Mint adapter cannot upload more than 65535 bytes on HTTP/2 #394
Description
- tesla 1.3.3
- mint 1.1.0
To reproduce,
client = Tesla.client([], Tesla.Adapter.Mint)
Tesla.post(client, "https://httpbin.org/post", String.duplicate("0", 65536))returns :exceeds_window_size error.
%Mint.HTTPError{
module: Mint.HTTP2,
reason: {:exceeds_window_size, :connection, 65535}
}Full error
{:error,
%Mint.HTTP2{
buffer: <<0, 0, 4, 8, 0, 0, 0, 0, 0, 127, 255, 0, 0>>,
client_settings: %{
enable_push: true,
max_concurrent_streams: 100,
max_frame_size: 16384
},
client_settings_queue: {[[]], []},
decode_table: %Mint.HTTP2.HPACK.Table{
entries: [],
length: 0,
max_table_size: 4096,
size: 0
},
encode_table: %Mint.HTTP2.HPACK.Table{
entries: [],
length: 0,
max_table_size: 4096,
size: 0
},
headers_being_processed: nil,
hostname: "httpbin.org",
mode: :active,
next_stream_id: 5,
open_client_stream_count: 1,
open_server_stream_count: 0,
ping_queue: {[], []},
port: 443,
private: %{},
ref_to_stream_id: %{#Reference<0.4203460067.3989045250.44202> => 3},
scheme: "https",
server_settings: %{
enable_push: true,
initial_window_size: 65536,
max_concurrent_streams: 128,
max_frame_size: 16777215,
max_header_list_size: :infinity
},
socket: {:sslsocket, {:gen_tcp, #Port<0.2811>, :tls_connection, :undefined},
[#PID<0.1699.0>, #PID<0.1698.0>]},
state: :open,
streams: %{
3 => %{
id: 3,
received_first_headers?: false,
ref: #Reference<0.4203460067.3989045250.44202>,
state: :open,
window_size: 65536
}
},
transport: Mint.Core.Transport.SSL,
window_size: 65535
},
%Mint.HTTPError{
module: Mint.HTTP2,
reason: {:exceeds_window_size, :connection, 65535}
}}That is because window_size: 65535 is set initially, according to standard, but is not updated when the server sends WINDOW_UPDATE frames.
Each time Tesla sends data using Mint.HTTP.stream_request_body, the window size is decremented by data’s size. When the window size gets low, the server sends WINDOW_UPDATE frames to increment the connection’s window size. Calling Mint.HTTP.stream to read responses will automatically do this.
However, the adapter repeatedly calls Mint.HTTP.stream_request_body without calling Mint.HTTP.stream so the window size hits zero and Mint errors.