living high on simple DI
Heavily inspired by Angular ui.router $resolve.
I wrote this after a stressful day of Shepherd.js and other DI libs making me feel stupid. I am making some micro-services and didn't want to deal with proper DI, I just wanted something like a recursive Promise.all()
Ripped some regex magic out of Angular's $inject code, combined with a rewrite of ui.router's $resolve, and you get some sexy Promise dependency injection thing that looks like it was made with sweet.js.
var resolve = require("morphine");
resolve({
now: function(path){
return path;
},
future: function(path, now){
return path + now;
}
},{path: "something"})
.then(console.log);
output
{ path: 'something',
now: 'something',
future: 'somethingsomething' }
resolve(invokables, [knowns]) -> promise
invokeables:
An invokeable is a name (key) and a function with zero or more arguments that map to some or all of the keys in the invokeables
object (resursive), or the knowns
object. The return values for the invokeables
functions can be promises. internally they get converted to promises anyway.
knowns:
an object of primative values (strings, ints).
resolve():
The return value (promise) that resolve
gives is an object with the keys from both the invokeables
and knowns
list, and the resolved values from all of the invokeables
(primatives).
resolve({
now: function(path){
return "something";
}
})
.then(console.log);
output
{ path: 'something'}
var fs = require("q-io/fs");
resolve({
config: function(configPath){
return fs.read(configPath).then(JSON.parse);
}
},{configPath: "config.json"})
.then(console.log);
output
{ configPath: 'config.json',
config: { obj: { field: [Object] }, server: { port: 1111 } } }
what happens when you you make typos
resolve({
path: function(){
return "something";
},
fail: function(noResolution, path){
return noResolution + path;
}
})
.then(null, _.partial(console.log, "failure case"));
output
failure case [Error: can not resolve all dependencies: noResolution]