@janus-idp/backstage-plugin-orchestrator-form-api v1.4.0

@janus-idp/backstage-plugin-orchestrator-form-api

Overview

This library offers the flexibility to override a selected list of properties of the react-jsonschema-form workflow execution form component. It allows customers to provide a custom decorator for the form component in a backstage plugin. This decorator enables users to:

• Dynamic Validations: Override the extraErrors property to implement dynamic validation logic.
• Custom Components: Replace default components by overriding the widgets property.
• Correlated Field Values: Implement complex inter-field dependencies by overriding the onChange and the formData properties.

The decorator will be provided through a factory method that leverages a Backstage utility API offered by the orchestrator.

Interface Provided in this package

export type FormDecorator = (
  FormComponent: React.ComponentType<Partial<FormProps>>,
) => React.ComponentType;

export interface FormExtensionsApi {
  getFormDecorator(schema: JSONSchema7): FormDecorator;
}

Example API Implementation

class CustomFormExtensionsApi implements FormExtensionsApi {
  getFormDecorator(schema: JSONSchema7) {
    return (FormComponent: React.ComponentType<Partial<FormProps>>) => {
      const widgets = {CountryWidget};
      return () => <FormComponent widgets={widgets} />;
    };
  }
}

Plugin Creation Example

export const formApiFactory = createApiFactory({
  api: orchestratorFormApiRef,
  deps: {},
  factory() {
    return new CustomApi();
  },
});

export const testFactoryPlugin = createPlugin({
  id: 'testfactory',
  apis: [formApiFactory],
});

Schema example for above plugin

{
  "title": "Product",
  "type": "object",
  "properties": {
    "name": {
      "type": "string",
      "title": "Name"
    },
    "country": {
      "type": "string",
      "title": "Country",
      "description": "Country of residence",
      "ui:widget": "CountryWidget"
    }
  },
  "required": ["name", "country"]
}

dynamic plugin configuration

add the following to app-config.local.yaml for integrating a dynamic plugin

dynamicPlugins:
  frontend:
    backstage-plugin-testfactory:
      apiFactories:
        - importName: formApiFactory

Additional Details

The workflow execution schema adheres to the json-schema format, which allows for extending the schema with custom properties beyond the official specification. This flexibility enables the inclusion of additional UiSchema fields directly within the schema, as demonstrated in the example above.

The orchestrator plugin handles the separation of UI schema fields from the main schema. It also organizes the form into wizard steps based on an additional hierarchical structure within the JSON schema.