feat(describe-version): allow retrieving latest pacticipant version

doc/pacts/markdown/Pact Broker Client - Pact Broker.md

@@ -20,6 +20,10 @@
 
 * [A request for the compatibility matrix where only the version of Foo is specified](#a_request_for_the_compatibility_matrix_where_only_the_version_of_Foo_is_specified_given_the_pact_for_Foo_version_1.2.3_has_been_verified_by_Bar_version_4.5.6_and_version_5.6.7) given the pact for Foo version 1.2.3 has been verified by Bar version 4.5.6 and version 5.6.7
 
+* [A request for the index resource](#a_request_for_the_index_resource_given_the_pb:latest-tagged-version_relation_exists_in_the_index_resource) given the pb:latest-tagged-version relation exists in the index resource
+
+* [A request for the index resource](#a_request_for_the_index_resource_given_the_pb:latest-version_relation_exists_in_the_index_resource) given the pb:latest-version relation exists in the index resource
+
 * [A request for the list of the latest pacts from all consumers for the Pricing Service'](#a_request_for_the_list_of_the_latest_pacts_from_all_consumers_for_the_Pricing_Service'_given_a_latest_pact_between_Condor_and_the_Pricing_Service_exists) given a latest pact between Condor and the Pricing Service exists
 
 * [A request for the list of the latest prod pacts from all consumers for the Pricing Service'](#a_request_for_the_list_of_the_latest_prod_pacts_from_all_consumers_for_the_Pricing_Service'_given_tagged_as_prod_pact_between_Condor_and_the_Pricing_Service_exists) given tagged as prod pact between Condor and the Pricing Service exists
@@ -50,10 +54,14 @@
 
 * [A request to register the repository URL of a pacticipant](#a_request_to_register_the_repository_URL_of_a_pacticipant_given_the_'Pricing_Service'_does_not_exist_in_the_pact-broker) given the 'Pricing Service' does not exist in the pact-broker
 
+* [A request to retrieve the latest 'production' version of Condor](#a_request_to_retrieve_the_latest_'production'_version_of_Condor_given_'Condor'_exists_in_the_pact-broker_with_the_latest_tagged_'production'_version_1.2.3) given 'Condor' exists in the pact-broker with the latest tagged 'production' version 1.2.3
+
 * [A request to retrieve the latest pact between Condor and the Pricing Service](#a_request_to_retrieve_the_latest_pact_between_Condor_and_the_Pricing_Service_given_a_pact_between_Condor_and_the_Pricing_Service_exists) given a pact between Condor and the Pricing Service exists
 
 * [A request to retrieve the latest pact between Condor and the Pricing Service](#a_request_to_retrieve_the_latest_pact_between_Condor_and_the_Pricing_Service_given_no_pact_between_Condor_and_the_Pricing_Service_exists) given no pact between Condor and the Pricing Service exists
 
+* [A request to retrieve the latest version of Condor](#a_request_to_retrieve_the_latest_version_of_Condor_given_'Condor'_exists_in_the_pact-broker_with_the_latest_version_1.2.3) given 'Condor' exists in the pact-broker with the latest version 1.2.3
+
 * [A request to retrieve the pact between the production verison of Condor and the Pricing Service](#a_request_to_retrieve_the_pact_between_the_production_verison_of_Condor_and_the_Pricing_Service_given_a_pact_between_Condor_and_the_Pricing_Service_exists_for_the_production_version_of_Condor) given a pact between Condor and the Pricing Service exists for the production version of Condor
 
