2021-09-07 14:13:19 -04:00

294 lines
11 KiB
Ruby

# typed: false
# frozen_string_literal: true
module Homebrew
module Livecheck
# The `Livecheck::Strategy` module contains the various strategies as well
# as some general-purpose methods for working with them. Within the context
# of the `brew livecheck` command, strategies are established procedures
# for finding new software versions at a given source.
#
# @api private
module Strategy
extend T::Sig
module_function
# {Strategy} priorities informally range from 1 to 10, where 10 is the
# highest priority. 5 is the default priority because it's roughly in
# the middle of this range. Strategies with a priority of 0 (or lower)
# are ignored.
DEFAULT_PRIORITY = 5
# cURL's default `--connect-timeout` value can be up to two minutes, so
# we need to use a more reasonable duration (in seconds) to avoid a
# lengthy wait when a connection can't be established.
CURL_CONNECT_TIMEOUT = 10
# cURL does not set a default `--max-time` value, so we provide a value
# to ensure cURL will time out in a reasonable amount of time.
CURL_MAX_TIME = CURL_CONNECT_TIMEOUT + 5
# The `curl` process will sometimes hang indefinitely (despite setting
# the `--max-time` argument) and it needs to be quit for livecheck to
# continue. This value is used to set the `timeout` argument on
# `Utils::Curl` method calls in {Strategy}.
CURL_PROCESS_TIMEOUT = CURL_MAX_TIME + 5
# Baseline `curl` arguments used in {Strategy} methods.
DEFAULT_CURL_ARGS = [
# Follow redirections to handle mirrors, relocations, etc.
"--location",
].freeze
# `curl` arguments used in `Strategy#page_headers` method.
PAGE_HEADERS_CURL_ARGS = ([
# We only need the response head (not the body)
"--head",
# Some servers may not allow a HEAD request, so we use GET
"--request", "GET",
"--silent"
] + DEFAULT_CURL_ARGS).freeze
# `curl` arguments used in `Strategy#page_content` method.
PAGE_CONTENT_CURL_ARGS = ([
"--compressed",
# Include HTTP response headers in output, so we can identify the
# final URL after any redirections
"--include",
] + DEFAULT_CURL_ARGS).freeze
# Baseline `curl` options used in {Strategy} methods.
DEFAULT_CURL_OPTIONS = {
print_stdout: false,
print_stderr: false,
debug: false,
verbose: false,
timeout: CURL_PROCESS_TIMEOUT,
connect_timeout: CURL_CONNECT_TIMEOUT,
max_time: CURL_MAX_TIME,
retries: 0,
}.freeze
# HTTP response head(s) and body are typically separated by a double
# `CRLF` (whereas HTTP header lines are separated by a single `CRLF`).
# In rare cases, this can also be a double newline (`\n\n`).
HTTP_HEAD_BODY_SEPARATOR = "\r\n\r\n"
# A regex used to identify a tarball extension at the end of a string.
TARBALL_EXTENSION_REGEX = /
\.t
(?:ar(?:\.(?:bz2|gz|lz|lzma|lzo|xz|Z|zst))?|
b2|bz2?|z2|az|gz|lz|lzma|xz|Z|aZ|zst)
$
/ix.freeze
# An error message to use when a `strategy` block returns a value of
# an inappropriate type.
INVALID_BLOCK_RETURN_VALUE_MSG = "Return value of a strategy block must be a string or array of strings."
# Creates and/or returns a `@strategies` `Hash`, which maps a snake
# case strategy name symbol (e.g. `:page_match`) to the associated
# strategy.
#
# At present, this should only be called after tap strategies have been
# loaded, otherwise livecheck won't be able to use them.
# @return [Hash]
sig { returns(T::Hash[Symbol, T.untyped]) }
def strategies
return @strategies if defined? @strategies
@strategies = {}
Strategy.constants.sort.each do |const_symbol|
constant = Strategy.const_get(const_symbol)
next unless constant.is_a?(Class)
key = const_symbol.to_s.underscore.to_sym
@strategies[key] = constant
end
@strategies
end
private_class_method :strategies
# Returns the strategy that corresponds to the provided `Symbol` (or
# `nil` if there is no matching strategy).
#
# @param symbol [Symbol, nil] the strategy name in snake case as a
# `Symbol` (e.g. `:page_match`)
# @return [Class, nil]
sig { params(symbol: T.nilable(Symbol)).returns(T.nilable(T.untyped)) }
def from_symbol(symbol)
strategies[symbol] if symbol.present?
