From 556d1d13ad6ce056fb52d920e36c08192c7103c5 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Sun, 16 Feb 2025 23:08:46 +0200
Subject: change foo[...] to foo(...) syntax for deps

test deps
---
 lib/dsl.rb                              |  2 +-
 lib/dslkeywords/keyword.rb              |  2 +-
 lib/dslkeywords/resource.rb             | 20 ++++++++------------
 test/lib/dslkeywords/dependency_test.rb | 25 +++++++++++++++++++------
 4 files changed, 29 insertions(+), 20 deletions(-)

diff --git a/lib/dsl.rb b/lib/dsl.rb
index caed790..b9062e5 100644
--- a/lib/dsl.rb
+++ b/lib/dsl.rb
@@ -25,7 +25,7 @@ module RCM
 
     def initialize(reset)
       DSL.reset! if reset
-      @id = "dsl[#{@@rcm_counter += 1}]"
+      @id = "dsl(#{@@rcm_counter += 1})"
       @conds_met = true
       @scheduled = []
       yield self if block_given?
diff --git a/lib/dslkeywords/keyword.rb b/lib/dslkeywords/keyword.rb
index 2696e41..2dfff91 100644
--- a/lib/dslkeywords/keyword.rb
+++ b/lib/dslkeywords/keyword.rb
@@ -9,7 +9,7 @@ module RCM
     include Options
     include Log
 
-    def initialize(name) = @id = "#{self.class.to_s.sub('RCM::', '').downcase}['#{name}']"
+    def initialize(name) = @id = "#{self.class.to_s.sub('RCM::', '').downcase}('#{name}')"
     def to_s = @id
   end
 end
diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index c9098d4..18239fc 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -13,31 +13,27 @@ module RCM
       end
     end
 
-    # Only to have the resourcename[id] syntax available in the DSL
-    class SyntaxSugar
-      def initialize(name) = @name = name
-      def [](other) = "#{@name}['#{other}']"
-    end
-
     class NoSuchResourceType < StandardError; end
 
-    def method_missing(method_name)
+    def method_missing(method_name, *args)
       raise NoSuchResourceType, "No such resource type: #{method_name}" unless @valid_resources.include?(method_name)
 
-      SyntaxSugar.new(method_name)
+      args.map { |arg| "#{method_name}('#{arg}')" }
     end
 
     def respond_to_missing? = true
 
     def depends_on(*others)
-      @dependencies = {} if @dependencies.nil?
-      others.each do |other|
+      @depends_on = {} if @depends_on.nil?
+      return @depends_on if others.empty?
+
+      others.flatten.each do |other|
         info "Registered dependency on #{other}"
-        @dependencies[other] = {}
+        @depends_on[other] = {}
       end
     end
 
-    def dependencies = @dependencies.nil ? [] : @dependencies
+    def depends_on?(other) = @depends_on.nil? ? false : @depends_on.key?(other)
   end
 
   # A resource is something concrete to be managed, e.g. a file, or a CRON job.
diff --git a/test/lib/dslkeywords/dependency_test.rb b/test/lib/dslkeywords/dependency_test.rb
index 324a756..393552f 100644
--- a/test/lib/dslkeywords/dependency_test.rb
+++ b/test/lib/dslkeywords/dependency_test.rb
@@ -5,25 +5,38 @@ require_relative '../../../lib/dsl'
 
 class RCMDependencyTest < Minitest::Test
   def test_depends_on
+    foo = nil
+    bar = nil
+    baz = nil
+
     configure_from_scratch do
-      notify 'foo' do
-        depends_on notify['bar'], notify['baz']
+      foo = notify 'foo' do
+        depends_on notify 'bar', 'baz'
         :foo_message
       end
 
-      notify 'bar'
+      bar = notify 'bar'
 
-      notify 'baz' do
-        depends_on notify['bar']
+      baz = notify 'baz' do
+        depends_on notify 'bar'
         :baz_message
       end
     end
+
+    assert_equal 2, foo.depends_on.keys.length
+    assert foo.depends_on?("notify('bar')")
+    assert foo.depends_on?("notify('baz')")
+
+    assert_equal 0, bar.depends_on.keys.length
+
+    assert_equal 1, baz.depends_on.keys.length
+    assert baz.depends_on?("notify('bar')")
   end
 
   def test_depends_on_invalid_resource
     assert_raises(RCM::ResourceDependencies::NoSuchResourceType) do
       configure_from_scratch do
-        notify { depends_on invalid['baz'] }
+        notify { depends_on invalid('baz') }
       end
     end
   end
-- 
cgit v1.2.3


