Make it easier to have a versioned factorytm/versioned_api

classes providing an API should include VersionedAPI, whilst the factory
class includes VersionedAPIFactory.

Signed-off-by: Thom May <thom@may.lt>

3 files changed, 220 insertions, 0 deletions

diff --git a/spec/unit/http/api_versions_spec.rb b/spec/unit/http/api_versions_spec.rb
new file mode 100644
index 0000000000..79c97a1b69
--- /dev/null
+++ b/spec/unit/http/api_versions_spec.rb
@@ -0,0 +1,69 @@
+#
+# Copyright:: Copyright 2017, 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::HTTP::APIVersions do
+  class TestVersionClient < Chef::HTTP
+    use Chef::HTTP::APIVersions
+  end
+
+  before do
+    Chef::ServerAPIVersions.instance.reset!
+  end
+
+  let(:method) { "GET" }
+  let(:url) { "http://dummy.com" }
+  let(:headers) { {} }
+  let(:data) { false }
+
+  let(:request) {}
+  let(:return_value) { "200" }
+
+  # Test Variables
+  let(:response_body) { "Thanks for checking in." }
+  let(:response_headers) do
+    {
+      "x-ops-server-api-version" => { "min_version" => 0, "max_version" => 2 },
+    }
+  end
+
+  let(:response) do
+    m = double("HttpResponse", :body => response_body)
+    allow(m).to receive(:key?).with("x-ops-server-api-version").and_return(true)
+    allow(m).to receive(:[]) do |key|
+      response_headers[key]
+    end
+
+    m
+  end
+
+  let(:middleware) do
+    client = TestVersionClient.new(url)
+    client.middlewares[0]
+  end
+
+  def run_api_version_handler
+    middleware.handle_request(method, url, headers, data)
+    middleware.handle_response(response, request, return_value)
+  end
+
+  it "correctly stores server api versions" do
+    run_api_version_handler
+    expect(Chef::ServerAPIVersions.instance.min_server_version).to eq(0)
+  end
+end
diff --git a/spec/unit/mixin/versioned_api_spec.rb b/spec/unit/mixin/versioned_api_spec.rb
new file mode 100644
index 0000000000..4f2418ca24
--- /dev/null
+++ b/spec/unit/mixin/versioned_api_spec.rb
@@ -0,0 +1,107 @@
+#
+# Copyright:: Copyright 2015-2017, 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"
+require "chef/mixin/versioned_api"
+
+describe Chef::Mixin::VersionedAPI do
+  let(:dummy_class) { Class.new { extend Chef::Mixin::VersionedAPI } }
+
+  it "allows a class to declare the minimum supported API version" do
+    dummy_class.minimum_api_version 3
+    expect(dummy_class.minimum_api_version).to eq(3)
+  end
+end
+
+describe Chef::Mixin::VersionedAPIFactory do
+  class V1Class; extend Chef::Mixin::VersionedAPI; minimum_api_version 1; end
+  class V2Class; extend Chef::Mixin::VersionedAPI; minimum_api_version 2; end
+  class V3Class; extend Chef::Mixin::VersionedAPI; minimum_api_version 3; end
+
+  let(:factory_class) { Class.new { extend Chef::Mixin::VersionedAPIFactory } }
+
+  before do
+    Chef::ServerAPIVersions.instance.reset!
+  end
+
+  describe "#add_versioned_api_class" do
+    it "adds a target class" do
+      factory_class.add_versioned_api_class V1Class
+      expect(factory_class.versioned_interfaces).to eq([V1Class])
+    end
+
+    it "can be called many times" do
+      factory_class.add_versioned_api_class V1Class
+      factory_class.add_versioned_api_class V2Class
+      expect(factory_class.versioned_interfaces).to eq([V1Class, V2Class])
+    end
+  end
+
+  describe "#versioned_api_class" do
+    describe "with no known versions" do
+      it "with one class it returns that class" do
+        factory_class.add_versioned_api_class V2Class
+        expect(factory_class.versioned_api_class.minimum_api_version).to eq(2)
+      end
+
+      it "with many classes it returns the highest minimum version" do
+        factory_class.add_versioned_api_class V1Class
+        factory_class.add_versioned_api_class V2Class
+        factory_class.add_versioned_api_class V3Class
+        expect(factory_class.versioned_api_class.minimum_api_version).to eq(3)
+      end
+    end
+
+    describe "with a known version" do
+      it "with one class it returns that class" do
+        Chef::ServerAPIVersions.instance.set_versions({ "min_version" => 0, "max_version" => 2 })
+        factory_class.add_versioned_api_class V2Class
+        expect(factory_class.versioned_api_class.minimum_api_version).to eq(2)
+      end
+
+      it "with a maximum version it returns the highest possible versioned class" do
+        Chef::ServerAPIVersions.instance.set_versions({ "min_version" => 0, "max_version" => 2 })
+        factory_class.add_versioned_api_class V1Class
+        factory_class.add_versioned_api_class V2Class
+        factory_class.add_versioned_api_class V3Class
+        expect(factory_class.versioned_api_class.minimum_api_version).to eq(2)
+      end
+    end
+
+    it "with no classes it returns nil" do
+      expect(factory_class.versioned_api_class).to be_nil
+    end
+  end
+
+  describe "#new" do
+    it "creates an instance of the versioned class" do
+      factory_class.add_versioned_api_class V2Class
+      expect { factory_class.new }.to_not raise_error
+      expect(factory_class.new.class).to eq(V2Class)
+    end
+  end
+
+  describe "#def_versioned_delegator" do
+    it "delegates the method to the correct class" do
+      factory_class.add_versioned_api_class V2Class
+      factory_class.def_versioned_delegator("test_method")
+      expect(V2Class).to receive(:test_method).with("test message").and_return(true)
+
+      factory_class.test_method("test message")
+    end
+  end
+end
diff --git a/spec/unit/server_api_versions_spec.rb b/spec/unit/server_api_versions_spec.rb
new file mode 100644
index 0000000000..43445eb825
--- /dev/null
+++ b/spec/unit/server_api_versions_spec.rb
@@ -0,0 +1,44 @@
+#
+# Copyright:: Copyright 2017, 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::ServerAPIVersions do
+  before do
+    Chef::ServerAPIVersions.instance.reset!
+  end
+
+  describe "#min_server_version" do
+    it "returns nil if no versions have been recorded" do
+      expect(Chef::ServerAPIVersions.instance.min_server_version).to be_nil
+    end
+    it "returns the correct value" do
+      Chef::ServerAPIVersions.instance.set_versions({ "min_version" => 0, "max_version" => 2 })
+      expect(Chef::ServerAPIVersions.instance.min_server_version).to eq(0)
+    end
+  end
+
+  describe "#max_server_version" do
+    it "returns nil if no versions have been recorded" do
+      expect(Chef::ServerAPIVersions.instance.max_server_version).to be_nil
+    end
+    it "returns the correct value" do
+      Chef::ServerAPIVersions.instance.set_versions({ "min_version" => 0, "max_version" => 2 })
+      expect(Chef::ServerAPIVersions.instance.max_server_version).to eq(2)
+    end
+  end
+end