v2.0.0

This is the biggest release since v1.0.0. ttfb now supports HTTP/2 and
HTTP/3 (over QUIC) in addition to HTTP/1.1, and by default selects the newest
protocol the server supports.

• Library users: the ttfb() function is replaced by TtfbClient and
  TtfbOptions, and several types changed. See the BREAKING entries below.
• Binary users: the default protocol is no longer HTTP/1.1. Use --http1.1
  for the previous behavior. New options include --repeat for statistics,
  --json for scripts, --headers, --timeout, and -4/-6.

ttfb lib

• BREAKING The ttfb() function is replaced by TtfbClient, which is
  configured with TtfbOptions:
  TtfbClient::new(TtfbOptions::default()).measure(url).
  TtfbOptions::protocol takes a ProtocolSelection, and
  TtfbOutcome::protocol_selection() reports it. TtfbOptions is
  #[non_exhaustive], so that new options are no breaking change: set its
  fields on TtfbOptions::default().
• BREAKING TtfbError, ResolveDnsError, and InvalidUrlError are
  #[non_exhaustive].
• BREAKING TtfbError::CantConnectTls and TtfbError::CantVerifyTls
  are replaced by TtfbError::Tls, which describes the error as a string.
  The lib no longer depends on rustls-connector.
• BREAKING AllowInvalidCertsVerifier is no longer public. It was
  exported by accident.
• BREAKING InvalidUrlError::Other is removed. It was never used.
• BREAKING DurationPair no longer implements Default. A pair of zero
  durations isn't a meaningful measurement.
• BREAKING TtfbOutcome::tcp_connect_duration() and
  TtfbOutcome::tls_handshake_duration() are replaced by
  TtfbOutcome::connection_handshake(). It reports how the connection was
  established as the new ConnectionHandshake: a TCP connect with an optional
  TLS handshake, or a QUIC handshake for HTTP/3.
• BREAKING TtfbError has the new variants UnsupportedHttpProtocol,
  Http2, and Http3.
• BREAKING ResolveDnsError::Other and TtfbError::CantConfigureDNSError
  describe the error as a string instead of exposing the ResolveError of
  hickory-resolver, so that the DNS resolver can change without a breaking
  change.
• TLS trusts the system's root certificates and the bundled Mozilla root
  certificates together. Previously, the bundled ones were only used if the
  system's could not be loaded.
• HTTPS works with IPv6 addresses, such as https://[2606:4700:4700::1111].
• TtfbError compares CantConnectHttp and OtherStreamError correctly.
  Before, two errors of the same variant were never equal, while the two
  variants were equal with the same io::ErrorKind.
• The duration of the DNS lookup no longer includes starting the internal Tokio
  runtime and its thread, which took about 0.1-0.3 ms.
• Added TtfbOutcome::protocol(), which reports the HTTP protocol used as
  HttpProtocol.
• Added HTTP/2 measurements over TLS with HttpProtocol::Http2. They need
  the Cargo feature http2, which is enabled by default. Without it, they
  fail with the new TtfbError::UnsupportedHttpProtocol.
• Added HTTP/3 measurements over QUIC with HttpProtocol::Http3. They need
  the Cargo feature http3, which is enabled by default.
• ProtocolSelection::Auto, the default, selects HTTP/3, HTTP/2, or
  HTTP/1.1, whichever the server supports first in this order. Protocols built
  without their Cargo feature are skipped.
• TtfbOptions::ip_version selects the IP version of the connection:
  IpVersion::Any, the default, prefers IPv4 as before, while IpVersion::V4
  and IpVersion::V6 use only that version. A host without an address of that
  version fails with the new TtfbError::NoAddressForIpVersion.
• TtfbOptions::timeout limits the duration of a measurement, from the DNS
  lookup to the end of the download. It defaults to 10 s and must be between
  1 s and 60 min. A measurement that exceeds it fails with the new
  TtfbError::Timeout.
• TtfbOutcome::status() and TtfbOutcome::headers() return the status code
  and the headers of the final response. The types StatusCode and
  HeaderMap of the http crate are re-exported.

