split captcha API url and captcha public URL

Author: ForestJohnson

README.md

@@ -111,14 +111,15 @@ The hexadecimal string which was obtained by [creating a new API token on the 
 
 ----
 
-#### COMMENTS_CAPTCHA_URL
+#### COMMENTS_CAPTCHA_API_URL
+
+Used to contact the captcha server & get captcha challenges
 
-Currently this variable is used for two different things.
+----
 
-1. It is used to contact the captcha server & get captcha challenges.
-2. It is used to load the captcha JavaScript and CSS into the page.
+#### COMMENTS_CAPTCHA_URL
 
-For that reason, this URL must be reachable from both the comments server and the public internet at large. This may change in the future, let me know if this causes a problem for you. Or you can just fix it yourself 😇
+Used to load the captcha JavaScript and CSS into the page
 
 ----
 

build-docker.sh

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 
-VERSION="0.1.45"
+VERSION="0.1.46"
 
 rm -rf dockerbuild || true
 mkdir dockerbuild

main.go

@@ -63,7 +63,8 @@ type CommentedDocument struct {
 var origins []string
 var portString = "$COMMENTS_LISTEN_PORT"
 var captchaAPIToken = "$COMMENTS_CAPTCHA_API_TOKEN"
-var captchaAPIURLString = "$COMMENTS_CAPTCHA_URL"
+var captchaAPIURLString = "$COMMENTS_CAPTCHA_API_URL"
+var captchaPublicURLString = "$COMMENTS_CAPTCHA_PUBLIC_URL"
 var commentsBasePath = "$COMMENTS_BASE_PATH"
 var commentsURLString = "$COMMENTS_BASE_URL"
 
@@ -72,6 +73,7 @@ var commentsURLString = "$COMMENTS_BASE_URL"
 var captchaDifficultyLevelString = "$COMMENTS_CAPTCHA_DIFFICULTY_LEVEL"
 var captchaDifficultyLevel int
 var captchaAPIURL *url.URL
+var captchaPublicURL *url.URL
 var loadCaptchaChallengesMutex *sync.Mutex
 var captchaChallengesMutex *sync.Mutex
 var loadCaptchaChallengesMutexIsProbablyLocked = false
@@ -118,10 +120,17 @@ func main() {
 	log.Printf("Allowed CORS Origins: [\n%s\n]\n", strings.Join(origins, "\n"))
 
 	captchaAPIToken = os.ExpandEnv(captchaAPIToken)
+
 	captchaAPIURLString = os.ExpandEnv(captchaAPIURLString)
 	captchaAPIURL, err = url.Parse(captchaAPIURLString)
-	if err != nil {
-		panic(errors.Wrapf(err, "can't parse COMMENTS_CAPTCHA_URL '%s' as url", captchaAPIURLString))
+	if err != nil || captchaAPIURLString == "" {
+		panic(errors.Wrapf(err, "can't parse COMMENTS_CAPTCHA_API_URL '%s' as url", captchaAPIURLString))
+	}
+
+	captchaPublicURLString = os.ExpandEnv(captchaPublicURLString)
+	captchaPublicURL, err = url.Parse(captchaPublicURLString)
+	if err != nil || captchaPublicURLString == "" {
+		panic(errors.Wrapf(err, "can't parse COMMENTS_CAPTCHA_PUBLIC_URL '%s' as url", captchaPublicURLString))
 	}
 
 	captchaDifficultyLevelString = os.ExpandEnv(captchaDifficultyLevelString)
@@ -757,7 +766,7 @@ func returnCommentsList(response http.ResponseWriter, postID, couldNotPostReason
 		Comments         []*Comment `json:"comments"`
 		Error            string     `json:"error"`
 	}{
-		CaptchaURL:       captchaAPIURL.String(),
+		CaptchaURL:       captchaPublicURL.String(),
 		CaptchaChallenge: challenge,
 		Comments:         rootComments,
 		Error:            couldNotPostReason,