deploy-with-sequential-resources

Deploy an MTAR using sequential Resource processing

Table of Contents

• Modelling
  • Service instances having processed-after parameter
• Requirements
• Oficial documemtation in Help SAP Portal
• Try out
  • Deploy the MTA
• Print the MTA details to confirm the deployment

This example shows how to make use of the resource parameter 'processed-after' in order to influence the order of resource processing.

• creation of service instances: https://docs.cloudfoundry.org/devguide/services/managing-services.html

• creation of app bindings to service instances https://docs.cloudfoundry.org/devguide/services/application-binding.html#bind

Modelling

Service instances having processed-after parameter

Whenever order of service processing is necessary, the 'processed-after' parameter comes handy. By using the parameter, we create a sequence of services (an order) in which the services should be processed. For example let’s say service 'A' requires service 'B' and service 'C' to be processed first. On the other hand both service 'B' and service 'C' require service 'D' to be pocessed first. Service 'D' does not require any other service. So the order for processing should be: D → B, C → A. We can achieve this with the following mtad.yaml:

...
resources:
  - name: serviceA
    type: org.cloudfoundry.managed-service
    parameters:
      ...
    processed-after: [serviceB, serviceC]
  - name: serviceB
    type: org.cloudfoundry.managed-service
    parameters:
      ...
    processed-after: [serviceD]
  - name: serviceC
    type: org.cloudfoundry.managed-service
    parameters:
      ...
    processed-after: [serviceD]
  - name: serviceD
    type: org.cloudfoundry.managed-service
    parameters:
      ...

Note	If the parameter 'processed-after' is not specified, the resources are processed in parallel.

Note	The 'processed-after' parameter is supported from schema version 3 onwards. If it’s used in a descriptor with schema version 2 or lower, the following message should appear:

Entities from class "Resource" with schema version "2" do not support this operation. At least "3" is required.

Note	In case two dependencies depend on each other for processing an error will be shown:

Resources "<resource1>" and "<resource2>" both depend on each other for processing

Note	It is NOT allowed a service to depend on itself. If attempt for doing so is made the follwoing error should be displayed:

Resource "{0}" is required by itself for processing

Requirements

• access to a CF space with quota for creation of service instances

Oficial documemtation in Help SAP Portal

• Resources

Try out

Deploy the MTA

The example can be run with 2 approaches for building an MTA. Both lead to the same result.

A. Deeploying from a directory

That approach uses deployment descriptor mtad.yaml and ready application binaries appBits.zip:

cf deploy ./ -f

...
Deploying multi-target app archive /Users/*****/*****/cf-mta-examples/deploy-with-sequential-resources/multiple-anatz.mtar in org deploy-service / space ***** as *********************...

Uploading 1 files...
  /Users/******/******/cf-mta-examples/deploy-with-sequential-resources/multiple-anatz.mtar

OK
Operation ID: ee6a0cf1-3005-11ec-bf71-eeee0a90baae
Operation ID: ee6a0cf1-3005-11ec-bf71-eeee0a90baae
Deploying in org "deploy-service" and space "******"
Detected MTA schema version: "3"
No deployed MTA detected - this is initial deployment
Detected new MTA version: "3.0.0"
Processing service "serviceD"...
Creating service "serviceD" from MTA resource "serviceD"...
1 of 1 done
Processing service "serviceC"...
Creating service "serviceC" from MTA resource "serviceC"...
Processing service "serviceB"...
Creating service "serviceB" from MTA resource "serviceB"...
1 of 1 done
1 of 1 done
Processing service "serviceA"...
Creating service "serviceA" from MTA resource "serviceA"...
1 of 1 done
Creating application "multiple-anatz" from MTA module "multiple-anatz"...
Uploading application "multiple-anatz"...
Started async upload of application "multiple-anatz"
Scaling application "multiple-anatz" to "1" instances...
Staging application "multiple-anatz"...
Application "multiple-anatz" staged
Starting application "multiple-anatz"...
Application "multiple-anatz" started and available at "******   ******-multiple-anatz.cfapps.sap.hana.ondemand.com"
Skipping deletion of services, because the command line option "--delete-services" is not specified.
Process finished.
Use "cf dmol -i ee6a0cf1-3005-11ec-bf71-eeee0a90baae" to download the logs of the process.
...

OR

First assemble an MTA archive using the mtad.yaml` and then deploy the archive:

mbt assemble -t ./ ;
cf deploy multiple-anatz_0.0.0.mtar ;

Note	See mtad.yaml for the modelling

Note	please adjust the service label and plan values to match the available in your environment

B. Build and Deploy

The approach is using development descriptor mta.yaml and application binaries appBits.zip to build MTAR. Then the MTAR is deployed.

mbt build -p cf -t . ;
cf deploy a.cf.app_0.0.0.mtar -f ;

Note	See mta.yaml for the concrete modelling

Print the MTA details to confirm the deployment

At any step you can check the created deployment with the following:

$cf mta multiple-anatz
Showing health and status for multi-target app multiple-anatz in org deploy-service / space ******** as ********...
OK
Version: 3.0.0
Namespace:

Apps:
name             requested state   instances   memory   disk   urls
multiple-anatz   started           1/1         1G       1G     deploy-service-*******-multiple-anatz.cfapps.sap.hana.ondemand.com

Services:
name       service    plan       bound apps   last operation
serviceA   auditlog   standard                create succeeded
serviceB   auditlog   standard                create succeeded
serviceC   auditlog   standard                create succeeded
serviceD   auditlog   standard                create succeeded