Most software applications need to be able to connect to other code for several reasons. This can be anything from integration to adding new functionality. To make sure software can link with other applications and to ensure their integration into other programs, developers use APIs. This is why an Application Programming Interface is necessary for most software. Through their role as a bridge across systems, APIs enable individuals to access a variety of web services. Therefore, it's important to pick the appropriate technology to offer an API to your project.
Any organization that wants to share its application or platform with its users needs to use APIs. There are many ways of developing and fine-tuning APIs to make them the perfect fit for your application. One of the latest methods that programmers are using to design APIs is gRPC. Let's look at what gRPC is and its pros and cons.
What is gRPC?
gRPC stands for Google Remote Procedure Call. gRPC is an open-source RPC framework that is used to create scalable and quick APIs. It enables the development of networked systems and open communication between gRPC client and server applications. gRPC has been embraced by several top tech companies, including Google, IBM, Netflix, and more. The gRPC framework depends on cutting-edge tech stacks like HTTP/2, protocol buffers, and more for optimum API protection, high-performance remote procedure calls, and scalability.
What are RPCs?
RPC and REST - Representational State Transfer- have historically been two separate approaches to building APIs. Additionally, protocols like SOAP and GraphQL are also used for this purpose. Remote procedure calls let you write software as if it will run locally, although it might run on a different device.
They are the most conventionally used framework to design APIs. In contrast to a typical HTTP protocol call, an RPC employs a function call as the primary method of client-server interaction. RPC is a productive technique for creating APIs since the exchanges are simple, and the contents are lightweight. gRPC services also mimic this communication architecture. RPC employs IDL - Interface Definition Language to contract the data type and the methods that will be invoked. Adopted gRPC services from RPCs have become very popular in recent years.
Why were gRPC services developed?
As more enterprises open up channels for integration, it is getting difficult to link such software. RPC APIs are challenging to integrate and risky to distribute because they may disclose internal specifics. They are developed in many programming languages and are closely tied to the underlying framework.
This issue was addressed, and API accessibility was increased when the REST API was launched in 2000. Specifically, it gave users a consistent way to retrieve information indirectly through assets using standard HTTP techniques like GET, PUT, POST, and others. The primary distinction of RPC from the REST API is that with RPC, processes are addressed, but it isn't easy to forecast what the processes in various systems could be.
The REST API couldn't completely replace straightforward and lightweight RPC because it produced a great deal of metadata, even while it offered an enhanced format for dealing with many applications. This resulted in the eventual emergence of Facebook's GraphQL and Google's gRPC services.
Google built gRPC in 2015 as an addition to the RPC framework to connect numerous microservices architecture made with various techniques. gRPC was originally closely related to Google's core infrastructure but was eventually made open source and standardized for usage by the general public.
Overview of gRPC concepts
The utilization of cutting-edge technologies, which have high performance over JSON and XML and offer greater API integrity, is responsible for the creation and popularity of gRPC. Some of the gRPC concepts you should be aware of are:
Protocol buffers
Protocol buffers, also known as Protobuf, are serialization or deserialization standards that make it simple to define applications and automatically perform the code generation of client libraries. The most recent version, proto3, is simpler to use and offers the newest capabilities for gRPC.
.Proto files enable the gRPC services and communications among gRPC clients and server messages. The .proto file is loaded into memory at execution by the Protobuf compiler - protoc. This compiler builds gRPC client and gRPC server applications that employ the in-memory structure to serialize and deserialize the binary data. Each communication is sent and received between the user and remote service following code generation in gRPC.
As data is translated into a binary form and encrypted signals are smaller, parsing with Protobuf uses less CPU power for gRPC. Therefore, even on computers with a weaker CPU, such as cell phones, messages are sent more quickly with gRPC.
HTTP/2
gRPC service is built on HTTP/2, the version of HTTP/1.1 that has fewer limitations. Although it works with the older HTTP protocol, HTTP/2 has several sophisticated features for gRPC. This includes a binary framing layer, which divides each HTTP/2 query and replies into smaller messages and frames them in binary format to improve message delivery. Additionally, gRPC supports multiple requests and responses from the client and gRPC server in bidirectional full-duplex streaming.
HTTP/2 has a flow control method that allows for precise control of the RAM needed to buffer in-flight packets. It also offers header compression for gRPC services. Everything in HTTP/2 is encrypted before transmission, even headers, which provide high-performance remote procedure calls. gRPC provides both asynchronous and synchronous processing with HTTP/2, enabling the execution of various interactive and streamed RPC types.
With the help of all these characteristics of HTTP/2, gRPC services can utilize fewer resources, which leads to faster response times among cloud-based applications and gRPC services and greater battery life for gRPC clients operating on mobile devices.
Streaming
A crucial idea that gRPC supports is streaming, which allows for the execution of several processes inside a single request. gRPC makes this feasible through HTTP/2's multiplexing feature, which allows several responses or requests to be sent or received simultaneously over one TCP - Transmission Control Protocol - connection. The primary streaming formats are server-streaming RPCs, client-streaming RPCs, and bidirectional-streaming RPCs.
