httpc: allow streaming of PUT and POST request bodies

This is a must when uploading large bodies that are to large to store
in a string or binary.

Besides a string or binary, a body can now be a function and
an accumulator.

Example:

-module(httpc_post_stream_test).
-compile(export_all).

-define(LEN, 1024 * 1024).

prepare_data() ->
    {ok, Fd} = file:open("test_data.dat", [binary, write]),
    ok = file:write(Fd, lists:duplicate(?LEN, "1")),
    ok = file:close(Fd).

test() ->
    inets:start(),
    ok = prepare_data(),
    {ok, Fd1} = file:open("test_data.dat", [binary, read]),
    BodyFun = fun(Fd) ->
        case file:read(Fd, 512) of
        eof ->
            eof;
        {ok, Data} ->
            {ok, Data, Fd}
        end
    end,
    {ok, {{_,200,_}, _, _}} = httpc:request(post, {"http://localhost:8888",
        [{"content-length", integer_to_list(?LEN)}], "text/plain", {BodyFun, Fd1}}, [], []),
    ok = file:close(Fd1).

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/inets/src/http_client/httpc.erl b/lib/inets/src/http_client/httpc.erl
index 851364001c..b82a9db4c9 100644
--- a/lib/inets/src/http_client/httpc.erl
+++ b/lib/inets/src/http_client/httpc.erl
@@ -126,7 +126,9 @@ request(Url, Profile) ->
 %%      Header = {Field, Value}
 %%	Field = string()
 %%	Value = string()
-%%	Body = string() | binary() - HTLM-code
+%%	Body = string() | binary() | {fun(SendAcc) -> SendFunResult, SendAcc} - HTLM-code
+%%      SendFunResult = eof | {ok, iolist(), NewSendAcc}
+%%      SendAcc = NewSendAcc = term()
 %%
 %% Description: Sends a HTTP-request. The function can be both
 %% syncronus and asynchronous in the later case the function will