Simplify eetcd:open function with a single options parameter

These changes break the original API style, replace it with a simpler style: `eetcd:open(Name, Endopoints, Options)`.

README.md

@@ -296,17 +296,22 @@ Migration from eetcd 0.3.6 to 0.4.x
 eetcd 0.4.x now dependents on Gun 2.0, which introduced some breaking changes,
 and propagate to eetcd.
 
-The transport options are split into `tcp_opts` and `tls_opts`. As a result the
-functions `eetcd:open/4,5` have been replaced with `eetcd:open/5,6`.
+The prior transport options are split into `tcp_opts` and `tls_opts` and moved
+inside the new `eetcd:opts()` parameter. As a result, the functions `eetcd:open/4,5`
+have been replaced with `eetcd:open/2,3`.
 
 Likewise, the transport options for `eetcd_maintenance` APIs are split into
 `tcp_opts` and `tls_opts` as well.
 
-- The function `eetcd_maintenance:defragment/3` has been replaced with `eetcd_maintenance:defragment/4`.
-- The function `eetcd_maintenance:status/3` has been replaced with `eetcd_maintenance:status/4`.
-- The function `eetcd_maintenance:has_kv/4` has been replaced with `eetcd_maintenance:has_kv/5`.
+- The function `eetcd:open/4,5` has been replaced with `eetcd:open/3`.
+- The function `eetcd_maintenance:defragment/3` has been replaced with `eetcd_maintenance:defragment/2`.
+- The function `eetcd_maintenance:status/3` has been replaced with `eetcd_maintenance:status/2`.
+- The function `eetcd_maintenance:has_kv/4` has been replaced with `eetcd_maintenance:has_kv/3`.
 
 New options `{domain_lookup_timeout, Interval}` and `{tls_handshake_timeout, Interval}`
-have been added for `eetcd:open/5,6`. Alone with the prior `{connect_timeout, Interval}`,
+have been added for `eetcd:open/3`. Alone with the prior `{connect_timeout, Interval}`,
 it allows the underlining Gun library to get separate events when connecting,
 the domain lookup, connection and TLS handshakes.
+- `tls_opts` Passed to Gun.
+
+Read more details of Gun options in the [Gun 2.0 manual](https://ninenines.eu/docs/en/gun/2.0/manual/gun/).

src/eetcd.erl

@@ -1,33 +1,35 @@
 -module(eetcd).
 -include("eetcd.hrl").
 %% API
--export([open/2, open/5, open/6, close/1]).
+-export([open/2, open/3, close/1]).
 -export([info/0]).
 -export([new/1, with_timeout/2]).
 -export([get_prefix_range_end/1]).
+-export_type([opts/0]).
+
+-type opts() :: [ {mode, connect_all | random} |
+                  {transport, tcp | tls | ssl} |
+                  {name, string()} |
+                  {password, string()} |
+                  {auto_sync_interval_ms, non_neg_integer()} |
+                  {retry, non_neg_integer()} |
+                  {retry_timeout, pos_integer()} |
+                  {connect_timeout, timeout()} |
+                  {domain_lookup_timeout, timeout()} |
+                  {tls_handshake_timeout, timeout()} |
+                  {tcp_opts, [gen_tcp:connect_option()]} |
+                  {tls_opts, [ssl:tls_client_option()]}
+                ].
 
 %% @doc Connects to a etcd server on TCP port
 %% Port on the host with IP address Address, such as:
 %% `open(test,["127.0.0.1:2379","127.0.0.1:2479","127.0.0.1:2579"]).'
 -spec open(name(), [string()]) -> {ok, pid()} | {error, any()}.
 open(Name, Hosts) ->
-    open(Name, Hosts, [], tcp, [], []).
-
-%% @doc Connects to a etcd server.
--spec open(name(),
-    [string()],
-    tcp | tls | ssl,
-    [gen_tcp:connect_option()],
-    [ssl:tls_client_option()]) ->
-    {ok, pid()} | {error, any()}.
-open(Name, Hosts, Transport, TcpOpts, TlsOpts) when is_atom(Transport) ->
-    open(Name, Hosts, [], Transport, TcpOpts, TlsOpts).
+    open(Name, Hosts, [{transport, tcp}]).
 
