what-is-HAPIness
Daniela Borges
Daniela Borges
hapijs/bossy lead maintainer, mentor
photography amateur
origami master
full-stack dev
ylder
@sericaia
Walmart
what-is-hapi
Which problems hapi tried to solve?
...there are already solutions in the market
what-is-hapi
A rich framework for building applications and services
HTTP API server
what-is-hapi //main goals
everything is a PLUGIN in hapi
focus on writing reusable
application logic
what-is-hapi //main goals
1. configuration is better than code
2. business logic must be isolated from transport layer
>>> delivering business value
what-is-hapi //main goals
1. configuration is better than code
var Hapi = require('hapi');
var config = {
dbConnection: 'mongodb://myvoodoapp',
drinks: ['capirinha', 'mojito', 'margarita']
};
var server = new Hapi.Server({
app: config
});
server.start();what-is-hapi //main goals
1. configuration is better than code
var Hapi = require('hapi');
var config = {
dbConnection: 'mongodb://myvoodoapp',
drinks: ['capirinha', 'mojito', 'margarita']
};
var server = new Hapi.Server({
app: config
});
server.start();accessible through
server.settings.app
what-is-hapi //main goals
2. business logic must be isolated from transport layer
var Hapi = require('hapi');
var server = new Hapi.Server();
server.connection({
host: 'localhost',
port: 8000
});
server.route({
method: 'GET',
path:'/api/mediterraneajs',
handler: function (request, reply) {
reply('Mediterranea JS...the best route to meet Barcelona!');
}
});
server.start();index.js
what-is-hapi //main goals
2. business logic must be isolated from transport layer
what-is-hapi //main goals
even better
...using PLUGINS!
what-is-hapi //main goals
even better...using plugins!
var register = function (plugin, options, next) {
plugin.route({
method: 'GET',
path:'/api/mediterraneajs',
handler: function (request, reply) {
reply('Mediterranea JS...the best route to meet Barcelona!');
}
});
next();
};
register.attributes = {
name : 'mediterraneaApi',
version : '1.0.0' // I am confident!
}
module.exports = register;mediterraneaApi.js
what-is-hapi //main goals
even better...using plugins!
var Hapi = require('hapi');
var server = new Hapi.Server();
server.connection(...);
// Register the API
server.register( [ mediterraneaApi, (...) ] ,
function (err) {});
server.start();
index.js
what-is-hapi //main goals
small things matter.. use prefix, please! I am a lazy dev
source: http://projectzomboid.com/blog/wp-content/uploads/2014/08/BC_Keep_Calm_and_Stay_Lazy_2_copy-712x462.jpg
what-is-hapi //main goals
small things matter.. c'mon, use prefix!
var mediterraneaApi = require('./mediterraneaApi.js');
server.register({register: mediterraneaApi}, {
routes: {
prefix: '/api'
}
}, function (err) {
});
what-is-hapi //request lifecycle
{ proposal: understand request object and request lifecycle }
what-is-hapi //request lifecycle
{ Request object }
The request object is created internally for each incoming request.
The request object methods and properties change throughout the request lifecycle.
// hapi docs
what-is-hapi //request lifecycle
Why I may need this?
- route interception
- validation
- authentication
- encryption (ex. create SHA1 hash of each request body)
- ...
what-is-hapi //request lifecycle
Extension Points
what-is-hapi //demo
we can modify each extension point using
#1 FACT
server.ext(extension_point_event, method, [options])
what-is-hapi //request lifecycle
'onRequest' extension point
server.ext('onRequest', function (request, reply) {
request.setUrl('/vodoo');
return reply.continue();
});what-is-hapi //request lifecycle
'onRequest' extension point
server.ext('onRequest', function (request, reply) {
request.setUrl('/vodoo');
return reply.continue();
});
server.route({
method: 'GET',
path: '/vodoo',
handler: function (request, reply) {
return reply("making vodoo interceptor @MediterraneaJS");
}
});
server.start();what-is-hapi //request lifecycle
Extension Points
what-is-hapi //request lifecycle
what-is-hapi //request lifecycle
Let's divide to conquer...
what-is-hapi //request lifecycle
'onRequest'
what-is-hapi //request lifecycle
Authentication
what-is-hapi //request lifecycle
verify route permissions
- may be specified by a strategy
set and authenticate payload
what-is-hapi //request lifecycle
server.auth.strategy(name, scheme)
identify our specific strategy
general type of auth
what-is-hapi //request lifecycle
var HapiAuthBasic = require('hapi-auth-basic');
//...
var validate = function (username, password, callback) {
//...
