Add thrift_base64_transport which writes base64 encoded data

Summary:
  This is to make it easy to run Hadoop mapreduces using Hadoop Streaming on thrift-serialized structs
  without implementing any special file splitter or anything

Test plan: test_disklog:t_base64()


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@666466 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/alterl/src/thrift_base64_transport.erl b/lib/alterl/src/thrift_base64_transport.erl
new file mode 100644
index 0000000..e521d11
--- /dev/null
+++ b/lib/alterl/src/thrift_base64_transport.erl
@@ -0,0 +1,45 @@
+-module(thrift_base64_transport).
+
+-behaviour(thrift_transport).
+
+%% API
+-export([new/1, new_transport_factory/1]).
+
+%% thrift_transport callbacks
+-export([write/2, read/2, flush/1, close/1]).
+
+%% State
+-record(b64_transport, {wrapped}).
+
+new(Wrapped) ->
+    State = #b64_transport{wrapped = Wrapped},
+    thrift_transport:new(?MODULE, State).
+
+
+write(#b64_transport{wrapped = Wrapped}, Data) ->
+    thrift_transport:write(Wrapped, base64:encode(iolist_to_binary(Data))).
+
+
+%% base64 doesn't support reading quite yet since it would involve
+%% nasty buffering and such
+read(#b64_transport{wrapped = Wrapped}, Data) ->
+    {error, no_reads_allowed}.
+
+
+flush(#b64_transport{wrapped = Wrapped}) ->
+    thrift_transport:write(Wrapped, <<"\n">>),
+    thrift_transport:flush(Wrapped).
+
+
+close(Me = #b64_transport{wrapped = Wrapped}) ->
+    flush(Me),
+    thrift_transport:close(Wrapped).
+
+
+%%%% FACTORY GENERATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+new_transport_factory(WrapFactory) ->
+    F = fun() ->
+                {ok, Wrapped} = WrapFactory(),
+                new(Wrapped)
+        end,
+    {ok, F}.
diff --git a/lib/alterl/src/thrift_buffered_transport.erl b/lib/alterl/src/thrift_buffered_transport.erl
index d71291d..a298cb1 100644
--- a/lib/alterl/src/thrift_buffered_transport.erl
+++ b/lib/alterl/src/thrift_buffered_transport.erl
@@ -11,7 +11,7 @@
 -behaviour(thrift_transport).
 
 %% API
--export([new/1]).
+-export([new/1, new_transport_factory/1]).
 
 %% gen_server callbacks
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
@@ -39,6 +39,8 @@
             Else
     end.
 
+
+
 %%--------------------------------------------------------------------
 %% Function: write(Transport, Data) -> ok
 %%
@@ -157,3 +159,10 @@
 %%--------------------------------------------------------------------
 %%% Internal functions
 %%--------------------------------------------------------------------
+%%%% FACTORY GENERATION %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+new_transport_factory(WrapFactory) ->
+    F = fun() ->
+                {ok, Wrapped} = WrapFactory(),
+                new(Wrapped)
+        end,
+    {ok, F}.
diff --git a/test/erl/src/test_disklog.erl b/test/erl/src/test_disklog.erl
index 78b792c..81b7b50 100644
--- a/test/erl/src/test_disklog.erl
+++ b/test/erl/src/test_disklog.erl
@@ -28,3 +28,35 @@
 
     ok.
 
+
+
+t_base64() ->
+    {ok, TransportFactory} =
+        thrift_disk_log_transport:new_transport_factory(
+          test_disklog,
+          [{file, "/tmp/test_b64_log"},
+           {size, {1024*1024, 10}}]),
+    {ok, B64Factory} =
+        thrift_base64_transport:new_transport_factory(TransportFactory),
+    {ok, BufFactory} =
+        thrift_buffered_transport:new_transport_factory(B64Factory),
+    {ok, ProtocolFactory} = thrift_binary_protocol:new_protocol_factory(
+                              BufFactory, []),
+    {ok, Client} = thrift_client:start_link(ProtocolFactory, thriftTest_thrift),
+
+    io:format("Client started~n"),
+
+    % We have to make async calls into this client only since otherwise it will try
+    % to read from the disklog and go boom.
+    {ok, ok} = thrift_client:call(Client, testAsync, [16#deadbeef]),
+    io:format("Call written~n"),
+
+    % Use the send_call method to write a non-async call into the log
+    ok = thrift_client:send_call(Client, testString, [<<"hello world">>]),
+    io:format("Non-async call sent~n"),
+
+    ok = thrift_client:close(Client),
+    io:format("Client closed~n"),
+
+    ok.
+