 * [A request to tag the production version of Condor](#a_request_to_tag_the_production_version_of_Condor_given_'Condor'_exists_in_the_pact-broker_with_version_1.3.0,_tagged_with_'prod') given 'Condor' exists in the pact-broker with version 1.3.0, tagged with 'prod'
@@ -418,6 +426,54 @@ Pact Broker will respond with:
   }
 }
 ```
+<a name="a_request_for_the_index_resource_given_the_pb:latest-tagged-version_relation_exists_in_the_index_resource"></a>
+Given **the pb:latest-tagged-version relation exists in the index resource**, upon receiving **a request for the index resource** from Pact Broker Client, with
+```json
+{
+  "method": "get",
+  "path": "/",
+  "headers": {
+    "Accept": "application/json, application/hal+json"
+  }
+}
+```
+Pact Broker will respond with:
+```json
+{
+  "status": 200,
+  "body": {
+    "_links": {
+      "pb:latest-tagged-version": {
+        "href": "http://localhost:1234/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-TAGGED-VERSION-{pacticipant}-{tag}"
+      }
+    }
+  }
+}
+```
+<a name="a_request_for_the_index_resource_given_the_pb:latest-version_relation_exists_in_the_index_resource"></a>
+Given **the pb:latest-version relation exists in the index resource**, upon receiving **a request for the index resource** from Pact Broker Client, with
+```json
+{
+  "method": "get",
+  "path": "/",
+  "headers": {
+    "Accept": "application/json, application/hal+json"
+  }
+}
+```
+Pact Broker will respond with:
+```json
+{
+  "status": 200,
+  "body": {
+    "_links": {
+      "pb:latest-version": {
+        "href": "http://localhost:1234/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-VERSION-{pacticipant}"
+      }
+    }
+  }
+}
+```
 <a name="a_request_for_the_list_of_the_latest_pacts_from_all_consumers_for_the_Pricing_Service&#39;_given_a_latest_pact_between_Condor_and_the_Pricing_Service_exists"></a>
 Given **a latest pact between Condor and the Pricing Service exists**, upon receiving **a request for the list of the latest pacts from all consumers for the Pricing Service'** from Pact Broker Client, with
 ```json
@@ -923,6 +979,31 @@ Pact Broker will respond with:
   "status": 201
 }
 ```
+<a name="a_request_to_retrieve_the_latest_&#39;production&#39;_version_of_Condor_given_&#39;Condor&#39;_exists_in_the_pact-broker_with_the_latest_tagged_&#39;production&#39;_version_1.2.3"></a>
+Given **'Condor' exists in the pact-broker with the latest tagged 'production' version 1.2.3**, upon receiving **a request to retrieve the latest 'production' version of Condor** from Pact Broker Client, with
+```json
+{
+  "method": "get",
+  "path": "/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-TAGGED-VERSION-Condor-production",
+  "headers": {
+    "Accept": "application/json, application/hal+json"
+  }
+}
+```
+Pact Broker will respond with:
+```json
+{
+  "status": 200,
+  "body": {
+    "number": "1.2.3",
+    "_links": {
+      "self": {
+        "href": "http://localhost:1234/some-url"
+      }
+    }
+  }
+}
+```
 <a name="a_request_to_retrieve_the_latest_pact_between_Condor_and_the_Pricing_Service_given_a_pact_between_Condor_and_the_Pricing_Service_exists"></a>
 Given **a pact between Condor and the Pricing Service exists**, upon receiving **a request to retrieve the latest pact between Condor and the Pricing Service** from Pact Broker Client, with
 ```json
@@ -966,6 +1047,31 @@ Pact Broker will respond with:
   "status": 404
 }
 ```
+<a name="a_request_to_retrieve_the_latest_version_of_Condor_given_&#39;Condor&#39;_exists_in_the_pact-broker_with_the_latest_version_1.2.3"></a>
+Given **'Condor' exists in the pact-broker with the latest version 1.2.3**, upon receiving **a request to retrieve the latest version of Condor** from Pact Broker Client, with
+```json
+{
+  "method": "get",
+  "path": "/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-VERSION-Condor",
+  "headers": {
+    "Accept": "application/json, application/hal+json"
+  }
+}
+```
+Pact Broker will respond with:
+```json
+{
+  "status": 200,
+  "body": {
+    "number": "1.2.3",
+    "_links": {
+      "self": {
+        "href": "http://localhost:1234/some-url"
+      }
+    }
+  }
+}
+```
 <a name="a_request_to_retrieve_the_pact_between_the_production_verison_of_Condor_and_the_Pricing_Service_given_a_pact_between_Condor_and_the_Pricing_Service_exists_for_the_production_version_of_Condor"></a>
 Given **a pact between Condor and the Pricing Service exists for the production version of Condor**, upon receiving **a request to retrieve the pact between the production verison of Condor and the Pricing Service** from Pact Broker Client, with
 ```json

