Gleece - Rest API Development in Go

Following the recent articles about building and coding an I/S with Services API, Frontend, SDK, etc.

The key point demonstrated was the high importance of enabling developers to easily write their own controllers as functions, define annotations, and have the build and CI/CD processes generate the specification standards, routing, validations, APIs, and SDKs from the source code itself - maintaining a single source of truth.

In the previous articles, I have demonstrated how to achieve this using TSOA for TypeScript with OpenAPI schema and tools.

The most amazing aspect of TSOA, from my point of view, is that unlike other frameworks, it focuses on the API development itself, and FROM it generates whatever is necessary (such as OpenAPI), instead of adjusting the API development structure to align with OpenAPI specifications.

Recently, we started working with Go, an amazing and well-designed programming language (unlike JS... XD), and we wanted to integrate it with our I/S and CI/CD processes.

Coming from the TypeScript ecosystem, we were inspired by frameworks like TSOA that handle everything from routing and validation to OpenAPI generation - all from a single source of truth: your code.

And while these core features are amazing, TSOA's true power lies in its flexibility - allowing easy customization for any real-world use-case while allowing bypassing the tool back to the native router when necessary.

Therefore, we decided to implement such a solution to provide the Golang community with the same powerful API development capabilities we had in the TypeScript ecosystem.

Our design considers the following:

• Focus on ease of development - create simple functions, add annotations, and you're ready to go
• Easy & fault-safe security mechanism - allows default policies, aborts & fails builds for missing route security, and one, unified simple function to be called with HTTP object and security checks to do authorization check.
• Support for Go's standard validation with custom validation - easily validate every aspect of the request, path, query, header, and struct content in API body
• Generate specifications from the code - supports OpenAPI specification 3.0 & 3.1 with an interface to add future versions
• Effortless integration with common routers - Supports all popular Go routers (Gin, Echo v4, Gorilla Mux, Chi v5, and Fiber v2) for both new and existing services. Easily extendable to support additional router frameworks through customizable router templates.
• Easy error handling behavior - uses RFC7807 by default while allowing custom errors
• Clean and clear route and HTTP properties declaration - while allowing advanced usage with access to the HTTP context, set headers, status, etc.
• Built for customization - Designed to be highly customizable, supporting real-world specific service needs (e.g. integrating telemetry into generated routes with API-declared objects)
• Extend, don't replace - While providing powerful features, we ensure developers maintain access to the underlying context and can easily bypass the framework when needed

We incorporated all these requirements into the Gleece project.

Gleece is designed to provide Go developers with all these capabilities.

How does it work? Let's GO:

1 - Create a Gin/Echo service in Go

2 - Write your controllers and structs, set annotations with all required info (HTTP request, response, headers, validations, documentation, security, etc.)

3 - Implement your security check function

4 - Define your Gleece configuration (OpenAPI version, router engine, security function package, output path, etc.)

5 - Run Gleece CLI to generate routes & API specifications

6 - Import generated routes and register them into your engine's router of choice

7 - Run your server

That's all.

Sounds good?

Go ahead and check out the Gleece Repository Gleece documentation docs.gleece.dev and the complete Gleece Service Example

💡 Pro Tip: Install our VSCode Extension for a full coding viability support!

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Special thanks to my colleague and friend Yuval Pomerchik for the initiative and massive contribution to this project.