org.springframework.boot.cloud

Class CloudFoundryVcapEnvironmentPostProcessor

  • java.lang.Object
    • org.springframework.boot.cloud.CloudFoundryVcapEnvironmentPostProcessor
  • All Implemented Interfaces:
    EnvironmentPostProcessor, Ordered


    public class CloudFoundryVcapEnvironmentPostProcessor
    extends Object
    implements EnvironmentPostProcessor, Ordered
    An EnvironmentPostProcessor that knows where to find VCAP (a.k.a. Cloud Foundry) meta data in the existing environment. It parses out the VCAP_APPLICATION and VCAP_SERVICES meta data and dumps it in a form that is easily consumed by Environment users. If the app is running in Cloud Foundry then both meta data items are JSON objects encoded in OS environment variables. VCAP_APPLICATION is a shallow hash with basic information about the application (name, instance id, instance index, etc.), and VCAP_SERVICES is a hash of lists where the keys are service labels and the values are lists of hashes of service instance meta data. Examples are:
     VCAP_APPLICATION: {"instance_id":"2ce0ac627a6c8e47e936d829a3a47b5b","instance_index":0,
       "version":"0138c4a6-2a73-416b-aca0-572c09f7ca53","name":"foo",
       "uris":["foo.cfapps.io"], ...}
     VCAP_SERVICES: {"rds-mysql-1.0":[{"name":"mysql","label":"rds-mysql-1.0","plan":"10mb",
       "credentials":{"name":"d04fb13d27d964c62b267bbba1cffb9da","hostname":"mysql-service-public.clqg2e2w3ecf.us-east-1.rds.amazonaws.com",
       "host":"mysql-service-public.clqg2e2w3ecf.us-east-1.rds.amazonaws.com","port":3306,"user":"urpRuqTf8Cpe6",
       "username":"urpRuqTf8Cpe6","password":"pxLsGVpsC9A5S"}
     }]}
     
    These objects are flattened into properties. The VCAP_APPLICATION object goes straight to vcap.application.* in a fairly obvious way, and the VCAP_SERVICES object is unwrapped so that it is a hash of objects with key equal to the service instance name (e.g. "mysql" in the example above), and value equal to that instances properties, and then flattened in the same way. E.g.
     vcap.application.instance_id: 2ce0ac627a6c8e47e936d829a3a47b5b
     vcap.application.version: 0138c4a6-2a73-416b-aca0-572c09f7ca53
     vcap.application.name: foo
     vcap.application.uris[0]: foo.cfapps.io
    
     vcap.services.mysql.name: mysql
     vcap.services.mysql.label: rds-mysql-1.0
     vcap.services.mysql.credentials.name: d04fb13d27d964c62b267bbba1cffb9da
     vcap.services.mysql.credentials.port: 3306
     vcap.services.mysql.credentials.host: mysql-service-public.clqg2e2w3ecf.us-east-1.rds.amazonaws.com
     vcap.services.mysql.credentials.username: urpRuqTf8Cpe6
     vcap.services.mysql.credentials.password: pxLsGVpsC9A5S
     ...
     
    N.B. this initializer is mainly intended for informational use (the application and instance ids are particularly useful). For service binding you might find that Spring Cloud is more convenient and more robust against potential changes in Cloud Foundry.
    Author:
    Dave Syer, Andy Wilkinson
    • Constructor Detail

      • CloudFoundryVcapEnvironmentPostProcessor

        public CloudFoundryVcapEnvironmentPostProcessor()