express 0.1.6 express: ^0.1.6 copied to clipboard
A thin express-js inspired layer around Darts primitive HttpServer APIs with JSON and Jade HTML view engine support
Dart Express #
A simple, thin expressjs inspired layer around Dart's primitive HttpServer APIs. Also included is a single static file server module.
This library will eventually expand to help with other common usage patterns and features as and when needed.
Installing via Pub #
Add this to your package's pubspec.yaml file:
dependencies:
express: 0.1.6
Example Usages #
Basic Jade and Express app #
import "package:jaded/jaded.dart";
import "package:express/express.dart";
import "dart:io";
import "views/jade.views.dart" as views;
import "public/jade.views.dart" as pages;
main(){
int counter = 0;
var app = new Express()
..use(new JadeViewEngine(views.JADE_TEMPLATES, pages:pages.JADE_TEMPLATES))
..use(new StaticFileHandler("public"))
..get('/', (ctx){
ctx.render('index', {'title': 'Home'});
})
..get('/error', (ctx){
throw new ArgumentError("custom error in handler");
})
..get('/counter', (ctx){
ctx.sendJson({'counter': counter++});
});
app.listen("127.0.0.1", 8000);
}
Static files used by this app
- /public
/stylesheets
- style.css
- layout.jade - layout for .jade pages called directly (i.e. no explicit route required)
- layout-plain.jade - an alternative layout used by page.jade
- static.jade - a static home page
- page.jade - another page with layout-plain and inline :markdown content
- links.md - a markdown partial
- jade.yaml - tell express to watch and pre-compile .jade views in this directory
- jade.views.dart - the auto-generated pre-compiled .jade views for this directory
- /views
- layout.jade
- index.jade
- links.md - a markdown partial
- jade.yaml - tell express to watch and pre-compile .jade views in this directory
- jade.views.dart - the auto-generated pre-compiled .jade views for this directory
Pre-compile .jade views on save #
This example uses the Dart Editor build.dart
Build System to compile all .jade views in any directory that contains an empty jade.yaml
file.
To trigger this in your project add this to your projects /build.dart
file:
import "package:express/express_build.dart" as express;
main(){
express.build();
}
Backbone Todo's JSON Server #
This is an example of an Redis-powered REST backend Backbones.js demo TODO application:
var client = new RedisClient();
var app = new Express();
app
.use(new StaticFileHandler())
.get("/todos", (HttpContext ctx){
redis.keys("todo:*").then((keys) =>
redis.mget(keys).then(ctx.sendJson)
);
})
.get("/todos/:id", (HttpContext ctx){
var id = ctx.params["id"];
redis.get("todo:$id").then((todo) =>
todo != null ?
ctx.sendJson(todo) :
ctx.notFound("todo $id does not exist")
);
})
.post("/todos", (HttpContext ctx){
ctx.readAsJson().then((x){
redis.incr("ids:todo").then((newId){
var todo = $(x).defaults({"content":null,"done":false,"order":0});
todo["id"] = newId;
redis.set("todo:$newId", todo);
ctx.sendJson(todo);
});
});
})
.put("/todos/:id", (HttpContext ctx){
var id = ctx.params["id"];
ctx.readAsJson().then((todo){
redis.set("todo:$id", todo);
ctx.sendJson(todo);
});
})
.delete("/todos/:id", (HttpContext ctx){
redis.del("todo:${ctx.params['id']}");
ctx.send();
});
app.listen("127.0.0.1", 8000);
API #
Register encapsulated Modules like StaticFileHandler
abstract class Module {
void register(Express server);
}
The signature your Request Handlers should implement:
typedef void RequestHandler (HttpContext ctx);
The core Express API where all your Apps modules and request handlers are registered on. Then when the server has started, the request handler of the first matching route found will be executed.
abstract class Express {
factory Express() = _Express;
//Sets a config setting
void config(String name, String value);
//Gets a config setting
String getConfig(String name);
//Register a module to be used with this app
Express use(Module module);
//Register a request handler that will be called for a matching GET request
Express get(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching POST request
Express post(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching PUT request
Express put(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching DELETE request
Express delete(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching PATCH request
Express patch(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching HEAD request
Express head(String atRoute, RequestHandler handler);
//Register a request handler that will be called for a matching OPTIONS request
Express options(String atRoute, RequestHandler handler);
//Register a request handler that handles ANY verb
Express any(String atRoute, RequestHandler handler);
//Register a custom request handler. Execute requestHandler, if matcher is true.
