command for your application (although you can override this with cf push -c if necessary). The non-final buildpacks will run and simply install dependencies.
3) we were using postgresql how can I use this in pcf with my app
Run cf marketplace and see if there are any Postgres providers in your Marketplace. If there is one, you can just do a cf create-service <provider> <plan> <service name> and the foundation will create a database for you to use. You would then run a cf bind-service <app> <service name> to bind the service you create to your app. This will generate credentials and pass them along to your app when it starts. You app can then read the credentials out of VCAP_SERVICES and use them to make connections to the database.
See here for more details:
https://docs.cloudfoundry.org/devguide/services/application-binding.html
https://docs.cloudfoundry.org/devguide/deploy-apps/environment-variable.html#VCAP-SERVICES