Introduction
Koa is a new web framework designed by the team behind Express, +window.analytics.page();
Introduction
Koa is a new web framework designed by the team behind Express, which aims to be a smaller, more expressive, and more robust foundation for web applications and APIs. By leveraging async functions, Koa allows you to ditch callbacks and greatly increase error-handling. Koa does not bundle any @@ -9,25 +9,19 @@
Installation
Koa requires node v7.6.0 or higher for ES2015 and async function support.
You can quickly install a supported version of node with your favorite version manager:
-$ nvm install 7
+$ nvm install 7
$ npm i koa
-$ node my-koa-app.js
-
-Async Functions with Babel
+$ node my-koa-app.jsAsync Functions with Babel
To use async functions in Koa in versions of node < 7.6, we recommend using babel's require hook.
-require('babel-register');
-// require the rest of the app that needs to be transpiled after the hook
-const app = require('./app');
-
-To parse and transpile async functions,
+
require('babel-register');
+// require the rest of the app that needs to be transpiled after the hook
+const app = require('./app');
To parse and transpile async functions,
you should at a minimum have the transform-async-to-generator
or transform-async-to-module-method plugins.
For example, in your .babelrc file, you should have:
-{
- "plugins": ["transform-async-to-generator"]
-}
-
-You can also use the env preset with a target option "node": "current" instead.
+{
+ "plugins": ["transform-async-to-generator"]
+}
You can also use the env preset with a target option "node": "current" instead.
Application
A Koa application is an object containing an array of middleware functions
which are composed and executed in a stack-like manner upon request. Koa is similar to many
@@ -39,16 +33,34 @@
Application
among others. Despite supplying a reasonably large number of helpful methods Koa maintains a small footprint, as
no middleware are bundled.
The obligatory hello world application:
-const Koa = require('koa');
-const app = new Koa();
+
+const Koa = require('koa');
+const app = new Koa();
-app.use(async ctx => {
- ctx.body = 'Hello World';
+app.use(async ctx => {
+ ctx.body = 'Hello World';
});
-app.listen(3000);
-
-Cascading
+app.listen(3000);Cascading
Koa middleware cascade in a more traditional way as you may be used to with similar tools -
this was previously difficult to make user friendly with node's use of callbacks.
However with async functions we can achieve "true" middleware. Contrasting Connect's implementation which
@@ -60,35 +72,53 @@
Cascading
the function suspends and passes control to the next middleware defined. After there are no more
middleware to execute downstream, the stack will unwind and each middleware is resumed to perform
its upstream behaviour.
-const Koa = require('koa');
-const app = new Koa();
+
+const Koa = require('koa');
+const app = new Koa();
-// logger
+// logger
-app.use(async (ctx, next) => {
- await next();
- const rt = ctx.response.get('X-Response-Time');
- console.log(`${ctx.method} ${ctx.url} - ${rt}`);
+app.use(async (ctx, next) => {
+ await next();
+ const rt = ctx.response.get('X-Response-Time');
+ console.log(`${ctx.method} ${ctx.url} - ${rt}`);
});
-// x-response-time
+// x-response-time
-app.use(async (ctx, next) => {
- const start = Date.now();
- await next();
- const ms = Date.now() - start;
- ctx.set('X-Response-Time', `${ms}ms`);
+app.use(async (ctx, next) => {
+ const start = Date.now();
+ await next();
+ const ms = Date.now() - start;
+ ctx.set('X-Response-Time', `${ms}ms`);
});
-// response
+// response
-app.use(async ctx => {
- ctx.body = 'Hello World';
+app.use(async ctx => {
+ ctx.body = 'Hello World';
});
-app.listen(3000);
-
-Settings
+app.listen(3000);Settings
Application settings are properties on the app instance, currently
the following are supported:
@@ -102,26 +132,20 @@ app.listen(...)
applications with a single HTTP server.
