[MNG-8685] Better support for CI systems

api/maven-api-cli/src/main/java/org/apache/maven/api/cli/InvokerRequest.java

@@ -28,6 +28,7 @@
 import org.apache.maven.api.annotations.Experimental;
 import org.apache.maven.api.annotations.Immutable;
 import org.apache.maven.api.annotations.Nonnull;
+import org.apache.maven.api.cli.cisupport.CISupport;
 import org.apache.maven.api.services.Lookup;
 import org.apache.maven.api.services.MessageBuilderFactory;
 
@@ -182,11 +183,30 @@ default Optional<OutputStream> stdErr() {
     @Nonnull
     Optional<List<CoreExtensions>> coreExtensions();
 
+    /**
+     * Returns detected CI system, if any.
+     *
+     * @return an {@link Optional} containing the {@link CISupport} collected from CI system. or empty if CI not
+     * detected.
+     */
+    @Nonnull
+    Optional<CISupport> ciSupport();
+
     /**
      * Returns the options associated with this invocation request.
      *
      * @return the options object
      */
     @Nonnull
     Options options();
+
+    /**
+     * This method returns "verbose" option value derived from multiple places: CLI options, but also CI detection,
+     * if applicable.
+     */
+    default boolean effectiveVerbose() {
+        return options()
+                .verbose()
+                .orElse(ciSupport().isPresent() && ciSupport().get().isDebug());
+    }
 }

api/maven-api-cli/src/main/java/org/apache/maven/api/cli/cisupport/CISupport.java

@@ -0,0 +1,47 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.api.cli.cisupport;
+
+import org.apache.maven.api.annotations.Nonnull;
+
+/**
+ * CI support: this class contains gathered information and more from CI that Maven process runs on.
+ */
+public interface CISupport {
+    /**
+     * Short distinct name of CI system: "GH", "Jenkins", etc.
+     */
+    @Nonnull
+    String name();
+
+    /**
+     * May return a message that will be logged by Maven explaining why it was detected (and possibly more).
+     */
+    @Nonnull
+    default String message() {
+        return "";
+    }
+
+    /**
+     * Some CI systems may allow running jobs in "debug" (or some equivalent) mode.
+     */
+    default boolean isDebug() {
+        return false;
+    }
+}

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/BaseInvokerRequest.java

@@ -28,6 +28,7 @@
 import org.apache.maven.api.cli.CoreExtensions;
 import org.apache.maven.api.cli.InvokerRequest;
 import org.apache.maven.api.cli.ParserRequest;
+import org.apache.maven.api.cli.cisupport.CISupport;
 
 import static java.util.Objects.requireNonNull;
 
@@ -42,6 +43,7 @@ public abstract class BaseInvokerRequest implements InvokerRequest {
     private final Path topDirectory;
     private final Path rootDirectory;
     private final List<CoreExtensions> coreExtensions;
+    private final CISupport ciSupport;
 
     @SuppressWarnings("ParameterNumber")
     public BaseInvokerRequest(
@@ -54,7 +56,8 @@ public BaseInvokerRequest(
             @Nonnull Map<String, String> systemProperties,
             @Nonnull Path topDirectory,
             @Nullable Path rootDirectory,
-            @Nullable List<CoreExtensions> coreExtensions) {
+            @Nullable List<CoreExtensions> coreExtensions,
+            @Nullable CISupport ciSupport) {
         this.parserRequest = requireNonNull(parserRequest);
         this.parsingFailed = parsingFailed;
         this.cwd = requireNonNull(cwd);
@@ -66,6 +69,7 @@ public BaseInvokerRequest(
         this.topDirectory = requireNonNull(topDirectory);
         this.rootDirectory = rootDirectory;
         this.coreExtensions = coreExtensions;
+        this.ciSupport = ciSupport;
     }
 
     @Override
@@ -117,4 +121,9 @@ public Optional<Path> rootDirectory() {
     public Optional<List<CoreExtensions>> coreExtensions() {
         return Optional.ofNullable(coreExtensions);
     }
+
+    @Override
+    public Optional<CISupport> ciSupport() {
+        return Optional.ofNullable(ciSupport);
+    }
 }

