📝 [Proposal]: Branching handlers and with rules

[dozheiny]

Feature Proposal Description

HTTP servers usually use HTTP methods (like GET, POST, and PATCH) to separate and isolate the requests sent to them.
I'm thinking about more ways to separate and isolate requests. For example, I could separate requests by specific header value or specific value on URL query.

Alignment with Express API

I didn't find anything

HTTP RFC Standards Compliance

Confirmed

API Stability

package main

import "github.com/gofiber/fiber/v2"

func main() {
	app := fiber.New()

	app.Get("/", handler1, rules.Header("foo", "bar"))
        app.Get("/", handler2, rules.Header("key", "value"))

	app.Listen(":3000")
}

func handler1(c *fiber.Ctx) error {
    return c.SendString("Hello, World!")
}

func handler2(c *fiber.Ctx) error {
    return c.SendString("Goodbye, World!")
}

> curl http://127.0.0.1:3000/ -H "foo:bar"
< Hello, World!

> curl http://127.0.0.1:3000/ -H "key:value"
< GoodBye, World!

Feature Examples

app.Get("/", handler1, rules.Header("foo", "bar"))
app.Get("/", handler2, rules.Header("key", "value"))


> curl http://127.0.0.1:3000/ -H "foo:bar"
< Hello, World!

> curl http://127.0.0.1:3000/ -H "key:value"
< GoodBye, World!

Checklist:

• I agree to follow Fiber's Code of Conduct.
• I have searched for existing issues that describe my proposal before opening this one.
• I understand that a proposal that does not meet these guidelines may be closed without explanation.

[gaby]

Pretty sure this would make the router slower, since checking headers is an expensive operation on top of checking the handler path.

[dozheiny]

It could be optional if it causes performance issues.

[JIeJaitt]

@dozheiny What are the situations in which this recommendation could be used in actual production development work?

[ReneWerner87]

right the performance should drop if you activate the feature because more checks are necessary

but still it is an interesting feature

@coderabbitai
please give examples where it is used in other languages and frameworks and show usage examples

[JIeJaitt]

coderabbitai doesn't seem to be giving any replies. @ReneWerner87 Can this bot be used like chatgpt inside a GitHub issue?

[ReneWerner87]

@coderabbitai please give examples where it is used in other languages and frameworks and show usage examples

[dozheiny]

@dozheiny What are the situations in which this recommendation could be used in actual production development work?

It can be used for different user types like admins and normal users.
For example, we have the GET /products HTTP/1.1 API.

It can route different users to different controllers by using a specific header value or something else.

[gaby]

I believe you can do this already using redirect

https://docs.gofiber.io/next/api/redirect

[dozheiny]

@gaby True, but my point is to reduce middleware implementations or redirections.

[gaby]

Only thing I can think off is adding a middleware named Rules. Changing the router/app to add this doesn't make sense given its a unique use-case.

This kind of access control is not normally done using headers. There's other middlewares that check auth headers to handle stuff like this.

[dozheiny]

It's okay; that was just an idea that came to mind. I think we can close the issue since there are no examples or implementations in other frameworks.