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2025-02-10Provide better control over which HTTP protocols are enabledLoïc Hoguin
Over cleartext TCP the `protocols` option lists the enabled protocols. The default is to allow both HTTP/1.1 and HTTP/2. Over TLS the default protocol to use when ALPN is not used can now be configured via the `alpn_default_protocol` option. Performing an HTTP/1.1 upgrade to HTTP/2 over TLS is now rejected with an error as connecting to HTTP/2 over TLS requires the use of ALPN (or that HTTP/2 be the default when connecting over TLS).
2025-02-10Clarify that reverse/format_error constraint ops are experimentalLoïc Hoguin
2025-02-07Deprecate the inactivity_timeout optionsLoïc Hoguin
When idle_timeout is configured we do not need a separate timer to detect inactivity. Disabling idle_timeout is not recommended and should not be necessary.
2025-02-07Add hibernate option to cowboy_http and cowboy_http2Loïc Hoguin
When enabled the connection process will automatically hibernate. Because hibernation triggers GC, this can be used as a way to keep memory usage lower, at the cost of performance.
2025-02-05Lower the lower dynamic buffer value to 1024Loïc Hoguin
There's not a big performance difference between 8192 and 1024 so let's use less memory at the start of the connection.
2025-02-05Implement dynamic socket buffer sizesLoïc Hoguin
Cowboy will set the socket's buffer size dynamically to better fit the current workload. When the incoming data is small, a low buffer size reduces the memory footprint and improves responsiveness and therefore performance. When the incoming data is large, such as large HTTP request bodies, a larger buffer size helps us avoid doing too many binary appends and related allocations. Setting a large buffer size for all use cases is sub-optimal because allocating more than needed necessarily results in a performance hit (not just increased memory usage). By default Cowboy starts with a buffer size of 8192 bytes. It then doubles or halves the buffer size depending on the size of the data it receives from the socket. It stops decreasing at 8192 and increasing at 131072 by default. To keep track of the size of the incoming data Cowboy maintains a moving average. It allows Cowboy to avoid changing the buffer too often but still react quickly when necessary. Cowboy will increase the buffer size when the moving average is above 90% of the current buffer size, and decrease when the moving average is below 40% of the current buffer size. The current buffer size and moving average are propagated when switching protocols. The dynamic buffer is implemented in HTTP/1, HTTP/2 and HTTP/1 Websocket. HTTP/2 Websocket has it disabled because it doesn't interact directly with the socket; in that case it is HTTP/2 that has a dynamic buffer. The dynamic buffer provides a very large performance improvement in many scenarios, at minimal cost for others. Because it largely depend on the underlying protocol the improvements are no all equal. TLS and compression also impact the results. The improvement when reading a large request body, with the requests repeated in a fast loop are: * HTTP: 6x to 20x faster * HTTPS: 2x to 6x faster * H2: 4x to 5x faster * H2C: 20x to 40x faster I am not sure why H2C's performance was so bad, especially compared to H2, when using default buffer sizes. Dynamic buffers make H2C a lot more viable with default settings. The performance impact on "hello world" type requests is minimal, it goes from -5% to +5% roughly. Websocket improvements vary again depending on the protocol, but also depending on whether compression is enabled: * HTTP echo: roughly 2x faster * HTTP send: roughly 4x faster * H2C echo: roughly 2x faster * H2C send: 3x to 4x faster In the echo test we reply back, and Gun doesn't have the dynamic buffer optimisation, so that probably explains the x2 difference. With compression however there isn't much improvement. The results are roughly within -10% to +10% of each other. Zlib compression seems to be a bottleneck, or at least to modify the performance profile to such an extent that the size of the buffer does not matter. This happens to randomly generated binary data as well so it is probably not caused by the test data.
2025-01-23Fix supported OTP version in user guideLoïc Hoguin
2025-01-16Websocket: Allow setting the max_frame_size option dynamicallyLoïc Hoguin
This can be used to limit the maximum frame size before some authentication or other validation is completed.
2024-03-14Cowboy 2.12.02.12.0Loïc Hoguin
2024-03-14Add max_fragmented_header_block_size HTTP/2 optionLoïc Hoguin
2024-01-25Refresh copyright linesLoïc Hoguin
2024-01-23Cowboy 2.11Loïc Hoguin
2024-01-23Document reset_idle_timeout_on_send optionLoïc Hoguin
2024-01-23Getting started must include relx in depsLoïc Hoguin
2024-01-23Update the guide with range requests supportLoïc Hoguin
Also update the list of headers cowboy_rest might set and tweak a small number of other items.
2024-01-22Document range requestsLoïc Hoguin
2024-01-17Add missing manual pages for cowboy_stream functionsLoïc Hoguin
2024-01-16REST: Allow generate_etag to return undefinedLoïc Hoguin
This allows conditionally generating an etag.
2024-01-16Recommend increasing max_frame_size_received HTTP/2 optionLoïc Hoguin
2024-01-08Document body reading in auto modeLoïc Hoguin
It is now tested both via cowboy_req:read_body and via cowboy_req:cast. Removes a bad example from the guide of body reading with period of infinity, which does not work.
2024-01-08Ensure HTTP/1.1 Websocket resets the trap_exit flagLoïc Hoguin
While we are identified as a supervisor in the tree, we no longer manage children processes at that point, so do not need to trap exit signals. Users can still enable trap_exit if they prefer to.
