Class: Browsable::Config

Inherits:
Object
  • Object
show all
Defined in:
lib/browsable/config.rb

Overview

Resolves the effective configuration for an audit run.

browsable runs fully zero-config: when no config file is present every value below is inferred. A config file only exists to override defaults.

Resolution precedence (highest wins) is applied by the caller:

1. CLI flags        (handled in CLI)
2. config file      (loaded here)
3. inferred Rails   (allow_browser policy, read here)
4. gem defaults     (DEFAULTS below)

Constant Summary collapse

DEFAULTS = 
{
  "target" => {
    "source"       => "allow_browsers", # allow_browsers | browserslist | manual
    "manual_query" => "defaults"
  },
  "sources" => {
    "stylesheets" => ["app/assets/stylesheets/**/*.{css,scss,sass}"],
    "builds"      => ["app/assets/builds/**/*.css"],
    "views"       => ["app/views/**/*.{html.erb,turbo_stream.erb}",
                      "app/components/**/*.{rb,html.erb}"],
    # `app/javascript` is the Propshaft/importmap convention;
    # `app/assets/javascripts` is the Sprockets convention. Globbing both
    # is harmless on a Propshaft-only app (no files match) and lets the
    # CLI work on Sprockets apps with zero configuration.
    "javascript"  => ["app/javascript/**/*.{js,mjs}",
                      "app/assets/javascripts/**/*.{js,mjs}"],
    "importmap"   => true,
    "public"      => ["public/**/*.{html,css,js}"],
    "custom"      => []
  },
  "severity" => {
    "baseline_newly_available" => "warning",
    "baseline_limited"         => "error",
    "below_target"             => "error"
  },
  "ignore" => {
    "features" => [],
    "files"    => []
  }
}.freeze
CONFIG_FILENAMES =

Discovery order for an implicit config file, relative to the project root.

["config/browsable.yml", ".browsable.yml"].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(root:, data:, config_file: nil) ⇒ Config

Returns a new instance of Config.



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# File 'lib/browsable/config.rb', line 97

def initialize(root:, data:, config_file: nil)
  @root = root
  @data = data
  @config_file = config_file
  # PolicyDetector statically resolves the Rails allow_browser policy.
  # `policy_note` is set when a call was found but could not be resolved.
  result = PolicyDetector.call(root)
  @detected_policy = result.policy
  @policy_note = result.note
end

Instance Attribute Details

#config_file ⇒ Object (readonly)

Returns the value of attribute config_file.



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# File 'lib/browsable/config.rb', line 51

def config_file
  @config_file
end

#data ⇒ Object (readonly)

Returns the value of attribute data.



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# File 'lib/browsable/config.rb', line 51

def data
  @data
end

#detected_policy ⇒ Object (readonly)

Returns the value of attribute detected_policy.



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# File 'lib/browsable/config.rb', line 51

def detected_policy
  @detected_policy
end

#policy_note ⇒ Object (readonly)

Returns the value of attribute policy_note.



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# File 'lib/browsable/config.rb', line 51

def policy_note
  @policy_note
end

#root ⇒ Object (readonly)

Returns the value of attribute root.



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# File 'lib/browsable/config.rb', line 51

def root
  @root
end

Class Method Details

.deep_merge(base, override) ⇒ Object 



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# File 'lib/browsable/config.rb', line 87

def self.deep_merge(base, override)
  base.merge(override) do |_key, base_val, override_val|
    if base_val.is_a?(Hash) && override_val.is_a?(Hash)
      deep_merge(base_val, override_val)
    else
      override_val
    end
  end
end

.load(root:, path: nil) ⇒ Object

Load and merge configuration for a project rooted at ‘root`.

