Add Json verifier

This patch adds Json verifier to the list of built-in verifiers. Json verifier
can be used with symbol ':json' on `file` like resources such as `file`,
`template` etc.

Signed-off-by: Antony Deepak Thomas <antonydeepak@gmail.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/spec/unit/resource/file/verification/json_spec.rb b/spec/unit/resource/file/verification/json_spec.rb
new file mode 100644
index 0000000000..22a769054d
--- /dev/null
+++ b/spec/unit/resource/file/verification/json_spec.rb
@@ -0,0 +1,66 @@
+#
+# Author:: Antony Thomas (<antonydeepak@gmail.com>)
+# Copyright:: Copyright (c) Chef Software Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require "spec_helper"
+
+describe Chef::Resource::File::Verification::Json do
+  let(:parent_resource) { Chef::Resource.new("llama") }
+
+  before(:all) do
+    @valid_json = "valid-#{Time.now.to_i}.json"
+    f = File.new(@valid_json, "w")
+    f.write('{
+      "foo": "bar"
+    }')
+    f.close
+
+    @invalid_json = "invalid-#{Time.now.to_i}.json"
+    f = File.new(@invalid_json, "w")
+    f.write("{
+      'foo': 'bar'
+    }")
+    f.close
+
+    @empty_json = "empty-#{Time.now.to_i}.json"
+    File.new(@empty_json, "w").close
+  end
+
+  context "verify" do
+    it "returns true for valid json" do
+      v = Chef::Resource::File::Verification::Json.new(parent_resource, :json, {})
+      expect(v.verify(@valid_json)).to eq(true)
+    end
+
+    it "returns false for invalid json" do
+      v = Chef::Resource::File::Verification::Json.new(parent_resource, :json, {})
+      expect(v.verify(@invalid_json)).to eq(false)
+    end
+
+    it "returns false for empty file" do
+      # empty string is invalid per JSON spec https://stackoverflow.com/questions/30621802/why-does-json-parse-fail-with-the-empty-string
+      v = Chef::Resource::File::Verification::Json.new(parent_resource, :json, {})
+      expect(v.verify(@empty_json)).to eq(false)
+    end
+  end
+
+  after(:all) do
+    File.delete(@valid_json)
+    File.delete(@invalid_json)
+    File.delete(@empty_json)
+  end
+end