Add --cache option to inspec exec

This allows users to run:

  inspec exec ./ --cache PATH

which will use `PATH` as the dir to retrieve and store remote
dependencies.  The hope is that this can eventually be used with
`inspec vendor PATH` to package up a profile for offline use.

Signed-off-by: Steven Danna <steve@chef.io>

lib/inspec/base_cli.rb

@@ -58,6 +58,8 @@ module Inspec
         desc: 'Use colors in output.'
       option :attrs, type: :array,
         desc: 'Load attributes file (experimental)'
+      option :cache, type: :string,
+        desc: 'Use the given path for caching dependencies. (default: ~/.inspec/cache)'
     end
 
     private

lib/inspec/cli.rb

@@ -102,8 +102,8 @@ class Inspec::InspecCLI < Inspec::BaseCLI # rubocop:disable Metrics/ClassLength
   desc 'vendor', 'Download all dependencies and generate a lockfile'
   def vendor(path = nil)
     configure_logger(opts)
-    profile = Inspec::Profile.for_target('./', opts)
-    lockfile = profile.generate_lockfile(path)
+    profile = Inspec::Profile.for_target('./', opts.merge(cache: Inspec::Cache.new(path)))
+    lockfile = profile.generate_lockfile
     File.write('inspec.lock', lockfile.to_yaml)
   end
 

lib/inspec/dependencies/cache.rb

@@ -4,7 +4,7 @@ require 'fileutils'
 
 module Inspec
   #
-  # VendorIndex manages an on-disk cache of inspec profiles.  The
+  # Inspec::Cache manages an on-disk cache of inspec profiles.  The
   # cache can contain:
   #
   #  - .tar.gz profile archives
@@ -16,7 +16,7 @@ module Inspec
   # sources.
   #
   #
-  class VendorIndex
+  class Cache
     attr_reader :path
     def initialize(path = nil)
       @path = path || File.join(Dir.home, '.inspec', 'cache')
@@ -43,7 +43,7 @@ module Inspec
 
     #
     # For a given name and source_url, return true if the
-    # profile exists in the VendorIndex.
+    # profile exists in the Cache.
     #
     # @param [String] name
     # @param [String] source_url
@@ -56,7 +56,7 @@ module Inspec
     end
 
     #
-    # Return the path to given profile in the vendor index.
+    # Return the path to given profile in the cache.
     #
     # The `source_url` parameter should be a URI-like string that
     # fully specifies the source of the exact version we want to pull

lib/inspec/dependencies/dependency_set.rb

@@ -1,5 +1,4 @@
 # encoding: utf-8
-require 'inspec/dependencies/vendor_index'
 require 'inspec/dependencies/requirement'
 require 'inspec/dependencies/resolver'
 
@@ -7,9 +6,6 @@ module Inspec
   #
   # A DependencySet manages a list of dependencies for a profile.
   #
-  # Currently this class is a thin wrapper interface to coordinate the
-  # VendorIndex and the Resolver.
-  #
   class DependencySet
     #
     # Return a dependency set given a lockfile.
@@ -18,22 +14,21 @@ module Inspec
     # @param cwd [String] Current working directory for relative path includes
     # @param vendor_path [String] Path to the vendor directory
     #
-    def self.from_lockfile(lockfile, cwd, vendor_path, backend)
-      vendor_index = VendorIndex.new(vendor_path)
+    def self.from_lockfile(lockfile, cwd, cache, backend)
       dep_tree = lockfile.deps.map do |dep|
-        Inspec::Requirement.from_lock_entry(dep, cwd, vendor_index, backend)
+        Inspec::Requirement.from_lock_entry(dep, cwd, cache, backend)
       end
 
       dep_list = flatten_dep_tree(dep_tree)
-      new(cwd, vendor_path, dep_list, backend)
+      new(cwd, cache, dep_list, backend)
     end
 
-    def self.from_array(dependencies, cwd, vendor_path, backend)
+    def self.from_array(dependencies, cwd, cache, backend)
       dep_list = {}
       dependencies.each do |d|
         dep_list[d.name] = d
       end
-      new(cwd, vendor_path, dep_list, backend)
+      new(cwd, cache, dep_list, backend)
     end
 
     # This is experimental code to test the working of the
@@ -58,9 +53,9 @@ module Inspec
     # @param cwd [String] current working directory for relative path includes
     # @param vendor_path [String] path which contains vendored dependencies
     # @return [dependencies] this
-    def initialize(cwd, vendor_path, dep_list, backend)
+    def initialize(cwd, cache, dep_list, backend)
       @cwd = cwd
-      @vendor_path = vendor_path
+      @cache = cache
       @dep_list = dep_list
       @backend = backend
     end
@@ -91,8 +86,7 @@ module Inspec
     #
     def vendor(dependencies)
       return nil if dependencies.nil? || dependencies.empty?
-      @vendor_index ||= VendorIndex.new(@vendor_path)
-      @dep_list = Resolver.resolve(dependencies, @vendor_index, @cwd, @backend)
+      @dep_list = Resolver.resolve(dependencies, @cache, @cwd, @backend)
     end
   end
 end

lib/inspec/dependencies/requirement.rb

@@ -9,31 +9,31 @@ module Inspec
   # appropriate we delegate to Inspec::Profile directly.
   #
   class Requirement
-    def self.from_metadata(dep, vendor_index, opts)
+    def self.from_metadata(dep, cache, opts)
       fail 'Cannot load empty dependency.' if dep.nil? || dep.empty?
-      new(dep[:name], dep[:version], vendor_index, opts[:cwd], opts.merge(dep))
+      new(dep[:name], dep[:version], cache, opts[:cwd], opts.merge(dep))
     end
 
