Using OpenApi to describe your services

Orbital can use OpenApi specs to understand what APIs exist, and how to call them.

Orbital uses Semantic schemas to describe how data relates between systems. For OpenAPI, this means enriching return types and input parameters with metadata to describe them semantically.

To do this, we embed Taxi metadata within the OpenApi specs.

​Adding Taxi annotations to OpenApi specs

Taxi annotations use a custom x-taxi-type block within OpenApi specs.

Example:

x-taxi-type:  # The name of the type  name: com.acme.MyType  # Optional.  Indicates if the type should be created if not already present.  create: false

The create element is optional, and overrides the default behaviour.

If create is set to false, then schemas which attempt to publish types that aren’t already defined on the schema server are rejected as compilation errors.

This is to prevent accidental typos.

However, the default behaviour for create is different between response models and attribute types:

​Describing response types

Response models returned from API calls can be enriched to include semantic metadata

Assigning Taxi type names to models

You can optionally define a custom type name for response types being published to Orbital. If omitted, then the type name is inferred from the rest of the schema

components:  schemas:    Pet:      # Assign a Taxi type name to the model.      # Optional      x-taxi-type:        name: petstore.Pet      # Everything else is standard OpenApi spec...      allOf:        - $ref: '#/components/schemas/NewPet'        - required:

Adding type annotations to attributes

Enrich attributes with semantic type metadata

NewPet:  required:    - name  properties:    name:      x-taxi-type:        name: petstore.Name      type: string    tag:      x-taxi-type:        name: petstore.Tag      type: string

By default, it’s expected that types referred to in x-taxi-type within attributes have already been defined on the schema server, as part of your core taxonomy.

However, if you are intentionally publishing new types from your OpenApi spec, then set create to true:

NewPet:  required:    - name  properties:    name:      x-taxi-type:        name: petstore.Name        # petstore.Name will be created if not present        create: true      type: string

​Describing service parameters

Inputs into services can also be enriched, to annotate the semantic data required.

Simply add a x-taxi-type annotation to each input, containing a name attribute with a reference to the name of the type from your core taxonomy

## ... OpenApi spec trimmed...paths:  /pets/{id}:    get:      description: Returns a user based on a single ID, if the user does not have access to the pet      operationId: find pet by id      parameters:        - name: id          in: path          description: ID of pet to fetch          required: true          schema:            type: integer            format: int64            x-taxi-type:              name: petstore.PetId  # <-- Name of type from core taxonomy

​Publishing OpenAPI specs to Orbital

Once you have added taxi annotations to your OpenApi spec, you’re ready to publish it to Orbital.

​Different ways to publish OpenAPI specs

There are a few different ways to expose your OpenAPI spec to Orbital, each which suits different team workflows.

​Combining OpenAPI and Taxi in a single project

You can configure your Taxi project to read OpenAPI specs directly by defining their location in the additionalSources section of your taxi.conf file.

Example directory structure:

.├── src/           # Taxi files├── openapi/       # OpenAPI specs└── taxi.conf

Configure in your taxi.conf:

name: com.example/my-taxi-projectversion: 0.2.0sourceRoot: src/additionalSources: {  "@orbital/openapi" : "openapi/*.yaml"}

OpenAPI-specific configuration

You can optionally provide additional metadata for your OpenAPI spec by creating a .taxi.conf file with the same name as your spec.

If no config file is provided, Orbital will use the project’s organization as the default namespace.

Example file structure:

openapi/├── petflix-api-spec.yaml       # Your OpenAPI spec└── petflix-api-spec.taxi.conf  # Optional configuration file

Configuration file contents:

defaultNamespace: "com.petflix.pets"serviceBasePath: "https://petflix.com"

​Guide: Importing OpenAPI projects via the UI

Navigate to /data-source-manager/add within your Orbital UI.

Next, select a project to import into, then choose “Swagger / Open API” from the data source dropdown.

• Either provide the OpenApi spec file directly, or enter a Url to load the spec from.
• Provide a default namespace. (eg: com.petflix.pets). Services from your OpenAPI spec are imported into this namespace
• If your OpenAPI spec doesn’t define a base url (ie.,: servers/url), then specify a Base url. All paths in the OpenApi spec are treated as relative to this path.
• Then click Configure

Preview your imported schema

Your imported OpenApi spec will be available for you to browse, to make sure everything looks correct.

Any types that have been defined as create: true within the Yaml spec should appear wihtin the Types section.

Services and operations should’ve been created for all endpoints within your OpenApi spec.

At this point, you can edit types (by clicking on the pencil icon next to the type name) to further refine your schema. Once you’re happy, click Save, and the OpenApi spec will be imported.