implemented a new auto configuration mechanism for mercurial on unix

This new mechanism is more robust and should find python and python3 installations

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/autoconfig/AutoConfigurator.java

@@ -0,0 +1,47 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020-present Cloudogu GmbH and Contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package sonia.scm.autoconfig;
+
+import sonia.scm.repository.HgConfig;
+import sonia.scm.util.SystemUtil;
+
+import java.nio.file.Path;
+import java.util.Optional;
+
+public interface AutoConfigurator {
+
+  static Optional<AutoConfigurator> get() {
+    // at the moment we have only support for unix based systems.
+    if (SystemUtil.isUnix()) {
+      return Optional.of(new UnixAutoConfigurator(System.getenv()));
+    }
+    return Optional.empty();
+  }
+
+  HgConfig configure();
+
+  HgConfig configure(Path hg);
+
+}

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/autoconfig/UnixAutoConfigurator.java

@@ -0,0 +1,210 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020-present Cloudogu GmbH and Contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package sonia.scm.autoconfig;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Splitter;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+import com.google.common.io.MoreFiles;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import sonia.scm.repository.HgConfig;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+
+public class UnixAutoConfigurator implements AutoConfigurator {
+
+  private static final Logger LOG = LoggerFactory.getLogger(UnixAutoConfigurator.class);
+
+  private static final List<String> ADDITIONAL_PATH = ImmutableList.of(
+    "/usr/bin",
+    "/usr/local/bin",
+    "/opt/local/bin"
+  );
+
+  private final Set<String> fsPaths;
+
+  private Executor executor = (Path binary, String... args) -> {
+    ProcessBuilder builder = new ProcessBuilder(
+      Lists.asList(binary.toString(), args).toArray(new String[0])
+    );
+    Process process = builder.start();
+    int rc = process.waitFor();
+    if (rc != 0) {
+      throw new IOException(binary.toString() + " failed with return code " + rc);
+    }
+    return process.getInputStream();
+  };
+
+  UnixAutoConfigurator(Map<String, String> env) {
+    this(env, ADDITIONAL_PATH);
+  }
+
+  UnixAutoConfigurator(Map<String, String> env, List<String> additionalPaths) {
+    String path = env.getOrDefault("PATH", "");
+    fsPaths = new LinkedHashSet<>();
+    fsPaths.addAll(Splitter.on(File.pathSeparator).splitToList(path));
+    fsPaths.addAll(additionalPaths);
+  }
+
+  @VisibleForTesting
+  void setExecutor(Executor executor) {
+    this.executor = executor;
+  }
+
+  @Override
+  public HgConfig configure() {
+    Optional<Path> hg = findInPath("hg");
+    if (hg.isPresent()) {
+      return configure(hg.get());
+    }
+    return new HgConfig();
+  }
+
+  private Optional<Path> findInPath(String binary) {
+    for (String directory : fsPaths) {
+      Path binaryPath = Paths.get(directory, binary);
+      if (Files.exists(binaryPath)) {
+        return Optional.of(binaryPath);
+      }
+    }
+    return Optional.empty();
+  }
+
+
+  private Optional<Path> findModulePath(Path hg) {
+    if (!Files.isExecutable(hg)) {
+      LOG.warn("{} is not executable", hg);
+      return Optional.empty();
+    }
+    try {
+      InputStream debuginstall = executor.execute(hg, "debuginstall");
+      try (BufferedReader reader = new BufferedReader(new InputStreamReader(debuginstall))) {
+        while (reader.ready()) {
+          String line = reader.readLine();
+          if (line.contains("installed modules")) {
+            int start = line.indexOf("(");
+            int end = line.indexOf(")");
+            Path modulePath = Paths.get(line.substring(start + 1, end));
+            if (Files.exists(modulePath)) {
+              return Optional.of(modulePath);
+            } else {
+              LOG.warn("could not find module path at {}", modulePath);
+            }
+          }
+        }
+      }
+    } catch (IOException ex) {
+      LOG.warn("failed to parse debuginstall of {}", hg);
+    } catch (InterruptedException e) {
+      LOG.warn("interrupted during debuginstall parsing of {}", hg);
+      Thread.currentThread().interrupt();
+    }
+    return Optional.empty();
+  }
+
+  @Override
+  public HgConfig configure(Path hg) {
+    HgConfig config = new HgConfig();
+    try {
+      if (Files.exists(hg)) {
+        configureWithExistingHg(hg, config);
+      } else {
+        LOG.warn("{} does not exists", hg);
+      }
+    } catch (IOException e) {
+      LOG.warn("failed to read first line of {}", hg);
+    }
+    return config;
+  }
+
+  private void configureWithExistingHg(Path hg, HgConfig config) throws IOException {
+    config.setHgBinary(hg.toAbsolutePath().toString());
+    Optional<Path> pythonFromShebang = findPythonFromShebang(hg);
+    if (pythonFromShebang.isPresent()) {
+      config.setPythonBinary(pythonFromShebang.get().toAbsolutePath().toString());
+    } else {
+      LOG.warn("could not find python from shebang, searching for python in path");
+      Optional<Path> python = findInPath("python");
+      if (!python.isPresent()) {
+        LOG.warn("could not find python in path, searching for python3 instead");
+        python = findInPath("python3");
+      }
+      if (python.isPresent()) {
+        config.setPythonBinary(python.get().toAbsolutePath().toString());
+      } else {
+        LOG.warn("could not find python in path");
+      }
+    }
+
+    Optional<Path> modulePath = findModulePath(hg);
+    if (modulePath.isPresent()) {
+      config.setPythonPath(modulePath.get().toAbsolutePath().toString());
+    } else {
+      LOG.warn("could not find module path");
+    }
+
+  }
+
+  private Optional<Path> findPythonFromShebang(Path hg) throws IOException {
+    String shebang = MoreFiles.asCharSource(hg, StandardCharsets.UTF_8).readFirstLine();
+    if (shebang != null && shebang.startsWith("#!")) {
+      String substring = shebang.substring(2);
+      String[] parts = substring.split("\\s+");
+      if (parts.length > 1) {
+        return findInPath(parts[1]);
+      } else {
+        Path python = Paths.get(parts[0]);
+        if (Files.exists(python)) {
+          return Optional.of(python);
+        } else {
+          LOG.warn("python binary from shebang {} does not exists", python);
+        }
+      }
+    } else {
+      LOG.warn("first line does not look like a shebang: {}", shebang);
+    }
+    return Optional.empty();
+  }
+
+  @FunctionalInterface
+  interface Executor {
+    InputStream execute(Path binary, String... args) throws IOException, InterruptedException;
+  }
+}

