Articles

Cowboy 2.6

2018 19 Nov

Cowboy 2.6.0 has been released! Cowboy 2.6 greatly refactored the HTTP/2 code, a large part of which was moved to Cowlib and is now used by both the Cowboy server and the Gun client. A large number of tickets were also closed which resulted in many bugs fixed and many features and options added, although some of them are still experimental. Of note is the support for the PROXY protocol header built directly into Cowboy; the ability to use the sendfile tuple to send files while streaming a response body (for example you could build a tar file on the fly); and experimental support for range requests in the REST and static file handlers, including an automatic mode that lets you enable byte range requests to existing handlers with what's basically a one-liner.

Ranch 1.7

2018 14 Nov

Ranch 1.7.0 has been released! This release adds built-in support for the PROXY protocol. The PROXY protocol is a simple and efficient way for proxies to transmit information about the client. While a third-party library already existed, it was not entirely compatible with the Ranch interface, in particular when socket active mode was involved. This new implementation fixes that and supports the full protocol with as little overhead as possible compared to normal operations: just one extra function call.

Cowboy 2.5

2018 03 Oct

Cowboy 2.5.0 has been released! Cowboy 2.5 focused on making the test suites pass. It is now possible to get all the Cowboy tests to pass successfully, at least on Linux and on the more recent Erlang/OTP versions. HTTP/1.1 has been improved with a fix for the TCP reset problem and the ability to stream a response body without using chunked transfer-encoding. Two functions have been added: cowboy_req:stream_events/3 encodes and streams one or more text/event-stream events, and cowboy_req:read_and_match_urlencoded_body/2,3 reads, parses and matches application/x-www-form-urlencoded request bodies.

Gun 1.3

2018 01 Oct

Gun 1.3.0 has been released! Gun is an HTTP/1.1, HTTP/2 and Websocket client for Erlang/OTP. This release improves the CONNECT support introduced in the previous version and adds built-in Websocket protocol negotiation. A complete list of changes can be found in the migration guide: Migrating from Gun 1.2 to 1.3. You can donate to this project via GitHub Sponsors. These funds are used to pay for additional servers for testing. And healthy food.

Gun 1.2

2018 17 Sep

Gun 1.2.0 has been released! Gun is an HTTP/1.1, HTTP/2 and Websocket client for Erlang/OTP. Gun now supports issuing CONNECT requests to HTTP proxies in order to establish tunnels to origin servers. Gun can establish tunnels over one or more proxies as necessary. All existing protocols can be used inside the tunnel, including HTTP/1.1, HTTP/2 and Websocket over both TCP and TLS connections. Note that it is currently not possible to tunnel a TLS connection via an HTTPS proxy due to limitations in the current version of Erlang/OTP.

Ranch 1.6

2018 01 Aug

Ranch 1.6.0 has been released! This release sees the introduction of a suspend/resume mechanism for the listeners which makes the listener close the listening socket and stop accepting new connections. Existing connections continue uninterrupted. This can be used to update the socket options of the listener, or to implement a graceful shutdown. To that end a function has also been added which allows waiting until connections reach a certain number.

Gun 1.0

2018 27 Jul

Gun 1.0.0 has been released! Gun is an HTTP/1.1, HTTP/2 and Websocket client for Erlang/OTP. Gun provides an asynchronous interface and will keep the connection open to the server, reconnecting as necessary. Gun has existed for many years as the test client for Cowboy and is now mature enough to receive a proper version. Gun is battle tested by customers and other users but is not the most well tested client there is.

Asciideck: Asciidoc for Erlang

2018 13 Jun

Asciideck is a new project I have been working on in my spare time that implements an Asciidoc parser and translation of Asciidoc documents into various output formats. The Asciideck parser returns an AST for the document. That AST can be further manipulated should it be necessary: for example you may need to rewrite some relative links if you are not keeping the same file directory structure as the original Asciidoc documents.

Gun 1.0 release candidate 1

2018 04 Jun

Gun 1.0.0-rc.1 has been released! Gun is an HTTP/1.1, HTTP/2 and Websocket client for Erlang/OTP. Gun provides an asynchronous interface and will keep the connection open to the server, reconnecting as necessary. Gun has existed for many years as the test client for Cowboy and is now mature enough to receive a proper version. Gun is battle tested by customers and other users but is not the most well tested client there is.