From a246ade229a2a1578358eb25fe5855bc5cf22732 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Sun, 16 Feb 2025 23:15:45 +0200
Subject: sugar

---
 lib/dslkeywords/resource.rb             | 6 +++++-
 playground/Rakefile                     | 2 +-
 test/lib/dslkeywords/dependency_test.rb | 3 +--
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 18239fc..4c28809 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -33,7 +33,11 @@ module RCM
       end
     end
 
-    def depends_on?(other) = @depends_on.nil? ? false : @depends_on.key?(other)
+    def depends_on?(*others)
+      return false if @depends_on.nil?
+
+      others.flatten.none? { |other| !@depends_on.key?(other) }
+    end
   end
 
   # A resource is something concrete to be managed, e.g. a file, or a CRON job.
diff --git a/playground/Rakefile b/playground/Rakefile
index ef53d00..35ae811 100644
--- a/playground/Rakefile
+++ b/playground/Rakefile
@@ -37,7 +37,7 @@ task :foo do
   configure do
     file '/tmp/foo.txt' do
       ensure_line 'foo'
-      depends_on file['/tmp/bar.txt']
+      depends_on file '/tmp/bar.txt'
     end
 
     file '/tmp/bar.txt' do
diff --git a/test/lib/dslkeywords/dependency_test.rb b/test/lib/dslkeywords/dependency_test.rb
index 393552f..4a71485 100644
--- a/test/lib/dslkeywords/dependency_test.rb
+++ b/test/lib/dslkeywords/dependency_test.rb
@@ -24,8 +24,7 @@ class RCMDependencyTest < Minitest::Test
     end
 
     assert_equal 2, foo.depends_on.keys.length
-    assert foo.depends_on?("notify('bar')")
-    assert foo.depends_on?("notify('baz')")
+    assert foo.depends_on?("notify('bar')", "notify('baz')")
 
     assert_equal 0, bar.depends_on.keys.length
 
-- 
cgit v1.2.3


From d64135e44904500d65b029fb31216a52d507a7be Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Sun, 16 Feb 2025 23:49:20 +0200
Subject: can find resource objs

---
 lib/dslkeywords/file.rb                 |  1 +
 lib/dslkeywords/notify.rb               |  6 +++++-
 lib/dslkeywords/resource.rb             | 31 +++++++++++++++++++++++++++----
 test/lib/dslkeywords/dependency_test.rb |  9 +++++++++
 4 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/lib/dslkeywords/file.rb b/lib/dslkeywords/file.rb
index 501b7c8..b42f223 100644
--- a/lib/dslkeywords/file.rb
+++ b/lib/dslkeywords/file.rb
@@ -25,6 +25,7 @@ module RCM
     def ensure_line(line) = @ensure_line = line
 
     def evaluate!
+      return unless super
       return evaluate_ensure_line! unless @ensure_line.nil?
 
       write_content!(real_content)
diff --git a/lib/dslkeywords/notify.rb b/lib/dslkeywords/notify.rb
index 602d216..e1d8a3d 100644
--- a/lib/dslkeywords/notify.rb
+++ b/lib/dslkeywords/notify.rb
@@ -15,7 +15,11 @@ module RCM
       @message = msg unless msg.nil?
     end
 
-    def evaluate! = puts "#{id} => #{@message}"
+    def evaluate!
+      return unless super
+
+      puts "#{id} => #{@message}"
+    end
   end
 
   # Add notify keyword to the DSL
diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 4c28809..1634061 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -29,19 +29,42 @@ module RCM
 
       others.flatten.each do |other|
         info "Registered dependency on #{other}"
-        @depends_on[other] = {}
+        @depends_on[other] = nil
       end
     end
 
-    def depends_on?(*others)
-      return false if @depends_on.nil?
+    def depends_on?(*others) = others.flatten.none? { |other| !@depends_on&.key?(other) }
+  end
+
+  # To resolve dependencies
+  module DependencyEvaluator
+    attr_reader :evaluated
+
+    def evaluate!
+      return false if @evaluated
+
+      @depends_on = {} if @depends_on.nil?
+      @depends_on.each_key do |id|
+        dependency = Resource.find(id)
+      end
 