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/BaseParser.java

@@ -43,11 +43,13 @@
 import org.apache.maven.api.cli.Options;
 import org.apache.maven.api.cli.Parser;
 import org.apache.maven.api.cli.ParserRequest;
+import org.apache.maven.api.cli.cisupport.CISupport;
 import org.apache.maven.api.cli.extensions.CoreExtension;
 import org.apache.maven.api.cli.extensions.InputLocation;
 import org.apache.maven.api.cli.extensions.InputSource;
 import org.apache.maven.api.services.Interpolator;
 import org.apache.maven.cling.internal.extension.io.CoreExtensionsStaxReader;
+import org.apache.maven.cling.invoker.cisupport.CIDetectorHelper;
 import org.apache.maven.cling.props.MavenPropertiesLoader;
 import org.apache.maven.cling.utils.CLIReportingUtils;
 import org.apache.maven.properties.internal.EnvironmentUtils;
@@ -86,6 +88,9 @@ public LocalContext(ParserRequest parserRequest) {
         @Nullable
         public List<CoreExtensions> extensions;
 
+        @Nullable
+        public CISupport ciSupport;
+
         public Options options;
 
         public Map<String, String> extraInterpolationSource() {
@@ -190,6 +195,9 @@ public InvokerRequest parseInvocation(ParserRequest parserRequest) {
             parserRequest.logger().error("Error reading core extensions descriptor", e);
         }
 
+        // CI detection
+        context.ciSupport = detectCI(context);
+
         // only if not failed so far; otherwise we may have no options to validate
         if (!context.parsingFailed) {
             validate(context);
@@ -500,4 +508,19 @@ protected List<CoreExtension> validateCoreExtensionsDescriptorFromFile(
                                         .collect(Collectors.joining(", ")))
                         .collect(Collectors.joining("; ")));
     }
+
+    @Nullable
+    protected CISupport detectCI(LocalContext context) {
+        List<CISupport> detected = CIDetectorHelper.detectCI();
+        if (detected.isEmpty()) {
+            return null;
+        } else if (detected.size() > 1) {
+            // warn
+            context.parserRequest
+                    .logger()
+                    .warn("Multiple CI systems detected:"
+                            + detected.stream().map(CISupport::name).collect(Collectors.joining(", ")));
+        }
+        return detected.get(0);
+    }
 }

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/LookupInvoker.java

@@ -46,6 +46,7 @@
 import org.apache.maven.api.cli.InvokerRequest;
 import org.apache.maven.api.cli.Logger;
 import org.apache.maven.api.cli.Options;
+import org.apache.maven.api.cli.cisupport.CISupport;
 import org.apache.maven.api.cli.logging.AccumulatingLogger;
 import org.apache.maven.api.services.BuilderProblem;
 import org.apache.maven.api.services.Interpolator;
@@ -278,7 +279,7 @@ protected void configureLogging(C context) throws Exception {
         context.slf4jConfiguration = Slf4jConfigurationFactory.getConfiguration(context.loggerFactory);
 
         context.loggerLevel = Slf4jConfiguration.Level.INFO;
-        if (mavenOptions.verbose().orElse(false)) {
+        if (context.invokerRequest.effectiveVerbose()) {
             context.loggerLevel = Slf4jConfiguration.Level.DEBUG;
         } else if (mavenOptions.quiet().orElse(false)) {
             context.loggerLevel = Slf4jConfiguration.Level.ERROR;
@@ -465,7 +466,7 @@ protected void showVersion(C context) {
         InvokerRequest invokerRequest = context.invokerRequest;
         if (invokerRequest.options().quiet().orElse(false)) {
             writer.accept(CLIReportingUtils.showVersionMinimal());
-        } else if (invokerRequest.options().verbose().orElse(false)) {
+        } else if (context.invokerRequest.effectiveVerbose()) {
             writer.accept(CLIReportingUtils.showVersion(
                     ProcessHandle.current().info().commandLine().orElse(null), describe(context.terminal)));
 
