Router not working with custom methods after parameter

[dalmarcolucas]

Issue Description

Router Find not working with "custom methods".
It seems that the fix made in issue #2046, does not deal with routes that have a custom method after parameter, (examples in the code below)

Checklist

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

Expected behaviour

Match routes with custom actions and parameters

Actual behaviour

Overwriting routes, when it should treat as a different route

Steps to reproduce

Code bellow

Working code to debug

package main

import (
	"strings"
	"testing"

	"github.com/labstack/echo/v4"
	"github.com/stretchr/testify/assert"
)

func TestEscape(t *testing.T) {
	e := echo.New()

	router := echo.NewRouter(e)

	router.Add(strings.ToUpper("PUT"), "/api/users/:id", void)
	router.Add(strings.ToUpper("POST"), "/api/users/:id\\:customAction", void)
	router.Add(strings.ToUpper("POST"), "/api/users/:id\\:otherAction", void)

	echoContext := e.NewContext(nil, nil)

	router.Find("GET", "/api/users/123", echoContext)
	genericRoute := echoContext.Path()
	assert.Equal(t, "/api/users/:id", genericRoute)

	router.Find("POST", "/api/users/123:customAction", echoContext)
	genericRouteCustomAction := echoContext.Path()
	assert.Equal(t, "/api/users/:id:customAction", genericRouteCustomAction)

	router.Find("POST", "/api/users/123:otherAction", echoContext)
	genericRouteOtherAction := echoContext.Path()
	assert.Equal(t, "/api/users/:id:otherAction", genericRouteOtherAction)

      //All "Finds" calls return the "/api/users/:id\\:otherAction" route
}

func void(c echo.Context) error {
	return nil
}

Version/commit

v4.9.0

[aldas]

At the moment \\:verb only work when path part between slashes is static. Basically \\: means that : is not considered as start of path parameter when route is added. When there is a parameter i.e. :id between slashes its name is parsed always to the next slash or end of the route path. So in case of "/api/users/:id\\:otherAction" the parameter name that is registered for route is actually id\:otherAction.

Routes "/api/users/:id\\:customAction" and "/api/users/:id\\:otherAction" are parsed as /api/users/: path to be matched for router and their only difference is that parameter name is different - therefore latter overwrites former when you add those routes.

I would say this is working as intended - due to the limitations or design choices how parameters work.

[dalmarcolucas]

@aldas thanks! It makes sense, I agree its working as intended, but at the moment, there is maybe a workaround that would make the router match work for these routes now?
And will this match be possible in the future?

[aldas]

I think currently you need to resort to (maybe) creating POST route for path /api/users/:idverb and inside that handler split parameter idverb into two and then have a switch statement for each verb types.

something like that:

func otherAction(c echo.Context, id int64) error {
	return c.JSON(http.StatusOK, map[string]int64{"id": id})
}

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

	e.GET("/api/users/:idverb", func(c echo.Context) error {
		idStr, verb, ok := strings.Cut(c.Param("idverb"), ":")
		if !ok {
			return echo.NewHTTPError(http.StatusBadRequest, "missing verb")
		}
		id, err := strconv.ParseInt(idStr, 10, 64)
		if err != nil {
			return echo.NewHTTPError(http.StatusBadRequest, "invalid id value")
		}

		switch verb {
		case "otherAction":
			return otherAction(c, id)
		default:
			return echo.NewHTTPError(http.StatusBadRequest, "invalid verb value")
		}
	})

	if err := e.Start(":8080"); err != http.ErrServerClosed {
		e.Logger.Fatal(err)
	}
}

this is not that eloquent but should work.

[dalmarcolucas]

Thanks again @aldas, but actually I have one permission service, where with base on the specific request, I need to find the generic route to check if the user has permission to access the endpoint. So this workarround wont work for me.

I changed to mux that works as expected with custom methods