formspec.lua

-- handler for credentials 
credentials_event = function(player, formname, fields)
    if formname == "core:google_credentials" then
        if fields.quit then return end
        if fields.send then
            minetest.show_formspec(player_name, "core:none",
                table.concat({"formspec_version[4]", "size[8,1,false]", "hypertext[0, 0.2; 8, 1;; <bigger><center>Credentials sending . . .<center><bigger>]"}, ""))
            local player_name = player:get_player_name()
            local conn = connections:get_connection(player_name, fields.service_addr, true)
            local content = table.concat({fields.key, fields.project, fields.zone}, " ")
            pcall(np_prot.file_write, conn.conn, "gcloud", content)
            minetest.show_formspec(player_name, "core:none",
                                   table.concat({"formspec_version[4]", "size[8,1,false]", "hypertext[0, 0.2; 8, 1;; <bigger><center>Credentials sent. Check registry<center><bigger>]"}, ""))
            minetest.after(3, function() minetest.show_formspec(player_name, "core:none", "") end)
        end
    end
end

-- registrer handler for credentials form
register.add_form_handler("core:google_credentials", credentials_event)

minetest.show_formspec(player_name, "core:google_credentials",
                       table.concat({"formspec_version[4]", "size[8,6,false]", "field[0,0;0,0;service_addr;;", minetest.formspec_escape(res), "]",
    "hypertext[0, 0.3; 8, 1;; <bigger><center>Google Cloud<center><bigger>]", "pwdfield[0.5, 1.5; 7, 0.7;key;key (in base64)]", "pwdfield[0.5, 2.6; 7, 0.7;project;project name]",
    "pwdfield[0.5, 3.7; 7, 0.7;zone;zone]", "button[5,4.8;2.5,0.7;send;send]"}, ""))