image/issuer customization

onboard.lua

@@ -16,13 +16,19 @@ minetest.register_chatcommand("otp_enable", {
     description = "Enable the otp verification",
     func = function(name)
         -- issuer name
-        local issuer = "Minetest"
-        if minetest.settings:get("server_name") ~= "" then
-            issuer = minetest.settings:get("server_name")
-        elseif minetest.settings:get("server_address") ~= "" then
-            issuer = minetest.settings:get("server_address")
+        local issuer = minetest.settings:get("otp.issuer") or "Minetest"
+        local server_name = minetest.settings:get("server_name")
+        local server_address = minetest.settings:get("server_address")
+        if server_name and server_name ~= "" then
+            issuer = server_name
+        elseif server_address and server_address ~= "" then
+            issuer = server_address
         end
 
+        -- authenticator image
+        local image = minetest.settings:get("otp.authenticator_image") or
+            "https://raw.githubusercontent.com/minetest/minetest/master/misc/minetest-xorg-icon-128.png"
+
         local secret_b32 = otp.get_player_secret_b32(name)
 
         -- url for the qr code
@@ -31,7 +37,7 @@ minetest.register_chatcommand("otp_enable", {
             "&issuer=" .. issuer ..
             "&period=30" ..
             "&secret=" .. secret_b32 ..
-            "&image=https://raw.githubusercontent.com/minetest/minetest/master/misc/minetest-xorg-icon-128.png"
+            "&image=" .. image
 
         local ok, code = otp.qrcode(url)
         if not ok then

readme.md

@@ -37,6 +37,11 @@ minetest.register_privilege("my_super_important_priv", {
 })
 ```
 
+# Settings
+
+* `otp.authenticator_image` The image to use in the QR code for the otp app (defaults to "https://raw.githubusercontent.com/minetest/minetest/master/misc/minetest-xorg-icon-128.png")
+* `otp.issuer` The issuer name, defaults to server name, address or just "Minetest"
+
 # Links / References
 
 * https://en.wikipedia.org/wiki/Time-based_one-time_password