Merging r1468 from the implementations branch with r1438 from when the branch was first created.

git-svn-id: https://reductivelabs.com/svn/puppet/trunk@1469 980ebf18-57e1-0310-9a29-db15c13687c0

1 files changed, 134 insertions, 0 deletions

diff --git a/lib/puppet/provider.rb b/lib/puppet/provider.rb
new file mode 100644
index 000000000..44851c16b
--- /dev/null
+++ b/lib/puppet/provider.rb
@@ -0,0 +1,134 @@
+# The container class for implementations.
+class Puppet::Provider
+    include Puppet::Util
+
+    Puppet::Util.logmethods(self, true)
+
+    class << self
+        # Include the util module so we have access to things like 'binary'
+        include Puppet::Util
+        attr_accessor :name, :model, :doc
+    end
+
+    attr_accessor :model
+    
+    def self.command(name)
+        name = symbolize(name)
+
+        if command = @commands[name]
+            return command
+        elsif superclass.respond_to? :command and command = superclass.command(name)
+            return command
+        else
+            raise Puppet::DevError, "No command %s defined for provider %s" %
+                [name, self.name]
+        end
+    end
+
+    # Define one or more binaries we'll be using
+    def self.commands(hash)
+        hash.each do |name, path|
+            name = symbolize(name)
+            path = binary(path) unless path =~ /^\//
+            @commands[name] = path
+            confine :exists => path
+        end
+    end
+
+    def self.confine(hash)
+        hash.each do |p,v|
+            if v.is_a? Array
+                @confines[p] += v
+            else
+                @confines[p] << v
+            end
+        end
+    end
+
+    # Does this implementation match all of the default requirements?
+    def self.default?
+        if @defaults.find do |fact, value|
+                Facter[fact].value.to_s.downcase.intern != value.to_s.downcase.intern
+            end
+            return false
+        else
+            return true
+        end
+    end
+
+    # Store how to determine defaults.
+    def self.defaultfor(hash)
+        hash.each do |d,v|
+            @defaults[d] = v
+        end
+    end
+
+    def self.defaultnum
+        @defaults.length
+    end
+
+    # Specify a documentation string.
+    def self.desc(str)
+        @doc = str
+    end
+
+    def self.initvars
+        @defaults = {}
+        @commands = {}
+        @confines = Hash.new do |hash, key|
+            hash[key] = []
+        end
+    end
+
+    self.initvars
+
+    # Check whether this implementation is suitable for our platform.
+    def self.suitable?
+        # A single false result is sufficient to turn the whole thing down.
+        @confines.each do |check, values|
+            case check
+            when :exists:
+                values.each do |value|
+                    unless value and FileTest.exists? value
+                        return false
+                    end
+                end
+            when :true:
+                values.each do |v|
+                    return false unless v
+                end
+            when :false:
+                values.each do |v|
+                    return false if v
+                end
+            else # Just delegate everything else to facter
+                result = Facter.send(check).to_s.downcase.intern
+
+                found = values.find do |v|
+                    result == v.to_s.downcase.intern
+                end
+                return false unless found
+            end
+        end
+
+        return true
+    end
+
+    def command(name)
+        self.class.command(name)
+    end
+
+    def initialize(model)
+        @model = model
+    end
+
+    def name
+        @model.name
+    end
+
+    def to_s
+        "%s(provider=%s)" % [@model.to_s, self.class.name]
+    end
+end
+
+# $Id$