Handle webmention receiving

entry.go

@@ -206,7 +206,7 @@ func ReadEntry(url string) (entry *Entry, err error) {
 	if err != nil {
 		return
 	}
-	fileContent, err := ReadFile(filePath)
+	fileContent, err := ReadFileContent(filePath)
 	if err != nil {
 		return
 	}

gitea.go

@@ -8,18 +8,34 @@ import (
 	"io/ioutil"
 	"net/http"
 	"net/url"
+	"strings"
 )
 
-func CreateFile(path string, file string, name string) error {
-	message := map[string]interface{}{
-		"message": name,
-		"content": base64.StdEncoding.EncodeToString([]byte(file)),
+type GiteaCommitRequest struct {
+	Content string `json:"content"`
+	Message string `json:"message"`
+	SHA     string `json:"sha,omitempty"`
+}
+
+type GiteaReadRequest struct {
+	Type    string `json:"type"`
+	Content string `json:"content"`
+	SHA     string `json:"sha"`
+}
+
+type GiteaErrorResponse struct {
+	Message string `json:"message"`
+}
+
+func CreateFile(path string, file string, message string) error {
+	request := &GiteaCommitRequest{
+		Content: base64.StdEncoding.EncodeToString([]byte(file)),
+		Message: message,
 	}
-	bytesRepresentation, err := json.Marshal(message)
+	bytesRepresentation, err := json.Marshal(request)
 	if err != nil {
 		return errors.New("failed to marshal json before committing")
 	}
-	// TODO: handle file updating
 	resp, err := http.Post(GiteaEndpoint+url.QueryEscape(path)+"?access_token="+GiteaToken, "application/json", bytes.NewBuffer(bytesRepresentation))
 	if err != nil || resp.StatusCode != 201 {
 		return errors.New("failed to create file in repo")
@@ -27,26 +43,88 @@ func CreateFile(path string, file string, name string) error {
 	return nil
 }
 
-func ReadFile(path string) (fileContent string, err error) {
+func UpdateFile(path string, file string, message string) error {
+	existingFile, exists, err := ReadFile(path)
+	if err != nil {
+		return err
+	}
+	if !exists {
+		// File doesn't exist, create it
+		return CreateFile(path, file, message)
+	}
+	request := &GiteaCommitRequest{
+		Content: base64.StdEncoding.EncodeToString([]byte(file)),
+		Message: message,
+		SHA:     existingFile.SHA,
+	}
+	bytesRepresentation, err := json.Marshal(request)
+	if err != nil {
+		return errors.New("failed to marshal json before committing")
+	}
+	req, err := http.NewRequest(http.MethodPut, GiteaEndpoint+url.QueryEscape(path)+"?access_token="+GiteaToken, bytes.NewBuffer(bytesRepresentation))
+	if err != nil {
+		return errors.New("error making update request")
+	}
+	req.Header.Set("Content-type", "application/json")
+	client := &http.Client{}
+	resp, err := client.Do(req)
+	if err != nil || resp.StatusCode != 200 {
+		return errors.New("failed to update file in repo")
+	}
+	return nil
+}
+
+func ReadFile(path string) (response *GiteaReadRequest, exists bool, err error) {
+	exists = false
 	resp, err := http.Get(GiteaEndpoint + url.QueryEscape(path) + "?access_token=" + GiteaToken)
 	if err != nil || resp.StatusCode != 200 {
+		if resp != nil {
+			defer resp.Body.Close()
+			body, readErr := ioutil.ReadAll(resp.Body)
+			if readErr != nil {
+				err = errors.New("failed reading Gitea error response")
+				return
+			}
+			errorResponse := &GiteaErrorResponse{}
+			marshalErr := json.Unmarshal(body, &errorResponse)
+			if marshalErr != nil {
+				err = errors.New("failed parsing Gitea error response")
+				return
+			}
+			exists = !strings.Contains(errorResponse.Message, "does not exist")
+			if !exists {
+				return
+			}
+		}
 		err = errors.New("failed to read file in repo")
 		return
 	}
+	exists = true
 	defer resp.Body.Close()
 	body, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		err = errors.New("failed reading file in repo")
 		return
 	}
-	giteaResponseBody := struct {
-		Content string
-	}{}
-	err = json.Unmarshal(body, &giteaResponseBody)
+	response = &GiteaReadRequest{}
+	err = json.Unmarshal(body, &response)
 	if err != nil {
 		err = errors.New("failed parsing Gitea response")
 		return
 	}
+	return
+}
+
+func ReadFileContent(path string) (fileContent string, err error) {
+	giteaResponseBody, exists, err := ReadFile(path)
+	if err != nil {
+		return
+	}
+	if !exists {
+		// File doesn't exist, nothing to read
+		err = errors.New("file does not exist")
+		return
+	}
 	decodedBytes, err := base64.StdEncoding.DecodeString(giteaResponseBody.Content)
 	if err != nil {
 		err = errors.New("failed decoding file content")

main.go

@@ -3,96 +3,16 @@ package main
 import (
 	"log"
 	"net/http"
-	"strconv"
 	"strings"
 	"time"
 )
 