 %% @doc Connects to a etcd server.
 %%
-%% @see `ssl:tls_client_option()' see all tls client options in `ssl' module.
-%% such as [{certfile, Certfile}, {keyfile, Keyfile}] or [{cert, Cert}, {key, Key}].
-%%
 %% Default mode is `connect_all', it creates multiple sub-connections (one sub-connection per each endpoint).
 %% The balancing policy is round robin.
 %% For instance, in 5-node cluster, `connect_all' would require 5 TCP connections,
@@ -55,26 +57,22 @@ open(Name, Hosts, Transport, TcpOpts, TlsOpts) when is_atom(Transport) ->
 %%
 %% `[{name, string()}, {password, string()}]' generates an authentication token based on a given user name and password.
 %%
+%% `{tcp_opts, [gen_tcp:connect_option()]}' and `{tls_opts, [ssl:tls_client_option()]}' are the
+%% options for gun:open/3 in Gun 2.0.
+%%
+%% See all TCP options in {@link gen_tcp} module.
+%%
+%% See all TLS client options in {@link ssl} module,
+%% such as `[{certfile, Certfile}, {keyfile, Keyfile}] or [{cert, Cert}, {key, Key}]'.
+%%
+%% Read more details of gun options in the
+%% [https://ninenines.eu/docs/en/gun/2.0/manual/gun/ Gun 2.0 manual].
+%%
 %% You can use `eetcd:info/0' to see the internal connection status.
--spec open(name(),
-    [string()],
-    [
-      {mode, connect_all | random}
-      | {name, string()}
-      | {password, string()}
-      | {retry, non_neg_integer()}
-      | {retry_timeout, pos_integer()}
-      | {connect_timeout, timeout()}
-      | {domain_lookup_timeout, timeout()}
-      | {tls_handshake_timeout, timeout()}
-    ],
-    tcp | tls | ssl,
-    [gen_tcp:connect_option()],
-    [ssl:tls_client_option()]) ->
-    {ok, pid()} | {error, any()}.
-open(Name, Hosts, Options, Transport, TcpOpts, TlsOpts) ->
+-spec open(name(), [string()], opts()) -> {ok, pid()} | {error, any()}.
+open(Name, Hosts, Options) ->
     Cluster = [begin [IP, Port] = string:tokens(Host, ":"), {IP, list_to_integer(Port)} end || Host <- Hosts],
-    eetcd_conn_sup:start_child([{Name, Cluster, Options, Transport, TcpOpts, TlsOpts}]).
+    eetcd_conn_sup:start_child([{Name, Cluster, Options}]).
 
 %% @doc close connections with etcd server.
 -spec close(name()) -> ok | {error, eetcd_conn_unavailable}.

src/eetcd_conn.erl

@@ -89,7 +89,7 @@ flush_token(Gun, Headers) ->
 %%%===================================================================
 %%% gen_statem callbacks
 %%%===================================================================
-init({Name, Hosts, Options, Transport, TcpOpts, TlsOpts}) ->
+init({Name, Hosts, Options}) ->
     erlang:process_flag(trap_exit, true),
     GunOpts = #{protocols => [http2],
         connect_timeout => proplists:get_value(connect_timeout, Options, 1000),
@@ -98,9 +98,9 @@ init({Name, Hosts, Options, Transport, TcpOpts, TlsOpts}) ->
         http2_opts => #{keepalive => 45000},
         retry => proplists:get_value(retry, Options, 0),
         retry_timeout => proplists:get_value(retry_timeout, Options, 5000),
-        transport => Transport,
-        tcp_opts => TcpOpts,
-        tls_opts => TlsOpts
+        transport => proplists:get_value(transport, Options, tcp),
+        tcp_opts => proplists:get_value(tcp_opts, Options, []),
+        tls_opts => proplists:get_value(tls_opts, Options, [])
     },
     AutoSyncInterval = proplists:get_value(auto_sync_interval_ms, Options, 0),
     Data0 = #{

src/eetcd_maintenance.erl

@@ -2,7 +2,7 @@
 -include("eetcd.hrl").
 %% API
 -export([alarm_list/1, alarm_disarm/3, alarm_disarm_all/1]).
--export([defragment/4, status/4, hash_kv/5, move_leader/2]).
+-export([defragment/2, status/2, hash_kv/3, move_leader/2]).
 
 %%% @doc AlarmList gets all active alarms.
 -spec alarm_list(name()|context()) ->
@@ -46,30 +46,30 @@ alarm_disarm_all(ConnName) ->
 %%% Defragment is an expensive operation. User should avoid defragmenting multiple members at the same time.
 %%% To defragment multiple members in the cluster, user need to call defragment multiple
 %%% times with different endpoints.
--spec defragment(iodata(), tcp | tls | ssl, [gen_tcp:connect_option()], [ssl:tls_client_option()]) ->
+-spec defragment(iodata(), eetcd:opts()) ->
     {ok,router_pb:'Etcd.DefragmentResponse'()}|{error,eetcd_error()}.
-defragment(Endpoint, Transport, TcpOpts, TlsOpts) ->
+defragment(Endpoint, Options) ->
     Fun = fun(Conn) -> eetcd_maintenance_gen:defragment(eetcd:new(Conn)) end,
-    dial(Endpoint, Transport, TcpOpts, TlsOpts, Fun).
+    dial(Endpoint, Options, Fun).
 
