crosstalk-ide
crosstalk-ide is a Crosstalk Swarm emulator enabling local Crosstalk Worker development and testing.
- Installation
- Usage
- Crosstalk worker environment
- Workers Gallery
- HOWTOs
- Worker Examples
- Development Examples
Installation
npm install crosstalk-ide
Usage
For starters, take a look at the examples folder and run the examples via:
node example.js
This simple initial example illustrates how to use the crosstalk-ide in order to run workers.
With example.js as a start, the next place to look would be at crosstalk.js which creates the Crosstalk sandbox that a worker runs in. That is the complete list of emulated worker functionality.
Finally, for now, addTestingArtifacts.js shows more of the testing functionality available in the development environment.
More examples are forthcoming.
Crosstalk worker environment
Crosstalk global object and available modules
Workers Gallery
HOWTOs
How to build a "Hello World" Crosstalk worker
Worker Examples
Simple 'hello world' worker
crosstalk.on( 'hello', function () {
crosstalk.emit( 'distributed world' );
});Alice and a sandwich (messages between workers)
Alice's worker #1
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', function () {
sandwichesReceived++;
});Alice's worker #2
setInterval( function () {
crosstalk.emit( 'sandwich' );
}, 5000 ); // every 5 secondsAlice and Bob
Alice's worker (Alice's account name is alice)
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', 'public', function () {
sandwichesReceived++;
});Bob's worker
setInterval( function () {
crosstalk.emit( '@alice.sandwich' );
}, 5000 ); // every 5 secondsAlice and Bob using request-reply
Alice's worker
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', 'public', function () {
sandwichesReceived++;
});
setInterval( function () {
crosstalk.emit( '@bob.make.me.a.sandwich' );
}, 5000 ); // every 5 secondsBob's worker
crosstalk.on( 'make.me.a.sandwich', 'public', function () {
crosstalk.emit( '@alice.sandwich' );
});Eve sandwich spam
Eve's worker
setInterval( function () {
crosstalk.emit( '@alice.sandwich' );
}, 1000 ); // every 1 secondAlice's improved worker
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', '@bob', function () {
sandwichesReceived++;
});
setInterval( function () {
crosstalk.emit( '@bob.make.me.a.sandwich' );
}, 5000 ); // every 5 secondsEve-n better (refactoring configuration)
Alice's configuration file
{ "authorized": "@bob" }Alice's refactored worker
var config = require( 'config' );
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', config.authorized, function () {
sandwichesReceived++;
});
setInterval( function () {
crosstalk.emit( '@bob.make.me.a.sandwich' );
}, 5000 ); // every 5 secondsGeneric Bob
Carl's worker
crosstalk.on( 'sandwich', '@bob', function () {
// got sandwich!
});
crosstalk.emit( '@bob.make.me.a.sandwich', { requester : '@carl' } );Generalized Bob's worker
crosstalk.on( 'make.me.a.sandwich', 'public', function ( params ) {
if ( params && params.requester ) {
crosstalk.emit( params.requester + '.sandwich' );
} else {
crosstalk.emit( '@alice.sandwich' );
}
}); // crosstalk.on 'make.me.a.sandwich'C-C-C-C-C-Callback!
Bob worker using callback
crosstalk.on( 'make.me.a.sandwich', 'public', function ( params, callback ) {
if ( callback ) {
// convention is callback( <error>, <response> )
callback( null, { sandwich : 'sandwich' } );
}
}); // crosstalk.on 'make.me.a.sandwichCarl's new worker
crosstalk.emit( '@bob.make.me.a.sandwich', {}, function ( error, response ) {
if ( ! error && response && response.sandwich == 'sandwich' ) {
// got sandwich!
}
}); // crosstalk.emit @bob.make.me.a.sandwichSecure Callback
Carl's more secure worker
crosstalk.emit( '@bob.make.me.a.sandwich', {}, '@bob', function ( error, response ) {
if ( ! error && response && response.sandwich == 'sandwich' ) {
// got sandwich!