@@ -493,9 +494,8 @@ protected String describe(Terminal terminal) {
     }
 
     protected void preCommands(C context) throws Exception {
-        Options mavenOptions = context.invokerRequest.options();
-        boolean verbose = mavenOptions.verbose().orElse(false);
-        boolean version = mavenOptions.showVersion().orElse(false);
+        boolean verbose = context.invokerRequest.effectiveVerbose();
+        boolean version = context.invokerRequest.options().showVersion().orElse(false);
         if (verbose || version) {
             showVersion(context);
         }
@@ -726,11 +726,11 @@ protected boolean mayDisableInteractiveMode(C context, boolean proposedInteracti
             if (context.invokerRequest.options().nonInteractive().orElse(false)) {
                 return false;
             } else {
-                boolean runningOnCI = isRunningOnCI(context);
-                if (runningOnCI) {
+                if (context.invokerRequest.ciSupport().isPresent()) {
+                    CISupport ci = context.invokerRequest.ciSupport().get();
                     context.logger.info(
-                            "Making this build non-interactive, because the environment variable CI equals \"true\"."
-                                    + " Disable this detection by removing that variable or adding --force-interactive.");
+                            "Making this build non-interactive, because CI detected. Disable this detection by adding --force-interactive.");
+                    context.logger.info("Detected CI system: '" + ci.name() + "': " + ci.message());
                     return false;
                 }
             }
@@ -935,10 +935,5 @@ protected int calculateDegreeOfConcurrency(String threadConfiguration) {
         }
     }
 
-    protected boolean isRunningOnCI(C context) {
-        String ciEnv = context.protoSession.getSystemProperties().get("env.CI");
-        return ciEnv != null && !"false".equals(ciEnv);
-    }
-
     protected abstract int execute(C context) throws Exception;
 }

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/cisupport/CIDetector.java

@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.cling.invoker.cisupport;
+
+import java.util.Optional;
+
+import org.apache.maven.api.cli.cisupport.CISupport;
+
+/**
+ * Service interface to detect CI system process runs on, if any.
+ */
+public interface CIDetector {
+    /**
+     * Returns non-empty optional with CI information, if CI is detected, empty otherwise.
+     */
+    Optional<CISupport> detectCI();
+}

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/cisupport/CIDetectorHelper.java

@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.cling.invoker.cisupport;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+import java.util.ServiceLoader;
+
+import org.apache.maven.api.cli.cisupport.CISupport;
+
+/**
+ * CI detector helper: it uses service discovery (one is always present: {@link GenericCIDetector}) to detect CI, if
+ * present and returns a list of detections. If result has 2 or more results, it will return the generic result before.
+ */
+public final class CIDetectorHelper {
+    private CIDetectorHelper() {}
+
+    public static List<CISupport> detectCI() {
+        List<CIDetector> detectors = ServiceLoader.load(CIDetector.class).stream()
+                .map(ServiceLoader.Provider::get)
+                .toList();
+
+        ArrayList<CISupport> result = new ArrayList<>();
+        for (CIDetector detector : detectors) {
+            Optional<CISupport> detected = detector.detectCI();
+            detected.ifPresent(result::add);
+        }
+        if (result.size() > 1) {
+            // remove generic
+            result.removeIf(c -> GenericCIDetector.NAME.equals(c.name()));
+        }
+        return result;
+    }
+}

impl/maven-cli/src/main/java/org/apache/maven/cling/invoker/cisupport/GenericCIDetector.java

@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.cling.invoker.cisupport;
+
+import java.util.Optional;
+
+import org.apache.maven.api.cli.cisupport.CISupport;
+
+/**
+ * Generic CI support. This offers same support as Maven 3 always had. Is also special, as code will reject this
+ * detector result IF there are also any other returned via discovered services.
+ */
+public class GenericCIDetector implements CIDetector {
+    public static final String NAME = "generic";
+
+    @Override
+    public Optional<CISupport> detectCI() {
+        String ciEnv = System.getenv("CI");
+        if (ciEnv != null && !"false".equals(ciEnv)) {
+            return Optional.of(new CISupport() {
+                @Override
+                public String name() {
+                    return NAME;
+                }
+
+                @Override
+                public String message() {
+                    return "Environment variable CI equals \"true\". Disable detection by removing that variable or by setting it to any other value";
+                }
+            });
+        }
+        return Optional.empty();
+    }
+}