ttfb binary

• BREAKING The protocol is now chosen automatically by default: HTTP/3,
  then HTTP/2, then HTTP/1.1. Use --http1.1 for the previous behavior.
  For HTTPS servers without HTTP/3, the HTTP/3 attempt usually waits for its
  timeout of 1 s, which prolongs the run but not the measured timings.
• Added --http1.1, --http2, --http3, and --auto-protocol to select
  the HTTP protocol.
• Added --repeat N and --repeat Ns, which measure N times or repeatedly
  for N seconds and print the minimum, median, mean, and maximum of the
  relative and the absolute duration of each step.
• Added --timeout <SECS>, the maximum duration of a measurement, which
  defaults to 10 s and must be between 1 s and 3600 s.
• Added -4/--ipv4 and -6/--ipv6 to require an IP version. Without them,
  IPv4 is preferred as before.
• Added --headers, which prints the status line and the headers of the
  response.
• Added --json, which prints the results only as JSON in a single line, e.g.,
  for scripts. Its dependencies grow the release binary by 41 KiB (33 KiB
  stripped).
• The tables show the timings in ms with one decimal. More decimals only
  showed measurement noise. Durations below 0.05 ms are shown as <0.1.
• The output shows the IP address and port, the HTTP protocol, the status, and
  the download of the response.
• The output labels "TCP connect" and "HTTP GET Req" are now "TCP Connect"
  and "HTTP Send GET".
• The output shows the QUIC handshake of HTTP/3 measurements instead of the
  TCP connect and the TLS handshake.
• The release binary grows with the HTTP/2 and HTTP/3 support. On Linux,
  built with Rust 1.99 (sizes when stripped in parentheses):
  • v1.15.0: 3.2 MiB (2.5 MiB)
  • without http2 and http3: 3.2 MiB (2.5 MiB)
  • with http2: 3.5 MiB (2.8 MiB)
  • with http3: 4.0 MiB (3.2 MiB)
  • with http2 and http3, the default: 4.3 MiB (3.4 MiB)

PR List

• treewide: SPDX license headers and thiserror by @phip1611 in #119
• http1: correct response framing and content download timing by @phip1611 in #113
• http1: test response framing against well-known websites by @phip1611 in #121
• target, tls: shared target resolution and TLS configuration by @phip1611 in #123
• client: replace ttfb() with a configurable TtfbClient by @phip1611 in #124
• http2: HTTP/2 measurements by @phip1611 in #114
• outcome: TtfbTimings and the connection handshake enum by @phip1611 in #133
• http3: HTTP/3 measurements by @phip1611 in #116
• client: automatic protocol fallback by @phip1611 in #126
• cli: protocol selection options, docs by @phip1611 in #112
• http11: use the http crate's types by @phip1611 in #127
• http3: disable GREASE by @phip1611 in #135
• clippy: add clippy::absolute_paths by @phip1611 in #136
• cli: add --repeat by @phip1611 in #137
• Add a timeout for measurements by @phip1611 in #138
• Report the status and headers of the response by @phip1611 in #139
• cli: print the address, collect step durations in a helper by @phip1611 in #142
• cli: show the absolute durations with --repeat, round to 0.1 ms by @phip1611 in #144
• Add --ipv4 and --ipv6 by @phip1611 in #143
• test: give the network tests a timeout of 30 s by @phip1611 in #145
• cli: add --json by @phip1611 in #141
• error: compare the I/O errors of TtfbError by their variant by @phip1611 in #146
• lib: hide hickory-resolver's errors and fix the DNS timing by @phip1611 in #148
• lib: prepare the public API for minor releases after 2.0 by @phip1611 in #150
• ci: smoke-test the CLI with combinations of its options by @phip1611 in #151

Full Changelog: v1.15.0...v2.0.0