Advanced API Technologies What is gRPC?# gRPC (Google Remote Procedure Call) is an open-source high-performance RPC framework that runs over HTTP/2 . It was released by Google in 2015.REST APIs typically use JSON (a text-based format) over HTTP/1.1. In contrast, gRPC uses Protocol Buffers (Protobuf), a binary format, to serialize data. This results in smaller payloads and faster processing, making gRPC ideal for low-latency communication between microservices. Core Concepts# 1.
Protocol Buffers (Protobuf) : The Interface Definition Language (IDL) used to define the service API and payload messages.
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HTTP/2 Transport : Enables multiplexing (multiple requests over one connection), header compression, and server push.
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Strict Contract : The .proto file acts as the single source of truth. Both client and server code are generated from this definition.
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Streaming : Native support for streaming data in both directions.
Code Example: The .proto Contract# Everything starts with a definition file: The 4 Communication Modes# 1.
Unary RPC : The client sends a single request and gets a single response. (Similar to a standard function call or REST request).
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Server Streaming : The client sends a request and receives a stream of messages. The client reads until there are no more messages.
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Client Streaming : The client writes a sequence of messages to the server. Once finished, the server sends a single response.
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Bidirectional Streaming : Both sides send a sequence of messages using a read-write stream. The two streams operate independently.
Comparisons: gRPC vs. REST# Feature REST gRPC Protocol HTTP/1.1 (usually) HTTP/2 Payload JSON / XML (Text) Protobuf (Binary) Contract Optional (OpenAPI) Required (.proto) Streaming Limited (Chunked transfer) Native (Bi-directional) Browser Support Universal Limited (requires gRPC-Web proxy) Use Case Public APIs, Web Clients Internal Microservices, Mobile Apps
Working with gRPC in Apidog# Apidog simplifies the complexity of testing binary gRPC endpoints by providing a user-friendly interface. 1. Create a gRPC Project# Select New Project -> gRPC Project . Apidog handles gRPC separately to optimize for its specific lifecycle. 2. Import Definition (.proto)# You don't manually type endpoints in gRPC. 2.
Import .proto : Upload your local file.
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Server Reflection : If your server supports reflection, enter the URL, and Apidog will auto-discover available services.
3. Invoking Methods# Apidog translates your JSON input into Protobuf binary automatically. Select the method from the sidebar.
Enter parameters in the JSON body editor.
For streaming methods, the Timeline View is essential. It shows the exact sequence of messages sent and received, allowing you to debug race conditions or timing issues in real-time. Key Takeaways# High Performance : gRPC uses Protocol Buffers (binary) and HTTP/2 for low-latency, high-throughput communication.
Strict Contracts : The .proto file is the source of truth, allowing code generation for both client and server.
Streaming : Native support for Server, Client, and Bidirectional streaming makes it ideal for real-time data feeds.
Apidog Support : Apidog handles the binary encoding complexities for you, allowing you to test gRPC with simple JSON inputs.
Modified atΒ 2025-12-25 10:12:25
