Top 8 API Protocols: Understanding the Most Popular Choices
Tags: api, protocol
Published: 2023-12-22 02:58:10

### Transformative Progress in API Technology: A Deep Dive

The digital world's constant evolution has solidified the importance of **[Application Programming Interfaces (APIs)](https://apidog.com/blog/know-about-apis/)** as they ensure smooth interactions among distinct software systems.

Grounded in the insights from the "2023 Global API Status Report," we embark on an insightful examination of the leading API protocols that captivate developers around the globe. We ask: What makes these protocols the developers' top picks? Why this abundance? And how do these protocols operate?

Our in-depth guide will escort you through a detailed exploration of eight premier API protocols and specifications. We'll touch on their defining traits, realms of application, and employ practical scenarios to demonstrate their instrumental role in your tech projects:

### 1. REST (Representational State Transfer)

Rather than a protocol per se, REST embodies a conceptual framework for networked application creation. It suggests a collection of constraints shaping the interaction web services should uphold.

**[HTTP Verbs](https://apidog.com/blog/http-methods/):**  Via various HTTP verbs, clients can engage with a resource as shown below:

-   `GET /articles`: Fetch a collection of articles.
-   `GET /articles/{id}`: Acquire an article's details using its identifier.
-   `POST /articles`: Instigate the creation of an article.
-   `PUT /articles/{id}`: Modify an existing article identified by its ID.
-   `DELETE /articles/{id}`: Eradicate an article tied to its ID.

#### REST in Practice:

Imagine requesting user information from a REST-compliant API of a social network. One would execute a GET request that looks something like this:

```
GET https://api.sampleplatform.com/users/abc123
```

### 2. GraphQL

Pioneered by Facebook and now open-source, GraphQL serves as both a query language and a server-side runtime for APIs, allowing clients to extract precisely what they need, a contrast to the static data retrieval in genre-standard RESTful services.

- **[ GraphQL Tutorial: What is GraphQL](https://apidog.com/blog/what-is-graphql/)**

#### A Quick GraphQL Example:

Consider this GraphQL schema definition:

```
type Article {
  id: ID!
  headline: String!
  content: String!
  contributor: Author!
}

type Author {
  id: ID!
  fullname: String!
}

type Query {
  articles: [Article!]!
  contributors: [Author!]!
}
```

Using the above schema, a request for specific data would be structured thusly:

```
{
  articles {
    headline
    contributor {
      fullname
    }
  }
}
```

The corresponding server's data structure in reply would strictly conform to the request, exemplified as:

```
{
  "data": {
    "articles": [
      {
        "headline": "The Basics of GraphQL",
        "contributor": {
          "fullname": "Alice Anderson"
        }
      },
      {
        "headline": "Optimizing Your GraphQL Implementation",
        "contributor": {
          "fullname": "Bob Brown"
        }
      }
    ]
  }
}
```

### 3. SOAP (Simple Object Access Protocol)/Web Service

**[SOAP](https://apidog.com/articles/soap-protocol-guide-for-beginner/)** is a mature protocol for exchanging information within web service implementations across distinct network protocols, commonly HTTP and SMTP. As a messaging construct, it prescribes how to formulate communicative messages across systems.

#### SOAP Illustration:

SOAP messages are encapsulated in XML. Here’s a simple illustration:

```
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ex="http://example.com">
  <soapenv:Header/>
  <soapenv:Body>
    <ex:QueryUser>
      <ex:ID>123</ex:ID>
    </ex:QueryUser>
  </soapenv:Body>
</soapenv:Envelope>
```

### 4. WebSocket

WebSockets enable two-way communication paths that remain consistently open for real-time data transfer, distinguishing it from traditional HTTP's discrete request-response pattern.

- **[ What is WebSocket and How It Works](https://apidog.com/blog/what-is-websocket-and-how-it-works/)**

#### Using WebSocket:

In this JavaScript snippet, we demonstrate a WebSocket client's connection beginner:

```
// Assuming the server is awaiting on wss://example.com/connection
let connection = new WebSocket('wss://example.com/connection');

// Recognize successful connection
connection.onopen = function(event) {
  // Upon connection, convey a greeting
  connection.send('Good day, Server!');
};

// Reacting to server-sent messages
connection.onmessage = function(event) {
  console.log('New message:', event.data);
};

// Handling connection closure
connection.onclose = function(event) {
  console.warn('Connection to server lost');
};

// Dealing with possible errors
connection.onerror = function(error) {
  console.error('WebSocket error:', error);
};
```

### 5. Sockets

Software sockets serve as the interface for network communication between applications over differently located machines, an integral part of networking software.

#### Socket Example in Python:

A Python server-client scenario using sockets might look like this:

Server (`server.py`)

```
import socket

# Opening a socket
socket_server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# Server will listen at this address and port
address = ('localhost', 6000)
socket_server.bind(address)

# Begin listening, up to 5 queued connections
socket_server.listen(5)

print("Awaiting client connections...")

while True:
    # Accept client connection
    client, addr = socket_server.accept()
    
    with client:
        data = client.recv(1024)
        print(f"Received: {data.decode()}")

        # Echo the received data back to the client
        client.send(data)
```

### 6. SSE (Server-Sent Events)

The Server-Sent Events (**[SSE](https://apidog.com/articles/what-is-server-sent-events-sse/)**) paradigm enables servers to push real-time updates over an established HTTP connection, distinct from pull-based methods like polling.

#### Applying SSE:

A practical use of SSE might be in receiving live notifications whenever a user's social media feed has new posts.

### 7. gRPC (gRPC Remote Procedure Call)

Engineered by Google, gRPC is an efficient, high-performance system that helps to connect applications or services within a distributed network.

- **[What Is gRPC? Definition, Architecture, Pros & Cons](https://apidog.com/articles/what-is-grpc/)**

#### gRPC Implementation:

For a calculator service offering addition and subtraction, you'd write:

```
syntax = "proto3";

service Calculator {
  rpc Add(Numbers) returns (Result);
  rpc Subtract(Numbers) returns (Result);
}

message Numbers {
  int32 a = 1;
  int32 b = 2;
}

message Result {
  int32 total = 1;
}
```

### 8. MsgPack (MessagePack)

**[MessagePack](https://apidog.com/blog/api-client-messagepack/)** allows for compact serialization of binary data, supporting diverse data types for cross-platform communications.

#### MsgPack Usage:

Here’s how Python implements MsgPack serialization:

```
import msgpack

# An illustrative dataset
dataset = {"name": "Emma", "age": 40, "is_student": True}

# Binary serialization
serialized = msgpack.packb(dataset)
# And deserialization
restored = msgpack.unpackb(serialized)

print(f"Before: {dataset}")
print(f"After: {restored}")
```

### Conclusion: Apidog - The Universal API Crafting Suite

**[Apidog](https://apidog.com/)** brings together the functionalities needed to tackle various protocols detailed above into a single, comprehensive platform. With Apidog, managing different API types from creation to testing, mirroring the combined powers of **[Postman](https://apidog.com/blog/what-is-postman/)**, **[Swagger](https://apidog.com/articles/what-is-swagger/)**, Mockup, and JMeter, but all in a singular, streamlined tool.