Routes with variable number of path segments

[aceeric]

Folks - How would one go about matching routes with variable segments in which the left-most, and, the right-most have a fixed interpretation but the "inside" segments are everything else. E.g.:

docker pull docker.io/hello-world:latest.: left-most is registry, rightmost is tag, everything else is repository. Then that rule holds for all these:

docker pull docker.io/foo/bar:latest.
docker pull docker.io/foo/bar/baz:latest.
docker pull docker.io/foo/bar/baz/and/so/on:latest.

I currently handle this with explicit routes but I'm wondering if there's a more flexible way - such as one route with "wildcards". I'm generating the Echo code using oapi-codegen. OAPI 3 does not support this but if Echo did, that might lead me to move away from oapi at least in the short time. (I understand OAPI 4 is going to support this.)

[waleed-haider38]

Where I need to make my routes in echo framework.

[aldas]

You can get image name and tag by registering route with path variable and cut it in handler

package main

import (
	"errors"
	"fmt"
	"log/slog"
	"net/http"
	"strings"

	"github.com/labstack/echo/v4"
	"github.com/labstack/echo/v4/middleware"
)

func main() {
	e := echo.New()
	e.Use(middleware.RequestLogger())
	e.Use(middleware.Recover())

	e.GET(`/foo/:tag`, func(c echo.Context) error {
		before, after, ok := strings.Cut(c.Param(`tag`), ":")
		if !ok {
			return errors.New("path does not contain colon")
		}
		return c.JSON(http.StatusOK, map[string]string{
			"before": before,
			"after":  after,
		})
	})

	e.GET(`/foo/bar/baz\:latest`, func(c echo.Context) error {
		return c.String(http.StatusOK, fmt.Sprintf("Hello from: `%s`\n", c.Path()))
	})

	if err := e.Start(":8080"); err != nil {
		slog.Error(err.Error())
	}
}

if you want define route that contain : you need to escape it.

	e.GET(`/foo/bar/baz\:latest`, func(c echo.Context) error {
		return c.String(http.StatusOK, fmt.Sprintf("Hello from: `%s`\n", c.Path()))
	})

output:

x@home:~/code$ curl "http://localhost:8080/foo/bar:latest"
{"after":"latest","before":"bar"}
x@home:~/code$ curl "http://localhost:8080/foo/image:2025"
{"after":"2025","before":"image"}
x@home:~/code$ curl "http://localhost:8080/foo/bar/baz:latest"
Hello from: `/foo/bar/baz\:latest`
x@home:~/code$ 

[aceeric]

Thank you for replying. The "latest" was just an example - it could be anything (1.2.3, v2.3.4, v1.0-experimental, etc) I think there's no easy way except with explicit paths for the various permutations. Thanks again though.