GraphQL Advantages and Disadvantages

When Facebook build GraphQL, they needed a powerful data-fetching API which can handle all the task of Facebook, yet simple and easy to learn and use by their product developers. GraphQL was developed to rebuild Facebook's native mobile applications.

GraphQL is a query language. It provides a query in the form of a string that is sent to a server. The server interprets the query and then returns the result in the form of JSON format to the client.

Advantages of GraphQL

Following is a list of major advantages of GraphQL:

1. GraphQL is faster

GraphQL is way faster than other communication APIs because it facilitates you to cut down your request query by choosing only the specific fields you want to query.

2. Best for complex systems and microservices

We can integrate multiple systems behind GraphQL's API. It unifies them and hides their complexity. The GraphQL server is also used to fetch data from the existing systems and package it up in the GraphQL response format. This is most beneficial for legacy infrastructures or third-party APIs that are enormous in size and difficult to maintain and handle.

When we have to migrate from a monolithic backend application to a microservice architecture, the GraphQL API can help us to handle communication between multiple microservices by merging them into one GraphQL schema.

3. No over-fetching and under-fetching problems

The main advantage of GraphQl over REST is that REST responses contain too much data or sometimes not enough data, which creates the need for another request. GraphQL solves this problem by fetching only the exact and specific data in a single request.

4. Hierarchical Structure

GraphQL follows a hierarchical structure where relationships between objects are defined in a graphical structure. Here, every object type represents a component, and every relationship field from an object type to another object type represents a component wrapping another component.

5. Defines a data shape

When we request GraphQL queries to the server, the server returns the response in a simple, secure, and predictable shape. So, it facilitates you to write a specific query according to your requirement. This makes GraphQL really easy to learn and use.

6. Code-sharing

We can share the GraphQL fields used in multiple queries at a higher component level for reuse. This feature is referred to as fragments and allows you to get different data while keeping the same schema field.

7. Strongly typed

GraphQL is a strongly typed language where each level of a GraphQL query corresponds to a particular type, and each type describes a set of available fields. So, it is similar to SQL and provides descriptive error messages before executing a query.

8. Protocol, not a storage

Arbitrary functions back GraphQL fields on the servers. They do not dictate or provide any backing storage. Instead, GraphQL takes advantage of your existing code.

9. Introspective

We can query a GraphQL server for its supporting types. It creates a powerful platform for tools and client software such as application framework, Relay, or IDEs like GraphiQL. GraphiQL facilitates developers to learn and explore an API quickly.

10. Latest version not required

In GraphQL, the result set or returned data is very specific according to the client's query, so; it is very simple and easy for the server to generalize it. When we add new product features, additional fields to the server, they don't affect the existing clients. You can use the older server without any worry because server fields can be deprecated but continue to function. This compatible process doesn't require the need for an incrementing version number. You can see that Facebook is using the same version of GraphQL API in their applications.

Disadvantages of GraphQL

Although GraphQL has negligible disadvantages over its advantages, we are giving some disadvantages here. Following is the list of disadvantages of GraphQL:

1. GraphQL Query Complexity

Don't mistake GraphQL as a replacement for server-side databases. It is just a simple query language. When a query is requested, the server performs database access. When we have to access multiple fields in one query whether it is requested in a RESTful architecture or GraphQL, the varied resources and fields still have to be retrieved from a data source. So, it also shows the same problems when a client requests too many nested fields data at a single time. So there must be a mechanism like maximum query depths, query complexity weighting, avoiding recursion, or persistent queries to stop inefficient requests from the client-side.

2. GraphQL Caching

It is more complicated to implement a simplified cache with GraphQL than implementing it in REST. In REST API, we access resources with URLs, so we can cache on a resource level because we have the resource URL as an identifier. On the other hand, In GraphQL, it is very complex because each query can be different, even though it operates on the same entity. But most of the libraries built on top of GraphQL offer an efficient caching mechanism.

3. GraphQL Rate Limiting

Another problem with GraphQL is rate-limiting. In REST API, you can simply specify that we allow only this amount of requests in one day", but in GraphQL, it is difficult to specify this type of statement.