 %%% @doc Status gets the status of the endpoint.
--spec status(iodata(), tcp | tls | ssl, [gen_tcp:connect_option()], [ssl:tls_client_option()]) ->
+-spec status(iodata(), eetcd:opts()) ->
     {ok,router_pb:'Etcd.StatusResponse'()}|{error,eetcd_error()}.
-status(Endpoint, Transport, TcpOpts, TlsOpts) ->
+status(Endpoint, Options) ->
     Fun = fun(Conn) -> eetcd_maintenance_gen:status(eetcd:new(Conn)) end,
-    dial(Endpoint, Transport, TcpOpts, TlsOpts, Fun).
+    dial(Endpoint, Options, Fun).
 
 %%% @doc HashKV returns a hash of the KV state at the time of the RPC.
 %%% If revision is zero, the hash is computed on all keys. If the revision
 %%% is non-zero, the hash is computed on all keys at or below the given revision.
--spec hash_kv(iodata(), tcp | tls | ssl, [gen_tcp:connect_option()], [ssl:tls_client_option()], pos_integer()) ->
+-spec hash_kv(iodata(), eetcd:opts(), pos_integer()) ->
     {ok,router_pb:'Etcd.HashKVResponse'()}|{error,eetcd_error()}.
-hash_kv(Endpoint, Transport, TcpOpts, TlsOpts, Rev) ->
+hash_kv(Endpoint, Options, Rev) ->
     Fun = fun(Conn) ->
         Context = maps:put(revision, Rev, eetcd:new(Conn)),
         eetcd_maintenance_gen:hash_kv(Context)
           end,
-    dial(Endpoint, Transport, TcpOpts, TlsOpts, Fun).
+    dial(Endpoint, Options, Fun).
 
 %%% Snapshot provides a reader for a point-in-time snapshot of etcd.
 %%% If the context "ctx" is canceled or timed out, reading from returned
@@ -89,10 +89,10 @@ move_leader(Context, TargetID) ->
 %%%===================================================================
 %%% Internal functions
 %%%===================================================================
-dial(Endpoint, Transport, TcpOpts, TlsOpts, Fun) ->
+dial(Endpoint, Options, Fun) ->
     Conn = make_ref(),
     try
-        case eetcd:open(Conn, [Endpoint], Transport, TcpOpts, TlsOpts) of
+        case eetcd:open(Conn, [Endpoint], Options) of
             {ok, _Pid} -> Fun(Conn);
             Err ->
                 Err

test/eetcd_lease_SUITE.erl

@@ -19,7 +19,7 @@ groups() ->
 init_per_suite(Config) ->
     application:ensure_all_started(eetcd),
     {ok, _Pid} = eetcd:open(?Name, ["127.0.0.1:2379", "127.0.0.1:2479", "127.0.0.1:2579"],
-                            [{mode, random}], tcp, [], []),
+                            [{mode, random}, {transport, tcp}]),
     Config.
 
 init_per_testcase(_TestCase, Config) ->

test/eetcd_lock_SUITE.erl

@@ -27,7 +27,7 @@ groups() ->
 init_per_suite(Config) ->
     application:ensure_all_started(eetcd),
     {ok, _Pid} = eetcd:open(?Name, ["127.0.0.1:2379", "127.0.0.1:2479", "127.0.0.1:2579"],
-                            [{mode, random}], tcp, [], []),
+                            [{mode, random}, {transport, tcp}]),
     Config.
 
 init_per_testcase(_TestCase, Config) ->

test/eetcd_maintenance_SUITE.erl

@@ -33,9 +33,9 @@ end_per_suite(Config) ->
 %%%===================================================================
 
 smoke_test(_Config) ->
-    {ok, _} = eetcd_maintenance:defragment(?Endpoint, tcp, [], []),
-    {ok, _} = eetcd_maintenance:status(?Endpoint, tcp, [], []),
-    {ok, _} = eetcd_maintenance:hash_kv(?Endpoint, tcp, [], [], 0),
+    {ok, _} = eetcd_maintenance:defragment(?Endpoint, [{transport, tcp}]),
+    {ok, _} = eetcd_maintenance:status(?Endpoint, [{transport, tcp}]),
+    {ok, _} = eetcd_maintenance:hash_kv(?Endpoint, [{transport, tcp}], 0),
     ok.
 
 %%%===================================================================