Add validation to Metadata

exposes #valid? and #errors methods to check validity.

2 files changed, 66 insertions, 0 deletions

diff --git a/lib/chef/cookbook/metadata.rb b/lib/chef/cookbook/metadata.rb
index bd3a400e10..c1fe20e748 100644
--- a/lib/chef/cookbook/metadata.rb
+++ b/lib/chef/cookbook/metadata.rb
@@ -110,6 +110,8 @@ class Chef
         @groupings = Mash.new
         @recipes = Mash.new
         @version = Version.new("0.0.0")
+
+        @errors = []
       end
 
       def ==(other)
@@ -118,6 +120,32 @@ class Chef
         end
       end
 
+      # Whether this metadata is valid. In order to be valid, all required
+      # fields must be set. Chef's validation implementation checks the content
+      # of a given field when setting (and raises an error if the content does
+      # not meet the criteria), so the content of the fields is not considered
+      # when checking validity.
+      #
+      # === Returns
+      # valid<Boolean>:: Whether this metadata object is valid
+      def valid?
+        run_validation
+        @errors.empty?
+      end
+
+      # A list of validation errors for this metadata object. See #valid? for
+      # comments about the validation criteria.
+      #
+      # If there are any validation errors, one or more error strings will be
+      # returned. Otherwise an empty array is returned.
+      #
+      # === Returns
+      # error messages<Array>:: Whether this metadata object is valid
+      def errors
+        run_validation
+        @errors
+      end
+
       # Sets the cookbooks maintainer, or returns it.
       #
       # === Parameters
@@ -516,6 +544,12 @@ class Chef
 
     private
 
+      def run_validation
+        if name.nil?
+          @errors = ["The `name' attribute is required in cookbook metadata"]
+        end
+      end
+
       def new_args_format(caller_name, dep_name, version_constraints)
         if version_constraints.empty?
           ">= 0.0.0"
diff --git a/spec/unit/cookbook/metadata_spec.rb b/spec/unit/cookbook/metadata_spec.rb
index 0352c17350..e61c85b42b 100644
--- a/spec/unit/cookbook/metadata_spec.rb
+++ b/spec/unit/cookbook/metadata_spec.rb
@@ -142,6 +142,38 @@ describe Chef::Cookbook::Metadata do
 
   end
 
+  describe "validation" do
+
+    context "when no required fields are set" do
+
+      it "is not valid" do
+        metadata.should_not be_valid
+      end
+
+      it "has a list of validation errors" do
+        expected_errors = ["The `name' attribute is required in cookbook metadata"]
+        metadata.errors.should eq(expected_errors)
+      end
+
+    end
+
+    context "when all required fields are set" do
+      before do
+        metadata.name "a-valid-name"
+      end
+
+      it "is valid" do
+        metadata.should be_valid
+      end
+
+      it "has no validation errors" do
+        metadata.errors.should be_empty
+      end
+
+    end
+
+  end
+
   describe "adding a supported platform" do
     it "should support adding a supported platform with a single expression" do
       metadata.supports("ubuntu", ">= 8.04")