ratchet/internal/server/base_server.go

package server

import (
	"fmt"
	"html/template"
	"log/slog"
	"net/http"
	"strconv"

	"git.runcible.io/learning/ratchet/internal/domain/user"
)

type RatchetServer struct {
	http.Handler

	logger *slog.Logger
	//Services used by HTTP routes
	UserService user.UserService
}

func NewRatchetServer(logger *slog.Logger) *RatchetServer {
	rs := new(RatchetServer)
	rs.logger = logger
	// TODO implement middleware that disables directory listings
	fileServer := http.FileServer(http.Dir("./ui/static/"))
	router := http.NewServeMux()

	// Subtree pattern for static assets
	router.Handle("GET /static/", http.StripPrefix("/static/", fileServer))

	// /{$} is used to prevent subtree path patterns from acting like a wildcard
	// resulting in this route requiring an exact match on "/" only
	// You can only include one HTTP method in a route pattern if you choose
	// GET will match GET & HEAD http request methods
	router.HandleFunc("GET /{$}", rs.home)
	router.HandleFunc("GET /snippet/view/{id}", rs.snippetView)
	router.HandleFunc("GET /snippet/create", rs.snippetCreate)

	// FYI The http.HandlerFunc() adapter works by automatically adding a ServeHTTP() method to
	// the passed function
	router.HandleFunc("POST /snippet/create", rs.snippetCreatePost)

	// Mux Router implements the Handler interface. AKA it has a ServeHTTP receiver.
	rs.Handler = router
	return rs
}

func (rs *RatchetServer) home(w http.ResponseWriter, r *http.Request) {
	// TODO middleware should be able to print out these lines for all routes
	rs.logger.Info("request received", "method", "GET", "path", "/")

	w.Header().Add("Server", "Go")

	// Initialize a slice containing the paths to the two files. It's important
	// to note that the file containing our base template must be the *first*
	// file in the slice.
	files := []string{
		"./ui/html/base.go.tmpl",
		"./ui/html/partials/nav.go.tmpl",
		"./ui/html/pages/home.go.tmpl",
	}

	// read template file into template set.
	ts, err := template.ParseFiles(files...)
	if err != nil {
		rs.serverError(w, r, err)
		return
	}
	// Write template content to response body
	err = ts.ExecuteTemplate(w, "base", nil)
	if err != nil {
		// This is the older more verbose way of doing what RatchetServer.serverError does
		// rs.logger.Error(err.Error())
		// http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		rs.serverError(w, r, err)
	}
}

func (rs *RatchetServer) snippetView(w http.ResponseWriter, r *http.Request) {

	id, err := strconv.Atoi(r.PathValue("id"))
	if err != nil || id < 1 {
		// http.NotFound(w, r)
		rs.clientError(w, http.StatusNotFound)
		return
	}

	// Set a new cache-control header. If an existing "Cache-Control" header exists
	// it will be overwritten.
	w.Header().Set("Cache-Control", "public, max-age=31536000")

	// msg := fmt.Sprintf("Snippet %d...", id)

	// w.Write([]byte(msg))

	// we can rely on the Write() interface to use a differnent
	// function to write out our response

	fmt.Fprintf(w, "Snippet %d...", id)
}

// snippetCreate handles display of the form used to create snippets
func (rs *RatchetServer) snippetCreate(w http.ResponseWriter, r *http.Request) {
	w.Write([]byte("Displaying snippetCreate form..."))
}

// snippetCreate handles display of the form used to create snippets
func (rs *RatchetServer) snippetCreatePost(w http.ResponseWriter, r *http.Request) {
	// example of a custom header. Must be done before calling WriteHeader
	// or they will fail to take effect.
	w.Header().Add("Server", "Dirp")
	w.WriteHeader(http.StatusCreated)

	w.Write([]byte("Created snippet..."))
}