-      others.flatten.none? { |other| !@depends_on.key?(other) }
+      @evaluated = true
     end
   end
 
   # A resource is something concrete to be managed, e.g. a file, or a CRON job.
   class Resource < Keyword
+    include DependencyEvaluator
     include ResourceDependencies
+
+    class NoSuchResourceObject < StandardError; end
+
+    def self.find(id)
+      klass = Object.const_get("RCM::#{id.split('(').first.capitalize}")
+      resource = ObjectSpace.each_object(klass).find { |obj| obj.id == id }
+      raise NoSuchResourceObject, "Unable to find resource #{id}" if resource.nil?
+
+      resource
+    end
   end
 end
diff --git a/test/lib/dslkeywords/dependency_test.rb b/test/lib/dslkeywords/dependency_test.rb
index 4a71485..e9bc205 100644
--- a/test/lib/dslkeywords/dependency_test.rb
+++ b/test/lib/dslkeywords/dependency_test.rb
@@ -27,6 +27,7 @@ class RCMDependencyTest < Minitest::Test
     assert foo.depends_on?("notify('bar')", "notify('baz')")
 
     assert_equal 0, bar.depends_on.keys.length
+    refute bar.depends_on?('foo')
 
     assert_equal 1, baz.depends_on.keys.length
     assert baz.depends_on?("notify('bar')")
@@ -39,4 +40,12 @@ class RCMDependencyTest < Minitest::Test
       end
     end
   end
+
+  def test_depends_on_non_existant_dependency
+    assert_raises(RCM::Resource::NoSuchResourceObject) do
+      configure_from_scratch do
+        notify { depends_on notify('nonexistant') }
+      end
+    end
+  end
 end
-- 
cgit v1.2.3


From ed8cf0c0c285abab24479b7af3bc73f2c7340822 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Mon, 17 Feb 2025 00:12:20 +0200
Subject: can detect dependency loop

---
 lib/dslkeywords/resource.rb             | 19 +++++++++++++++----
 test/lib/dslkeywords/dependency_test.rb | 17 +++++++++++++++++
 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 1634061..2320077 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -40,14 +40,25 @@ module RCM
   module DependencyEvaluator
     attr_reader :evaluated
 
+    class DependencyLoop < StandardError; end
+    class UnresolvedDependency < StandardError; end
+
     def evaluate!
       return false if @evaluated
 
+      raise DependencyLoop, "Dependency loop detected for #{id}" if @loop_detection
+
+      @loop_detection = true
       @depends_on = {} if @depends_on.nil?
-      @depends_on.each_key do |id|
-        dependency = Resource.find(id)
-      end
 
+      # Try to evaluate all dependencies recursively.
+      @depends_on.each_key.map { Resource.find(_1) }.each(&:evaluate!)
+
+      # Raise an exception when there are still unresolved dependencies.
+      unresolved = @depends_on.each_key.map { Resource.find(_1) }.reject(&:evaluated)
+      raise UnresolvedDependency, "Unresolved dependencies: #{unresolved.map(&:id)}" if unresolved.count.positive?
+
+      @loop_detection = false
       @evaluated = true
     end
   end
@@ -61,7 +72,7 @@ module RCM
 
     def self.find(id)
       klass = Object.const_get("RCM::#{id.split('(').first.capitalize}")
-      resource = ObjectSpace.each_object(klass).find { |obj| obj.id == id }
+      resource = ObjectSpace.each_object(klass).find { _1.id == id }
       raise NoSuchResourceObject, "Unable to find resource #{id}" if resource.nil?
 
       resource
diff --git a/test/lib/dslkeywords/dependency_test.rb b/test/lib/dslkeywords/dependency_test.rb
index e9bc205..f1280eb 100644
--- a/test/lib/dslkeywords/dependency_test.rb
+++ b/test/lib/dslkeywords/dependency_test.rb
@@ -48,4 +48,21 @@ class RCMDependencyTest < Minitest::Test
       end
     end
   end
+
+  def test_dependency_loop
+    assert_raises(RCM::DependencyEvaluator::DependencyLoop) do
+      configure_from_scratch do
+        notify('loop') { depends_on notify('loop') }
+      end
+    end
+  end
+
+  def test_dependency_loop_indirect
+    assert_raises(RCM::DependencyEvaluator::DependencyLoop) do
+      configure_from_scratch do
+        notify('loop') { depends_on notify('pool') }
+        notify('pool') { depends_on notify('loop') }
+      end
+    end
+  end
 end
-- 
cgit v1.2.3