//If priority < 0, custom handler will be executed before route handlers, otherwise after.
void addRequestHandler(bool matcher(HttpRequest req), void requestHandler(HttpContext ctx), {int priority:0});
//Alias for registering a request handler matching ANY verb
void operator []=(String atRoute, RequestHandler handler);
//Can any of the registered routes handle this HttpRequest
bool handlesRequest(HttpRequest req);
// Return true if this HttpRequest is a match for this verb and route
bool isMatch(String verb, String route, HttpRequest req);
// When all routes and modules are registered - Start the HttpServer on host:port
Future<HttpServer> listen([String host, int port]);
//render a view
void render(HttpContext ctx, String viewName, [dynamic viewModel]);
/// Permanently stops this [HttpServer] from listening for new connections.
/// This closes this [Stream] of [HttpRequest]s with a done event.
void close();
}
A high-level object encapsulating both HttpRequest and HttpResponse objects providing useful overloads for common operations and usage patterns.
abstract class HttpContext implements HttpRequest {
//Context
String routePath;
HttpRequest req;
HttpResponse res;
Map<String,String> get params;
//Read APIs
String get contentType;
Future<List<int>> readAsBytes();
Future<String> readAsText([Encoding encoding]);
Future<Object> readAsJson({Encoding encoding});
Future<Object> readAsObject([Encoding encoding]);
//Write APIs
String get responseContentType;
void set responseContentType(String value);
HttpContext head([int httpStatus, String statusReason, String contentType, Map<String,String> headers]);
HttpContext write(Object value, {String contentType});
HttpContext writeText(String text);
HttpContext writeBytes(List<int> bytes);
//Overloads for sending different content responses
void send({Object value, String contentType, int httpStatus, String statusReason});
void sendJson(Object value, {int httpStatus, String statusReason});
void sendHtml(Object value, [int httpStatus, String statusReason]);
void sendText(Object value, {String contentType, int httpStatus, String statusReason});
void sendBytes(List<int> bytes, {String contentType, int httpStatus, String statusReason});
//Custom Status responses
void notFound([String statusReason, Object value, String contentType]);
//Format response with the default renderer
void render(String, [dynamic viewModel]);
//Close and mark this request as handled
void end();
//If the request has been handled
bool get closed;
}
Modules #
JadeViewEngine #
Register the jaded view engine to render HTML .jade views. Supports both controller view pages and static page .jade templates.
app.use(new JadeViewEngine(views.JADE_TEMPLATES, pages:pages.JADE_TEMPLATES))
Usage
app.get('/', (HttpContext ctx){
ctx.render('index', {'title': 'Home'});
})
Renders the /views/index.jade
view with the {'title': 'Home'}
view model.
A request without a matching route, e.g:
GET /page
Will execute the /public/page.jade
template, passing these HTTP request vars as the viewModel:
Map viewModel = {
'method': req.method,
'uri': req.uri,
'headers': req.headers,
'request': req,
'response': req.response,
}
StaticFileHandler #
Serve static files for requests that don't match any defined routes:
app.use(new StaticFileHandler('public'));
Serves static files from the /public
folder.
Other APIs #
// Register different Formatters
abstract class Formatter implements Module {
String get contentType;
String get format => contentType.split("/").last;
String render(HttpContext ctx, dynamic viewModel, [String viewName]);
}
// The loglevel for express
int logLevel = LogLevel.Info;
// Inject your own logger, sensitive on logtypes (error, warning...)
typedef Logger(Object obj, {int logtype});
Logger logger = (Object obj, {int logtype}) => print(obj);
Contributors #
- mythz (Demis Bellot)
- financeCoding (Adam Singer)