Create and return an HTTP server, passing the given arguments to
Server#listen(). These arguments are documented on nodejs.org. The following is a useless Koa application bound to port 3000:
-
const Koa = require('koa');
-const app = new Koa();
-app.listen(3000);
-
- The app.listen(...) method is simply sugar for the following:
-const http = require('http');
-const Koa = require('koa');
-const app = new Koa();
-http.createServer(app.callback()).listen(3000);
-
- This means you can spin up the same application as both HTTP and HTTPS
+
const Koa = require('koa');
+const app = new Koa();
+app.listen(3000);
The app.listen(...) method is simply sugar for the following:
+const http = require('http');
+const Koa = require('koa');
+const app = new Koa();
+http.createServer(app.callback()).listen(3000);
This means you can spin up the same application as both HTTP and HTTPS
or on multiple addresses:
-const http = require('http');
-const https = require('https');
-const Koa = require('koa');
-const app = new Koa();
-http.createServer(app.callback()).listen(3000);
-https.createServer(app.callback()).listen(3001);
-
-app.callback()
+const http = require('http');
+const https = require('https');
+const Koa = require('koa');
+const app = new Koa();
+http.createServer(app.callback()).listen(3000);
+https.createServer(app.callback()).listen(3001);
app.callback()
Return a callback function suitable for the http.createServer()
method to handle a request.
You may also use this callback function to mount your Koa app in a
@@ -134,27 +158,21 @@
app.keys=
These are passed to KeyGrip,
however you may also pass your own KeyGrip instance. For
example the following are acceptable:
-app.keys = ['im a newer secret', 'i like turtle'];
-app.keys = new KeyGrip(['im a newer secret', 'i like turtle'], 'sha256');
-
- These keys may be rotated and are used when signing cookies
+
app.keys = ['im a newer secret', 'i like turtle'];
+app.keys = new KeyGrip(['im a newer secret', 'i like turtle'], 'sha256');
These keys may be rotated and are used when signing cookies
with the { signed: true } option:
-ctx.cookies.set('name', 'tobi', { signed: true });
-
-app.context
+ctx.cookies.set('name', 'tobi', { signed: true });
app.context
app.context is the prototype from which ctx is created.
You may add additional properties to ctx by editing app.context.
This is useful for adding properties or methods to ctx to be used across your entire app,
which may be more performant (no middleware) and/or easier (fewer require()s)
at the expense of relying more on ctx, which could be considered an anti-pattern.
For example, to add a reference to your database from ctx:
-app.context.db = db();
+app.context.db = db();
-app.use(async ctx => {
- console.log(ctx.db);
-});
-
-Note:
+app.use(async ctx => {
+ console.log(ctx.db);
+});Note:
- Many properties on
ctx are defined using getters, setters, and Object.defineProperty(). You can only edit these properties (not recommended) by using Object.defineProperty() on app.context. See https://github.com/koajs/koa/issues/652.
- Mounted apps currently use their parent's
ctx and settings. Thus, mounted apps are really just groups of middleware.
@@ -163,16 +181,12 @@ Error Handling
By default outputs all errors to stderr unless app.silent is true.
The default error handler also won't output errors when err.status is 404 or err.expose is true.
To perform custom error-handling logic such as centralized logging you can add an "error" event listener:
-
app.on('error', err => {
- log.error('server error', err)
-});
-
- If an error is in the req/res cycle and it is not possible to respond to the client, the Context instance is also passed:
-app.on('error', (err, ctx) => {
- log.error('server error', err, ctx)
-});
-
- When an error occurs and it is still possible to respond to the client, aka no data has been written to the socket, Koa will respond
+
app.on('error', err => {
+ log.error('server error', err)
+});
If an error is in the req/res cycle and it is not possible to respond to the client, the Context instance is also passed:
+app.on('error', (err, ctx) => {
+ log.error('server error', err, ctx)
+});
When an error occurs and it is still possible to respond to the client, aka no data has been written to the socket, Koa will respond
appropriately with a 500 "Internal Server Error". In either case
an app-level "error" is emitted for logging purposes.
Context
@@ -185,13 +199,11 @@Error Handling
A Context is created per request, and is referenced in middleware
as the receiver, or the ctx identifier, as shown in the following
snippet:
app.use(async ctx => {
- ctx; // is the Context
- ctx.request; // is a Koa Request
- ctx.response; // is a Koa Response
-});
- Many of the context's accessors and methods simply delegate to their ctx.request or ctx.response
+
app.use(async ctx => {
+ ctx; // is the Context
+ ctx.request; // is a Koa Request
+ ctx.response; // is a Koa Response
+}); Many of the context's accessors and methods simply delegate to their ctx.request or ctx.response
equivalents for convenience, and are otherwise identical. For example ctx.type and ctx.length
delegate to the response object, and ctx.path and ctx.method delegate to the request.