From a8d7029846faff9db5a99dbe011b3765a1350ee4 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Mon, 17 Feb 2025 00:16:47 +0200
Subject: sugar

---
 TODO.md                     | 1 -
 lib/dslkeywords/resource.rb | 3 +--
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/TODO.md b/TODO.md
index ad66ca3..1f83cad 100644
--- a/TODO.md
+++ b/TODO.md
@@ -16,7 +16,6 @@
 * Binary installation support (file copy from source to dest)
   * Local file system
   * scp? git? http/s?
-* Object dependencies / ensuring correct order of evaluation
 * Manage services (start, stop, restart (subscribe))
 * Manage packages (install, update, deinstall)
   * Fedora
diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 2320077..29824e9 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -7,6 +7,7 @@ module RCM
   module ResourceDependencies
     def initialize(...)
       super(...)
+      @depends_on = {}
       @valid_resources = Set.new
       ObjectSpace.each_object(Class).each do |klass|
         @valid_resources << klass.to_s.sub('RCM::', '').downcase.to_sym if klass < Resource
@@ -24,7 +25,6 @@ module RCM
     def respond_to_missing? = true
 
     def depends_on(*others)
-      @depends_on = {} if @depends_on.nil?
       return @depends_on if others.empty?
 
       others.flatten.each do |other|
@@ -49,7 +49,6 @@ module RCM
       raise DependencyLoop, "Dependency loop detected for #{id}" if @loop_detection
 
       @loop_detection = true
-      @depends_on = {} if @depends_on.nil?
 
       # Try to evaluate all dependencies recursively.
       @depends_on.each_key.map { Resource.find(_1) }.each(&:evaluate!)
-- 
cgit v1.2.3


From e13d1a0a7df840bd86e68f6b9604c764c54cc60f Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Mon, 17 Feb 2025 00:20:47 +0200
Subject: use a set

---
 lib/dslkeywords/resource.rb             | 10 +++++-----
 test/lib/dslkeywords/dependency_test.rb |  6 +++---
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 29824e9..11df70e 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -7,7 +7,7 @@ module RCM
   module ResourceDependencies
     def initialize(...)
       super(...)
-      @depends_on = {}
+      @depends_on = Set.new
       @valid_resources = Set.new
       ObjectSpace.each_object(Class).each do |klass|
         @valid_resources << klass.to_s.sub('RCM::', '').downcase.to_sym if klass < Resource
@@ -29,11 +29,11 @@ module RCM
 
       others.flatten.each do |other|
         info "Registered dependency on #{other}"
-        @depends_on[other] = nil
+        @depends_on << other
       end
     end
 
-    def depends_on?(*others) = others.flatten.none? { |other| !@depends_on&.key?(other) }
+    def depends_on?(*others) = others.flatten.none? { |other| !@depends_on&.include?(other) }
   end
 
   # To resolve dependencies
@@ -51,10 +51,10 @@ module RCM
       @loop_detection = true
 
       # Try to evaluate all dependencies recursively.
-      @depends_on.each_key.map { Resource.find(_1) }.each(&:evaluate!)
+      @depends_on.each.map { Resource.find(_1) }.each(&:evaluate!)
 
       # Raise an exception when there are still unresolved dependencies.
-      unresolved = @depends_on.each_key.map { Resource.find(_1) }.reject(&:evaluated)
+      unresolved = @depends_on.each.map { Resource.find(_1) }.reject(&:evaluated)
       raise UnresolvedDependency, "Unresolved dependencies: #{unresolved.map(&:id)}" if unresolved.count.positive?
 