lib/pact_broker/client/base_client.rb

@@ -63,7 +63,7 @@ def default_put_headers
 
       def handle_response response
         if response.success?
-          yield
+          yield response
         elsif response.code == 404
           nil
         elsif response.code == 401
@@ -98,6 +98,21 @@ def get url, *args
         self.class.get(url, *args)
       end
 
+      def url_for_relation relation_name, params
+        handle_response(get("/", headers: default_get_headers)) do | response |
+          relation = (JSON.parse(response.body)['_links'] || {})[relation_name]
+          if relation
+            url = relation['href']
+            params.each do | (key, value) |
+              url = url.gsub("{#{key}}", value)
+            end
+            url
+          else
+            raise PactBroker::Client::RelationNotFound.new("Could not find relation #{relation_name} in index resource. Try upgrading your Pact Broker as the feature you require may not exist in your version.")
+          end
+        end
+      end
+
       def verbose?
         @verbose
       end

lib/pact_broker/client/cli/broker.rb

@@ -89,7 +89,7 @@ def describe_version
             pacticipant: options.pacticipant,
             version: options.version,
             latest: latest,
-            tag: options.latest.is_a?(String) ? options.latest : nil
+            tag: options.latest != "latest" ? options.latest : nil
           }
           opts = {
             output: options.output

lib/pact_broker/client/error.rb

@@ -1,5 +1,7 @@
 module PactBroker
   module Client
     class Error < StandardError; end
+
+    class RelationNotFound < Error; end
   end
 end

lib/pact_broker/client/versions.rb

@@ -13,13 +13,15 @@ def find options
         end
       end
 
-      # TODO this is not a valid URL!
       def latest options
-        query = options[:tag] ? {tag: options[:tag]} : {}
-        response = self.class.get("#{versions_base_url(options)}/latest", query: query, headers: default_get_headers)
-
-        handle_response(response) do
-          string_keys_to_symbols(response.to_hash)
+        puts options
+        url = if options[:tag]
+          url_for_relation('pb:latest-tagged-version', pacticipant: options.fetch(:pacticipant), tag: options.fetch(:tag))
+        else
+          url_for_relation('pb:latest-version', pacticipant: options.fetch(:pacticipant))
+        end
+        handle_response(get(url, headers: default_get_headers)) do | response |
+          JSON.parse(response.body, symbolize_names: true)
         end
       end
 

lib/pact_broker/client/versions/describe.rb

@@ -32,7 +32,11 @@ def call
           else
             pact_broker_client.pacticipants.versions.latest(params)
           end
-          Result.new(true, format_version(version_hash))
+          if version_hash
+            Result.new(true, format_version(version_hash))
+          else
+            Result.new(false, "Pacticipant version not found")
+          end
         end
 