API
@@ -213,9 +225,7 @@ctx.response
A Koa Response object.
ctx.state
The recommended namespace for passing information through middleware and to your frontend views.
-ctx.state.user = await User.find(id);
-ctx.app
+ctx.state.user = await User.find(id);ctx.app
Application instance reference.
ctx.cookies.get(name, [options])
Get cookie name with options:
ctx.throw([status], [msg], [properties
Helper method to throw an error with a .status property
defaulting to 500 that will allow Koa to respond appropriately.
The following combinations are allowed:
ctx.throw(400);
-ctx.throw(400, 'name required');
-ctx.throw(400, 'name required', { user: user });
- For example ctx.throw(400, 'name required') is equivalent to:
const err = new Error('name required');
-err.status = 400;
-err.expose = true;
-throw err;
-Note that these are user-level errors and are flagged with +
ctx.throw(400);
+ctx.throw(400, 'name required');
+ctx.throw(400, 'name required', { user: user }); For example ctx.throw(400, 'name required') is equivalent to:
const err = new Error('name required');
+err.status = 400;
+err.expose = true;
+throw err; Note that these are user-level errors and are flagged with
err.expose meaning the messages are appropriate for
client responses, which is typically not the case for
error messages since you do not want to leak failure
details.
You may optionally pass a properties object which is merged into the error as-is, useful for decorating machine-friendly errors which are reported to the requester upstream.
ctx.throw(401, 'access_denied', { user: user });
-Koa uses http-errors to create errors.
+ctx.throw(401, 'access_denied', { user: user });Koa uses http-errors to create errors.
ctx.assert(value, [status], [msg], [properties])
Helper method to throw an error similar to .throw()
when !value. Similar to node's assert()
method.
ctx.assert(ctx.state.user, 401, 'User not found. Please login!');
-Koa uses http-assert for assertions.
+ctx.assert(ctx.state.user, 401, 'User not found. Please login!');Koa uses http-assert for assertions.
ctx.respond
To bypass Koa's built-in response handling, you may explicitly set ctx.respond = false;. Use this if you want to write to the raw res object instead of letting Koa handle the response for you.
Note that using this is not supported by Koa. This may break intended functionality of Koa middleware and Koa itself. Using this property is considered a hack and is only a convenience to those wishing to use traditional fn(req, res) functions and middleware within Koa.
request.originalUrl
Get request original URL.
request.origin
Get origin of URL, include protocol and host.
ctx.request.origin
-// => http://example.com
-request.href
+ctx.request.origin
+// => http://example.comrequest.href
Get full request URL, include protocol, host and url.
ctx.request.href;
-// => http://example.com/foo/bar?q=1
-request.path
+ctx.request.href;
+// => http://example.com/foo/bar?q=1request.path
Get request pathname.
request.path=
Set request pathname and retain query-string when present.
@@ -387,47 +385,37 @@request.URL
Get WHATWG parsed URL object.
request.type
Get request Content-Type void of parameters such as "charset".
const ct = ctx.request.type;
-// => "image/png"
-request.charset
+const ct = ctx.request.type;
+// => "image/png"request.charset
Get request charset when present, or undefined:
ctx.request.charset;
-// => "utf-8"
-request.query
+ctx.request.charset;
+// => "utf-8"request.query
Get parsed query-string, returning an empty object when no query-string is present. Note that this getter does not support nested parsing.
For example "color=blue&size=small":
-{
- color: 'blue',
- size: 'small'
-}
-request.query=
+{
+ color: 'blue',
+ size: 'small'
+}request.query=
Set query-string to the given object. Note that this setter does not support nested objects.
-ctx.query = { next: '/login' };
-request.fresh
+ctx.query = { next: '/login' };request.fresh
Check if a request cache is "fresh", aka the contents have not changed. This
method is for cache negotiation between If-None-Match / ETag, and If-Modified-Since and Last-Modified. It should be referenced after setting one or more of these response headers.