Parameters:

  • root (String) —

    the Rails app (or project) root

  • path (String, nil) (defaults to: nil) —

    an explicit config file path (from –config)



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# File 'lib/browsable/config.rb', line 57

def self.load(root:, path: nil)
  root = File.expand_path(root)
  config_file = locate_file(root, path)
  file_data = config_file ? parse_file(config_file) : {}
  merged = deep_merge(DEFAULTS, file_data)
  new(root: root, data: merged, config_file: config_file)
end

.locate_file(root, explicit) ⇒ Object 



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# File 'lib/browsable/config.rb', line 65

def self.locate_file(root, explicit)
  if explicit
    full = File.expand_path(explicit, root)
    raise ConfigError, "Config file not found: #{explicit}" unless File.file?(full)

    return full
  end

  CONFIG_FILENAMES
    .map { |name| File.join(root, name) }
    .find { |candidate| File.file?(candidate) }
end

.parse_file(path) ⇒ Object 



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# File 'lib/browsable/config.rb', line 78

def self.parse_file(path)
  loaded = YAML.safe_load_file(path) || {}
  raise ConfigError, "#{path} must contain a YAML mapping" unless loaded.is_a?(Hash)

  loaded
rescue Psych::SyntaxError => e
  raise ConfigError, "Could not parse #{path}: #{e.message}"
end

Instance Method Details

#file_present? ⇒ Boolean

True when an explicit config file was found and loaded.

Returns:

  • (Boolean) 


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# File 'lib/browsable/config.rb', line 166

def file_present? = !config_file.nil?

#ignore_features ⇒ Object 



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# File 'lib/browsable/config.rb', line 110

def ignore_features = Array(data.dig("ignore", "features"))

#ignore_files ⇒ Object 



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# File 'lib/browsable/config.rb', line 111

def ignore_files    = Array(data.dig("ignore", "files"))

#importmap_enabled? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/browsable/config.rb', line 112

def importmap_enabled? = sources.fetch("importmap", true) != false

#severity ⇒ Object 



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# File 'lib/browsable/config.rb', line 109

def severity      = data.fetch("severity")

#sources ⇒ Object 



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# File 'lib/browsable/config.rb', line 108

def sources       = data.fetch("sources")

#target ⇒ Object

Resolve the browser-support Target implied by this config.



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# File 'lib/browsable/config.rb', line 115

def target
  cfg = data.fetch("target")
  case cfg["source"]
  when "manual"
    Target.new(cfg.fetch("manual_query", "defaults"))
  when "browserslist"
    # Defer entirely to the project's browserslist config (.browserslistrc).
    Target.new("defaults")
  else # "allow_browsers" (the default)
    detected_policy ? Target.from_rails_policy(detected_policy) : Target.new("defaults")
  end
end

#target_notes ⇒ Object

Informational caveats about the resolved target — so the user is never left guessing why a particular set of browsers is (or isn’t) audited.



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# File 'lib/browsable/config.rb', line 140

def target_notes
  notes = []
  inferring = data.dig("target", "source") == "allow_browsers"

  # No allow_browser policy at all — explain the browserslist defaults fallback.
  if inferring && detected_policy.nil? && policy_note.nil?
    notes << "No allow_browser policy was found in ApplicationController, so browsable " \
             "is auditing against the browserslist `defaults` baseline. Add an " \
             "allow_browser call, or set `target:` in config/browsable.yml, to pick the " \
             "browsers to audit against explicitly."
  end

  # A partial hash policy — explain the browsers Rails leaves unconstrained.
  if unconstrained_browsers.any?
    pinned = detected_policy.keys.join(", ")
    omitted = unconstrained_browsers.join(", ")
    notes << "Your allow_browser policy pins a version only for #{pinned}. Rails leaves " \
             "every browser you don't list (#{omitted}) allowed at any version, so " \
             "browsable audits only #{pinned}. Add a `target:` block to " \
             "config/browsable.yml to audit the others."
  end

  notes
end

#unconstrained_browsers ⇒ Object

Major browsers an explicit allow_browser hash neither pins to a version nor blocks. Rails allows these at any version — it only ever blocks a browser it was given a minimum (or ‘false`) for — so browsable has no floor to audit them against. Empty unless the policy is an explicit hash.



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# File 'lib/browsable/config.rb', line 132

def unconstrained_browsers
  return [] unless detected_policy.is_a?(Hash)

  Target::MODERN.keys - detected_policy.keys
end