-func handleMicroPub(w http.ResponseWriter, r *http.Request) {
-	// a handler for GET requests, used for troubleshooting
-	if r.Method == "GET" {
-		if q := r.URL.Query().Get("q"); q == "syndicate-to" {
-			w.Header().Add("Content-type", "application/json")
-			w.WriteHeader(http.StatusOK)
-			_, _ = w.Write([]byte("[]"))
-			return
-		} else if url := r.URL.Query().Get("url"); q == "source" {
-			limit := r.URL.Query().Get("limit")
-			limitInt, err := strconv.Atoi(limit)
-			jsonBytes, err := QueryURL(url, limitInt)
-			if err != nil {
-				w.WriteHeader(http.StatusBadRequest)
-				_, _ = w.Write([]byte(err.Error()))
-				return
-			}
-			w.Header().Add("Content-type", "application/json")
-			w.WriteHeader(http.StatusOK)
-			_, _ = w.Write(jsonBytes)
-			return
-		} else {
-			w.Header().Add("Content-type", "application/json")
-			w.WriteHeader(http.StatusOK)
-			_, _ = w.Write([]byte("{}"))
-			return
-		}
-	}
-	// check if the request is a POST
-	if r.Method != "POST" {
-		w.WriteHeader(http.StatusMethodNotAllowed)
-		_, _ = w.Write([]byte("The HTTP method is not allowed, make a POST request"))
-		return
-	}
-	// check content type
-	contentType, err := GetContentType(r.Header.Get("content-type"))
-	if err != nil {
-		w.WriteHeader(http.StatusBadRequest)
-		_, _ = w.Write([]byte(err.Error()))
-		return
-	}
-	// Create entry
-	entry, err := CreateEntry(contentType, r)
-	if err != nil || entry == nil {
-		w.WriteHeader(http.StatusBadRequest)
-		if err != nil {
-			_, _ = w.Write([]byte(err.Error()))
-		} else {
-			_, _ = w.Write([]byte("There was an error creating the entry"))
-		}
-		return
-	}
-	if CheckAuthorization(entry, r.Header.Get("authorization")) {
-		location, err := WriteEntry(entry)
-		if err != nil {
-			w.WriteHeader(http.StatusBadRequest)
-			_, _ = w.Write([]byte("There was an error committing the entry to the repository"))
-			return
-		} else {
-			w.Header().Add("Location", location)
-			w.WriteHeader(http.StatusAccepted)
-			// Purge BunnyCDN in 10 seconds
-			go func() {
-				time.Sleep(10 * time.Second)
-				Purge(location)
-				// Send webmentions
-				go func() {
-					time.Sleep(3 * time.Second)
-					SendWebmentions(location)
-				}()
-			}()
-			return
-		}
-	} else {
-		w.WriteHeader(http.StatusForbidden)
-		_, _ = w.Write([]byte("Forbidden, there was a problem with the provided access token"))
-		return
-	}
-}
-
 func main() {
-	http.HandleFunc("/", handleMicroPub)
 	log.Println("Starting micropub server...")
 	log.Println("Current time: " + time.Now().Format(time.RFC3339))
 	log.Println("Blog URL: " + BlogUrl)
 	log.Println("Ignored URLs for Webmention: " + strings.Join(IgnoredWebmentionUrls, ", "))
+	http.HandleFunc("/micropub", HandleMicroPub)
+	http.HandleFunc("/webmention", HandleWebmention)
 	log.Fatal(http.ListenAndServe(":5555", nil))
 }

micropub.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"net/http"
+	"strconv"
+	"time"
+)
+
+func HandleMicroPub(w http.ResponseWriter, r *http.Request) {
+	// a handler for GET requests, used for troubleshooting
+	if r.Method == "GET" {
+		if q := r.URL.Query().Get("q"); q == "syndicate-to" {
+			w.Header().Add("Content-type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			_, _ = w.Write([]byte("[]"))
+			return
+		} else if url := r.URL.Query().Get("url"); q == "source" {
+			limit := r.URL.Query().Get("limit")
+			limitInt, err := strconv.Atoi(limit)
+			jsonBytes, err := QueryURL(url, limitInt)
+			if err != nil {
+				w.WriteHeader(http.StatusBadRequest)
+				_, _ = w.Write([]byte(err.Error()))
+				return
+			}
+			w.Header().Add("Content-type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			_, _ = w.Write(jsonBytes)
+			return
+		} else {
+			w.Header().Add("Content-type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			_, _ = w.Write([]byte("{}"))
+			return
+		}
+	}
+	// check if the request is a POST
+	if r.Method != "POST" {
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		_, _ = w.Write([]byte("The HTTP method is not allowed, make a POST request"))
+		return
+	}
+	// check content type
+	contentType, err := GetContentType(r.Header.Get("content-type"))
+	if err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	// Create entry
+	entry, err := CreateEntry(contentType, r)
+	if err != nil || entry == nil {
+		w.WriteHeader(http.StatusBadRequest)
+		if err != nil {
+			_, _ = w.Write([]byte(err.Error()))
+		} else {
+			_, _ = w.Write([]byte("There was an error creating the entry"))
+		}
+		return
+	}
+	if CheckAuthorization(entry, r.Header.Get("authorization")) {
+		location, err := WriteEntry(entry)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			_, _ = w.Write([]byte("There was an error committing the entry to the repository"))
+			return
+		} else {
+			w.Header().Add("Location", location)
+			w.WriteHeader(http.StatusAccepted)
+			// Purge BunnyCDN in 10 seconds
+			go func() {
+				time.Sleep(10 * time.Second)
+				Purge(location)
+				// Send webmentions
+				go func() {
+					time.Sleep(3 * time.Second)
+					SendWebmentions(location)
+				}()
+			}()
+			return
+		}
+	} else {
+		w.WriteHeader(http.StatusForbidden)
+		_, _ = w.Write([]byte("Forbidden, there was a problem with the provided access token"))
+		return
+	}
+}

