feat(api): add get flow endpoint

packages/backend/src/controllers/api/v1/flows/get-flow.ee.js

@@ -0,0 +1,12 @@
+import Flow from '../../../../models/flow.js';
+import { renderObject } from '../../../../helpers/renderer.js';
+
+export default async (request, response) => {
+  const flow = await Flow.query()
+    .withGraphJoined({ steps: true })
+    .orderBy('steps.position', 'asc')
+    .findOne({ 'flows.id': request.params.flowId })
+    .throwIfNotFound();
+
+  renderObject(response, flow);
+};

packages/backend/src/controllers/api/v1/flows/get-flow.ee.test.js

@@ -0,0 +1,50 @@
+import Crypto from 'node:crypto';
+import request from 'supertest';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import { createApiToken } from '../../../../../test/factories/api-token.js';
+import { createFlow } from '../../../../../test/factories/flow.js';
+import { createStep } from '../../../../../test/factories/step.js';
+import getFlowMock from '../../../../../test/mocks/rest/api/v1/flows/get-flow.js';
+import app from '../../../../app.js';
+import * as license from '../../../../helpers/license.ee.js';
+
+describe('GET /api/v1/flows/:flowId', () => {
+  let token;
+
+  beforeEach(async () => {
+    vi.spyOn(license, 'hasValidLicense').mockResolvedValue(true);
+
+    token = (await createApiToken()).token;
+  });
+
+  it('should return the flow data', async () => {
+    const flow = await createFlow();
+    const triggerStep = await createStep({ flowId: flow.id });
+    const actionStep = await createStep({ flowId: flow.id });
+
+    const response = await request(app)
+      .get(`/api/v1/flows/${flow.id}`)
+      .set('x-api-token', token)
+      .expect(200);
+
+    const expectedPayload = await getFlowMock(flow, [triggerStep, actionStep]);
+
+    expect(response.body).toStrictEqual(expectedPayload);
+  });
+
+  it('should return not found response for not existing flow UUID', async () => {
+    const notExistingFlowUUID = Crypto.randomUUID();
+
+    await request(app)
+      .get(`/api/v1/flows/${notExistingFlowUUID}`)
+      .set('x-api-token', token)
+      .expect(404);
+  });
+
+  it('should return bad request response for invalid UUID', async () => {
+    await request(app)
+      .get('/api/v1/flows/invalidFlowUUID')
+      .set('x-api-token', token)
+      .expect(400);
+  });
+});