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[express]
$ express
- do '# npm install -g express' beforehand, express command
generates nice template dir structure to get started
- last param in functions usually implies a callback
- app.param
map/assosiate some logic to a 'route parameter(s)', so when you enter such route
you can expect to have a variable filled for you, e.g. route: /sys/:id, let's say
id is 'listdb', then a db would get preloaded by the time we stepped into the route logic
- doing next(new Error('foo')) will stall and end middleware chain
[node]
- process.nextTick()
when you defined a function that return something, and takes in a callback,
make sure you callback on the next event loop-around, so at that point you
would return valid object, that callback might likely want to access/modify
use this to be nice, similar to yield()? delay executation of callback until next loop-around
[code analysis]
# npm install -g jslint
$ jslint --sloppy --white <file.js>
[make a copy of an array]
var foo = [1, 2, 3];
var bar = foo.slice(0);
- an object that listen for event must be subclass of
of events.EventEmitter, e.g. http.createServer()
I'm an eventer, I will emit events, and have a list of
who responds/listens to those, so we will see statements
such eventer.on('foo', somehandler)
[modules]
- now.js and dnode--socket.io namespace (function/var sharing)
[mongodb]
$ mongo; show dbs; use nodejs1; show collections; db.getCollectionNames(), db.users.find(), db.users.remove(), db.users.drop()
[debug node]
$ node --debug-brk app.js
$ node-inspector &
http://0.0.0.0:8080/debug?port=5858
- __proto__ in node-inspector imples functions/methods of the 'this' object
[module.exports vs exports]
- if you want your module to be of a specific object type (boolean, string, etc),
use module.exports; if you want your module to be a typical module instance, use exports
- result of attaching properties to module.exports is akin (same) to attaching properties to exports
- http://www.hacksparrow.com/node-js-exports-vs-module-exports.html
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