Create chainable sync/async APIs easily
npm install chaintastic
Create a chain with a set of chainable methods:
import Chaintastic from 'chaintastic';
const chain = Chaintastic({
sum(a, b) {
return a + b;
}
display(value) {
return 'Your number is ' + value;
}
});
Your chain is ready to go! You can wrap a initial value using the init method, and then chain methods. The return value of a method call is passed as the first argument of the next method call. You can end the chain using then.
chain.init(10).sum(5).display().then(console.log); // 'Your number is 15'
You might want to perform async operations in your chained methods. You can do it in two ways:
Every method call is also passed a callback function as the last argument. If your method returns undefined, Chaintastic will assume that you're going to use the callback at some point.
const chain = Chaintastic({
getValue(cb) {
setTimeout(() => cb('world'), 5000);
}
display(value) {
return 'Hello, ' + value + '!';
}
});
chain.getValue().display().then(console.log); // 'Hello, world!' after 5 seconds
Or, you can return a thenable value, like a Promise. If the return value is a thenable, then the next method call will follow it.
const chain = Chaintastic({
getHTML() {
return fetch('https://www.example.com').then(body => body.text());
}
display(value) {
return 'Source code:\n' + value;
}
});
chain.getHTML().display().then(console.log); // 'Source code: ...' after load finished
Primitives would be mapped to getter functions.
const chain = Chaintastic({
name: 'Nicolás',
greet(name) {
return 'Hello, ' + name + '.';
}
});
chain.name().greet().then(console.log); // 'Hello, Nicolás.'