While both REST and gRPC can use HTTP/2 as the underlying protocol, there are several key differences between them:
Data Format: REST typically uses JSON for requests and responses, while gRPC uses Protocol Buffers (protobuf), which is a binary format. Protocol Buffers are more efficient in terms of both size and speed, which can lead to significant performance improvements in gRPC.
API Design: REST is based on standard HTTP methods like GET, POST, PUT, DELETE, etc., and it uses URLs to identify resources. On the other hand, gRPC is based on the concept of defining a service, specifying the methods that can be called remotely with their parameters and return types. This allows gRPC to provide a strongly typed API contract between the client and server.
Streaming: HTTP/2 enables bidirectional streaming of data, which gRPC can take full advantage of by supporting four types of RPCs: unary, server streaming, client streaming, and bidirectional streaming. REST, however, typically only supports request-response style communication.
Error Handling: In REST, you can use HTTP status codes to indicate the status of a request. In gRPC, the status of a gRPC call is returned as a status code, which is a more standardized and language-independent way of expressing error conditions.
Tooling and Support: REST has been around for a long time and has widespread support across many languages and platforms. It also has excellent browser support. gRPC, while it has good support across many languages, does not have as broad browser support as REST.
Versioning: REST APIs can be versioned using the URL or request headers. gRPC uses message-based versioning. If new fields are added to the message, older servers will simply ignore them, providing some level of forward compatibility.
Why call a function and not just have request and response body in proto file?
Calling a function through gRPC or calling an API endpoint over HTTP/REST are just two different ways of achieving the same goal: interacting with a remote server. Each approach has its own advantages and is better suited for certain use cases.
Here are some reasons why using gRPC (and thus calling functions) might be considered “better” in certain scenarios:
- Efficiency: gRPC uses Protocol Buffers for serialization, which is more efficient than JSON used in typical REST APIs. This can lead to performance benefits.
- Streaming: gRPC supports bidirectional streaming. This means you can send a stream of data from the client to the server, from the server to the client, or both ways at the same time. This isn’t easily achievable with traditional REST APIs.
- Strongly-Typed: With gRPC, you define your service methods and their request/response types in .proto files. This provides type safety, which can help prevent errors.
- Language Agnostic: gRPC allows you to define your service once (in a .proto file) and generate client and server stubs in multiple languages. This is great for polyglot microservices architecture.
- Built-in Features: gRPC comes with a lot of built-in features like authentication, load balancing, logging, and monitoring.
However, REST APIs over HTTP/JSON also have their own advantages like simplicity, ease of debugging, wide support across platforms and languages, and more. They are also more suitable for web development due to native browser support for HTTP/JSON.
In summary, the choice between REST and gRPC will depend on your specific use case. REST might be a better choice for public APIs or for cases where you need good browser support. gRPC could be a better choice for high-performance internal services, real-time APIs, or when you need advanced features like streaming.
In the end, whether to use gRPC or REST depends on the specific needs and constraints of your project.
To understand Grpc more can refer to this
