feat: add latest version for branch endpoint

lib/pact_broker/api.rb

@@ -97,6 +97,7 @@ def self.build_api(application_context = PactBroker::ApplicationContext.default_
         add ["pacticipants", :pacticipant_name, "versions", :pacticipant_version_number, "tags", :tag_name], Api::Resources::Tag, {resource_name: "pacticipant_version_tag"}
         add ["pacticipants", :pacticipant_name, "branches"], Api::Resources::PacticipantBranches, {resource_name: "pacticipant_branches"}
         add ["pacticipants", :pacticipant_name, "branches", :branch_name], Api::Resources::Branch, { resource_name: "branch" }
+        add ["pacticipants", :pacticipant_name, "branches", :branch_name, "latest-version"], Api::Resources::LatestVersion, { resource_name: "latest_pacticipant_version_for_branch" }
         add ["pacticipants", :pacticipant_name, "branches", :branch_name, "versions", :version_number], Api::Resources::BranchVersion, { resource_name: "branch_version" }
         add ["pacticipants", :pacticipant_name, "branches", :branch_name, "latest-version", "can-i-deploy", "to-environment", :environment_name], Api::Resources::CanIDeployPacticipantVersionByBranchToEnvironment, { resource_name: "can_i_deploy_latest_branch_version_to_environment" }
         add ["pacticipants", :pacticipant_name, "branches", :branch_name, "latest-version", "can-i-deploy", "to-environment", :environment_name, "badge"], Api::Resources::CanIDeployPacticipantVersionByBranchToEnvironmentBadge, { resource_name: "can_i_deploy_latest_branch_version_to_environment_badge" }

lib/pact_broker/api/decorators/branch_decorator.rb

@@ -18,7 +18,7 @@ class BranchDecorator < BaseDecorator
         link "pb:latest-version" do | user_options |
           {
             title: "Latest version for branch",
-            href: branch_versions_url(represented, user_options.fetch(:base_url)) + "?size=1"
+            href: latest_version_for_branch_url(represented, user_options.fetch(:base_url))
           }
         end
 

lib/pact_broker/api/decorators/version_decorator.rb

@@ -21,7 +21,7 @@ class VersionDecorator < BaseDecorator
           {
             title: "Version",
             name: represented.number,
-            href: version_url(options.fetch(:base_url), represented)
+            href: options.fetch(:resource_url)
           }
         end
 

lib/pact_broker/api/pact_broker_urls.rb

@@ -243,6 +243,10 @@ def branch_version_url(branch_version, base_url = "")
         "#{branch_versions_url(branch_version.branch, base_url)}/#{url_encode(branch_version.version_number)}"
       end
 
+      def latest_version_for_branch_url(branch, base_url = "")
+        "#{branch_url(branch, base_url)}/latest-version"
+      end
+
       def templated_tag_url_for_pacticipant pacticipant_name, base_url = ""
         pacticipant_url_from_params({ pacticipant_name: pacticipant_name }, base_url) + "/versions/{version}/tags/{tag}"
       end

lib/pact_broker/api/resources/latest_version.rb

@@ -17,6 +17,8 @@ def allowed_methods
         def version
           if identifier_from_path[:tag]
             @version ||= version_service.find_by_pacticipant_name_and_latest_tag(identifier_from_path[:pacticipant_name], identifier_from_path[:tag])
+          elsif identifier_from_path[:branch_name]
+            @version ||= version_service.find_latest_by_pacticipant_name_and_branch_name(identifier_from_path[:pacticipant_name], identifier_from_path[:branch_name])
           else
             @version ||= version_service.find_latest_by_pacticpant_name(identifier_from_path)
           end

spec/features/get_latest_version_for_branch_spec.rb

@@ -0,0 +1,18 @@
+describe "Get latest version for branch" do
+  before do
+    td.create_consumer("Foo")
+      .create_consumer_version("1", branch: "main")
+      .create_consumer_version("2", branch: "main")
+      .create_consumer_version("3", branch: "not-main")
+  end
+  let(:path) { PactBroker::Api::PactBrokerUrls.latest_version_for_branch_url(PactBroker::Versions::Branch.order(:id).first) }
+  let(:rack_env) { { "CONTENT_TYPE" => "application/json" } }
+
+  subject { get(path, {}, rack_env) }
+
+  it { is_expected.to be_a_hal_json_success_response }
+
+  it "returns the latest version for the branch" do
+    expect(JSON.parse(subject.body)["number"]).to eq "2"
+  end
+end

spec/fixtures/approvals/pacticipant_branches_decorator.approved.json

@@ -11,7 +11,7 @@
           },
           "pb:latest-version": {
             "title": "Latest version for branch",
-            "href": "http://example.org/pacticipants/Foo/branches/main/versions?size=1"
+            "href": "http://example.org/pacticipants/Foo/branches/main/latest-version"
           }
         }
       }

spec/lib/pact_broker/api/decorators/version_decorator_spec.rb

@@ -48,13 +48,13 @@ module Decorators
           end
 
           let(:base_url) { "http://example.org" }
-          let(:options) { { user_options: { base_url: base_url, environments: environments } } }
+          let(:options) { { user_options: { base_url: base_url, resource_url: "resource_url", environments: environments } } }
           let(:decorator) { VersionDecorator.new(version) }
 
           subject { JSON.parse(decorator.to_json(options), symbolize_names: true) }
 
           it "includes a link to itself" do
-            expect(subject[:_links][:self][:href]).to eq "http://example.org/pacticipants/Consumer/versions/1.2.3"
+            expect(subject[:_links][:self][:href]).to eq "resource_url"
           end
 
           it "includes the version number in the link" do
@@ -125,7 +125,7 @@ module Decorators
           end
 
           context "when the environments option is not present" do
-            let(:options) { { user_options: { base_url: base_url } } }
+            let(:options) { { user_options: { base_url: base_url, resource_url: "resource_url" } } }
 
             it "does not include the pb:record-deployment or pb:record-release" do
               expect(subject[:_links]).to_not have_key(:'pb:record-deployment')

spec/support/all_routes_spec_support.yml

@@ -40,6 +40,7 @@ requests_which_are_exected_to_have_no_policy_record:
   - pacticipant_label PUT
   - pacticipant_label DELETE
   - latest_pacticipant_version GET
+  - latest_pacticipant_version_for_branch GET
   - latest_tagged_pacticipant_version GET
   - can_i_deploy_latest_tagged_version_to_tag GET
   - can_i_deploy_latest_tagged_version_to_tag_badge GET