How to read a path param with echo that can contain slashes?

[archit-harness]

Issue Description

Consider following example -

package main

import (
    "github.com/labstack/echo"
)
func main() {
    e := echo.New()

    e.Get("/:repo/:image/manifests/:reference", func(e *echo.Context) error {
        return nil
    })

    e.Run(":8080")
}

now i want the image field to contains slashes and be able to query 3 different path params, which are - repo, image and reference and only image can contain slashes.

How should i write my route?

Checklist

• Dependencies installed
• No typos
• Searched existing issues and docs

Expected behaviour

Actual behaviour

Steps to reproduce

Working code to debug

package main

func main() {
}

Version/commit

[aldas]

This is not possible with current router matching logic but you can achieve same result like that:

func main() {
	e := echo.New()

	e.Use(middleware.Logger())
	e.Use(middleware.Recover())

	// "/:repo/:image/manifests/:reference"
	e.GET("/:repo/:param", func(c echo.Context) error {
		param := c.Param("param")
		idx := strings.LastIndex(param, "/manifests/")
		if idx == -1 {
			return errors.New("invalid url")
		}
		image := param[0:idx]
		reference := param[idx+11:] // TODO: check if length is ok for idx+11
		
		repo := c.Param("repo")
		return c.JSON(http.StatusOK, map[string]string{
			"repo":      repo,
			"image":     image,
			"reference": reference,
		})
	})

	s := http.Server{
		Addr:    ":8080",
		Handler: e,
	}

	if err := s.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
		log.Fatal(err)
	}
}

[archit-harness]

Point is i had various routes for this for which i created different route file and handler which was clean.

Now to adopt this, would need to create switch/if cases based on whether param contains which field.

Like i have another route as -

g.GET("/:repo/:image/tags/list", handler.GetTags)

What do you recommend?

[aldas]

probably one handler that checks that param for specifics parts

	// "/:repo/:image/manifests/:reference"
	// "/:repo/:image/tags/list"
	e.GET("/:repo/:param", func(c echo.Context) error {
		repo := c.Param("repo")

		param := c.Param("param")
		idx := strings.LastIndex(param, "/manifests/")
		if idx != -1 {
			image := param[0:idx]
			reference := param[idx+11:] // TODO: check if length is ok for idx+11
			
			// call manifest handler ()
			return c.JSON(http.StatusOK, map[string]string{
				"repo":      repo,
				"image":     image,
				"reference": reference,
			})
		}

		idx = strings.LastIndex(param, "/tags/list")
		if idx == -1 {
			return errors.New("invalid url")
		}
		image := param[0:idx]

		// call tags list handler ()
		return c.JSON(http.StatusOK, map[string]string{
			"repo":  repo,
			"image": image,
		})
	})

This is limitation of Echo router. There exists routers that support regext etc. If this is a must-have feature then you are probably better of switching Echo with something else. Maybe https://github.com/go-chi/chi