         private

spec/lib/pact_broker/client/base_client_spec.rb

@@ -3,6 +3,8 @@ module PactBroker
   module Client
     describe BaseClient do
       describe '#initialize' do
+        subject { BaseClient.new(base_url: base_url) }
+
         let(:base_url) { 'http://pact_broker_base_url'}
         let(:username) { 'pact_repo_username'}
         let(:password) { 'pact_repo_password'}
@@ -45,6 +47,32 @@ module Client
             subject
           end
         end
+
+        describe "url_for_relation" do
+          let(:index_body) do
+            {
+              _links: {
+                :'pb:foo-bar' => {
+                  href: "http://foo-bar/{name}"
+                }
+              }
+            }.to_json
+          end
+
+          let!(:request) do
+            stub_request(:get, "http://pact_broker_base_url/").to_return(status: 200, body: index_body, headers: { "Content-Type" => "application/json" }  )
+          end
+
+          it "retrieves a relation URL from the index" do
+            expect(subject.url_for_relation('pb:foo-bar', name: 'wiffle')).to eq 'http://foo-bar/wiffle'
+          end
+
+          context "when the relation is not found" do
+            it "raises an error" do
+              expect { subject.url_for_relation('pb:not-found', name: 'wiffle') }.to raise_error PactBroker::Client::RelationNotFound, /Could not find relation pb:not-found in index resource/
+            end
+          end
+        end
       end
     end
   end

spec/pacts/pact_broker_client-pact_broker.json

@@ -1090,6 +1090,124 @@
           }
         }
       }
+    },
+    {
+      "description": "a request for the index resource",
+      "providerState": "the pb:latest-version relation exists in the index resource",
+      "request": {
+        "method": "get",
+        "path": "/",
+        "headers": {
+          "Accept": "application/json, application/hal+json"
+        }
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+        },
+        "body": {
+          "_links": {
+            "pb:latest-version": {
+              "href": "http://localhost:1234/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-VERSION-{pacticipant}"
+            }
+          }
+        },
+        "matchingRules": {
+          "$.body._links.pb:latest-version.href": {
+            "match": "regex",
+            "regex": "http:\\/\\/.*{pacticipant}"
+          }
+        }
+      }
+    },
+    {
+      "description": "a request to retrieve the latest version of Condor",
+      "providerState": "'Condor' exists in the pact-broker with the latest version 1.2.3",
+      "request": {
+        "method": "get",
+        "path": "/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-VERSION-Condor",
+        "headers": {
+          "Accept": "application/json, application/hal+json"
+        }
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+        },
+        "body": {
+          "number": "1.2.3",
+          "_links": {
+            "self": {
+              "href": "http://localhost:1234/some-url"
+            }
+          }
+        },
+        "matchingRules": {
+          "$.body._links.self.href": {
+            "match": "regex",
+            "regex": "http:\\/\\/.*"
+          }
+        }
+      }
+    },
+    {
+      "description": "a request for the index resource",
+      "providerState": "the pb:latest-tagged-version relation exists in the index resource",
+      "request": {
+        "method": "get",
+        "path": "/",
+        "headers": {
+          "Accept": "application/json, application/hal+json"
+        }
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+        },
+        "body": {
+          "_links": {
+            "pb:latest-tagged-version": {
+              "href": "http://localhost:1234/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-TAGGED-VERSION-{pacticipant}-{tag}"
+            }
+          }
+        },
+        "matchingRules": {
+          "$.body._links.pb:latest-tagged-version.href": {
+            "match": "regex",
+            "regex": "http:\\/\\/.*{pacticipant}.*{tag}"
+          }
+        }
+      }
+    },
+    {
+      "description": "a request to retrieve the latest 'production' version of Condor",
+      "providerState": "'Condor' exists in the pact-broker with the latest tagged 'production' version 1.2.3",
+      "request": {
+        "method": "get",
+        "path": "/HAL-REL-PLACEHOLDER-INDEX-PB-LATEST-TAGGED-VERSION-Condor-production",
+        "headers": {
+          "Accept": "application/json, application/hal+json"
+        }
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+        },
+        "body": {
+          "number": "1.2.3",
+          "_links": {
+            "self": {
+              "href": "http://localhost:1234/some-url"
+            }
+          }
+        },
+        "matchingRules": {
+          "$.body._links.self.href": {
+            "match": "regex",
+            "regex": "http:\\/\\/.*"
+          }
+        }
+      }
     }
   ],
   "metadata": {