// freshness check requires status 20x or 304
-ctx.status = 200;
-ctx.set('ETag', '123');
+// freshness check requires status 20x or 304
+ctx.status = 200;
+ctx.set('ETag', '123');
-// cache is ok
-if (ctx.fresh) {
- ctx.status = 304;
- return;
+// cache is ok
+if (ctx.fresh) {
+ ctx.status = 304;
+ return;
}
-// cache is stale
-// fetch new data
-ctx.body = await db.find('something');
-
-request.stale
+// cache is stale
+// fetch new data
+ctx.body = await db.find('something');request.stale
Inverse of request.fresh.
request.protocol
Return request protocol, "https" or "http". Supports X-Forwarded-Proto
@@ -456,27 +444,23 @@
request.is(types...)
If there is no request body, null is returned.
If there is no content type, or the match fails false is returned.
Otherwise, it returns the matching content-type.
-// With Content-Type: text/html; charset=utf-8
-ctx.is('html'); // => 'html'
-ctx.is('text/html'); // => 'text/html'
-ctx.is('text/*', 'text/html'); // => 'text/html'
+// With Content-Type: text/html; charset=utf-8
+ctx.is('html'); // => 'html'
+ctx.is('text/html'); // => 'text/html'
+ctx.is('text/*', 'text/html'); // => 'text/html'
-// When Content-Type is application/json
-ctx.is('json', 'urlencoded'); // => 'json'
-ctx.is('application/json'); // => 'application/json'
-ctx.is('html', 'application/*'); // => 'application/json'
+// When Content-Type is application/json
+ctx.is('json', 'urlencoded'); // => 'json'
+ctx.is('application/json'); // => 'application/json'
+ctx.is('html', 'application/*'); // => 'application/json'
-ctx.is('html'); // => false
-
- For example if you want to ensure that
+ctx.is('html'); // => false
For example if you want to ensure that
only images are sent to a given route:
-if (ctx.is('image/*')) {
- // process
-} else {
- ctx.throw(415, 'images only!');
-}
-
-Content Negotiation
+if (ctx.is('image/*')) {
+ // process
+} else {
+ ctx.throw(415, 'images only!');
+}
Content Negotiation
Koa's request object includes helpful content negotiation utilities powered by accepts and negotiator. These utilities are:
request.accepts(types)request.accepts(types)
Check if the given type(s) is acceptable, returning the best match when true, otherwise false. The type value may be one or more mime type string
such as "application/json", the extension name
such as "json", or an array ["json", "html", "text/plain"].
-
// Accept: text/html
-ctx.accepts('html');
-// => "html"
+// Accept: text/html
+ctx.accepts('html');
+// => "html"
-// Accept: text/*, application/json
-ctx.accepts('html');
-// => "html"
-ctx.accepts('text/html');
-// => "text/html"
-ctx.accepts('json', 'text');
-// => "json"
-ctx.accepts('application/json');
-// => "application/json"
+// Accept: text/*, application/json
+ctx.accepts('html');
+// => "html"
+ctx.accepts('text/html');
+// => "text/html"
+ctx.accepts('json', 'text');
+// => "json"
+ctx.accepts('application/json');
+// => "application/json"
-// Accept: text/*, application/json
-ctx.accepts('image/png');
-ctx.accepts('png');
-// => false
+// Accept: text/*, application/json
+ctx.accepts('image/png');
+ctx.accepts('png');
+// => false
-// Accept: text/*;q=.5, application/json
-ctx.accepts(['html', 'json']);
-ctx.accepts('html', 'json');
-// => "json"
+// Accept: text/*;q=.5, application/json
+ctx.accepts(['html', 'json']);
+ctx.accepts('html', 'json');
+// => "json"
-// No Accept header
-ctx.accepts('html', 'json');
-// => "html"
-ctx.accepts('json', 'html');
-// => "json"
-
- You may call ctx.accepts() as many times as you like,
+// No Accept header
+ctx.accepts('html', 'json');
+// => "html"
+ctx.accepts('json', 'html');
+// => "json"
You may call ctx.accepts() as many times as you like,
or use a switch:
-switch (ctx.accepts('json', 'html', 'text')) {
- case 'json': break;
- case 'html': break;
- case 'text': break;
- default: ctx.throw(406, 'json, html, or text only');
-}
-
-request.acceptsEncodings(encodings)
+switch (ctx.accepts('json', 'html', 'text')) {
+ case 'json': break;
+ case 'html': break;
+ case 'text': break;
+ default: ctx.throw(406, 'json, html, or text only');
+}
request.acceptsEncodings(encodings)
Check if encodings are acceptable, returning the best match when true, otherwise false. Note that you should include identity as one of the encodings!
