Verify installed Version matches expected Version and improve Error Messages

src/main/java/com/linkedplanet/maven/plugin/upm/AbstractUpmMojo.java

@@ -35,6 +35,7 @@
 
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 
 abstract class AbstractUpmMojo extends AbstractMojo {
@@ -72,31 +73,42 @@ BasicHeader getAuthHeader() {
                 "Basic " + Base64.encodeBase64String((username + ":" + password).getBytes(StandardCharsets.UTF_8)));
     }
 
-    void poll(String taskName, long maxWaitMillis, Supplier<Boolean> callback) throws Exception {
+    Boolean poll(String taskName, long maxWaitMillis, Supplier<Boolean> task) {
+        return poll(taskName, maxWaitMillis, task, result -> result);
+    }
+
+    Result pollResult(String taskName, long maxWaitMillis, Supplier<Result> task) {
+        return poll(taskName, maxWaitMillis, task, Result::isSuccess);
+    }
+
+    <T> T poll(String taskName, long maxWaitMillis, Supplier<T> task, Predicate<T> isCompleted) {
         long millisWaited = 0;
-        boolean success = false;
-        while (!success && millisWaited < maxWaitMillis) {
+        T taskResult = null;
+        while (millisWaited < maxWaitMillis) {
             getLog().info(taskName + ": Waiting for success (" + millisWaited + "/" + maxWaitMillis + " millis waited) ...");
             long beginWaitMillis = System.currentTimeMillis();
-            success = callback.get();
-            Thread.sleep(5000);
+            taskResult = task.get();
+            if (isCompleted.test(taskResult)) {
+                return taskResult;
+            }
+            try {
+                Thread.sleep(5000);
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                throw new RuntimeException(e);
+            }
             millisWaited += System.currentTimeMillis() - beginWaitMillis;
         }
-
-        if (millisWaited >= maxWaitMillis && !success) {
-            getLog().info(taskName + ": No longer waiting for success after " + maxWaitMillis + " millis");
-        }
-        if (success) {
-            getLog().info(taskName + ": Success");
-        }
+        getLog().info(taskName + ": No longer waiting for success after " + maxWaitMillis + " millis");
+        return taskResult;
     }
 
     static JsonObject parseResponseAsJsonObject(CloseableHttpResponse response) throws Exception {
         if (response.getStatusLine().getStatusCode() != 200) {
             throw new Exception(response.getStatusLine().toString());
         }
         String json = EntityUtils.toString(response.getEntity());
-        return new JsonParser().parse(json).getAsJsonObject();
+        return JsonParser.parseString(json).getAsJsonObject();
     }
 
 }

src/main/java/com/linkedplanet/maven/plugin/upm/Result.java

@@ -0,0 +1,49 @@
+package com.linkedplanet.maven.plugin.upm;
+
+interface Result {
+    String toMessage();
+
+    boolean isSuccess();
+
+    default boolean isFailure() {
+        return !isSuccess();
+    }
+
+    class Success implements Result {
+        @Override
+        public boolean isSuccess() {
+            return true;
+        }
+
+        @Override
+        public String toMessage() {
+            return "Plugin verification succeeded.";
+        }
+    }
+
+    class Failure implements Result {
+        private final String hint;
+        private final Throwable cause;
+
+        Failure(String hint, Throwable cause) {
+            this.hint = hint;
+            this.cause = cause;
+        }
+
+        Failure(String hint) {
+            this(hint, null);
+        }
+
+        @Override
+        public boolean isSuccess() {
+            return false;
+        }
+
+        @Override
+        public String toMessage() {
+            return cause == null
+                    ? hint
+                    : String.format("%s - Caused by: %s", hint, cause.getMessage());
+        }
+    }
+}

src/main/java/com/linkedplanet/maven/plugin/upm/UploadPluginFileMojo.java

@@ -33,6 +33,7 @@
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugins.annotations.Mojo;
 import org.apache.maven.plugins.annotations.Parameter;
+import org.apache.maven.project.MavenProject;
 
 import java.io.File;
 
@@ -44,6 +45,9 @@ public class UploadPluginFileMojo extends AbstractUpmMojo {
 
     private static final String REST_PATH_PLUGINS = "/rest/plugins/1.0";
 
+    @Parameter(defaultValue = "${project}", readonly = true, required = true)
+    private MavenProject project;
+
     @SuppressWarnings("unused")
     @Parameter(property = "pluginKey")
     private String pluginKey;
@@ -56,6 +60,7 @@ public class UploadPluginFileMojo extends AbstractUpmMojo {
     @Parameter(property = "waitForSuccessMillis", defaultValue = "60000")
     private int waitForSuccessMillis;
 
+
     @Override
     public void execute() throws MojoExecutionException {
         try (CloseableHttpClient httpClient = createHttpClient()) {
@@ -64,18 +69,20 @@ public void execute() throws MojoExecutionException {
             getLog().info("UPM token: " + token);
 
             getLog().info("Uploading file: " + pluginFile + " ...");
-            uploadFile(httpClient, token);
+            uploadPluginFile(httpClient, token);
 
             // wait for 5 seconds before checking plugin enabled state
             Thread.sleep(5000);
-            poll("Plugin installation", waitForSuccessMillis, () -> checkPluginEnabled(httpClient));
-
-
+            Result result = pollResult("Plugin installation", waitForSuccessMillis, () -> verifyInstalledVersion(httpClient));
+            if (result.isFailure()) {
+                throw new RuntimeException("The given plugin wasn't installed properly. Reason: " + result.toMessage());
+            }
         } catch (Exception e) {
             throw new MojoExecutionException("Plugin installation error", e);
         }
     }
 
+
     private String getUpmToken(CloseableHttpClient httpClient) throws Exception {
         String url = baseUrl.toString() + REST_PATH_PLUGINS + "/?os_authType=basic";
         HttpHead request = new HttpHead(url);
@@ -92,7 +99,7 @@ private String getUpmToken(CloseableHttpClient httpClient) throws Exception {
         }
     }
 
-    private void uploadFile(CloseableHttpClient httpClient, String token) throws Exception {
+    private void uploadPluginFile(CloseableHttpClient httpClient, String token) throws Exception {
         String url = baseUrl.toString() + REST_PATH_PLUGINS + "/?token=" + token;
         HttpPost request = new HttpPost(url);
         request.setHeader(getAuthHeader());
@@ -107,16 +114,27 @@ private void uploadFile(CloseableHttpClient httpClient, String token) throws Exc
         }
     }
 
-    private boolean checkPluginEnabled(CloseableHttpClient httpClient) {
+    private Result verifyInstalledVersion(CloseableHttpClient httpClient) {
+        String expectedVersion = project.getVersion();
         HttpGet request = new HttpGet(baseUrl.toString() + REST_PATH_PLUGINS + '/' + pluginKey + "-key");
         request.setHeader(getAuthHeader());
         try (CloseableHttpResponse response = httpClient.execute(request)) {
-            JsonObject jsonObject = parseResponseAsJsonObject(response);
-            return jsonObject.getAsJsonPrimitive("enabled").getAsBoolean();
-
+            JsonObject pluginInfo = parseResponseAsJsonObject(response);
+            String installedVersion = pluginInfo.getAsJsonPrimitive("version").getAsString();
+            boolean enabled = pluginInfo.getAsJsonPrimitive("enabled").getAsBoolean();
+            if (!enabled) {
+                return new Result.Failure("The plugin is not enabled. Please check the log for installation errors.");
+            }
+            if (!installedVersion.equals(expectedVersion)) {
+                return new Result.Failure(String.format(
+                        "Expected version %s but currently installed version is %s. Deinstall the currently installed version and try again.",
+                        expectedVersion,
+                        installedVersion));
+            }
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            return new Result.Failure("Failed to fetch plugin metadata from the platform. Ensure Confluence is reachable and try again.", e);
         }
+        return new Result.Success();
     }
 
 }