[MNG-8535] Full std stream support for executor

The std stream support was incomplete in maven-executor

---

https://issues.apache.org/jira/browse/MNG-8535

Author: cstamas

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

@@ -54,6 +54,15 @@ public interface InvokerRequest {
      */
     boolean parsingFailed();
 
+    /**
+     * Returns {@code true} if this call happens in "embedded" mode.
+     *
+     * @see ParserRequest#embedded()
+     */
+    default boolean embedded() {
+        return parserRequest().embedded();
+    }
+
     /**
      * Returns the current working directory for the Maven execution.
      * This is typically the directory from which Maven was invoked.
@@ -138,23 +147,29 @@ default Lookup lookup() {
      * @return an {@link Optional} containing the input stream, or empty if not applicable
      */
     @Nonnull
-    Optional<InputStream> in();
+    default Optional<InputStream> stdIn() {
+        return Optional.ofNullable(parserRequest().stdIn());
+    }
 
     /**
      * Returns the output stream for the Maven execution, if running in embedded mode.
      *
      * @return an {@link Optional} containing the output stream, or empty if not applicable
      */
     @Nonnull
-    Optional<OutputStream> out();
+    default Optional<OutputStream> stdOut() {
+        return Optional.ofNullable(parserRequest().stdOut());
+    }
 
     /**
      * Returns the error stream for the Maven execution, if running in embedded mode.
      *
      * @return an {@link Optional} containing the error stream, or empty if not applicable
      */
     @Nonnull
-    Optional<OutputStream> err();
+    default Optional<OutputStream> stdErr() {
+        return Optional.ofNullable(parserRequest().stdErr());
+    }
 
     /**
      * Returns a list of core extensions, if configured in the .mvn/extensions.xml file.

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

@@ -125,30 +125,37 @@ public interface ParserRequest {
 
     /**
      * Returns the input stream to be used for the Maven execution.
-     * If not set, System.in will be used by default.
+     * If not set, {@link System#in} will be used by default.
      *
      * @return the input stream, or null if not set
      */
     @Nullable
-    InputStream in();
+    InputStream stdIn();
 
     /**
      * Returns the output stream to be used for the Maven execution.
-     * If not set, System.out will be used by default.
+     * If not set, {@link System#out} will be used by default.
      *
      * @return the output stream, or null if not set
      */
     @Nullable
-    OutputStream out();
+    OutputStream stdOut();
 
     /**
      * Returns the error stream to be used for the Maven execution.
-     * If not set, System.err will be used by default.
+     * If not set, {@link System#err} will be used by default.
      *
      * @return the error stream, or null if not set
      */
     @Nullable
-    OutputStream err();
+    OutputStream stdErr();
+
+    /**
+     * Returns {@code true} if this call happens in "embedded" mode, for example by another application that
+     * embeds Maven. When running in "embedded" mode, Maven will not try to grab system terminal and will use
+     * provided {@link #stdIn()} or {@link InputStream#nullInputStream()} as standard in stream.
+     */
+    boolean embedded();
 
     /**
      * Creates a new Builder instance for constructing a Maven ParserRequest.
@@ -251,9 +258,10 @@ class Builder {
         private Path cwd;
         private Path mavenHome;
         private Path userHome;
-        private InputStream in;
-        private OutputStream out;
-        private OutputStream err;
+        private InputStream stdIn;
+        private OutputStream stdOut;
+        private OutputStream stdErr;
+        private boolean embedded = false;
 
         private Builder(
                 String command, String commandName, List<String> args, MessageBuilderFactory messageBuilderFactory) {
@@ -284,18 +292,23 @@ public Builder userHome(Path userHome) {
             return this;
         }
 
-        public Builder in(InputStream in) {
-            this.in = in;
+        public Builder stdIn(InputStream stdIn) {
+            this.stdIn = stdIn;
             return this;
         }
 
-        public Builder out(OutputStream out) {
-            this.out = out;
+        public Builder stdOut(OutputStream stdOut) {
+            this.stdOut = stdOut;
             return this;
         }
 
-        public Builder err(OutputStream err) {
-            this.err = err;
+        public Builder stdErr(OutputStream stdErr) {
+            this.stdErr = stdErr;
+            return this;
+        }
+
+        public Builder embedded(boolean embedded) {
+            this.embedded = embedded;
             return this;
         }
 
@@ -310,9 +323,10 @@ public ParserRequest build() {
                     cwd,
                     mavenHome,
                     userHome,
-                    in,
-                    out,
-                    err);
+                    stdIn,
+                    stdOut,
+                    stdErr,
+                    embedded);
         }
 
         @SuppressWarnings("ParameterNumber")
@@ -326,9 +340,10 @@ private static class ParserRequestImpl implements ParserRequest {
             private final Path cwd;
             private final Path mavenHome;
             private final Path userHome;
-            private final InputStream in;
-            private final OutputStream out;
-            private final OutputStream err;
+            private final InputStream stdIn;
+            private final OutputStream stdOut;
+            private final OutputStream stdErr;
+            private final boolean embedded;
 
             private ParserRequestImpl(
                     String command,
@@ -340,9 +355,10 @@ private ParserRequestImpl(
                     Path cwd,
                     Path mavenHome,
                     Path userHome,
-                    InputStream in,
-                    OutputStream out,
-                    OutputStream err) {
+                    InputStream stdIn,
+                    OutputStream stdOut,
+                    OutputStream stdErr,
+                    boolean embedded) {
                 this.command = requireNonNull(command, "command");
                 this.commandName = requireNonNull(commandName, "commandName");
                 this.args = List.copyOf(requireNonNull(args, "args"));
@@ -352,9 +368,10 @@ private ParserRequestImpl(
                 this.cwd = cwd;
                 this.mavenHome = mavenHome;
                 this.userHome = userHome;
-                this.in = in;
-                this.out = out;
-                this.err = err;
+                this.stdIn = stdIn;
+                this.stdOut = stdOut;
+                this.stdErr = stdErr;
+                this.embedded = embedded;
             }
 
