api,frontend: add unsubscribe

api/email_get.go

@@ -1,6 +1,8 @@
 package main
 
-import ()
+import (
+	"net/http"
+)
 
 func emailGet(em string) (email, error) {
 	statement := `
@@ -18,3 +20,40 @@ func emailGet(em string) (email, error) {
 
 	return e, nil
 }
+
+func emailGetByUnsubscribeSecretHex(unsubscribeSecretHex string) (email, error) {
+	statement := `
+		SELECT email, unsubscribeSecretHex, lastEmailNotificationDate, pendingEmails, sendReplyNotifications, sendModeratorNotifications
+		FROM emails
+		WHERE unsubscribeSecretHex = $1;
+	`
+	row := db.QueryRow(statement, unsubscribeSecretHex)
+
+	e := email{}
+	if err := row.Scan(&e.Email, &e.UnsubscribeSecretHex, &e.LastEmailNotificationDate, &e.PendingEmails, &e.SendReplyNotifications, &e.SendModeratorNotifications); err != nil {
+		// TODO: is this the only error?
+		return e, errorNoSuchUnsubscribeSecretHex
+	}
+
+	return e, nil
+}
+
+func emailGetHandler(w http.ResponseWriter, r *http.Request) {
+	type request struct {
+		UnsubscribeSecretHex *string `json:"unsubscribeSecretHex"`
+	}
+
+	var x request
+	if err := bodyUnmarshal(r, &x); err != nil {
+		bodyMarshal(w, response{"success": false, "message": err.Error()})
+		return
+	}
+
+	e, err := emailGetByUnsubscribeSecretHex(*x.UnsubscribeSecretHex)
+	if err != nil {
+		bodyMarshal(w, response{"success": false, "message": err.Error()})
+		return
+	}
+
+	bodyMarshal(w, response{"success": true, "email": e})
+}