More progress on simple plugin system

Author: mitchmac

.github/workflows/e2e.yml

@@ -15,4 +15,10 @@ jobs:
       - run: ./run-test.sh
         working-directory: ./tests/e2e
 
-      - run: curl -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/hi"}'
+      - run: curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php"}' | grep -q '{"statusCode":200,"headers"'
+
+      - run: curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php", "postRequestPlugin": "1"}' | grep -q '{"statusCode":201,"body":"Foo"}'
+
+      - run: curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php", "preRequestPlugin": "1"}' | grep -q '{"statusCode":200,"body":"Foo"}'
+
+      - run: curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/static.css"}' | grep -q 'background-color: blue'

package.json

@@ -26,6 +26,7 @@
     "jest": "^29.5.0"
   },
   "scripts": {
-    "test": "jest --testPathIgnorePatterns 'e2e'"
+    "test": "jest --testPathIgnorePatterns 'e2e'",
+    "local-tests": "npm run test && cd tests/e2e && ./local.sh"
   }
 }

src/index.js

@@ -21,6 +21,11 @@ async function handler(data) {
     await validate(data);
 
     const { event, docRoot } = data;
+
+    const preRequestResponse = await plugins.executePreRequest(event);
+    if (preRequestResponse !== null) {
+        return preRequestResponse;
+    }
 
     if (!php) {
         const env = {
@@ -208,7 +213,7 @@ async function handler(data) {
             returnResponse.multiValueHeaders = multiHeaders;
         }
 
-        return returnResponse;
+        return await plugins.executePostRequest(event, returnResponse);
     }
     catch (err) {
         console.log(err);

src/plugins.js

@@ -1,7 +1,16 @@
 let plugins = [];
 
 function register(plugin) {
-    //@TODO: validate the plugin
+    // Require a plugin name.
+    if (!plugin.hasOwnProperty("name") || !plugin.name) {
+        throw new Error("Plugins are required to have a name");
+    }
+
+    // Don't allow double registration.
+    if (plugins.find((plug) => plug.name === plugin.name)) {
+        throw new Error("Plugins can only be registered once");
+    }
+
     plugins.push(plugin);
 }
 
@@ -19,18 +28,25 @@ async function executePreRequest(event) {
         }
     }
 
+    //@TODO: validate response
     return response;
 }
 
 async function executePostRequest(event, response) {
     //@TODO: only loop through plugins with postRequest.
     for (let i = 0; i < plugins.length; i++) {
         let plugin = plugins[i];
+        let pluginResponse;
+
         if (plugin.postRequest) {
-            response = await plugin.postRequest(event, response);
+            pluginResponse = await plugin.postRequest(event, response);
+            if (pluginResponse) {
+                response = pluginResponse;
+            }
         }
     }
 
+    //@TODO: validate response
     return response;
 }
 

tests/e2e/local.sh

@@ -4,9 +4,13 @@
 
 docker run -p 9000:8080 -d --name serverlesswp-local docker-lambda-serverlesswp
 
-curl -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php"}'
+curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php"}' | grep -q '{"statusCode":200,"headers"'
 
-curl -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/static.css"}'
+curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php", "postRequestPlugin": "1"}' | grep -q '{"statusCode":201,"body":"Foo"}'
+
+curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/index.php", "preRequestPlugin": "1"}' | grep -q '{"statusCode":200,"body":"Foo"}'
+
+curl -s -XPOST "http://localhost:9000/2015-03-31/functions/function/invocations" -d '{"path":"/static.css"}' | grep -q 'background-color: blue'
 
 docker stop serverlesswp-local
 docker rm serverlesswp-local

tests/e2e/test.js

@@ -1,6 +1,32 @@
 const serverlesswp = require('./src/index');
 const path = require('path');
 
+serverlesswp.registerPlugin({
+    name: 'postRequest',
+    postRequest: async function(event, pluginResponse) {
+        // Bypass this plugin conditionally
+        if (event.postRequestPlugin) {
+            return {
+                statusCode: pluginResponse.statusCode + 1,
+                body: 'Foo'
+            }
+        }
+    }
+});
+
+serverlesswp.registerPlugin({
+    name: 'preRequest',
+    preRequest: async function(event) {
+        // Bypass this plugin conditionally
+        if (event.preRequestPlugin) {
+            return {
+                statusCode: 200,
+                body: 'Foo'
+            }
+        }
+    }
+});
+
 exports.handler = async function (event, context, callback) {
     const docRoot = path.join(process.cwd(), 'wp');
     const routerScript = path.join(process.cwd(), 'router.php');

tests/plugins.test.js

@@ -8,6 +8,16 @@ test('Plugin registration', () => {
     expect(pluginList).toHaveLength(2);
 });
 
+test('Plugins need a name', () => {
+    expect(() => { plugins.register({}) }).toThrow();
+    expect(() => { plugins.register({name: ''}) }).toThrow();
+});
+
+test('Plugins can only be registered once', () => {
+    plugins.register({name: 'baz'});
+    expect(() => { plugins.register({name: 'baz'}) }).toThrow();
+});
+
 test('Do not execute non-existent preRequest', async () => {
     plugins.register({name: 'Test'});