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/installer/MacOSHgInstaller.java

@@ -21,7 +21,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-    
+
 package sonia.scm.installer;
 
 //~--- non-JDK imports --------------------------------------------------------
@@ -40,7 +40,9 @@ import java.io.IOException;
 /**
  *
  * @author Sebastian Sdorra
+ * @deprecated use {@link sonia.scm.autoconfig.AutoConfigurator}
  */
+@Deprecated
 public class MacOSHgInstaller extends UnixHgInstaller
 {
 

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/installer/UnixHgInstaller.java

@@ -21,7 +21,7 @@
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */
-    
+
 package sonia.scm.installer;
 
 //~--- non-JDK imports --------------------------------------------------------
@@ -40,7 +40,9 @@ import java.util.List;
 /**
  *
  * @author Sebastian Sdorra
+ * @deprecated use {@link sonia.scm.autoconfig.AutoConfigurator}
  */
+@Deprecated
 public class UnixHgInstaller extends AbstractHgInstaller
 {
 

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/HgRepositoryHandler.java

@@ -33,6 +33,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.ConfigurationException;
 import sonia.scm.SCMContextProvider;
+import sonia.scm.autoconfig.AutoConfigurator;
 import sonia.scm.installer.HgInstaller;
 import sonia.scm.installer.HgInstallerFactory;
 import sonia.scm.io.ExtendedCommand;
@@ -55,6 +56,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.text.MessageFormat;
+import java.util.Optional;
 
 @Singleton
 @Extension
@@ -91,14 +93,11 @@ public class HgRepositoryHandler
     this.hgContextProvider = hgContextProvider;
     this.workingCopyFactory = workingCopyFactory;
 
-    try
-    {
+    try {
       this.jaxbContext = JAXBContext.newInstance(BrowserResult.class,
         BlameResult.class, Changeset.class, ChangesetPagingResult.class,
         HgVersion.class);
-    }
-    catch (JAXBException ex)
-    {
+    } catch (JAXBException ex) {
       throw new ConfigurationException("could not create jaxbcontext", ex);
     }
   }
@@ -139,7 +138,12 @@ public class HgRepositoryHandler
     super.loadConfig();
 
     if (config == null) {
-      doAutoConfiguration(new HgConfig());
+      HgConfig config = null;
+      Optional<AutoConfigurator> autoConfigurator = AutoConfigurator.get();
+      if (autoConfigurator.isPresent()) {
+        config = autoConfigurator.get().configure();
+      }
+      doAutoConfiguration(config != null ? config : new HgConfig());
     }
   }
 

scm-plugins/scm-hg-plugin/src/test/java/sonia/scm/autoconfig/UnixAutoConfiguratorTest.java

