feat: support deleting branch versions (removing a version from a bra…

…nch)

lib/pact_broker/api/resources/branch_version.rb

@@ -14,7 +14,7 @@ def content_types_accepted
         end
 
         def allowed_methods
-          ["GET", "PUT", "OPTIONS"]
+          ["GET", "PUT", "DELETE", "OPTIONS"]
         end
 
         def resource_exists?
@@ -25,6 +25,11 @@ def to_json
           decorator_class(:branch_version_decorator).new(branch_version).to_json(decorator_options)
         end
 
+        def delete_resource
+          branch_service.delete_branch_version(branch_version)
+          true
+        end
+
         def from_json
           already_existed = !!branch_version
           @branch_version = branch_service.find_or_create_branch_version(identifier_from_path)

lib/pact_broker/doc/views/index/pacticipant-branch-version.markdown

@@ -1,14 +1,25 @@
 # Pacticipant branch version
 
-Allowed methods: `GET`, `PUT`
+Allowed methods: `GET`, `PUT`, `DELETE`
 
 Path: `/pacticipants/{pacticipant}/branches/{branch}/versions/{version}`
 
 Get or add/create a pacticipant version for a branch.
 
-## Example
+## Create
+
+### Example
 
 Add a version to a branch. The pacticipant and branch are automatically created if they do not exist.
 
     curl -XPUT http://broker/pacticipants/Bar/branches/main/versions/1e70030c6579915e5ff56b107a0fd25cf5df7464 \
           -H "Content-Type: application/json" -d "{}"
+
+
+## Delete
+
+Removes a pacticipant version from a branch. Does not delete the actual pacticipant version.
+
+Send a `DELETE` request to the branch version resource.
+
+    curl -XDELETE http://broker/pacticipants/Bar/branches/main/versions/1e70030c6579915e5ff56b107a0fd25cf5df7464

lib/pact_broker/versions/branch_service.rb

@@ -1,12 +1,19 @@
 require "pact_broker/logging"
 require "pact_broker/repositories"
 require "pact_broker/messages"
+require "forwardable"
 
 module PactBroker
   module Versions
     class BranchService
       extend PactBroker::Repositories
 
+      class << self
+        extend Forwardable
+        delegate [:delete_branch_version] => :branch_version_repository
+      end
+
+
       def self.find_branch_version(pacticipant_name:, branch_name:, version_number:, **)
         BranchVersion.where(
           version: PactBroker::Domain::Version.where_pacticipant_name_and_version_number(pacticipant_name, version_number),

lib/pact_broker/versions/branch_version_repository.rb

@@ -16,6 +16,12 @@ def add_branch(version, branch_name, auto_created: false)
         branch_version
       end
 
+      # Deletes a branch version - that is, removes a version from a branch.
+      # @param [PactBroker::Versions::BranchVersion] the branch version to delete
+      def delete_branch_version(branch_version)
+        branch_version.delete
+      end
+
       private
 
       def find_or_create_branch(pacticipant, branch_name)

spec/features/delete_branch_version_spec.rb

@@ -0,0 +1,30 @@
+describe "Deleting a branch version (removing a version from a branch)" do
+  before do
+    td.create_consumer("foo")
+      .create_consumer_version("1234", branch: "main")
+      .create_consumer_version("1234", branch: "not-main")
+      .create_consumer_version("555", branch: "main")
+      .create_consumer("bar")
+      .create_consumer_version("1234", branch: "main")
+  end
+
+  let(:path) { "/pacticipants/foo/branches/main/versions/1234" }
+  let(:headers) { { "CONTENT_TYPE" => "application/json" } }
+  let(:response_body) { JSON.parse(subject.body, symbolize_names: true) }
+
+  subject { delete(path, {}, headers) }
+
+  it "returns a 204 response" do
+    expect(subject.status).to be 204
+  end
+
+  it "deletes the branch version" do
+    expect { subject }.to change { PactBroker::Versions::BranchVersion.count }.by(-1)
+  end
+
+  context "when the branch version does not exist" do
+    let(:path) { "/pacticipants/foo/branches/main/versions/888" }
+
+    its(:status) { is_expected.to eq 404 }
+  end
+end