             @Override
@@ -403,18 +420,23 @@ public Path userHome() {
             }
 
             @Override
-            public InputStream in() {
-                return in;
+            public InputStream stdIn() {
+                return stdIn;
+            }
+
+            @Override
+            public OutputStream stdOut() {
+                return stdOut;
             }
 
             @Override
-            public OutputStream out() {
-                return out;
+            public OutputStream stdErr() {
+                return stdErr;
             }
 
             @Override
-            public OutputStream err() {
-                return err;
+            public boolean embedded() {
+                return embedded;
             }
         }
 

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

@@ -19,11 +19,17 @@
 package org.apache.maven.cling;
 
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 
+import org.apache.maven.api.annotations.Nullable;
 import org.apache.maven.api.cli.Invoker;
 import org.apache.maven.api.cli.InvokerException;
-import org.apache.maven.api.cli.InvokerRequest;
+import org.apache.maven.api.cli.Parser;
+import org.apache.maven.api.cli.ParserRequest;
+import org.apache.maven.api.services.MessageBuilderFactory;
 import org.apache.maven.cling.invoker.logging.SystemLogger;
+import org.apache.maven.jline.JLineMessageBuilderFactory;
 import org.codehaus.plexus.classworlds.ClassWorld;
 
 import static java.util.Objects.requireNonNull;
@@ -59,14 +65,26 @@ private ClingSupport(ClassWorld classWorld, boolean classWorldManaged) {
     /**
      * The main entry point.
      */
-    public int run(String[] args) throws IOException {
+    public int run(
+            String[] args,
+            @Nullable InputStream stdIn,
+            @Nullable OutputStream stdOut,
+            @Nullable OutputStream stdErr,
+            boolean embedded)
+            throws IOException {
         try (Invoker invoker = createInvoker()) {
-            return invoker.invoke(parseArguments(args));
+            return invoker.invoke(createParser()
+                    .parseInvocation(createParserRequestBuilder(args)
+                            .stdIn(stdIn)
+                            .stdOut(stdOut)
+                            .stdErr(stdErr)
+                            .embedded(embedded)
+                            .build()));
         } catch (InvokerException.ExitException e) {
             return e.getExitCode();
         } catch (Exception e) {
             // last resort; as ideally we should get ExitException only
-            new SystemLogger().error(e.getMessage(), e);
+            new SystemLogger(stdErr).error(e.getMessage(), e);
             return 1;
         } finally {
             if (classWorldManaged) {
@@ -75,7 +93,13 @@ public int run(String[] args) throws IOException {
         }
     }
 
+    protected MessageBuilderFactory createMessageBuilderFactory() {
+        return new JLineMessageBuilderFactory();
+    }
+
     protected abstract Invoker createInvoker();
 
-    protected abstract InvokerRequest parseArguments(String[] args);
+    protected abstract Parser createParser();
+
+    protected abstract ParserRequest.Builder createParserRequestBuilder(String[] args);
 }

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

@@ -19,14 +19,16 @@
 package org.apache.maven.cling;
 
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 
+import org.apache.maven.api.annotations.Nullable;
 import org.apache.maven.api.cli.Invoker;
-import org.apache.maven.api.cli.InvokerRequest;
+import org.apache.maven.api.cli.Parser;
 import org.apache.maven.api.cli.ParserRequest;
 import org.apache.maven.cling.invoker.ProtoLookup;
 import org.apache.maven.cling.invoker.mvn.MavenInvoker;
 import org.apache.maven.cling.invoker.mvn.MavenParser;
-import org.apache.maven.jline.JLineMessageBuilderFactory;
 import org.codehaus.plexus.classworlds.ClassWorld;
 
 /**
@@ -38,15 +40,28 @@ public class MavenCling extends ClingSupport {
      * circumstances.
      */
     public static void main(String[] args) throws IOException {
-        int exitCode = new MavenCling().run(args);
+        int exitCode = new MavenCling().run(args, null, null, null, false);
         System.exit(exitCode);
     }
 
     /**
      * ClassWorld Launcher "enhanced" entry point: returning exitCode and accepts Class World.
      */
     public static int main(String[] args, ClassWorld world) throws IOException {
-        return new MavenCling(world).run(args);
+        return new MavenCling(world).run(args, null, null, null, false);
+    }
+
+    /**
+     * ClassWorld Launcher "embedded" entry point: returning exitCode and accepts Class World and streams.
+     */
+    public static int main(
+            String[] args,
+            ClassWorld world,
+            @Nullable InputStream stdIn,
+            @Nullable OutputStream stdOut,
+            @Nullable OutputStream stdErr)
+            throws IOException {
+        return new MavenCling(world).run(args, stdIn, stdOut, stdErr, true);
     }
 
     public MavenCling() {
@@ -64,9 +79,12 @@ protected Invoker createInvoker() {
     }
 
     @Override
-    protected InvokerRequest parseArguments(String[] args) {
-        return new MavenParser()
-                .parseInvocation(ParserRequest.mvn(args, new JLineMessageBuilderFactory())
-                        .build());
+    protected Parser createParser() {
+        return new MavenParser();
+    }
+
+    @Override
+    protected ParserRequest.Builder createParserRequestBuilder(String[] args) {
+        return ParserRequest.mvn(args, createMessageBuilderFactory());
     }
 }