       @loop_detection = false
diff --git a/test/lib/dslkeywords/dependency_test.rb b/test/lib/dslkeywords/dependency_test.rb
index f1280eb..aeb2790 100644
--- a/test/lib/dslkeywords/dependency_test.rb
+++ b/test/lib/dslkeywords/dependency_test.rb
@@ -23,13 +23,13 @@ class RCMDependencyTest < Minitest::Test
       end
     end
 
-    assert_equal 2, foo.depends_on.keys.length
+    assert_equal 2, foo.depends_on.count
     assert foo.depends_on?("notify('bar')", "notify('baz')")
 
-    assert_equal 0, bar.depends_on.keys.length
+    assert_equal 0, bar.depends_on.count
     refute bar.depends_on?('foo')
 
-    assert_equal 1, baz.depends_on.keys.length
+    assert_equal 1, baz.depends_on.count
     assert baz.depends_on?("notify('bar')")
   end
 
-- 
cgit v1.2.3


From 9bb314cb170a651571b57767d33b3c01112aa5bc Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Mon, 17 Feb 2025 00:26:07 +0200
Subject: cache the resource objs

---
 lib/dslkeywords/resource.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index 11df70e..f646030 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -69,12 +69,16 @@ module RCM
 
     class NoSuchResourceObject < StandardError; end
 
+    @@resource_find_cache = {}
+
     def self.find(id)
+      return @@resource_find_cache[id] if @@resource_find_cache.key?(id)
+
       klass = Object.const_get("RCM::#{id.split('(').first.capitalize}")
       resource = ObjectSpace.each_object(klass).find { _1.id == id }
       raise NoSuchResourceObject, "Unable to find resource #{id}" if resource.nil?
 
-      resource
+      @@resource_find_cache[id] = resource
     end
   end
 end
-- 
cgit v1.2.3


From 614a3b5062d3a37d7f1eb59ad47e4ec5d791edc6 Mon Sep 17 00:00:00 2001
From: Paul Buetow <paul@buetow.org>
Date: Tue, 18 Feb 2025 10:46:44 +0200
Subject: backupping file when change

---
 TODO.md                     |  1 -
 lib/dslkeywords/file.rb     | 22 +++++++++++++++++++++-
 lib/dslkeywords/resource.rb |  2 ++
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/TODO.md b/TODO.md
index 1f83cad..120fec9 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,7 +1,6 @@
 # TODO
 
 * Recursively install a directory
-* Backup of files when changed
 * Support for file deletion
 * Support for file modes (owner, chmod)
 * Support for symlinks
diff --git a/lib/dslkeywords/file.rb b/lib/dslkeywords/file.rb
index b42f223..e83906e 100644
--- a/lib/dslkeywords/file.rb
+++ b/lib/dslkeywords/file.rb
@@ -1,13 +1,32 @@
+require 'digest'
 require 'erb'
 require 'fileutils'
 
 require_relative 'resource'
 
 module RCM
+  # Backup the file on change
+  module FileBackup
+    def backup!(path)
+      return unless ::File.exist?(path)
+
+      backup_dir = "#{::File.dirname(path)}/.rcm"
+      Dir.mkdir(backup_dir) unless ::File.directory?(backup_dir)
+      checksum = Digest::SHA256.file(path).hexdigest
+      backup_path = "#{backup_dir}/#{::File.basename(path)}.#{checksum}"
+      return if ::File.exist?(backup_path)
+
+      info("Backing up #{path} -> #{backup_path}")
+      ::File.rename(path, backup_path)
+    end
+  end
+
   # Managing files
   class File < Resource
     attr_reader :path
 
+    include FileBackup
+
     def initialize(path)
       super(path)
       @path = path
@@ -45,9 +64,10 @@ module RCM
     def write_content!(text)
       create_parent_directory!
       debug text if option :debug
-      info "Creating file #{@path}"
+      info "Managing file #{@path}"
       tmp_path = "#{@path}.tmp"
       ::File.write(tmp_path, text)
+      backup!(@path)
       ::File.rename(tmp_path, @path)
     end
 
diff --git a/lib/dslkeywords/resource.rb b/lib/dslkeywords/resource.rb
index f646030..f665a50 100644
--- a/lib/dslkeywords/resource.rb
+++ b/lib/dslkeywords/resource.rb
@@ -69,6 +69,8 @@ module RCM
 
     class NoSuchResourceObject < StandardError; end
 
+    # TODO: Detect duplicate resource definition
+
     @@resource_find_cache = {}
 
     def self.find(id)
-- 
cgit v1.2.3