index.tsx

import React from 'react';
import { Entity } from '@backstage/catalog-model';
import { EntityProvider } from '@backstage/plugin-catalog-react';
import { createDevApp } from '@backstage/dev-utils';
import { TestApiProvider } from '@backstage/test-utils';
import { myPluginPlugin, EntityMyPluginContent } from '../src/plugin';
import { MyPluginApi, myPluginApiRef } from '../src';


const mockEntity: Entity = {
  ...
};

class MockMyPluginClient implements MyPluginApi {
  async getHealth(): Promise<{ status: string; }> {
    return { status: 'ok'};
  }
}

createDevApp()
  .registerPlugin(myPluginPlugin)
  .addPage({
    path: '/fixture-1',
    title: 'Fixture 1',
    element: (
      <TestApiProvider
      apis={[[myPluginApiRef, new MockMyPluginClient()]]}
      >
        <EntityProvider entity={mockEntity}>
          <EntityMyPluginContent />
        </EntityProvider>
      </TestApiProvider>
    ),
  })
  .render();