-// Accept-Encoding: gzip
-ctx.acceptsEncodings('gzip', 'deflate', 'identity');
-// => "gzip"
+// Accept-Encoding: gzip
+ctx.acceptsEncodings('gzip', 'deflate', 'identity');
+// => "gzip"
-ctx.acceptsEncodings(['gzip', 'deflate', 'identity']);
-// => "gzip"
-
- When no arguments are given all accepted encodings
+ctx.acceptsEncodings(['gzip', 'deflate', 'identity']);
+// => "gzip"
When no arguments are given all accepted encodings
are returned as an array:
-// Accept-Encoding: gzip, deflate
+// Accept-Encoding: gzip, deflate
ctx.acceptsEncodings();
-// => ["gzip", "deflate", "identity"]
-
- Note that the identity encoding (which means no encoding) could be unacceptable if the client explicitly sends identity;q=0. Although this is an edge case, you should still handle the case where this method returns false.
+// => ["gzip", "deflate", "identity"] Note that the identity encoding (which means no encoding) could be unacceptable if the client explicitly sends identity;q=0. Although this is an edge case, you should still handle the case where this method returns false.
request.acceptsCharsets(charsets)
Check if charsets are acceptable, returning
the best match when true, otherwise false.
-// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
-ctx.acceptsCharsets('utf-8', 'utf-7');
-// => "utf-8"
+// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
+ctx.acceptsCharsets('utf-8', 'utf-7');
+// => "utf-8"
-ctx.acceptsCharsets(['utf-7', 'utf-8']);
-// => "utf-8"
-
- When no arguments are given all accepted charsets
+ctx.acceptsCharsets(['utf-7', 'utf-8']);
+// => "utf-8"
When no arguments are given all accepted charsets
are returned as an array:
-// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
+// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
ctx.acceptsCharsets();
-// => ["utf-8", "utf-7", "iso-8859-1"]
-
-request.acceptsLanguages(langs)
+// => ["utf-8", "utf-7", "iso-8859-1"]request.acceptsLanguages(langs)
Check if langs are acceptable, returning
the best match when true, otherwise false.
-// Accept-Language: en;q=0.8, es, pt
-ctx.acceptsLanguages('es', 'en');
-// => "es"
+// Accept-Language: en;q=0.8, es, pt
+ctx.acceptsLanguages('es', 'en');
+// => "es"
-ctx.acceptsLanguages(['en', 'es']);
-// => "es"
-
- When no arguments are given all accepted languages
+ctx.acceptsLanguages(['en', 'es']);
+// => "es"
When no arguments are given all accepted languages
are returned as an array:
-// Accept-Language: en;q=0.8, es, pt
+// Accept-Language: en;q=0.8, es, pt
ctx.acceptsLanguages();
-// => ["es", "pt", "en"]
-
-request.idempotent
+// => ["es", "pt", "en"]request.idempotent
Check if the request is idempotent.
request.socket
Return the request socket.
@@ -698,48 +666,34 @@ Stream
For example, you may not want this when setting the body as an HTTP stream in a proxy as it would destroy the underlying connection.
See: https://github.com/koajs/koa/pull/612 for more information.
Here's an example of stream error handling without automatically destroying the stream:
-const PassThrough = require('stream').PassThrough;
+const PassThrough = require('stream').PassThrough;
-app.use(async ctx => {
- ctx.body = someHTTPStream.on('error', ctx.onerror).pipe(PassThrough());
-});
-
-Object
+app.use(async ctx => {
+ ctx.body = someHTTPStream.on('error', ctx.onerror).pipe(PassThrough());
+});Object
The Content-Type is defaulted to application/json. This includes plain objects { foo: 'bar' } and arrays ['foo', 'bar'].
response.get(field)
Get a response header field value with case-insensitive field.
-const etag = ctx.response.get('ETag');
-
-response.set(field, value)
+const etag = ctx.response.get('ETag');
response.set(field, value)
Set response header field to value:
-ctx.set('Cache-Control', 'no-cache');
-
-response.append(field, value)
+ctx.set('Cache-Control', 'no-cache');
response.append(field, value)
Append additional header field with value val.