}
}); // crosstalk.emit @bob.make.me.a.sandwichHow many sandwiches? (web worker)
Alice's generic web sandwich worker
var config = require( 'config' );
var sandwichesReceived = 0;
crosstalk.on( 'sandwich', config.authorized, function () {
sandwichesReceived++;
});
setInterval( function () {
crosstalk.emit( '@bob.make.me.a.sandwich' );
}, 5000 ); // every 5 seconds
// we create a callback that will be fired every time
// when someone navigates to http(s)://alice-sandwiches.worker.crxtalk.com
var myRequestListener = function ( req, res ) {
res.end( 'received ' + sandwichesReceived + ' sandwiches' );
};
// register our callback at our subdomain (alice-sandwiches)
crosstalk.emit( '~crosstalk.api.http.listen',
{
subdomain : 'alice-sandwiches',
requestListener : myRequestListener
},
'~crosstalk',
function ( error, response ) {
// error or response to register call ~crosstalk.api.http.listen
}
); // crosstalk.emit ~crosstalk.api.http.listenHow many secure sandwiches?
Alice's https we sandwich worker
/* same code as in above http worker */
// register our callback at our subdomain (alice-sandwiches)
crosstalk.emit( '~crosstalk.api.http.listen',
{
httpsOnly : true, // <- set 'httpsOnly' flag to true
subdomain : 'alice-sandwiches',
requestListener : myRequestListener
},
'~crosstalk',
function ( error, response ) {
// error or response to register call ~crosstalk.api.http.listen
}
); // crosstalk.emit ~crosstalk.api.http.listenPersistent sandwich (storing state)
Alice's persistent sandwich count worker
var config = require( 'config' );
var sandwichesReceived = 0;
// periodically backup our sandwich count
setInterval( function () {
crosstalk.emit( '~crosstalk.api.aws.s3.putObject',
{
accessKeyId : config.accessKeyId,
bucketName : config.bucketName,
object : { sandwichCount : sandwichesReceived },
objectName : 'sandwiches.json',
secretAccessKey : config.secretAccessKey
},
'~crosstalk',
function ( error, response ) {
// handle errors if any
}
); // crosstalk.emit ~crosstalk.api.aws.s3.putObject
}, 1000 * 60 * 60 ); // every hour
/* the rest of Alice worker is as before */Recoverable sandwich
Alice's worker that initializes from existing sandwich count
var config = require( 'config' );
var sandwichesReceived = 0;
// get saved sandwich count from an object in S3
crosstalk.emit( '~crosstalk.api.aws.s3.getObject',
{
accessKeyId : config.accessKeyId,
bucketName : config.bucketName,
objectName : 'sandwiches.json',
secretAccessKey : config.secretAccessKey
},
'~crosstalk',
function ( error, response ) {
if ( ! error ) {
sandwichesReceived += response.object.sandwichCount;
}
} // function ( error, response )
); // crosstalk.emit ~crosstalk.api.aws.s3.getObject
/* the rest of Alice's worker follows as before */Development Examples
Click on the links to see runnable worker project examples. All examples can be found here.
Make HTTP(S) requests from local worker in development
HTTP example
worker = ide.run( workerPath );
worker.dontMockHttp = true;HTTPS example
worker = ide.run( workerPath );
worker.dontMockHttps = true;Mock HTTP(S) responses
HTTP(S) response example
worker = ide.run( workerPath );
worker
.sendHttpResponseTo( "some.host.com", "/some/path" )
.writeHead( 200, { "Content-Type" : "text/html" } )
.write( "some response", "utf8" )
.addTrailers( { "My-Trailer": "trailer-value" } )
.end();Send messages to Crosstalk Swarm from local worker in development
proxy example
worker = ide.run( workerPath );
worker.crosstalkToken = "your-crosstalk-session-token"; // from when you login
worker.proxy = [ "~crosstalk.api.worker.version", "@my.production.worker" ]Mock worker environment
You can set the return value returned by require( 'env' ).version to mock what environment version the worker runs in. This only affects this value and does not change the actual crosstalk-ide behavior.
version example
worker = ide.run( workerPath );
worker.env.version = "0.7.2"; // set value of worker environmentThen within a worker you can get it via:
var env = require( 'env' );
env.version; // will be "0.7.2"