Dependencies

DevSpace allows you to define dependencies between several software projects that have a devspace.yaml, e.g. across different git repositories or local folders. This makes DevSpace a great tool for building and deploying software that consists of several microservices. Primary use cases of dependencies are:

• You want to reuse an already existing devspace.yaml of another project
• You want to define a more complex pipeline with multiple build, hook and deploy steps
• You want to define a common build / deploy step for other projects

Dependencies for DevSpace projects are defined within the dependencies section of devspace.yaml.

Git Repository

dependencies:
- name: api-server 
  source:
    git: https://github.com/my-api-server
    branch: stable
  dev:
    ports: true
- name: auth-server
  source:
    git: https://github.com/my-auth-server
    revision: c967392
  profile: production
- name: database-server
  source:
    git: https://github.com/my-database-server
    tag: v3.0.1
    subPath: /configuration
  vars:
    - name: ROOT_PASSWORD
      value: ${ROOT_PASSWORD}

Local Path

dependencies:
- name: component-1
  source:
    path: ./component-1
- name: component-2
  source:
    path: ./component-2

Dependency Source

DevSpace is able to work with dependencies from the following sources:

• git repository as dependency that has a devspace configuration
• path to a local folder that contains a dependency (path is relative to the current project's root directory)

Execution Order

Dependencies will be executed in the order that they are specified under dependencies and always before image building and deployments defined in the top-level devspace.yaml. dev configuration that should be reused from a dependency will be executed alongside regular dev configuration specified in the top-level devspace.yaml after the DevSpace deployment pipeline ran through. Example:

dependencies:
- name: dep1
  source:
    path: dep1
  dev:
    sync: true
- name: dep2
  source:
    path: dep2
  dev:
    ports: true
images:
  image1:
    image: myimage/image
deployments:
- name: deployment1
  helm:
    ...
dev:
  ports: ...
  sync: ...

Explanation

In the above devspace.yaml, execution order would be as followed:

• Execute dependency dep1's pull secrets, image building & deployments (if dep1 has other dependencies as well, execute those first)
• Execute dependency dep2's pull secrets, image building & deployments
• Build image image1
• Deploy deployment deployment1
• Start merged portforwarding from dep2 and dev.ports
• Start sync from dep1 and dev.sync

Referencing Dependencies

Reference Image Names

You can reference dependencies images via my-dependency.image in the ./devspace.yaml:

dependencies:
- name: dep1
  source:
    path: dep1
dev:
  # Will open a terminal to the pod with the 
  # image from dep1
  terminal:
    imageSelector: ${runtime.dependencies.dep1.images.image1}

With dep1/devspace.yaml:

images:
  image1:
    image: myusername/devspace
deployments:
  - name: quickstart
    helm:
      componentChart: true
      values:
        containers:
          - image: myusername/devspace

Referencing Dependencies in Deployment Values / Manifests

It is also possible to reference a dependency's image with runtime variables in a deployment:

dependencies:
- name: dep1
  source:
    path: dep1
deployments:
  - name: quickstart
    helm:
      componentChart: true
      values:
        containers:
          - image: ${runtime.dependencies.dep1.image1.image}:${runtime.dependencies.dep1.image1.tag} # -> replaced with 'myusername/devspace:xxxx' 

With a dependency dep1/devspace.yaml that looks like:

images:
  image1:
    image: myusername/devspace

Dependency Resolution

When a DevSpace project has dependencies, DevSpace will:

1. Resolve all dependencies in a recursive manner and give the dependency an ID based on its path or git repository
2. Build a non-cyclic dependency tree where each dependency only occurs once (but could have multiple edges)
3. Choose a leave node from the dependency tree, build its images (unless skip is defined) and deploy its deployments as well as execute defined hooks or pull secrets
4. Remove the leave node from the tree and repeat step 3 until everything has been deployed

The algorithm used by DevSpace for building and deploying dependencies ensures that all dependencies have been deployed in the correct order before the project you are calling DevSpace from will be built and deployed.

Redundant Dependencies

If DevSpace detects that two projects within the dependency tree define the same child-dependency (i.e. a redundant dependency), DevSpace will try to resolve this by removing the dependency that is "higher" (i.e. found first when resolving dependencies) within the tree.

Circular Dependencies

If DevSpace detects two projects which define each other as dependencies (either directly or via child-dependencies), DevSpace will print a warning showing the problematic dependency path within the dependency tree.

Useful Commands

devspace update dependencies

If you want to force DevSpace to update the dependencies (e.g. git fetch & pull), you can run the following command:

devspace update dependencies