Use minetest's JSON functions instead of external library

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "lua-json"]
-	path = lua-json
-	url = https://git.noordstar.me/Bram/lua-json.git

README.md

@@ -7,7 +7,7 @@ This repository serves as a bridge between Matrix and Minetest servers.
 1. Clone this repository into your Minetest mods folder:
 
 ```sh
-git clone --recursive https://git.noordstar.me/Bram/mt-matrix.git
+git clone https://git.noordstar.me/Bram/mt-matrix.git
 ```
 
 2. To access the Matrix homeserver, this mod needs access to HTTP calls. Add this mod to your `minetest.conf` settings at the field `secure.http_mods`:

init.lua

@@ -17,13 +17,6 @@ end
 -- Load standard configuration
 load("config")
 
--- Load JSON module
-json = nil
-load("lua-json/json")
-if json == nil then
-    error("Failed to load JSON module")
-end
-
 -- Load Matrix modules
 matrix = {}
 load("lua/send")

lua-json

@@ -1 +0,0 @@
-Subproject commit 261adde7a76687db142641d50cf4ed29873ec476

lua/send.lua

@@ -8,7 +8,7 @@ function matrix.send_message(http_api, body, formatted_body, callback, txnId)
             config.url .. "/_matrix/client/v3/rooms/" .. config.room_id ..
             "/send/m.room.message/" .. txnId
         ),
-        data = json.encode({
+        data = minetest.write_json({
             msgtype = "m.text",
             body = body,
             format = "org.matrix.custom.html",
@@ -22,7 +22,7 @@ function matrix.send_message(http_api, body, formatted_body, callback, txnId)
             minetest.debug(result.data)
         else
             if callback ~= nil then
-                callback(json.decode(result.data))
+                callback(minetest.parse_json(result.data))
             end
         end
     end)

lua/sync.lua

@@ -22,7 +22,7 @@ function matrix.sync(http_api, callback, global_callback)
             minetest.debug("Failed to sync with Matrix server; received code " .. result.code)
             minetest.debug(result.data)
         else
-            local answer = json.decode(result.data)
+            local answer = minetest.parse_json(result.data)
             
             if answer.next_batch ~= nil then
                 sync_so_far = answer.next_batch