Channels
As opposed to HTTP/2 streams, which permit numerous simultaneous streams on a single request connection, a channel with gRPC supports multiple continuous streams across multiple requests. They are employed to build a client stub and give a mechanism to link to a gRPC server on a specific IP and port.
gRPC Architecture
The gRPC architecture consists of both a gRPC client and a gRPC server. Every gRPC client service contains a stub or an auto-generated file, which is akin to an interface that contains the active remote processes. The gRPC client initiates a local procedure call to a stub containing arguments to be forwarded to the gRPC server messages. The gRPC client stub then sends the query to the local client-time unit on the local computer after serializing the arguments using the Protobuf marshaling procedure.
The operating system uses the HTTP/2 protocol to communicate with the distant server computer. The server's OS accepts the messages and invokes the server stub process, which uses Protobuf to invoke the appropriate operation after decoding the incoming parameters. The client transport layer then receives the encrypted response from the server stub. The execution passes back to the caller after the gRPC client stub receives the response messages and unwraps the provided arguments.
Pros of gRPC
gRPC has several advantages over other API designing mechanisms. gRPC also improves upon the RPC structure. Here are the most prominent benefits of gRPC services:
- High performance remote procedure calls
Using Protobuf and HTTP/2, gRPC services provide up to 10 times the high performance and API protection of REST+JSON interaction. With the use of server pushes, multiplexing, and header compression, HTTP/2 provides high-performance rankings for gRPC services. While multiplexing does away with head-of-line delay, server push makes it possible for HTTP/2 to push material from the server to the client before it is required. The messages are compressed more effectively using HTTP/2, resulting in quicker loading with gRPC services.
- Streaming
The service description for streaming gRPC services already includes client- or server-end streaming principles. Building gRPC clients and streaming services are made significantly easier as a result.
- Code Generation
The code generation for gRPC client and gRPC server programs is the key component of the gRPC web approach. For code generation from the .proto file, gRPC modules employ the .protoc compiler. The Protobuf format is controlled through code generation in gRPC, which is used to define both data formats and application endpoints. It can create client-side network stubs and server-side skeletons, which reduces the amount of time needed to design programs with a variety of services in gRPC services.
- Interoperability
Numerous systems and programming languages, like Java, Ruby, Go, C#, and more, are supported by the gRPC resources and libraries. With these programming languages, developers can create performant apps while utilizing complete cross-platform compatibility with gRPC. This is thanks to the Protobuf binary wiring form and effective code generation for almost all systems.
- Security
API security is ensured in gRPC using HTTP/2 over a TLS end-to-end encrypted session. gRPC promotes the adoption of SSL/TLS for data encryption and authentication between the server and the gRPC client.
- Productivity and Usability
Since gRPC is a complete RPC alternative, it operates without a hitch on a wide range of systems and languages. gRPC also has great tooling, with a lot of the necessary boilerplate code being generated manually. Engineers can now concentrate more on core functionality because of the significant time savings with gRPC.
Cons of gRPC
Although we can hope that gRPC drawbacks will eventually get solved, they do pose some problems to its usage now. Some cons of gRPC you should be aware of are:
- Lack of maturity
A technology's development can be a significant barrier to adoption. That is also clear while using gRPC. GraphQL, one of gRPC's peers, has more than 14k queries on StackOverflow, while gRPC only has a bit below 4k at the moment. The gRPC community lacks knowledge of best practices, solutions, and successes because there isn't much programmer assistance for HTTP/2, as well as protocol buffers outside of Google. However, as the gRPC community expands and draws in new developers, this will eventually evolve.
- Limited browser support
As no current gRPC web browser can handle HTTP/2 frames, you can't effectively call a gRPC service from a browser since gRPC Web primarily depends on HTTP/2. As a result, you must utilize a proxy with gRPC, which comes with several drawbacks.
- Unreadable by humans
Unlike XML and JSON, Protobuf files are not human-readable since data is compressed to a binary format. Developers must make use of additional tools, such as the server reflection protocol and gRPC command prompt to evaluate payloads, carry out troubleshooting, and create manual queries.
- Steep learning curve
It will take a while to become familiar with protocol buffers and discover methods for coping with HTTP/2 friction, in contrast to REST and GraphQL, both of which mostly employ JSON.
How does AppMaster help?
No-code generation is changing the way people view programming. No-code generation makes it possible for people to learn and create software faster with code generation. Code generation for your application is simpler using no-code generation platforms like AppMaster. There are no ownership issues either, as the code generation is protected, and the code you create will belong solely to you. You can create client and server applications faster and more easily with AppMaster.
AppMaster's no-code generation platform lets developers use the gRPC protocol to make requests between backend microservices architecture. Next year we will extend gRPC support by including API to both gRPC Web and gRPC Mobile applications.
Conclusion
Although gRPC services have several benefits that make them attractive to businesses and developers, finally, the decision to use gRPC services over others like REST or SOAP depends on your application. While some software will have high-performance benefits with gRPC, others might be better suited to its alternatives. You should understand the drawbacks and advantages of gRPC services and decide whether it works for you.
