Cangaroo helps developers integrating their apps with any service. It is a Rails Engine that can be installed on any Rails application and is used as a connection hub from one or multiple applications and external services.
[TODO] add self-explanatory image here.
Cangaroo allows to move the logic related to external services connection and synchronization between multiple applications.
This logic will reside in a shared area without the need to replicate it for any system component. It's especially useful when working with larger system formed by multiple applications that need to send messages to each other and to external services.
This kind of configuration allows:
- don't overload your application resources allowing to scale the number of requests that can be handled;
- in case of errors or downtimes of any system component, Cangaroo stores each message and retry sending it until it's successfully delivered;
- use and contribute to a lot of integrations that has already be done by the community.
Cangaroo integrations are pieces of code that allow interacting with external services via API.
An usual flow is:
- Cangaroo receives some data from an application;
- Data is sent to one or more integrations;
- Integrations convert data to be compatible with an external service API;
- Integrations send converted data to the external service.
Cangaroo is born with built-in Wombat extensions compatibility. All the old Wombat exensions have been migrated to the Cangaroo organization so that they can be maintained more easily.
Some time ago Spree decided to shut down Wombat and to release its closed source code to customers only, so we had to decide how to go ahead, and the alternative were:
- hosting Wombat by ourselves for some of our clients
- starting a new open source project with an API compliant with Wombat.
We believe in open source so we chose the latter.
The idea is a bit different from Wombat, the goal of this project is to provide a backwards compatible API and give the developers the freedom to change and customize it.
If you're interested in hosting an admin interface similar in functionality to
Wombat, check out the cangaroo_ui
gem.
We hope this project can help to make the migration from Wombat easier and we believe the Spree/Solidus community will help to make it better.
- rails (>= 4.2.4)
Cangaroo is a Rails Engine so as usual you can install it by using Bundler by adding it to your application's Gemfile:
# Gemfile
gem 'cangaroo'And then executing:
$ bundle
Install the needed migration with:
$ bin/rake cangaroo:install:migrations
And then executing:
$ bin/rake db:migrate
Now mount the engine into your routes.rb file:
# routes.rb
...
mount Cangaroo::Engine => "/cangaroo"
...First create a connection:
Cangaroo::Connection.create(
name: 'mystore',
url: 'http://www.mystore.com',
key: 'puniethahquoe5aisefoh9ci0Shuaniemei6jahx',
token: 'ahsh8phuezu3xuhohs6kai5vaB1tae0wiy1shohp'
)then create a cangaroo job:
module Cangaroo
class ShipmentJob < Cangaroo::Job
connection :mystore
path '/update_shipment'
def perform?
type == 'shipments' &&
payload['status'] == 'shipped'
end
end
endand add this job to the Rails.configuration.cangaroo.jobs:
# config/initializers/cangaroo.rb
Rails.configuration.cangaroo.jobs = [Cangaroo::ShipmentJob]Cangaroo provides a Push API where you can send your data. After data has been received, Cangaroo sends data to integrations and webhooks based on your business logic.
This is the detailed flow:
- Cangaroo receives the data
- If some error like "wrong key and token" or "malformed json" is raised
Cangaroo returns an HTTP status code based on the error type:
406for wrong request401for Unauthorized500for wrong json schema500for Cangaroo internal errors
- If there are no errors, for each object in the json body, Cangaroo checks
what jobs must be enqueued by calling the
#perform?method. Each job returningtrueto#perform?will be enqueued.
Cangaroo has just a single endpoint where you can push your data, based on
where Cangaroo::Engine is mounted, it will be reachable under the /endpoint
path. For example, if the Cangaroo::Engine is mounted under /cangaroo the
Push API path will be /cangaroo/endpoint.
When you push to the endpoint the HTTP Request must respect this conventions:
- It must be a
POSTrequest - It must be an
application/jsonrequest so you have to set theContent-Typeheader toapplication/json - The request must have the
X-Hub-StoreandX-Hub-Access-Tokenheaders set to a value that exists in theCangaroo::Connectionmodel (to learn more refer to theConnectiondocumentation below) - The request body must be a well formatted json.
The json body contains data that will be processed by Cangaroo, the following is an example of an order that will be processed on Cangaroo:
{
"orders": [
{
"id": "O154085346",
"status": "complete",
"email": "[email protected]"
}
]
}The root objects of the json body must contain an array with the objects that
Cangaroo needs to process. The only required field for the objects contained
in the arrays will be the id key.