webmention.go

@@ -1,11 +1,24 @@
 package main
 
 import (
+	"crypto/md5"
+	"encoding/json"
+	"errors"
+	"fmt"
 	"log"
+	"net/http"
+	"net/url"
 	"strings"
+	"time"
 	"willnorris.com/go/webmention"
 )
 
+type Mention struct {
+	Source string `json:"source"`
+	Target string `json:"target"`
+	Date   string `json:"date"`
+}
+
 func SendWebmentions(url string) {
 	client := webmention.New(nil)
 	dl, err := client.DiscoverLinks(url, ".h-entry")
@@ -42,4 +55,120 @@ LINKFILTER:
 		filteredLinks = append(filteredLinks, link)
 	}
 	return filteredLinks
+}
+
+func HandleWebmention(w http.ResponseWriter, r *http.Request) {
+	if r.Method != "POST" {
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		_, _ = w.Write([]byte("The HTTP method is not allowed, make a POST request"))
+		return
+	}
+	sourceUrl, err := url.Parse(r.FormValue("source"))
+	if err != nil || !(sourceUrl.Scheme == "http" || sourceUrl.Scheme == "https") {
+		err = errors.New("failed to parse webmention source URL")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	targetUrl, err := url.Parse(r.FormValue("target"))
+	if err != nil || !(sourceUrl.Scheme == "http" || sourceUrl.Scheme == "https") {
+		err = errors.New("failed to parse webmention target URL")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	// Check if urls don't equal
+	if sourceUrl.String() == targetUrl.String() {
+		err = errors.New("source and target equal")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	// Check if target is blog
+	if !strings.HasPrefix(targetUrl.String(), BlogUrl) {
+		err = errors.New("wrong webmention target")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	// Check response code for source
+	respCode, err := responseCodeForSource(sourceUrl.String())
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	if respCode < 200 || respCode >= 300 {
+		if respCode == 410 {
+			// Delete mention, because source is gone
+			// TODO: Implement deleteion
+			w.Header().Add("Location", targetUrl.String())
+			w.WriteHeader(http.StatusOK)
+			return
+		} else {
+			err = errors.New("source returned error")
+			w.WriteHeader(http.StatusBadRequest)
+			_, _ = w.Write([]byte(err.Error()))
+			return
+		}
+	}
+	// Check if source mentions target
+	if !sourceMentionsTarget(sourceUrl.String(), targetUrl.String()) {
+		err = errors.New("source doesn't mention target")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	mention := &Mention{
+		Source: sourceUrl.String(),
+		Target: targetUrl.String(),
+		Date:   time.Now().Format(time.RFC3339),
+	}
+	err = saveWebmention(mention)
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		_, _ = w.Write([]byte(err.Error()))
+		return
+	}
+	w.Header().Add("Location", targetUrl.String())
+	w.WriteHeader(http.StatusOK)
+	// Purge BunnyCDN in 10 seconds
+	go func() {
+		time.Sleep(10 * time.Second)
+		Purge(targetUrl.String())
+	}()
+	return
+}
+
+func responseCodeForSource(source string) (int, error) {
+	client := &http.Client{}
+	resp, err := client.Get(source)
+	if err != nil || resp == nil {
+		return 0, err
+	}
+	return resp.StatusCode, nil
+}
+
+func sourceMentionsTarget(source string, target string) bool {
+	client := webmention.New(nil)
+	dl, err := client.DiscoverLinks(source, "")
+	if err != nil {
+		return false
+	}
+	for _, link := range dl {
+		if link == target {
+			return true
+		}
+	}
+	return false
+}
+
+func saveWebmention(mention *Mention) (err error) {
+	bytesRepresentation, err := json.Marshal(mention)
+	if err != nil {
+		return errors.New("failed to marshal json before committing")
+	}
+	filePath := fmt.Sprintf("data/mentions/%x/%x.json", md5.Sum([]byte(mention.Target)), md5.Sum([]byte(mention.Source)))
+	err = UpdateFile(filePath, string(bytesRepresentation), "New webmention from "+mention.Source)
+	return
 }