};
server.register(HapiAuthBasic, function (err) {
server.auth.strategy('simple', 'basic', { validateFunc: validate });
server.route({
method: 'GET',
path: '/',
config: {
auth: 'simple',
handler: function (request, reply) {
reply('hello, ' + request.auth.credentials.user);
}
}
});
});uses hapi-auth-basic
defines 'basic' scheme
what-is-hapi //request lifecycle
var HapiAuthBasic = require('hapi-auth-basic');
//...
var validate = function (username, password, callback) {
//...
};
server.register(HapiAuthBasic, function (err) {
server.auth.strategy('simple', 'basic', { validateFunc: validate });
server.route({
method: 'GET',
path: '/',
config: {
auth: 'simple',
handler: function (request, reply) {
reply('Welcome, ' + request.auth.credentials.user);
}
}
});
});defines the strategy
what-is-hapi //request lifecycle
var HapiAuthBasic = require('hapi-auth-basic');
//...
var validate = function (username, password, callback) {
//...
};
server.register(HapiAuthBasic, function (err) {
server.auth.strategy('simple', 'basic', { validateFunc: validate });
server.route({
method: 'GET',
path: '/',
config: {
auth: 'simple',
handler: function (request, reply) {
reply('hello, ' + request.auth.credentials.user);
}
}
});
});sets auth = our strategy
what-is-hapi //request lifecycle
server.auth.scheme('basic', scheme);
server.auth.strategy('vodoo', 'basic');
server.auth.default('vodoo');
what-is-hapi //request lifecycle
More about authentication
hapi-auth-cookie
uses 'cookie' schema
bell
3rd party
uses 'bell' schema
server.auth.strategy('twitter', 'bell', {
provider: 'twitter',
password: 'encryption_password',
clientId: 'client_id',
clientSecret: 'client_secret'
});what-is-hapi //request lifecycle
Validation
what-is-hapi //request lifecycle
plugin.route({
method: 'GET',
path:'/welcome/{name}',
handler: function (request, reply) {
var welcomeMsg = 'Welcome ' + request.params.name + "!\n";
welcomeMsg += 'Are you ' + request.query.mood + "?";
reply(welcomeMsg);
},
config: {
validate: {
params: {
name: Joi.string().required()
},
// ...
}
}
});Validate params
what-is-hapi //request lifecycle
plugin.route({
method: 'GET',
path:'/welcome/{name}',
handler: function (request, reply) {
var welcomeMsg = 'Welcome ' + request.params.name + "!\n";
welcomeMsg += 'Are you ' + request.query.mood + "?";
reply(welcomeMsg);
},
config: {
validate: {
// ...
query: {
mood: Joi.string().valid(["happy","sad"])
.default("happy")
}
}
}
});Validate query
what-is-hapi //request lifecycle
May contain an object or array of objects with actions
Actions 'terminate' with a reply(), and pass the result to the next step
Route prerequesites
what-is-hapi //request lifecycle
var caipirinhaIngredients = function (request, reply) {
return reply('Cachaça, lime, and sugar');
};
var mojitoIngredients = function (request, reply) {
return reply('Mint leaves, limes, rum, sugar, and soda');
};
var partyDrinks = function (request, reply) {
return reply(request.pre.caipirinha + ' and ' + request.pre.mojito);
};
Route prerequesites
what-is-hapi //request lifecycle
server.route({
method: 'GET',
path: '/party',
config: {
pre: [
[
/* capirinha and mojito executed in parallel */
{ method: caipirinhaIngredients, assign: 'caipirinha' },
{ method: mojitoIngredients, assign: 'mojito' }
],
{ method: partyDrinks, assign: 'drinks' },
],
handler: function (request, reply) {
return reply(request.pre.drinks);
}
}
});Route prerequesites
what-is-hapi //request lifecycle
between onPreHandler and onPostHandler we can change reply(), i.e we can change the response
#2 FACT
what-is-hapi //request lifecycle
uses the signature function(request, reply)
Route handler
request object
reply interface
what-is-hapi //request lifecycle
The response object contained in request.response may be modified
'onPostHandler'
what-is-hapi //request lifecycle
always called
The response object contained in request.response may be modified
'onPreResponse'
what-is-hapi //request lifecycle
may emit 'request-error' event
finally returns data to client!
Send response
what-is-hapi //request lifecycle
request.tail([name])
Returns a tail function which must be called when the tail activity is completed
server emits one 'tail' event when all tails are completed
tails
what-is-hapi //request lifecycle
Extension Points/Conclusion
hapi-auth-basic/cookie/bell
joi
*
*
* always called
what-is-hapi //latest news
What's next in hapi?
what-is-hapi //latest news
micro-services plugin
Chairo
Hapi Mentorship program
Call for lead maintainers
what-is-hapi //latest news
Q & A
Daniela Borges
hapijs/bossy lead maintainer, mentor
photography amateur
origami master
full-stack dev
ylder
@sericaia