feat: add tests for mailer plugin (#222)

packages/mailer/package.json

@@ -13,12 +13,15 @@
   "main": "./dist/dzangolab-fastify-mailer.umd.cjs",
   "module": "./dist/dzangolab-fastify-mailer.js",
   "types": "./dist/types/index.d.ts",
-  "files": ["dist"],
+  "files": [
+    "dist"
+  ],
   "scripts": {
     "build": "vite build && tsc --emitDeclarationOnly && mv dist/src dist/types",
     "lint": "eslint . --ext .js,.jsx,.cjs,.mjs,.ts,.tsx,.cts,.mts --ignore-path .gitignore",
     "lint:fix": "eslint . --ext .js,.jsx,.cjs,.mjs,.ts,.tsx,.cts,.mts --fix --ignore-path .gitignore",
     "sort-package": "npx sort-package-json",
+    "test": "vitest run --coverage",
     "typecheck": "tsc --noEmit -p tsconfig.json --composite false"
   },
   "dependencies": {
@@ -37,6 +40,7 @@
     "@types/nodemailer-html-to-text": "3.1.0",
     "@typescript-eslint/eslint-plugin": "5.50.0",
     "@typescript-eslint/parser": "5.50.0",
+    "@vitest/coverage-istanbul": "0.28.4",
     "eslint": "8.33.0",
     "eslint-config-custom": "0.17.1",
     "fastify": "4.10.2",
@@ -45,10 +49,11 @@
     "prettier": "2.8.3",
     "tsconfig": "0.17.1",
     "typescript": "4.9.5",
-    "vite": "4.1.1"
+    "vite": "4.1.1",
+    "vitest": "0.28.4"
   },
   "peerDependencies": {
-    "@dzangolab/fastify-config": "0.17.1",
+    "@dzangolab/fastify-config": ">=0.17.1",
     "fastify": ">=4.9.2",
     "fastify-plugin": ">=4.3.0",
     "mjml": ">=4.13.0"

packages/mailer/src/__test__/helpers/createMailerConfig.ts

@@ -0,0 +1,24 @@
+const createMailerConfig = () => {
+  return {
+    mailer: {
+      defaults: {
+        from: {
+          address: "sender@example.com",
+          name: "Mailer Team",
+        },
+      },
+      test: { enabled: true, path: "/test/email", to: "receiver@example.com" },
+      templating: { templateFolder: "mjml/templates" },
+      templateData: { exampleUrl: "http://localhost:2000/" },
+      transport: {
+        auth: { pass: "pass", user: "user" },
+        host: "localhost",
+        port: 20073,
+        requireTLS: false,
+        secure: false,
+      },
+    },
+  };
+};
+
+export default createMailerConfig;

packages/mailer/src/__test__/mailer.spec.ts

@@ -0,0 +1,89 @@
+import fastify from "fastify";
+import { describe, expect, it, vi, beforeEach } from "vitest";
+
+import createMailerConfig from "./helpers/createMailerConfig";
+
+import type { FastifyInstance } from "fastify";
+
+const nodemailerMjmlPluginMock = vi.fn();
+const htmlToTextMock = vi.fn();
+const useMock = vi.fn();
+const sendMailMock = vi.fn().mockImplementation((config, callback) => {
+  callback();
+});
+const createTransportMock = vi.fn().mockReturnValue({
+  sendMail: sendMailMock,
+  use: useMock,
+});
+
+vi.mock("nodemailer", () => ({
+  createTransport: createTransportMock,
+}));
+
+vi.mock("nodemailer-mjml", () => ({
+  nodemailerMjmlPlugin: nodemailerMjmlPluginMock,
+}));
+
+vi.mock("nodemailer-html-to-text", () => ({
+  htmlToText: htmlToTextMock,
+}));
+
+describe("Mailer", async () => {
+  let api: FastifyInstance;
+
+  /* eslint-disable-next-line node/no-unsupported-features/es-syntax */
+  const { default: plugin } = await import("../plugin");
+
+  beforeEach(async () => {
+    api = await fastify();
+
+    api.decorate("config", createMailerConfig());
+  });
+
+  it("Create Mailer instance with ", async () => {
+    const { transport, defaults, templating } = createMailerConfig().mailer;
+    await api.register(plugin);
+
+    expect(createTransportMock).toHaveBeenCalledWith(transport, defaults);
+
+    expect(useMock).toHaveBeenCalledWith("compile", nodemailerMjmlPluginMock());
+
+    expect(useMock).toHaveBeenCalledWith("compile", htmlToTextMock());
+
+    expect(nodemailerMjmlPluginMock).toHaveBeenCalledWith({
+      templateFolder: templating.templateFolder,
+    });
+  });
+
+  it("Should throw error if mailer already registerd to api", async () => {
+    await api.register(plugin);
+
+    await expect(api.register(plugin)).rejects.toThrowError(
+      "fastify-mailer has already been registered"
+    );
+  });
+
+  it("Should call SendMail method ", async () => {
+    const {
+      templateData,
+      test: { path, to },
+    } = createMailerConfig().mailer;
+
+    await api.register(plugin);
+
+    await api.inject({
+      method: "GET",
+      path: path,
+    });
+
+    expect(sendMailMock).toHaveBeenCalledWith(
+      {
+        html: expect.stringContaining("<!doctype html>"),
+        subject: "test email",
+        to: to,
+        templateData: templateData,
+      },
+      expect.any(Function)
+    );
+  });
+});

packages/mailer/tsconfig.json

@@ -1,9 +1,9 @@
 {
   "extends": "tsconfig/base.json",
+  "exclude": ["src/**/__test__/**/*"],
   "compilerOptions": {
-    "outDir": "./dist",
+    "baseUrl": "./",
+    "outDir": "./dist"
   },
-  "include": [
-    "src/**/*.ts"
-  ]
+  "include": ["src/**/*.ts"]
 }

packages/mailer/vite.config.ts

@@ -45,5 +45,16 @@ export default defineConfig(({ mode }) => {
       },
       target: "es2022",
     },
+    resolve: {
+      alias: {
+        "@/": new URL("src/", import.meta.url).pathname,
+      },
+    },
+    test: {
+      coverage: {
+        provider: "istanbul",
+        reporter: ["text", "json", "html"],
+      },
+    },
   };
 });