Manage extension files

Manage routes as resources, in your Humanitec applications.

  2 minute read  

Score supports extension files.

Overview

Applications that consist of multiple microservices typically need a routing controller that redirects incoming requests to a proper Workload at run time.

For example, a common scenario is to deploy an API Gateway, Ingress controller, or Service mesh as part of your application. Maintaining and updating routing tables after new service deployments is a point of friction as the application scales.

Routing details

With Score, you can include advertised routes details as part of the Workload definition, allowing you to rebuild and update route tables during the deployment process.

Routes convert into resource definitions, so proper routes can be provisioned at the time of deployment based on the target environment and other parameters.

Because of this, define routes as a dependency, or as a resource, that can be referenced in other parts of the Score Specification file.

Routes are just like any other resources. For example, a route would have the name id and a set of attributes like proto, port, prefix, and type. The values of the attributes are available to the Workload at the time of deployment, after the provision of resources takes place.

Routes example

A microservice Workload needs to generate a self-reference in an e-mail that is automatically sends to a user. To build such reference, the service needs to know a full domain, subdomain name, and prefix. Then the service would append a dynamically generated part of the URL that has a unique request IDs to identify the user.

Network configurations may differ depending on the environment setup.

In the following example, DOMAIN_NAME and URL_PREFIX are configured through the environment variables for the microservice and dns and route are two resources that act as dependencies essential for the service’s functionality.

version: score.dev/v1b1
metadata:
  name: resource-example

containers:
  my-service:
     image: ...
     env:
       DOMAIN_NAME: ${resources.dns.domain}
       URL_PREFIX: ${resources.api-route.prefix}

resources:
  dns:
    type: dns
    properties:
      domain:
      ...
  api-route:
    type: route
    properties:
      prefix:
      ...

Humanitec Workload implementation

When translated by score-humanitec, two Workload resources reference would be created in the deployment delta, one for dns and one for route. These would be resolved to actual values based on the configuration specified by the DevOps for the target environment.

Implement ports and volumes