MySQL Server Protocol in Erlang. This project let you implement the MySQL protocol for your server. Throught a MySQL connection you could send queries or fake a MySQL connection to do a proxy or whatever else.
If you want to use, only add this in rebar.config:
{deps, [
{myproto, ".*", {git, "git://github.com/altenwald/myproto.git", master}}
]}.If you want configure the port, the handler and the server sign:
{myproto, [
{handler, my_dummy_handler},
{parse_query, true},
{server_sign, <<"5.5-myproto">>},
{port, 3306}
]}.This is a little tutorial to show you the use of this library. As a little introduction, you can create your environment as follow:
mkdir -p mydummy/apps/mydummy
cd mydummy/apps/mydummy
rebar create template=simpleapp appid=mydummy
cd ../..
mkdir rel
cd rel
rebar create template=simplenode nodeid=mydummy
cd ..Create the file rebar.config as follow:
{sub_dirs, ["apps/*", "rel"]}.
{deps, [
{myproto, ".*", {git, "git://github.com/altenwald/myproto.git", master}}
]}.Modify the file rel/files/sys.config as:
[
{myproto, [
{handler, mydummy},
{parse_query, true},
{server_sign, <<"5.5-myproto">>},
{port, 3306}
]},
%% SASL config
{sasl, [
{sasl_error_logger, {file, "log/sasl-error.log"}},
{errlog_type, error},
{error_logger_mf_dir, "log/sasl"}, % Log directory
{error_logger_mf_maxbytes, 10485760}, % 10 MB max file size
{error_logger_mf_maxfiles, 5} % 5 files max
]}
].Now, you can create the apps/mydummy/src/mydummy.erl module:
-module(mydummy).
-behaviour(gen_myproto).
-include_lib("myproto/include/myproto.hrl").
-export([check_pass/3, execute/2, terminate/2]).
-record(my, {
db
}).
check_pass(User, Hash, Password) ->
case my_request:check_clean_pass(User, Hash) of
HashedPassword -> {ok, HashedPassword, #my{}};
_ -> {error, <<"Password incorrect!">>}
end.
metadata(version, State) ->
{reply, <<"my cool server 1.0">>, State};
metadata({connect_db, Database}, State) ->
{noreply, State#my{db = Database}};
metadata(databases, State) ->
{reply, [<<"comet">>], State};
metadata(tables, #db{db = <<"storage">>} = State) ->
{reply, {<<"storage">>, [<<"channels">>, <<"users">>]}, State};
metadata({fields, <<"channels">> = Table}, #db{db = <<"storage">> = DB} = State) ->
{reply, {DB, Table, [{name,string},{users_count,integer},{started_at,integer}]}, State};
metadata(_, #my{} = State) ->
{noreply, State}.
execute(#request{info =
#select{params=[#variable{name = <<"version_comment">>}]
}}, State) ->
Info = {
[#column{name = <<"@@version_comment">>, type=?TYPE_VARCHAR, length=20}],
[[<<"myproto 0.1">>]]
},
{reply, #response{status=?STATUS_OK, info=Info}, State};
execute(#request{command = ?COM_QUIT}, State) ->
lager:info("Exiting~n", []),
{stop, normal, State};
execute(#request{info = #select{}} = Request, State) ->
lager:info("Request: ~p~n", [Request]),
Info = {
[
#column{name = <<"Info">>, type=?TYPE_VARCHAR, length=20},
#column{name = <<"Info2">>, type=?TYPE_VARCHAR, length=20}
],
[
[<<"Not implemented!">>, <<"Yet">>],
[<<"Testing MultiColumn!">>, <<"Still">>]
]
},
{reply, #response{status=?STATUS_OK, info=Info}, State};
execute(#request{} = Request, State) ->
lager:info("Unknown request: ~p", [Request]),
{reply, default, State}. % Return default reply if you don't know answer on this request
terminate(_Reason, _State) ->
ok.Please, mention that dummy module must implement metadata callback, because usually mysql clients ask a lot of information on start about databases, tables and fields in them.
For example, mysql has three different protocols for querying table structure. myproto hides this stuff from you in a very simple and convenient way.
Add this to rel/reltool.config:
{sys,
{lib_dirs, ["../apps", "../deps"]},
{erts, [{mod_cond, derived}, {app_file, strip}]},
{app_file, strip},
{rel, "mydummy", "1", [
kernel,
stdlib,
sasl,
inets,
lager,
myproto,
mydummy
]},
...Now time to build:
rebar get-deps compile generateAnd time to launch:
rel/mydummy/bin/mydummy consoleNow, to test, in another terminal or shell:
mysql -uroot -proot -h127.0.0.1You can use some SQL statements as:
SELECT @@version_comment;
SELECT * FROM sometable;Done :-)
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent