[#5] Improve error handling on POST

Also covered by tests.

src/main/groovy/io/codearte/gradle/nexus/infra/NexusHttpResponseException.groovy

@@ -0,0 +1,22 @@
+package io.codearte.gradle.nexus.infra
+
+import groovy.transform.CompileStatic
+
+/**
+ * Custom exception to propagate server errors.
+ *
+ * Created as groovyx.net.http.HttpResponseException contains in a message only a reason phrase (e.g. Server Error) without response body
+ * which in many cases is crucial to determine the resons why error was returned.
+ *
+ * It may be made redundant once migrated to other HTTP library.
+ */
+@CompileStatic
+class NexusHttpResponseException extends NexusStagingException {
+
+    final int statusCode
+
+    NexusHttpResponseException(int statusCode, String message, Throwable cause) {
+        super(message, cause)
+        this.statusCode = statusCode
+    }
+}

src/main/groovy/io/codearte/gradle/nexus/infra/SimplifiedHttpJsonRestClient.groovy

@@ -1,11 +1,10 @@
 package io.codearte.gradle.nexus.infra
 
-import org.apache.http.client.HttpResponseException;
-
 import groovy.transform.CompileStatic
 import groovy.util.logging.Slf4j
 import groovyx.net.http.ContentType
 import groovyx.net.http.HttpResponseDecorator
+import groovyx.net.http.HttpResponseException
 import groovyx.net.http.RESTClient
 
 /**
@@ -52,19 +51,17 @@ class SimplifiedHttpJsonRestClient {
         setUriAndAuthentication(uri)
         Map params = createAndInitializeCallParametersMap()
         params.body = content
-        log.debug("POST request content: $content")
-		try {
-			//TODO: Add better error handling (e.g. display error message received from server, not only 500 + not fail on 404 in 'text/html')
-			HttpResponseDecorator response = (HttpResponseDecorator)restClient.post(params)
-			log.warn("POST response data: ${response.data}")
-		} catch(groovyx.net.http.HttpResponseException e) {
-		    //Apache' HttpResponseException ONLY puts the 2nd param in the e.getMessage which will be printed so
-		    //put all information there (status code, error str, body of response in case they put more error information there)
-
-			HttpResponseDecorator resp = e.getResponse();
-			String message = "${resp.statusLine.statusCode}:${resp.statusLine.reasonPhrase}  body=${resp.data}"
-		    log.error("POST response failed.  ${message}")
-			throw new HttpResponseException(e.getStatusCode(), message)
-		}
+        try {
+            log.debug("POST request content: $content")
+            HttpResponseDecorator response = (HttpResponseDecorator) restClient.post(params)
+            log.debug("POST response status ${response.status}, data: ${response.data}")
+        } catch (HttpResponseException e) {
+            //Enhance rethrown exception to contain also response body - #5
+            //TODO: Still better handle response content type on 404 and 50x - server returns 'text/plain', but RESTClient from Groovy Builder tries to parse it as JSON
+            HttpResponseDecorator resp = e.getResponse();
+            String message = "${resp.statusLine.statusCode}: ${resp.statusLine.reasonPhrase}, body: ${resp.data}"
+            log.warn("POST response failed. ${message}")
+            throw new NexusHttpResponseException(e.getStatusCode(), message, e)
+        }
     }
 }

src/test/groovy/io/codearte/gradle/nexus/functional/MockedResponseErrorHandlingSpec.groovy

@@ -0,0 +1,66 @@
+package io.codearte.gradle.nexus.functional
+
+import com.github.tomakehurst.wiremock.junit.WireMockRule
+import groovy.transform.NotYetImplemented
+import groovyx.net.http.HttpResponseException
+import groovyx.net.http.RESTClient
+import io.codearte.gradle.nexus.infra.NexusHttpResponseException
+import io.codearte.gradle.nexus.infra.SimplifiedHttpJsonRestClient
+import io.codearte.gradle.nexus.logic.RepositoryCloser
+import org.junit.Rule
+import spock.lang.Specification
+
+import static com.github.tomakehurst.wiremock.client.WireMock.aResponse
+import static com.github.tomakehurst.wiremock.client.WireMock.containing
+import static com.github.tomakehurst.wiremock.client.WireMock.equalTo
+import static com.github.tomakehurst.wiremock.client.WireMock.post
+import static com.github.tomakehurst.wiremock.client.WireMock.stubFor
+import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo
+
+class MockedResponseErrorHandlingSpec extends Specification {
+
+    private static final String TEST_MOCKED_USERNAME = ''
+    private static final String TEST_MOCKED_PASSWORD = ''
+    private static final String TEST_MOCKED_STAGING_PROFILE_ID = "93c08fdebde1ff"
+    private static final String TEST_MOCKED_NOT_EXISTING_REPOSITORY_ID = "xxx"
+    private static final String TEST_MOCKED_SERVER_ERROR_JSON_RESPONSE = """
+                        {
+                            "errors": [
+                                {
+                                    "id": "*",
+                                    "msg": "Unhandled: Missing staging repository: $TEST_MOCKED_NOT_EXISTING_REPOSITORY_ID"
+                                }
+                            ]
+                        }
+                        """.stripIndent()
+
+    @Rule
+    public WireMockRule wireMockRule = new WireMockRule(8089)
+
+    //Using private Options as server is not started yet
+    private String mockedUrl = "http://localhost:${wireMockRule.options.portNumber()}/"
+
+    def "should present response body on 500 server error"() {
+        given:
+            SimplifiedHttpJsonRestClient client = new SimplifiedHttpJsonRestClient(new RESTClient(), TEST_MOCKED_USERNAME, TEST_MOCKED_PASSWORD)
+            RepositoryCloser closer = new RepositoryCloser(client, mockedUrl)
+        and:
+            stubFor(post(urlEqualTo("/staging/profiles/$TEST_MOCKED_STAGING_PROFILE_ID/finish"))
+                    .withHeader("Content-Type", equalTo("application/json"))
+                    .withHeader("Accept", containing("application/json"))
+                    .willReturn(aResponse()
+                    .withStatus(500)
+                    .withBody(TEST_MOCKED_SERVER_ERROR_JSON_RESPONSE)
+                    .withHeader("Content-Type", "application/json")))
+        when:
+            closer.closeRepositoryWithIdAndStagingProfileId(TEST_MOCKED_NOT_EXISTING_REPOSITORY_ID, TEST_MOCKED_STAGING_PROFILE_ID)
+        then:
+            NexusHttpResponseException e = thrown()
+            e.statusCode == 500
+            e.message.contains("Missing staging repository: $TEST_MOCKED_NOT_EXISTING_REPOSITORY_ID")
+            e.cause instanceof HttpResponseException
+    }
+
+    @NotYetImplemented
+    def "should present response body on 400 or 500 errors with plain text response"() {}
+}