Push API also supports multiple objects so a request with the following body:
{
"orders":[
{
"id":"O154085346172",
"state":"cart"
},
{
"id":"O154085343224",
"state":"payed"
}
],
"shipments":[
{
"id":"S53454325",
"state":"shipped"
},
{
"id":"S53565543",
"state":"waiting"
}
]
}
will create 2 orders and 2 shipments.
When Cangaroo receives the request it responds with a 200(OK) HTTP status code and the response body will contain numbers of the objects in the payload, for example for the previous request the response will be:
{
"orders": 2,
"shipments": 2
}if something goes wrong Cangaroo responds with an HTTP error code with an error message in the body, for example:
{
"error": "The property '#/orders/0' did not contain a required property of 'id' in schema"
}Connection are services that can send and receive data from Cangaroo. Each connection must have these fields:
- name - (required, String) A generic name for this connection
- url - (required, String) The url where Cangaroo pushes the data
- key - (required, String) It's used for authentication (used to check the request's 'X-Hub-Store' header)
- token - (required, String) It's used for authentication (used to check the request's 'X-Hub-Access-Token' header)
- basic_auth - (optional, Boolean) Defaults to false. If you would like to
use HTTP basic auth in your integration instead of Wombat's key + token.
Basic auth is handled Stripe-style,
without a username using
keyas your password. - parameters - (optional, Hash) Used as parameters when Cangaroo makes a request to this connection
For now we don't have a Web GUI so you have to create the connection on your own by running the code somewhere on your server, for example from the Rails console:
Cangaroo::Connection.create(
name: 'mystore',
url: 'http://www.mystore.com',
key: 'puniethahquoe5aisefoh9ci0Shuaniemei6jahx',
token: 'ahsh8phuezu3xuhohs6kai5vaB1tae0wiy1shohp',
parameters: {
'channel': 'mysubstore'
}
)Jobs are where the payload is pushed to the configured connection.
To allow a job to be executed add it to the Rails.configuration.cangaroo.jobs
configuration, for example in an initializer:
# config/initializers/cangaroo.rb
Rails.configuration.cangaroo.jobs = [Cangaroo::AddOrderJob, Cangaroo::UpdateShipmentJob]The Cangaroo::Job class inherits from ActiveJob::Base, so you can use
any 3rd-party queuing library supported by ActiveJob.
When the job is performed Cangaroo makes a POST request to the connection with
the configured path and build the json body with the result of the #transform
instance method merged with this attributes:
request_id- is thejob_idcoming fromActiveJob::Baseparameters- are the parameters configured by theparametersclass method
You can use the following Cangaroo::Job class methods to configure the job's
behaivor:
- connection - is the connection name (see connection for more info)
- path - this path will be appended to your
connection.url - parameters - these parameters will be merged with
connection.parameters, they will be added to the json body.
it also has a #perform? instance method that must be implemented. This method
must return true or false as Cangaroo will use it to understand if the job
must be performed. Inside the #perform? method you'll be able to access the
source_connection, type and payload instance attributes.
The #transform instance method can be overridden to customize the json body
request, it will have the source_connection, type and payload variables
(like the #perform? method) and must return an Hash.
The following is an example of a Cangaroo::Job:
module Cangaroo
class ShipmentJob < Cangaroo::Job
connection :mystore
path '/update_shipment'
parameters({ timestamp: Time.now })
def transform
payload = super
payload['shipment']['updated_at'] = Time.now
payload
end
def perform?
type == 'shipments' &&
payload['status'] == 'shipped'
end
end
endSuppose that the mystore connection has a url set to "http://mystore.com"
an the payload is something like:
{ "id": "S123", "status": "shipped" }It will do a POST request to http://mystore.com/update_shipment with
this json body:
{
"request_id": "088e29b0ab0079560dea5d3e5aeb2f7868af661e",
"parameters": {
"timestamp": "2015-11-04 14:14:30 +0100"
},
"shipment": {
"id": "S123",
"status": "shipped"
}
}Tests are written using rspec and Appraisals
- Run
bundle exec appraisal installbefore running any specs bundle exec rakewill run the test suite for rails 4 and rails 5bundle exec rspecwill run specs for the latest rails version- if you want run specs only for for rails 4 run
appraisal rails-4 rake, for rails 5 runappraisal rails-5 rake.
Cangaroo is copyright © 2016 Nebulab. It is free software, and may be redistributed under the terms specified in the license.
Cangaroo is funded and maintained by the Nebulab team.
We firmly believe in the power of open-source. Contact us if you like our work and you need help with your project design or development.