first implementation for Koa support

README.md

@@ -25,7 +25,7 @@ defined in the [healthcheck draft RFC](https://tools.ietf.org/html/draft-inadare
 ### Immediate Priority
 
 - [x] Express/Connect
-- [ ] Koa
+- [x] Koa
 - [ ] Pure Node, no frameworks
 
 ### Open to Community Contributions
@@ -43,13 +43,16 @@ defined in the [healthcheck draft RFC](https://tools.ietf.org/html/draft-inadare
 
 ## Usage
 
+### Examples for Express.js
+
 Basic Usage:
 
 ```javascript
 const healthcheck = require('maikai');
 
 // Add middleware to your Express app:
 app.use(healthcheck().express());
+app.listen(3535);
 ```
 
 Advanced usage with custom health checker:
@@ -73,6 +76,20 @@ check.addCheck('cassandra', 'timeout', async () => {
 
 // Add middleware to your Express app:
 app.use(check.express());
+app.listen(3535);
+```
+
+### Example for Koa.js
+
+```javascript
+const Koa = require('koa');
+const app = new Koa();
+const healthcheck = require("../");
+
+const check = healthcheck();
+
+app.use(check.koa());
+app.listen(3535);
 ```
 
 ## Kubernetes Liveness and Readiness Probes

examples/serverKoa.js

@@ -1,18 +1,23 @@
 const Koa = require('koa');
 const app = new Koa();
+const healthcheck = require("../");
 
-app.use(koaMiddleWare);
-
-// response
-app.use(ctx => {
-  ctx.body = 'Hello Koa';
+const check = healthcheck();
+check.addCheck('cassandra', 'timeout', async() => {
+    return {
+        status : 'pass',
+        bullshit : false,
+        metricValue: 250,
+        "metricUnit": "ms"
+    };
 });
 
-app.listen(3535);
+app.use(check.koa());
+
+const check2 = healthcheck({"path" : "/ping"});
+app.use(check2.koa());
+
+app.listen(3535, () => console.log('Example app listening on port 3535!'));
+
+//app.listen(3535);
 
-async function koaMiddleWare(ctx, next) {
-  if (ctx.request.originalUrl != '/health') return next();
-  ctx.set('Content-Type', `application/json`);
-  ctx.response.status = 201;
-  ctx.body= {"name" : "response"};
-}

lib/health.js

@@ -40,9 +40,11 @@ class HealthCheck {
       const response = await this.healthResponse(this.opts);
       const httpCode = (response.status === STATUS_ERR ) ? 503 : 200;
 
-      ctx.set('Content-Type', 'application/health+json');
+
       ctx.response.status = httpCode;
       ctx.body= response;
+      // Make sure this comes after ctx.body : https://github.com/koajs/koa/issues/1120
+      ctx.set('Content-Type', 'application/health+json; charset=utf-8');
     };
   }  
 

test/acceptance/express-basic-test.js

@@ -2,7 +2,7 @@ const test = require('blue-tape');
 const nf = require('node-fetch');
 const log  = require('metalogger')();
 
-test('Basic Healthy Health Check', async t => {
+test('Basic Healthy Express Health Check', async t => {
 
   // avoid problems if this env var is already set from wherever test was run
   process.env.NODE_HEALTH_ENDPOINT_PATH = "";

test/acceptance/express-failing-check-basic-test.js

@@ -2,7 +2,7 @@ const test = require('blue-tape');
 const nf = require('node-fetch');
 const log  = require('metalogger')();
 
-test('Failing Health Check', async t => {
+test('Failing Express Health Check', async t => {
   const brokenserver = require('../support/failing-check-server').server;
   try {
     const util = require('../support/util');

test/acceptance/express-unknown-response-status-test.js

@@ -1,7 +1,7 @@
 const test = require('blue-tape');
 const nf = require('node-fetch');
 
-test('Unknown Response Status From a Dependency', async t => {
+test('Unknown Express Response Status From a Dependency', async t => {
   const server = getServer();
   try {
     const util = require('../support/util');

test/acceptance/koa-basic-test.js

@@ -0,0 +1,61 @@
+const test = require('blue-tape');
+const nf = require('node-fetch');
+
+test('Basic Healthy Koa Health Check', async t => {
+
+  // avoid problems if this env var is already set from wherever test was run
+  process.env.NODE_HEALTH_ENDPOINT_PATH = "";
+
+  const server = getServer();
+  const util = require('../support/util');
+  const baseuri = util.serverUri(server);
+
+  try {
+    const res = await nf(`${baseuri}/hello`);
+
+    const res2 = await nf(`${baseuri}/health`);  
+    t.equal(res2.status, 200, 'proper http status code for /health');
+    t.equal(res2.headers.get('content-type'), 
+            'application/health+json; charset=utf-8',
+            'proper content type for health endpoint');
+    const response = await res2.json();
+    t.same(response.status, 'pass',
+      'healthcheck endpoint status works');
+    //t.same(response.details["cassandra:timeout"].metricUnit, 'ms',
+    //  'healthcheck endpoint details work');
+
+  } catch (err) {
+    t.fail(err);
+  }
+
+  server.close();
+
+});
+
+function getServer() {
+  const http = require('http');
+  const Koa = require('koa');
+  const app = new Koa();
+
+  const healthcheck  = require('../../lib/health')();
+
+  healthcheck.addCheck('backend', 'koa-downstream', async() => {
+    return {
+        status : 'pass',
+        metricValue: 17,
+        metricUnit: "units"
+    };
+  });
+
+  app.use(healthcheck.koa());
+
+  const server = http.createServer(app.callback());
+
+  server.listen(0, function(err) {
+    if (err) console.error(err) && process.exit(1);
+    const port = server.address().port;
+    //console.log(`Test server listening at port ${port} \n`);
+  });
+
+  return server;
+}

test/acceptance/path-override-test.js

@@ -2,7 +2,7 @@ const test = require('blue-tape');
 const nf = require('node-fetch');
 const log  = require('metalogger')();
 
-test('Overriding health endpoint URI', async t => {
+test('Overriding Express health endpoint URI', async t => {
 
   const OVERRIDDEN_PATH = "/ping";
   process.env.NODE_HEALTH_ENDPOINT_PATH = OVERRIDDEN_PATH;