SOAP vs. REST vs. GraphQL: Difference Between Web API Services

An API is a set of programming code/instructions that enables data transmission between one software to another.

How does an API work?

As we know, data is typically stored on the server. To retrieve that data, we should know how an API talks to the database (that’s what an API does) to get the particular data that we want. It helps by receiving our requests and responding back with the data needed to the particular service or client.

For example: Suppose you type a URL into the browser to visit a webpage, you are effectively sending a request to a server for all the data needed to display that website. i.e you enter youtube.com in the URL and click on a particular video then you send a request to the server to access a video and start playing its content.

From now it is clear that what is an API, so further in this discussion we will discuss the different types of Web API.

What is SOAP?

SOAP is an acronym for Simple Object Access Protocol. SOAP is a protocol that came into existence before REST. The main reason due to which SOAP come into existence was to ensure that programs built-in different platforms or programming languages could exchange data in an easy way.

Benefits of using SOAP:

SOAP’s standard HTTP Protocol makes it easier for it operates across Firewalls without modification of the SOAP protocol itself. But because it uses a complex XML format it tends to be slow.

Risks with SOAP:

• SOAP only allows XML format for transfer data over the network.
• SOAP required more bandwidth.
• Last but not least the size of the message which gets transferred from client to server is large in size.

What is REST?

Unlike SOAP is a Protocol, REST is an API design architecture. It stands for Representational State Transfer. The key difference between SOAP and REST is SOAP uses service interfaces to expose the functionality while REST uses Uniform Service Locator to access the components.

Benefits of using REST:

• REST allows a greater variety of formats, whereas SOAP only supports XML.
• REST is stateless.
• Since SOAP messages are larger in size, they require large bandwidth which is the opposite in the case of REST.

NOTE:

Stateful VS Stateless

While discussing Web Service API it is required to know about stateful and stateless where SOAP is stateful while REST is stateless.

Suppose you want to access a website and your data is hosted on the server, so to access your data you need to send the request to the server with your email and password so if your credentials are valid then the server authenticates you and sets a specific variable called as session variable to true.

Which indicated that the user is authenticated and able to access their resources like visiting their profile, but now make this example in a real situation where there are more than one servers let consider 2 in this case so we know that one server creates a session variable to authenticate the user on their end but in some case due to load balancing request is send to another server where for the given user session variable is not set, it showing unauthenticated which is not so good approach.

So to deal with this situation a new approach came into existence stateless, in this approach after the server authenticated the user with their email/ username and password it assigned a token to the user.

So whenever a user sends a request to access a resource it needs to send the token in the header so the server can identify the user, in this case, authentication does not depend on the server so there is no such condition like above.

Risks with REST:

• REST doesn’t impose any kind of securities like SOAP. That is the main reason REST is very appropriate for Public available URLs.
• When we talk about confidential data transfer between client and server, REST is the worst mechanism.
• REST is stateless For example, if you had a purchasing site that had the mechanism of having a shopping cart, it is required to know the number of items in the shopping cart before the purchase has occurred. Unfortunately, the burden of maintaining this state lies on the client-side, due to which it just makes the client application heavier and difficult to maintain.

Difference between SOAP and REST:

SOAP can not use REST, since SOAP is a protocol where REST is an architectural pattern, whereas REST can make use of SOAP as an underlying protocol for web services because at the end REST is just an architectural pattern.

SOAP requires more bandwidth for its usage. Since SOAP Messages body contains a lot of information inside of it, so usually the amount of data transfer using SOAP is generally a lot. While REST doesn’t need much bandwidth when requests are sent to the server. REST messages mostly just consist of JSON messages.

What is GraphQL?

Like REST, GraphQL is also an Architecture design pattern for API. One of The primary differences between REST and GraphQL is that GraphQL is not dealing with dedicated resources.

Instead, everything is considered as a graph and thus is connected.

This means you can alter the request/query according to your exact need.

Let’s take an example to understand the concept of GraphQL, suppose we want to create a website for blogging, so in this website users want to create a post, view the post, and also want to delete the post.

Here I am not explaining how to create an API in GraphQL, but trying to help you understand the structure of APIs:

As from the above images we see that after the server the project on localhost it shows a GraphQL terminal called GraphQL Playground, where on the left side we see the query i.e which route we need to access like getALLPost, get a particular post, or even want to delete the post.

You can see the play button in the middle of the screen by clicking on this you can run the specific API available to you and on the right-hand side, you can see the output.

NOTE:

You noticed that all the APIs work on a single endpoint, and we only need to specify which API we want to run by passing it in the query, as well we can also decide in output which specific field we require.

Benefits of using GraphQL:

From the above discussion, it is clear that GraphQL has some advantages over REST as follows

• Fetching data with a single API call: The most difference between GraphQL and REST is that the latter is centered around individual endpoints, so to collect all needed data, a developer has to combine multiple endpoints. Whereas GraphQL focuses on the task itself, during this case, a developer can request the needed data with only one API call.
• No over- and under-fetching problems. REST responses are known for either containing an excessive amount of data or not enough of it, creating the necessity for an additional request. GraphQL solves this efficiency problem by fetching the precise data during a single request.

Risks with GraphQL:

• Overkill for small applications. While GraphQL is that the right solution for multiple microservices, you’d better choose REST architecture in case of an easy app. REST also can be a valuable approach for connecting resource-driven apps that don’t need the flexible queries offered by GraphQL.
• Performance issues with complex queries

Conclusion:

Both REST and GraphQL are architecture designs for creating API. The REST approach is always limited to dealing with a single resource. If you need data from 2 different resources you need to multi-round trips from the server.

Whereas the case of GraphQL approach is more flexible and overcomes the shortcomings of REST.

With the help of GraphQL query language, you can describe what exactly your response looks like as we see in the above images on GraphQL.

So in the end we conclude that the type of approach needed to create the web service API depends on the requirement of the project.