API-first content management fundamentally reverses the traditional CMS development approach, something we’ve covered in previous chapters on the emergence of Headless CMS. Instead of designing the CMS and then adding APIs as an afterthought, the API-first strategy starts with creating robust and flexible APIs to manage content and assets. These APIs become the foundation upon which the rest of the CMS is built.
The rise of API-first CMS was a response to the growing need for omnichannel content delivery. When content needs to be seamlessly distributed across websites, mobile apps, IoT devices, and more, traditional CMSs fall short. They are often rigid and not well-suited for the fluidity and scalability required for modern ecosystems. API-first CMS, with its decoupled architecture, addresses these challenges, offering unparalleled flexibility and scalability.
Probably worth clarifying here that API-first CMS and Headless CMS are basically the same thing - but blame our marketing guy for wanting to create a whole new section for this just for SEO.
Before starting to look at the common API types and get into technical specifics, let’s establish some foundational best practices for getting the most out of adopting the Headless CMS approach when it comes to API design.
This is relevant for designing content APIs, but if you’re selecting a Headless CMS, then you should make sure that your vendor is following these guidelines as part of your evaluation.
Ensure that the APIs are scalable and can handle the expected load as your content and audience grow. This isn’t only applicable to the sheer volume of data the APIs can deliver in terms of content and assets, but also the query complexity that can be handled based on your projects’ schema and structure.
Implement robust authentication and authorization protocols to secure access to your APIs. While the APIs themselves should always encrypt data in rest and transit, they should also allow for varied access control through user authentication, roles, and PAT (auth tokens) permissions.
Create APIs that are flexible enough to accommodate future changes in content structure and front-end technologies.
Maintain comprehensive and up-to-date API documentation to ensure ease of use for developers. Docs are a core feature to the adoption of APIs by providing a better DX, and this should always be a consideration when designing APIs, not an afterthought.
Optimize APIs for performance, ensuring fast content delivery. No one likes to wait for an extra 100ms, so ensuring that responses are cached, delivered quick, and well optimized go a long way in designing performant APIs.
Now that we’ve got the basics in place, let’s dive into the most common API types you’d find in the CMS world.
REST (Representational State Transfer) is an architectural style that conforms to a set of constraints when developing web services. It was introduced as a successor to SOAP APIs. REST, or RESTful APIs, are Web Service APIs that follow the REST standards. SOAP were restricted to delivering data in XML formats, and as the need for better structured data responses became prevalent in modern development, REST came about as a successor that primarily provided JSON. While REST can still support providing data in XML, HTML, or YAML, the most common format remains JSON.
When a client calls REST APIs the server transfers the resources in a standardized representation. They work by returning information about the source that was requested - and is translated into an easier to consume format - those JSON curly bois.
REST APIs also allow for modifications and additions from the client-side to the server.
A REST request is made up of the endpoint, HTTP method, Header, and Body.
An endpoint contains a URI (Uniform Resource Identifier) that helps in identifying the resource online.
REST APIs work on using HTTP verbs to perform CRUD operations:
POST: to Create
GET: to Read
PUT: to Update (replace)
PATCH: to Update (modify), and
DELETE: to Delete.
Headers provide information to clients and servers for purposes like caching, AB Testing, authentication, and more.
The body contains information that a client wants to send to a server, such as the payload of the request.
Quite simply put, GraphQL is a query language for APIs and a runtime for fulfilling those queries with existing data. GraphQL offers a comprehensive and clear outline of the data within your API. It empowers clients to precisely request what they require, without excess, simplifies the evolution of APIs over time, and supports the development of potent tools for developers.
The appeal of GraphQL largely comes from its core principle: requesting precisely what you need and receiving exactly that – no more, no less. This approach allows for highly predictable responses from your API queries, eliminating issues of overfetching or underfetching.
GraphQL APIs are organized in terms of types and fields, not endpoints, making them extremely easy to get up and running, since you can access all of your data from a single endpoint. GraphQL uses types to ensure apps only ask for what’s possible and provide clear and helpful errors. Apps can use types to avoid writing manual parsing code.
The folks over at Honeypot made a great documentary on GraphQL if you're keen to dive in!
REST and GraphQL aren’t the end of the content API spectrum, but they’re definitely the most commonly used. At times you may encounter other API types and extensions as well, and while we at DatoCMS don’t provide APIs in these specs, it’s probably worth knowing a little about them and why they exist.
SOAP is a protocol for exchanging structured information in web services. In content management, SOAP can be used for inter-application communication, enabling different systems to interact and exchange content data seamlessly. It is known for its high security and extensive standards, making it suitable for enterprise-level applications where robustness and formal contracts are required.
gRPC, a modern open-source framework, uses HTTP/2 to provide highly efficient and scalable communication between services. In content management, gRPC can facilitate rapid content synchronization across various microservices, thanks to its low-latency and language-agnostic nature. It's particularly useful for real-time content updates and complex transactional systems.
OData is a standard protocol for creating and consuming RESTful APIs. It's used in content management to standardize the querying and manipulation of data, allowing for more flexible data access from various client platforms. OData supports complex querying capabilities, making it easier to handle sophisticated content retrieval requirements.
JSON-RPC is a lightweight protocol that allows for remote procedure calls using JSON as its format. In the context of content management, it enables simple and efficient API calls for CRUD operations on content, with minimal overhead. It's favored in scenarios where speed and simplicity are more critical than comprehensive features.
XML-RPC is a protocol that uses XML to encode remote procedure calls. In content management systems, XML-RPC can be used for system interoperability, allowing different CMS platforms to communicate and exchange data. Its simplicity and wide adoption make it a viable option for basic content management tasks, especially in legacy systems.