Cowboy 2.4

2018 02 May

Cowboy 2.4.0 has been released! Numerous HTTP/2 options have been added to control the HTTP/2 SETTINGS and general behavior of HTTP/2 connections. The options for initial window sizes, maximum frame sizes or compression table sizes might be of interest for optimizing the performance of HTTP/2 connections. Experimental support for Websocket over HTTP/2 was added. Note that browsers do not currently support it. The only browser with partial support is Google Chrome 67 (dev build) started with a specific flag.

Cowboy 2.3

2018 04 Apr

Cowboy 2.3.0 has been released! This release focused on adding support for the functions from the sys module for introspecting Cowboy processes. Many bugs have also been fixed. A more complete list of changes can be found in the migration guide: Migrating from Cowboy 2.2 to 2.3. You can donate to this project via GitHub Sponsors because I need to eat snacks when I write code. Thanks in advance! As usual, feedback is appreciated, and issues should be reported by opening a ticket.

Cowboy 2.2

2017 13 Dec

Cowboy 2.2.0 has been released! This release focused on adding features required for writing gRPC servers and on completing test suites for the core HTTP RFCs. The cowboy_req:stream_trailers/2 function has been added. It terminates the streamed response by adding some trailer field values. This feature is required for gRPC. The max_skip_body_length option was added. It controls how much of the request body we are willing to skip to get to the next request for HTTP/1.

Cowboy 2.1

2017 09 Nov

Cowboy 2.1.0 has been released! This release focused on adding features that were temporarily removed during the 2.0 release process: The client TLS certificate can now be obtained. The 100 Continue response is now sent automatically again when necessary. NEW: It is now possible to send informational responses (1XX) directly from user code via the cowboy_req:inform/2,3 functions. NEW: cowboy_rest handlers can now switch to any other type of handler from almost any callback.

Cowboy 2.0

2017 04 Oct

Cowboy 2.0.0 has been released! This is the new stable version of Cowboy. There are no new releases planned for the 1.x version of Cowboy. The highlights from the release are: HTTP/2 support! Websocket compression! Much simpler, cleaner interface. No more weird errors just because you discard the Req object. A new low-level interface that receives all events from every set of request and response. This replaces the awkward hooks from 1.

Cowboy 2.0 release candidate 2

2017 23 Aug

Cowboy 2.0.0-rc.2 has been released! This is the new recommended version of Cowboy. Its API should not change before release. While you probably should not use it in production yet, many do successfully. Use at your own risk. This new version contains fixes for the following issues: HTTP/2 server push was using the wrong header compression context. HTTP/2 flow control could end up queueing data in the wrong order when resuming the sending of data.

Cowboy 2.0 release candidate 1

2017 24 Jul

Cowboy 2.0.0-rc.1 has been released! This is the new recommended version of Cowboy. Its API should not change before release. While you probably should not use it in production yet, many do successfully. Use at your own risk. The plan is to have a new RC version every couple weeks until the summer ends or later if there are still blocking issues open. Only issues that can't be fixed without making breaking changes to the interface may block the release.

The elephant in the room

2017 26 Mar

Have you ever tried telling someone why they should use Erlang? You boast the smaller code size, the auto healing mechanisms, the distribution and they seem really excited. They wonder why they never heard about Erlang before. And then you show them what the code looks like. All excitement goes away. The smiles disappear. Their face starts becoming really serious. You lost them. You know you lost them. They comment on the syntax, or perhaps you do, already admitting defeat.

Don't let it crash

2017 22 Jan

We have a specific mindset when writing Erlang programs. We focus on the normal execution of the program and don't handle most of the errors that may occur. We sometimes call this normal execution the happy path. The general pattern behind writing only for the happy path, letting the VM catch errors (writing them to a log for future consumption) and then having a supervisor restart the processes that failed from a clean state, has a name.

Cowboy 2.0 pre-release 4

2017 03 Jan

Cowboy 2.0.0-pre.4 has been released! This is the new recommended version of Cowboy. While I would not recommend putting it in production just yet, I do recommend you start writing new applications with this Cowboy version. The most significant changes in the pre-release are: A new architecture: there now is one process per connection and one process per request. This was done because HTTP/2 allows running requests concurrently. Stream handlers.

Ranch 1.3

2016 28 Nov

Ranch 1.3.0 has been released! This release fixes a number of long standing issues and adds a small number of features: The ssl application has been added to the list of dependencies. If you don't need it, you can remove it automatically when fetching Ranch or when building the release. If you do need it, you will no longer have issues shutting down a node because of Ranch. The ranch:info/0 and ranch:procs/2 can be used to retrieve information about Ranch's state.