Merge branch 'peterdmv/inets/httpc-content-length/ERL-733/OTP-15338' into maint

* peterdmv/inets/httpc-content-length/ERL-733/OTP-15338:
  inets: Fix handling of 'Content-Length' (httpc)

Change-Id: I3281949d47d2494dc8d6f3af3e93b46cdbbc24b9

1 files changed, 10 insertions, 1 deletions

diff --git a/lib/inets/src/http_client/httpc_request.erl b/lib/inets/src/http_client/httpc_request.erl
index 9b81bd7a80..9db961cf9e 100644
--- a/lib/inets/src/http_client/httpc_request.erl
+++ b/lib/inets/src/http_client/httpc_request.erl
@@ -221,7 +221,8 @@ update_headers(Headers, ContentType, Body, []) ->
             %% that does not include a message body. This implies that either the
             %% Content-Length or the Transfer-Encoding header MUST be present.
             %% DO NOT send content-type when Body is empty.
-            Headers#http_request_h{'content-type' = ContentType};
+            Headers1 = Headers#http_request_h{'content-type' = ContentType},
+            handle_transfer_encoding(Headers1);
         _ ->
             Headers#http_request_h{
               'content-length' = body_length(Body),
@@ -230,6 +231,14 @@ update_headers(Headers, ContentType, Body, []) ->
 update_headers(_, _, _, HeadersAsIs) ->
     HeadersAsIs.
 
+handle_transfer_encoding(Headers = #http_request_h{'transfer-encoding' = undefined}) ->
+    Headers;
+handle_transfer_encoding(Headers) ->
+    %% RFC7230 3.3.2
+    %% A sender MUST NOT send a 'Content-Length' header field in any message
+    %% that contains a 'Transfer-Encoding' header field.
+    Headers#http_request_h{'content-length' = undefined}.
+
 body_length(Body) when is_binary(Body) ->
    integer_to_list(size(Body));