-ctx.append('Link', '<http://127.0.0.1/>');
-
-response.set(fields)
+ctx.append('Link', '<http://127.0.0.1/>');
response.set(fields)
Set several response header fields with an object:
-ctx.set({
- 'Etag': '1234',
- 'Last-Modified': date
-});
-
-response.remove(field)
+ctx.set({
+ 'Etag': '1234',
+ 'Last-Modified': date
+});
response.remove(field)
Remove header field.
response.type
Get response Content-Type void of parameters such as "charset".
-const ct = ctx.type;
-// => "image/png"
-
-response.type=
+const ct = ctx.type;
+// => "image/png"
response.type=
Set response Content-Type via mime string or file extension.
-ctx.type = 'text/plain; charset=utf-8';
-ctx.type = 'image/png';
-ctx.type = '.png';
-ctx.type = 'png';
-
- Note: when appropriate a charset is selected for you, for
+
ctx.type = 'text/plain; charset=utf-8';
+ctx.type = 'image/png';
+ctx.type = '.png';
+ctx.type = 'png';
Note: when appropriate a charset is selected for you, for
example response.type = 'html' will default to "utf-8". If you need to overwrite charset,
use ctx.set('Content-Type', 'text/html') to set response header field to value directly.
response.is(types...)
@@ -749,37 +703,31 @@ response.is(types...)
manipulate responses.
For example, this is a middleware that minifies
all HTML responses except for streams.
-const minify = require('html-minifier');
+const minify = require('html-minifier');
-app.use(async (ctx, next) => {
- await next();
+app.use(async (ctx, next) => {
+ await next();
- if (!ctx.response.is('html')) return;
+ if (!ctx.response.is('html')) return;
- let body = ctx.body;
- if (!body || body.pipe) return;
+ let body = ctx.body;
+ if (!body || body.pipe) return;
- if (Buffer.isBuffer(body)) body = body.toString();
+ if (Buffer.isBuffer(body)) body = body.toString();
ctx.body = minify(body);
-});
-
-response.redirect(url, [alt])
+});response.redirect(url, [alt])
Perform a [302] redirect to url.
The string "back" is special-cased
to provide Referrer support, when Referrer
is not present alt or "/" is used.
-ctx.redirect('back');
-ctx.redirect('back', '/index.html');
-ctx.redirect('/login');
-ctx.redirect('http://google.com');
-
- To alter the default status of 302, simply assign the status
+
ctx.redirect('back');
+ctx.redirect('back', '/index.html');
+ctx.redirect('/login');
+ctx.redirect('http://google.com');
To alter the default status of 302, simply assign the status
before or after this call. To alter the body, assign it after this call:
-ctx.status = 301;
-ctx.redirect('/cart');
-ctx.body = 'Redirecting to shopping cart';
-
-response.attachment([filename])
+ctx.status = 301;
+ctx.redirect('/cart');
+ctx.body = 'Redirecting to shopping cart';
response.attachment([filename])
Set Content-Disposition to "attachment" to signal the client
to prompt for download. Optionally specify the filename of the
download.
@@ -791,18 +739,14 @@ response.lastModified
response.lastModified=
Set the Last-Modified header as an appropriate UTC string.
You can either set it as a Date or date string.
-ctx.response.lastModified = new Date();
-
-response.etag=
+ctx.response.lastModified = new Date();
response.etag=
Set the ETag of a response including the wrapped "s.
Note that there is no corresponding response.etag getter.
-ctx.response.etag = crypto.createHash('md5').update(ctx.body).digest('hex');
-
-response.vary(field)
+ctx.response.etag = crypto.createHash('md5').update(ctx.body).digest('hex');
response.vary(field)
Vary on field.
response.flushHeaders()
Flush any set headers, and begin the body.
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Links
Community links to discover third-party middleware for Koa, full runnable examples, thorough guides and more! If you have questions join us in IRC! -
- GitHub repository
- Examples
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- G+ Community
- Mailing list
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- #koajs on freenode
- GitHub repository
- Examples
- Middleware
- Wiki
- G+ Community
- Mailing list
- Guide
- FAQ
- #koajs on freenode