owl-blogs/cmd/owl/web/handler.go

package web

import (
	"h4kor/owl-blogs"
	"net/http"
	"os"
	"path"
	"strings"

	"github.com/julienschmidt/httprouter"
)

func getUserFromRepo(repo *owl.Repository, ps httprouter.Params) (owl.User, error) {
	if config, _ := repo.Config(); config.SingleUser != "" {
		return repo.GetUser(config.SingleUser)
	}
	userName := ps.ByName("user")
	user, err := repo.GetUser(userName)
	if err != nil {
		return owl.User{}, err
	}
	return user, nil
}

func repoIndexHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
		html, err := owl.RenderUserList(*repo)

		if err != nil {
			println("Error rendering index: ", err.Error())
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte("Internal server error"))
			return
		}
		println("Rendering index")
		w.Write([]byte(html))
	}
}

func userIndexHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		user, err := getUserFromRepo(repo, ps)
		if err != nil {
			println("Error getting user: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		html, err := owl.RenderIndexPage(user)
		if err != nil {
			println("Error rendering index page: ", err.Error())
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte("Internal server error"))
			return
		}
		println("Rendering index page for user", user.Name())
		w.Write([]byte(html))
	}
}

func userWebmentionHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		user, err := getUserFromRepo(repo, ps)
		if err != nil {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("User not found"))
			return
		}
		err = r.ParseForm()
		if err != nil {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("Unable to parse form data"))
			return
		}
		params := r.PostForm
		target := params["target"]
		source := params["source"]
		if len(target) == 0 {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("No target provided"))
			return
		}
		if len(source) == 0 {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("No source provided"))
			return
		}

		if len(target[0]) < 7 || (target[0][:7] != "http://" && target[0][:8] != "https://") {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("Not a valid target"))
			return
		}

		if len(source[0]) < 7 || (source[0][:7] != "http://" && source[0][:8] != "https://") {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("Not a valid source"))
			return
		}

		if source[0] == target[0] {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("target and source are equal"))
			return
		}

		parts := strings.Split(target[0], "/")
		if len(parts) < 2 {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("Not found"))
			return
		}
		postId := parts[len(parts)-2]
		post, err := user.GetPost(postId)
		if err != nil {
			w.WriteHeader(http.StatusBadRequest)
			w.Write([]byte("Post not found"))
			return
		}
		err = post.AddIncomingWebmention(source[0])
		if err != nil {
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte("Unable to process webmention"))
			return
		}

		w.WriteHeader(http.StatusAccepted)
		w.Write([]byte(""))
	}
}

func userRSSHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		user, err := getUserFromRepo(repo, ps)
		if err != nil {
			println("Error getting user: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		xml, err := owl.RenderRSSFeed(user)
		if err != nil {
			println("Error rendering index page: ", err.Error())
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte("Internal server error"))
			return
		}
		println("Rendering index page for user", user.Name())
		w.Header().Set("Content-Type", "application/rss+xml")
		w.Write([]byte(xml))
	}
}

func postHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		postId := ps.ByName("post")

		user, err := getUserFromRepo(repo, ps)
		if err != nil {
			println("Error getting user: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		post, err := user.GetPost(postId)

		if err != nil {
			println("Error getting post: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}

		meta := post.Meta()
		if meta.Draft {
			println("Post is a draft")
			notFoundHandler(repo)(w, r)
			return
		}

		html, err := owl.RenderPost(&post)
		if err != nil {
			println("Error rendering post: ", err.Error())
			w.WriteHeader(http.StatusInternalServerError)
			w.Write([]byte("Internal server error"))
			return
		}
		println("Rendering post", postId)
		w.Write([]byte(html))

	}
}

func postMediaHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request, httprouter.Params) {
	return func(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
		postId := ps.ByName("post")
		filepath := ps.ByName("filepath")

		user, err := getUserFromRepo(repo, ps)
		if err != nil {
			println("Error getting user: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		post, err := user.GetPost(postId)
		if err != nil {
			println("Error getting post: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		filepath = path.Join(post.MediaDir(), filepath)
		if _, err := os.Stat(filepath); err != nil {
			println("Error getting file: ", err.Error())
			notFoundHandler(repo)(w, r)
			return
		}
		http.ServeFile(w, r, filepath)
	}
}

func notFoundHandler(repo *owl.Repository) func(http.ResponseWriter, *http.Request) {
	return func(w http.ResponseWriter, r *http.Request) {
		path := r.URL.Path
		aliases, _ := repo.PostAliases()
		if _, ok := aliases[path]; ok {
			http.Redirect(w, r, aliases[path].UrlPath(), http.StatusMovedPermanently)
			return
		}
		w.WriteHeader(http.StatusNotFound)
		w.Write([]byte("Not found"))
	}
}