2024-01-08Always add vary: accept-encoding in cowboy_compress_hLoïc Hoguin
We must add it even if we don't end up compressing because it indicates that we might. This indication doesn't mean that the user agent's accept-encoding values will ever result in content encoding being applied.
2024-01-05Don't automatically compress when response has etagLoïc Hoguin
In the cowboy_compress_h stream handler. Otherwise this could cause issues with caching, with the etag being the same for compressed/uncompressed content. Users that wish to send etags AND compress will have to do it manually for the time being.
2024-01-05Add cowboy:get_env/2,3Loïc Hoguin
2024-01-04Rework and improve the decompress stream handlerLoïc Hoguin
The read buffer was changed into an iovec to avoid doing too many binary concatenations and allocations. Decompression happens transparently: when decoding gzip, the content-encoding header is removed (we only decode when "gzip" is the only encoding so nothing remains). We always add a content_decoded key to the Req object. This key contains a list of codings that were decoded, in the reverse order in which they were. Currently it can only be empty or contain <<"gzip">> but future improvements or user handlers may see it contain more values. The option to disable decompression was renamed to decompress_enabled and defaults to true. It is no longer possible to enable/disable decompression in the middle of reading the body: this ensures that the data we pass forward is always valid. Various smaller improvements were made to the code, tests and manual pages.
2023-12-21Add cowboy_decompress_h stream handlerjdamanalo
2023-12-15Add timeout to cowboy_loopjdamanalo
LH: I have added a test that does both hibernate and timeout and fixed a related issue. I also tweaked the docs and tests.
2023-12-12Handle socket errors in HTTP/1.1 and HTTP/2Loïc Hoguin
Doing so will let us notice when the connection is gone instead of waiting for timeouts, at least in the cases where the remote socket was closed properly. Timeouts are still needed in case of TCP half-open problems. This change means that the order of stream handler commands is more important than before because socket errors may occur during the processing of commands.
2023-12-07Fix position of rate_limited/2 callback in REST workflow guideLoïc Hoguin
2023-12-07Fix Websocket subprotocol exampleLoïc Hoguin
2023-12-06Fix typos in documentationKian-Meng, Ang
2023-12-06Add 'max_cancel_stream_rate' config for the rapid reset attackViktor Söderqvist
Co-authored-by: Björn Svensson <[email protected]>
2023-05-02Fix Ranch link in user guideLoïc Hoguin
2023-04-28Cowboy 2.10.02.10.0Loïc Hoguin
2021-05-12Cowboy 2.9.02.9.0Loïc Hoguin
2021-04-24Two more HTTP specsLoïc Hoguin
2020-11-27AcceptCallback may now return created/see_other tuples for POSTMartin Björklund
They replace and deprecate the {true,URI} return value.
2020-11-27Graceful shutdownViktor Söderqvist
Note: This commit makes cowboy depend on cowlib master. Graceful shutdown for HTTP/2: 1. A GOAWAY frame with the last stream id set to 2^31-1 is sent and a timer is started (goaway_initial_timeout, default 1000ms), to wait for any in-flight requests sent by the client, and the status is set to 'closing_initiated'. If the client responds with GOAWAY and closes the connection, we're done. 2. A second GOAWAY frame is sent with the actual last stream id and the status is set to 'closing'. If no streams exist, the connection terminates. Otherwise a second timer (goaway_complete_timeout, default 3000ms) is started, to wait for the streams to complete. New streams are not accepted when status is 'closing'. 3. If all streams haven't completed after the second timeout, the connection is forcefully terminated. Graceful shutdown for HTTP/1.x: 1. If a request is currently being handled, it is waited for and the response is sent back to the client with the header "Connection: close". Then, the connection is closed. 2. If the current request handler is not finished within the time configured in transport option 'shutdown' (default 5000ms), the connection process is killed by its supervisor (ranch). Implemented for HTTP/1.x and HTTP/2 in the following scenarios: * When receiving exit signal 'shutdown' from the supervisor (e.g. when cowboy:stop_listener/3 is called). * When a connection process is requested to terminate using sys:terminate/2,3. LH: Edited tests a bit and added todos for useful tests to add.
2020-08-19Minor grammar correctionsThomas Sciaroni
Verb agreement error "The request process executes middlewares which, by default, including the router and then the execution of handlers." -> "The request process executes middlewares. By default, the request process executes the router and then the handlers." Adverbial clause at beginning of sentence needs comma "By default Cowboy comes..." -> "By default, Cowboy comes..."
2020-07-01Tweak a sentence in the guideLoïc Hoguin
Thanks Tamir Halperin for pointing this out. [skip ci]
2020-05-28Fix the cowboy_req:inform/3 example in the manualLoïc Hoguin
2020-05-21Cowboy 2.8.0Loïc Hoguin
2020-05-20Increase the default max_keepalive HTTP option to 1000Loïc Hoguin
100 is very low for current deployments. 1000 is more appropriate as a default value.
2020-05-20Clarify the routing algorithmLoïc Hoguin
2020-04-08Document the HTTP/2 linger_timeout optionLoïc Hoguin
2020-04-08Clarify that protocol opts may be defined by stream handlersLoïc Hoguin
2020-03-30Add more headers to cowboy_req:parse_header/2,3Loïc Hoguin
2020-03-29Increase the default max_received_frame_rateLoïc Hoguin
Allow 10000 frames every 10 seconds instead of just 1000, as the limit was too quickly reached in some deployments.
2020-03-29Add more specificationsLoïc Hoguin
2020-02-08Add Trace Context to the list of specsLoïc Hoguin