-    def self.from_lock_entry(entry, cwd, vendor_index, backend)
+    def self.from_lock_entry(entry, cwd, cache, backend)
       req = new(entry[:name],
                 entry[:version_constraints],
-                vendor_index,
+                cache,
                 cwd,
                 entry[:resolved_source].merge(backend: backend))
 
       locked_deps = []
       Array(entry[:dependencies]).each do |dep_entry|
-        locked_deps << Inspec::Requirement.from_lock_entry(dep_entry, cwd, vendor_index, backend)
+        locked_deps << Inspec::Requirement.from_lock_entry(dep_entry, cwd, cache, backend)
       end
       req.lock_deps(locked_deps)
       req
     end
 
     attr_reader :cwd, :opts, :required_version
-    def initialize(name, version_constraints, vendor_index, cwd, opts)
+    def initialize(name, version_constraints, cache, cwd, opts)
       @name = name
       @required_version = Gem::Requirement.new(Array(version_constraints))
-      @vendor_index = vendor_index
+      @cache = cache
       @backend = opts[:backend]
       @opts = opts
       @cwd = cwd
@@ -89,7 +89,7 @@ module Inspec
 
     def dependencies
       @dependencies ||= profile.metadata.dependencies.map do |r|
-        Inspec::Requirement.from_metadata(r, @vendor_index, cwd: @cwd, backend: @backend)
+        Inspec::Requirement.from_metadata(r, @cache, cwd: @cwd, backend: @backend)
       end
     end
 
@@ -99,10 +99,10 @@ module Inspec
 
     def profile
       opts = @opts.dup
-      opts[:cache] = @vendor_index
+      opts[:cache] = @cache
       opts[:backend] = @backend
       if !@dependencies.nil?
-        opts[:dependencies] = Inspec::DependencySet.from_array(@dependencies, @cwd, @vendor_index, @backend)
+        opts[:dependencies] = Inspec::DependencySet.from_array(@dependencies, @cwd, @cache, @backend)
       end
       @profile ||= Inspec::Profile.for_target(opts, opts)
     end

lib/inspec/dependencies/resolver.rb

@@ -23,9 +23,9 @@ module Inspec
   # implementation of the fetcher being used.
   #
   class Resolver
-    def self.resolve(dependencies, vendor_index, working_dir, backend)
+    def self.resolve(dependencies, cache, working_dir, backend)
       reqs = dependencies.map do |dep|
-        req = Inspec::Requirement.from_metadata(dep, vendor_index, cwd: working_dir, backend: backend)
+        req = Inspec::Requirement.from_metadata(dep, cache, cwd: working_dir, backend: backend)
         req || fail("Cannot initialize dependency: #{req}")
       end
       new.resolve(reqs)

lib/inspec/profile.rb

@@ -13,7 +13,7 @@ require 'inspec/backend'
 require 'inspec/rule'
 require 'inspec/log'
 require 'inspec/profile_context'
-require 'inspec/dependencies/vendor_index'
+require 'inspec/dependencies/cache'
 require 'inspec/dependencies/lockfile'
 require 'inspec/dependencies/dependency_set'
 
@@ -25,7 +25,7 @@ module Inspec
     # TODO: This function is getting pretty gross.
     #
     def self.resolve_target(target, cache = nil)
-      cache ||= VendorIndex.new
+      cache ||= Cache.new
       fetcher = Inspec::Fetcher.resolve(target)
 
       if fetcher.nil?
@@ -88,6 +88,7 @@ EOF
       @locked_dependencies = options[:dependencies]
       @controls = options[:controls] || []
       @profile_id = options[:id]
+      @cache = options[:cache] || Cache.new
       @backend = options[:backend] || Inspec::Backend.create(options)
       @source_reader = source_reader
       @tests_collected = false
@@ -368,14 +369,14 @@ EOF
     # @param vendor_path [String] Path to the on-disk vendor dir
     # @return [Inspec::Lockfile]
     #
-    def generate_lockfile(vendor_path = nil)
-      res = Inspec::DependencySet.new(cwd, vendor_path, nil, @backend)
+    def generate_lockfile
+      res = Inspec::DependencySet.new(cwd, @cache, nil, @backend)
       res.vendor(metadata.dependencies)
       Inspec::Lockfile.from_dependency_set(res)
     end
 
     def load_dependencies
-      Inspec::DependencySet.from_lockfile(lockfile, cwd, nil, @backend)
+      Inspec::DependencySet.from_lockfile(lockfile, cwd, @cache, @backend)
     end
 
     private

lib/inspec/runner.rb

@@ -11,6 +11,7 @@ require 'inspec/profile_context'
 require 'inspec/profile'
 require 'inspec/metadata'
 require 'inspec/secrets'
+require 'inspec/dependencies/cache'
 # spec requirements
 
 module Inspec
@@ -41,7 +42,7 @@ module Inspec
       @target_profiles = []
       @controls = @conf[:controls] || []
       @ignore_supports = @conf[:ignore_supports]
-
+      @cache = Inspec::Cache.new(@conf[:cache])
       @test_collector = @conf.delete(:test_collector) || begin
         require 'inspec/runner_rspec'
         RunnerRspec.new(@conf)
@@ -140,6 +141,7 @@ module Inspec
     #
     def add_target(target, _opts = [])
       profile = Inspec::Profile.for_target(target,
+                                           cache: @cache,
                                            backend: @backend,
                                            controls: @controls,
                                            attributes: @conf[:attributes])