Development

Learn how to develop an own package.

Getting started

First thing you need to do is to create a repository at e.g., https://github.com/my-organisation/my-velocitas-package. The URL needs to be referenced in the .velocitas.json of your Vehicle App repository.

General configuration of Packages

Every Package repository needs a manifest.json at their root. The manifest.json is the package configuration and holds package relevant information and its behaviour.

Here are examples of this configuration:

The manifest of a package describes a list of components. They are a collection of programs or files that serve a similar purpose or are inheritly connected. I.e. they provide a single runtime, a deployment for a runtime or add configuration required for Github Workflows or the devcontainer.

More detailed information and explanation about configuration fields of the manifest.json and package development can be found here .

Configuration of Runtime Packages

If you want to add a new service, adapt runtime.json and manifest.json . In order to use a newly created or updated service, new changes on devenv-runtimes need to be tagged and referenced inside .velocitas.json of the respective package version via a tag or branch name of the repository. When a version is changed in your .velocitas.json you have to initialize it through velocitas init from the terminal so the new package version will be installed. A new service can be started by using velocitas cli command velocitas exec runtime-local <service_id> <args> which can be also configured inside your ./.vscode/tasks.json.

If you plan to develop a Package with the purpose of managing the runtime used together with your Vehicle App the package needs a runtime.json at their root. The runtime.json is the runtime configuration containing all information for the relevant service dependencies with the following three required attributes:

Property Description
id unique service id
interfaces used for dependency resolution between Vehicle App and runtime
config configurations in form of Key/Value pair with specific pre–defined keys and corresponding values

Supported config keys of a service

Key Value Description
image URI of a container image
port port number
port-forward port mapping for forwarding
env environment variable used by the service: <env_key>=<env_value>
mount path for mounting files: <source_path>:<target_path>
arg argument for starting the service
start-pattern optional start pattern for identifying if the service starts correctly

Runtime configuration helper

{
    "id": "<service_id>",
    "interfaces": [
        "<interface>"
    ],
    "config": [
        {
            "key": "image",
            "value": "<image>:<tag>"
        },
        {
            "key": "port",
            "value": "<port_number>"
        },
        {
            "key": "port-forward",
            "value": "<source_port>:<target_port>"
        },
        {
            "key": "env",
            "value": "<env_key>=<env_value>"
        },
        {
            "key": "mount",
            "value": "<source_path>:<target_path>"
        },
        {
            "key": "arg",
            "value": "<arg>"
        },
        {
            "key": "start-pattern",
            "value": ".*Listening on \\d+\\.\\d+\\.\\d+\\.\\d+:\\d+"
        }
    ]
}

In order to use a newly created or updated service, changes on the respective Package need to be tagged and referenced inside the .velocitas.json of your Vehicle App repository via a tag or branch name of the repository. More info about installation: Usage .

Next steps