[ANN] httpx 0.11.0 released

httpx 0.11.0 has been released.

HTTPX.get("https://gitlab.com/honeyryderchuck/httpx
<https://gitlab.com/honeyryderchuck/httpx>")

HTTPX is an HTTP client library for the Ruby programming language.

Among its features, it supports:

* HTTP/2 and HTTP/1.x protocol versions
* Concurrent requests by default
* Simple and chainable API
* Proxy Support (HTTP(S), Socks4/4a/5)
* Simple Timeout System
* Lightweight by default (require what you need)

And also:

* Compression (gzip, deflate, brotli)
* Streaming Requests
* Authentication (Basic Auth, Digest Auth)
* Expect 100-continue
* Multipart Requests
* Cookies
* HTTP/2 Server Push
* H2C Upgrade
* Automatic follow redirects
* International Domain Names

These are the announcements since the last update:

## Features

### Webmock Adapter

`httpx` can now be integrated with `webmock`, a popular HTTP requests
stubbing library.

# minitest
require "webmock/minitest"
require "httpx/adapters/webmock"

# in rspec
require "webmock/rspec"
require "httpx/adapters/webmock"

# and now you're free for mocking
WebMock.enable!
stub_http_request(:get, "https://www.google.com").and_return(status: 200,
body: "here's google")

Read more about it in the [webmock integration documentation](
https://honeyryderchuck.gitlab.io/httpx/wiki/Webmock-Adapter).

### Datadog Adapter

`httpx` ships with integration for [ddtrace, datadog's official tracing
client](https://github.com/DataDog/dd-trace-rb). You just need to
initialize it the following way:

require "ddtrace"
require "httpx/adapters/datadog"

Datadog.configure do |c|
  c.use :httpx
end

A trace will be emitted for every request, so this should be an interesting
visualization if concurrent requests are sent.

Customization options and traces are similar to what [the net-http adapter
provides](
https://docs.datadoghq.com/tracing/setup_overview/setup/ruby/#nethttp).

Read more about it in the [datadog integration documentation](
https://honeyryderchuck.gitlab.io/httpx/wiki/Datadog-Adapter).

## Improvements

### Own multipart request encoder

`httpx` now ships with its own multipart formdata encoder, and does not
rely on `http-form_data` anymore:

HTTPX.plugin(:multipart).post(uri, form: {file: File.new("path/to/file")})

Read more about it in the [multipart plugin documentation](
https://honeyryderchuck.gitlab.io/httpx/wiki/Multipart-Uploads), including
also about why this was made.

### Expect Plugin

The `:expect` plugin now works reliably when the server does not support
the `expect: 100-continue` header, i.e. it'll upload the body after a
certain timeout. Building onn that, two behaviours are now implemented:

* A cache of domains which did not respond to the `expect` header is now
kept, so that subsequent requests can skip the timeout and immediately
upload the payload.
* If the "100 Continue" response arrives **after** the timeout expired and
the body has been uploaded, the domain is removed from the cache, and
subsequent requests will send the `expect` header.

### SNI/Host options

Some extension of the API was applied in order to support custom TLS
negotiation parameters. You can now pass `:hostname` under the `:ssl`
options, and this will be used for the SNI part of the TLS negotiation.
This is useful in scenarios where a proxy certificate doesn't apply for the
host one wants to send the request to:

response = session.get(proxy_ip, headers: { "host" => upstream_hostname },
ssl: { hostname: sni_hostname }

## Bugfixes

A default 5 second timeout is in-place when using the DNS `:system`
resolver, as it was found out that, when using the `resolv` library, the
DNS query will not be retried otherwise. You can change this setting py
passing `resolver_options: { timeouts: ANOTHER_TIMEOUT}`. In the future,
this may become another timeout option.