Function Http_Request

engine/gamesys/src/gamesys/scripts/script_http.cpp:133–289

perform a HTTP/HTTPS request * Perform a HTTP/HTTPS request. * * [icon:attention] If no timeout value is passed, the configuration value "network.http_timeout" is used. If that is not set, the timeout value is `0` (which blocks indefinitely). * * @name http.request * @param url [type:string] target url * @param method [type:string] HTTP/HTTPS method, e.g. "GET",

     * ```
     */
    static int Http_Request(lua_State* L)
    {
        int top = lua_gettop(L);

        dmMessage::URL sender;
        if (dmScript::GetURL(L, &sender)) {

            const char* url = luaL_checkstring(L, 1);
            const uint32_t max_url_len = dmURI::MAX_URI_LEN;
            const uint32_t url_len = (uint32_t)strlen(url);
            if (url_len > max_url_len)
            {
                assert(top == lua_gettop(L));
                return luaL_error(L, "http.request does not support URIs longer than %d characters.", max_url_len);
            }

            const char* method = luaL_checkstring(L, 2);
            const uint32_t max_method_len = 16;
            const uint32_t method_len = (uint32_t)strlen(method);
            if (method_len > max_method_len) {
                assert(top == lua_gettop(L));
                return luaL_error(L, "http.request does not support request methods longer than %d characters.", max_method_len);
            }

            // The callback is called from CompScriptOnMessage in comp_script.cpp
            luaL_checktype(L, 3, LUA_TFUNCTION);
            lua_pushvalue(L, 3);
            // NOTE: By convention m_FunctionRef is offset by LUA_NOREF, in order to have 0 for "no function"
            int callback = dmScript::RefInInstance(L) - LUA_NOREF;

            char* headers = 0;
            int headers_length = 0;
            if (top > 3 && !lua_isnil(L, 4)) {
                dmArray<char> h;
                h.SetCapacity(4 * 1024);

                luaL_checktype(L, 4, LUA_TTABLE);
                lua_pushvalue(L, 4);
                lua_pushnil(L);
                while (lua_next(L, -2)) {
                    const char* attr = lua_tostring(L, -2);
                    const char* val = lua_tostring(L, -1);
                    if (attr && val) {
                        uint32_t left = h.Capacity() - h.Size();
                        uint32_t required = strlen(attr) + strlen(val) + 2;
                        if (left < required) {
                            h.OffsetCapacity(dmMath::Max(required, 1024U));
                        }
                        h.PushArray(attr, strlen(attr));
                        h.Push(':');
                        h.PushArray(val, strlen(val));
                        h.Push('\n');
                    } else {
                        // luaL_error would be nice but that would evade call to 'h' destructor
                        dmLogWarning("Ignoring non-string data passed as http request header data");
                    }
                    lua_pop(L, 1);
                }