README
Antiquefy
Create callback-last style functions from functions returning promises and from generator functions.
Installation
Install from NPM:
npm install antiquefy
Require Antiquefy in your code:
var antiquefy = require('antiquefy');
Examples
In most cases asynchronous functions which return their results in a callback function can be easily promisified using various promise libraries. However, if you have a 3rd party function which takes a hook-like function with a done
callback, the process is not so straightforward.
For example, passport-local strategy takes a verify
callback function which is itself supplied with a done
callback. Antiquefy handles the calling of the done
callback automatically after the antiquefied function has been finished. The done
callback is expected to be an error first style callback.
Generators
Here is the antiquefied version of the Passport local strategy example using generators:
passport.use(new LocalStrategy(antiquefy(
function*(username, password) {
var user = yield User.findOne({ username: username });
if (!user) {
return false;
}
if (!user.verifyPassword(password)) {
return false;
}
return user;
}
)));
Promises
The above could also be achieved using promises:
passport.use(new LocalStrategy(antiquefy(
function(username, password) {
return User.findOne({ username: username }).then(function(user) {
if (!user) {
return false;
}
if (!user.verifyPassword(password)) {
return false;
}
return user;
});
}
)));
Functionally this is equivalent to the generator example, but is little more verbose and requires one extra indentation level.
API
⇒ antiquefy(fn, [options])Function
Convert the given function or generator function into a function which takes a done
callback.
Param | Type | Description |
---|---|---|
fn |
Function or GeneratorFunction |
The function (or generator function) to Antiquefy. |
options |
Object |
Options for Antiquefy. |
options.spread |
boolean |
Set this to true if you wish to spread the returned array elements as individual arguments for the done callback.Optional Default: false |
Spreading arguments
If the done
callback takes more than one parameter, it can be supplied multiple arguments by returning an array and setting the spread
option to true
.
var sum = antiquefy(function(a, b) {
return [a, b, a + b];
}, { spread: true });
sum(4, 6, function(error, first, second, sum) {
console.log(first); // 4
console.log(second); // 6
console.log(sum); // 10
});
This works similarly to Bluebird's asCallback(..)
and that is what Antiquefy uses internally.
Tests
Unit tests can be run by executing:
npm test