end
# Returns an array of strategies that apply to the provided URL.
#
# @param url [String] the URL to check for matching strategies
# @param livecheck_strategy [Symbol] a strategy symbol from the
# `livecheck` block
# @param url_provided [Boolean] whether a url is provided in the
# `livecheck` block
# @param regex_provided [Boolean] whether a regex is provided in the
# `livecheck` block
# @param block_provided [Boolean] whether a `strategy` block is provided
# in the `livecheck` block
# @return [Array]
sig {
params(
url: String,
livecheck_strategy: T.nilable(Symbol),
url_provided: T::Boolean,
regex_provided: T::Boolean,
block_provided: T::Boolean,
).returns(T::Array[T.untyped])
}
def from_url(url, livecheck_strategy: nil, url_provided: false, regex_provided: false, block_provided: false)
usable_strategies = strategies.values.select do |strategy|
if strategy == PageMatch
# Only treat the `PageMatch` strategy as usable if a regex is
# present in the `livecheck` block
next if !regex_provided && !block_provided
elsif strategy.const_defined?(:PRIORITY) &&
!strategy::PRIORITY.positive? &&
from_symbol(livecheck_strategy) != strategy
# Ignore strategies with a priority of 0 or lower, unless the
# strategy is specified in the `livecheck` block
next
end
strategy.respond_to?(:match?) && strategy.match?(url)
end
# Sort usable strategies in descending order by priority, using the
# DEFAULT_PRIORITY when a strategy doesn't contain a PRIORITY constant
usable_strategies.sort_by do |strategy|
(strategy.const_defined?(:PRIORITY) ? -strategy::PRIORITY : -DEFAULT_PRIORITY)
end
end
# Collects HTTP response headers, starting with the provided URL.
# Redirections will be followed and all the response headers are
# collected into an array of hashes.
#
# @param url [String] the URL to fetch
# @return [Array]
sig { params(url: String).returns(T::Array[T::Hash[String, String]]) }
def self.page_headers(url)
headers = []
[:default, :browser].each do |user_agent|
stdout, _, status = curl_with_workarounds(
*PAGE_HEADERS_CURL_ARGS, url,
**DEFAULT_CURL_OPTIONS,
user_agent: user_agent
)
while stdout.match?(/\AHTTP.*\r$/)
h, stdout = stdout.split("\r\n\r\n", 2)
headers << h.split("\r\n").drop(1)
.map { |header| header.split(/:\s*/, 2) }
.to_h.transform_keys(&:downcase)
end
return headers if status.success?
end
headers
end
# Fetches the content at the URL and returns a hash containing the
# content and, if there are any redirections, the final URL.
# If `curl` encounters an error, the hash will contain a `:messages`
# array with the error message instead.
#
# @param url [String] the URL of the content to check
# @return [Hash]
sig { params(url: String).returns(T::Hash[Symbol, T.untyped]) }
def self.page_content(url)
original_url = url
stderr = nil
[:default, :browser].each do |user_agent|
stdout, stderr, status = curl_with_workarounds(
*PAGE_CONTENT_CURL_ARGS, url,
**DEFAULT_CURL_OPTIONS,
user_agent: user_agent
)
next unless status.success?
# stdout contains the header information followed by the page content.
# We use #scrub here to avoid "invalid byte sequence in UTF-8" errors.
output = stdout.scrub
# Separate the head(s)/body and identify the final URL (after any
# redirections)
max_iterations = 5
iterations = 0
output = output.lstrip
while output.match?(%r{\AHTTP/[\d.]+ \d+}) && output.include?(HTTP_HEAD_BODY_SEPARATOR)
iterations += 1
raise "Too many redirects (max = #{max_iterations})" if iterations > max_iterations
head_text, _, output = output.partition(HTTP_HEAD_BODY_SEPARATOR)
output = output.lstrip
location = head_text[/^Location:\s*(.*)$/i, 1]
next if location.blank?
location.chomp!
# Convert a relative redirect URL to an absolute URL
location = URI.join(url, location) unless location.match?(PageMatch::URL_MATCH_REGEX)
final_url = location
end
data = { content: output }
data[:final_url] = final_url if final_url.present? && final_url != original_url
return data
end
error_msgs = stderr&.scan(/^curl:.+$/)
{ messages: error_msgs.presence || ["cURL failed without a detectable error"] }
end
# Handles the return value from a `strategy` block in a `livecheck`
# block.
#
# @param value [] the return value from a `strategy` block
# @return [Array]
sig { params(value: T.untyped).returns(T::Array[String]) }
def self.handle_block_return(value)
case value
when String
[value]
when Array
value.compact.uniq
when nil
[]
else
raise TypeError, INVALID_BLOCK_RETURN_VALUE_MSG
end
end
end
end
end
require_relative "strategy/apache"
require_relative "strategy/bitbucket"
require_relative "strategy/cpan"
require_relative "strategy/electron_builder"
require_relative "strategy/extract_plist"
require_relative "strategy/git"
require_relative "strategy/github_latest"
require_relative "strategy/gnome"
require_relative "strategy/gnu"
require_relative "strategy/hackage"
require_relative "strategy/header_match"
require_relative "strategy/launchpad"
require_relative "strategy/npm"
require_relative "strategy/page_match"
require_relative "strategy/pypi"
require_relative "strategy/sourceforge"
require_relative "strategy/sparkle"
require_relative "strategy/xorg"