@@ -0,0 +1,164 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020-present Cloudogu GmbH and Contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package sonia.scm.autoconfig;
+
+import com.google.common.base.Joiner;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import org.assertj.core.util.Strings;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+import sonia.scm.repository.HgConfig;
+
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Collections;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class UnixAutoConfiguratorTest {
+
+  @Test
+  void shouldConfigureWithShebangPath(@TempDir Path directory) throws IOException {
+    Path hg = directory.resolve("hg");
+    Path python = directory.resolve("python");
+
+    Files.write(hg, ("#!" + python.toAbsolutePath().toString()).getBytes(StandardCharsets.UTF_8));
+    Files.createFile(python);
+
+    UnixAutoConfigurator configurator = create(directory);
+    HgConfig config = configurator.configure();
+
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonBinary()).isEqualTo(python.toString());
+  }
+
+  private UnixAutoConfigurator create(@TempDir Path directory) {
+    return new UnixAutoConfigurator(createEnv(directory), Collections.emptyList());
+  }
+
+  private Map<String, String> createEnv(Path... paths) {
+    return ImmutableMap.of("PATH", Joiner.on(File.pathSeparator).join(paths));
+  }
+
+  @Test
+  void shouldConfigureWithShebangEnv(@TempDir Path directory) throws IOException {
+    Path hg = directory.resolve("hg");
+    Path python = directory.resolve("python3.8");
+
+    Files.write(hg, "#!/usr/bin/env python3.8".getBytes(StandardCharsets.UTF_8));
+    Files.createFile(python);
+
+    UnixAutoConfigurator configurator = create(directory);
+    HgConfig config = configurator.configure();
+
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonBinary()).isEqualTo(python.toString());
+  }
+
+  @Test
+  void shouldConfigureWithoutShebang(@TempDir Path directory) throws IOException {
+    Path hg = directory.resolve("hg");
+    Path python = directory.resolve("python");
+
+    Files.createFile(hg);
+    Files.createFile(python);
+
+    UnixAutoConfigurator configurator = create(directory);
+    HgConfig config = configurator.configure();
+
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonBinary()).isEqualTo(python.toString());
+  }
+
+  @Test
+  void shouldConfigureWithoutShebangButWithPython3(@TempDir Path directory) throws IOException {
+    Path hg = directory.resolve("hg");
+    Path python = directory.resolve("python3");
+
+    Files.createFile(hg);
+    Files.createFile(python);
+
+    UnixAutoConfigurator configurator = create(directory);
+    HgConfig config = configurator.configure();
+
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonBinary()).isEqualTo(python.toString());
+  }
+
+  @Test
+  void shouldConfigureFindPythonInAdditionalPath(@TempDir Path directory) throws IOException {
+    Path def = directory.resolve("default");
+    Files.createDirectory(def);
+    Path additional = directory.resolve("additional");
+    Files.createDirectory(additional);
+
+    Path hg = def.resolve("hg");
+    Path python = additional.resolve("python");
+
+    Files.createFile(hg);
+    Files.createFile(python);
+
+    UnixAutoConfigurator configurator = new UnixAutoConfigurator(
+      createEnv(def), ImmutableList.of(additional.toAbsolutePath().toString())
+    );
+
+    HgConfig config = configurator.configure();
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonBinary()).isEqualTo(python.toString());
+  }
+
+  @Test
+  void shouldFindModulePathFromDebuginstallOutput(@TempDir Path directory) throws IOException {
+    Path hg = directory.resolve("hg");
+    Files.createFile(hg);
+    hg.toFile().setExecutable(true);
+
+    Path modules = directory.resolve("modules");
+    Files.createDirectories(modules);
+
+    UnixAutoConfigurator configurator = create(directory);
+    configurator.setExecutor((Path binary, String... args) -> {
+      String content = String.join("\n",
+        "checking Python executable (/python3.8)",
+        "checking Python lib (/python3.8)...",
+        "checking installed modules (" + modules.toString() + ")...",
+        "checking templates (/mercurial/templates)...",
+        "checking default template (/mercurial/templates/map-cmdline.default))"
+      );
+      return new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8));
+    });
+    HgConfig config = configurator.configure();
+
+    assertThat(config.getHgBinary()).isEqualTo(hg.toString());
+    assertThat(config.getPythonPath()).isEqualTo(modules.toString());
+  }
+
+}