This lesson covers what an API is and why you might want to build one. Joe also explains the basic concepts behind any API and provides real world examples of existing APIs that you're probably familiar with as well as use cases for when and why you might want to build your own.
In this lesson Joe shows you where to locate the services module and it's documentation. Then walks through installing the services module and confirming that it's working. Followed by a quick overview of the module's codebase and a general overview of what the services module provides.
Additional resources
The API that we're going to be building through this series is a REST based API so we need to understand the basic tenants of RESTful web services. In this lesson Joe gives a short presentation explaining the basic terminology, workflow, and tennants of REST based web services.
Additional resources
This lesson walks through defining the URL that will serve as the endpoint for your API as well as all the basic configuration for your new services endpoint with the exception of resource configuration which is covered in the following lesson.
Additional resources
The services module exposes most of Drupal core's data as resources and provides CRUD operations and additional actions for each. In this lesson Joe will look at the available resources, talk about the various CRUD operations and actions and then enable the node resource and demonstrate retrieving node data as JSON from the services endpoint.
Additional resources
JSON Formatter - Chrome plugin to display results of a JSON request in a nicer way.
While cURL may not be the simplest way to interact with a REST API it is the most ubiquitous and the one that is most often referenced in documentation through the web. So to ensure that students have at least a baseline of understanding, and will know how to read the documentation in the future, in this lesson Joe takes a quick look at how to test our API with cURL by retrieving, and creating data.
Example Commands:
`curl http://localhost/demos/services-7x/docroot/api/v1/node/1`
`curl --data '{"title":"hello world!","type":"page"}' --header "Content-Type:application/json" http://localhost/demos/services-7x/docroot/api/v1/node`
Additional resources
Instead of using the CLI to test our API we can use the powerful Chrome REST Console plugin instead. This provides a nice GUI and makes it a little easier to both test and understand what is going on. In this lesson Joe looks at installing the plugin and making basic requests to our API using the REST Console interface.
Additional resources
The Chrome plugin demonstrated in this video is no longer available but there are many alternatives available. Use Postman or search for "REST client" to find tooling options.
In this lesson Joe will demontrate using additional parameters and arguments to refine the returned data when making requests from our API. As well as walking through the code that shows where the various parameters are defined and how you can find what options are available. Finally, we install the services tools module which provides some additional documentation.
Additional resources
Services implements resources for all of core's basic data types but sometimes the information returned in the response is either to much or to little and we want to make changes to the response data. In this lesson Joe will look at how we can write a simple custom module that implments basic hooks provided by the services module to allow us to alter the response returned by a request to the node resource.
Most of the actions we want to perform and data we want to retrieve from an API is likely restricted to authenticated users. This lesson will outline the process of making an authenticated request and walk the user through the configuration that is required for our services endpoint in order to start allowing session based authentication.
In this lesson Joe walks through making authenticated requests to our API with cURL. Although cURL can be a bit verbose when making authenticated requests it serves as a good way to talk about all the headers that are a required and a lowest common denominator for how you could accomplish authentication in just about any language or application.
Example commands
curl http://services-demo.lan/api/v1/user/login -d '{"name":"admin","pass":"admin"}' -H "Content-type: application/json" -H "Accept: application/json"
curl http://services-demo.lan/api/v1/system/connect -X POST
curl http://services-demo.lan/api/v1/system/connect -H "Cookie: SESS60f8c5b86739b7e326223b4ef35867b2=A86XHGJWlnDcMOGcArbOT-qHrsIi5P2NrcoNTXwWluw" -H "X-CSRF-Token: T77haXwD7JKOJsBlKP3p3kLbjQO96bQWvGJAE1_PUZM" -X POST
curl http://services-demo.lan/api/v1/user/login -X POST -H "Content-type: application/json" -H "Accept: application/json"
In this lesson Joe walks through making authenticated requests using the Chrome REST Console Plugin
Additional resources
The Chrome plugin demonstrated in this video is no longer available but there are many alternatives available. Use Postman or search for "REST client" to find tooling options.
All the power of views made available to your API. Really, what else is there to say? In this lesson Joe walks through installation and basic configuration of the services views module which provides the ability to expose views as resources via the services module.
Additional resources
In addition to using views to expose lists of things via our API we can also take advantage of views exposed filters to allow API consumers more control over the data they are receiving in a request. In this lesson Joe looks at accessing views exposed filters via REST requests by adding an exposed filter to both of the perviously created views and then walking through how the configuration of the view changes the behavior of the filter when used via the services API.
In addition to the built in support for core's data and actions the services module also provides a robust framework for exposing the data and actions of our custom modules as an API. In this lesson Joe writes a basic module which creates a custom resource for saving and retrieving a "checked in" status for an authenticated user.
Example commands:
Check a user's status
curl http://localhost/demos/services-7x-test/docroot/api/v1/drupalsquare/1 -H "Accept: application/json"
Check-in a user
curl http://localhost/demos/services-7x-test/docroot/api/v1/drupalsquare/checkin -X POST -H "Content-type: application/json" -H "Accept: application/json" -d '{"uid":1}'
Additional resources
An API that exposes data and actions to a 3rd party is only as good as the documentation for that API. Without good documentation no one will be able to make use of the API you just spent so much energy creating. In this lesson Joe shows some of his favorite API documentation examples and then walks through creating some basic documentation for the resource we created in the previous lesson.
Additional resources
Example - GitHub API Documentation
Example - Recurly Documentation
http://apiary.io - tool to assit in writing good documentation
The Migrate module itself contains some excellent examples of data migrations implementing the various APIs provided by the module and serves as the canonical documentation for how to write a migration. In this lesson we'll take a look at the beer and wine import examples provided with the migrate module as a way to familiarize ourselves with the concepts discussed earlier and to be able to see the code that makes up a basic migration before attempting to write our own. In practice these examples serve as a great starting point and can often times be copy/pasted and adjusted for your own needs.
Additional resources
Before we can write our own custom migration we need to construct the site that we're going to import data into and of course we need some source data to import. In this lesson we'll obtain some source data to work with and configure our Drupal site by installing a couple contributed modules, and creating the content types and fields necessary for our information architecture. During this process we'll also be taking a look at the baseball player and team data that we'll be importing and familiarizing ourselves a bit more with the tables and columns in our source database.
Note: The Lahman database structure has changed since this video was recorded, and the latest files provided by Lahman don't match what is used in the video. When following along with these examples you'll either need to use the 2012 source data, or make a few adjustments to field/table names throughout the source code as you follow along so that they match the current structure of the Lahman data.
Additional resources
Running your own migration requires a bit of setup and boilerplate code, Drupal needs to know where to find the source data, and the Migrate module needs to be provided with some basic information about our custom code. In this lesson we'll look at setting up Drupal to be able to connect to multiple databases, and then create the skeleton of a simple module which will house our custom migration code and an implementation of hook_migrate_api(). Finally we'll create a base class from which we can begin writing our own custom migrations, and talk about why this is a good way to start organizing our migration.
In this lesson we're going to write our first custom data migration and start importing some of the player data in to Drupal. The primary concepts covered in this lesson are the creation of a migration class following the pattern necessary for Migrate module to be able to discover our code and then dealing with defining source and destination objects so that the Migrate module will know where to read data from and where to write data to. Finally we'll add a simple single field mapping where we map the player's name to the node.title field allowing us to run the migration for the first time and import some real data.