feat: include client6 build info in the resources

Replaced git-commit-id-maven-plugin with an better-maintained mirror.
The original packaged lacked native Git support, which would impede
the plugin if git-worktrees were used.

Author: bevzzz

pom.xml

@@ -360,6 +360,28 @@
             </execution>
           </executions>
         </plugin>
+        <plugin>
+          <groupId>pl.project13.maven</groupId>
+            <artifactId>git-commit-id-plugin</artifactId>
+            <version>4.9.10</version>
+            <executions>
+                <execution>
+                    <id>get-the-git-infos</id>
+                    <goals>
+                        <goal>revision</goal>
+                    </goals>
+                    <phase>initialize</phase>
+                </execution>
+            </executions>
+            <configuration>
+                <useNativeGit>true</useNativeGit>
+                <generateGitPropertiesFile>true</generateGitPropertiesFile>
+                <generateGitPropertiesFilename>${project.build.outputDirectory}/client6-git.properties</generateGitPropertiesFilename>
+                <commitIdGenerationMode>full</commitIdGenerationMode>
+                <failOnNoGitDirectory>false</failOnNoGitDirectory>
+                <failOnUnableToExtractRepoInfo>false</failOnUnableToExtractRepoInfo>
+            </configuration>
+        </plugin>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-javadoc-plugin</artifactId>
@@ -522,6 +544,10 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
       </plugin>
+      <plugin>
+            <groupId>pl.project13.maven</groupId>
+            <artifactId>git-commit-id-plugin</artifactId>
+      </plugin>
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-gpg-plugin</artifactId>

src/main/java/io/weaviate/client6/v1/internal/BuildInfo.java

@@ -0,0 +1,28 @@
+package io.weaviate.client6.v1.internal;
+
+import java.io.IOException;
+import java.util.Properties;
+
+public final class BuildInfo {
+  /** Prevent public initialization. */
+  private BuildInfo() {
+  }
+
+  public static final String BRANCH;
+  public static final String COMMIT_ID;
+  public static final String COMMIT_ID_ABBREV;
+
+  static {
+    var properties = new Properties();
+
+    try {
+      properties.load(BuildInfo.class.getClassLoader().getResourceAsStream("client6-git.properties"));
+    } catch (IOException | NullPointerException e) {
+      System.out.println("failed to load client6-git.properties, no build information will be available");
+    }
+
+    BRANCH = String.valueOf(properties.get("git.branch"));
+    COMMIT_ID = String.valueOf(properties.get("git.commit.id.full"));
+    COMMIT_ID_ABBREV = String.valueOf(properties.get("git.commit.id.abbrev"));
+  }
+}

src/test/java/io/weaviate/client6/v1/internal/BuildInfoTest.java

@@ -0,0 +1,35 @@
+package io.weaviate.client6.v1.internal;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+import org.assertj.core.api.Assertions;
+import org.junit.Test;
+
+public class BuildInfoTest {
+
+  @Test
+  public void testBuildInfo() throws IOException {
+    Assertions.assertThat(BuildInfo.BRANCH).as("branch").isEqualTo(gitBranch());
+    Assertions.assertThat(BuildInfo.COMMIT_ID).as("commit.full").isEqualTo(gitCommit());
+    Assertions.assertThat(gitCommit()).as("commit.abbrev").startsWith(BuildInfo.COMMIT_ID_ABBREV);
+  }
+
+  /** Get current non-abbreviated Git commit hash. */
+  private static String gitCommit() throws IOException {
+    return runCommand("git", "rev-parse", "HEAD");
+  }
+
+  /** Get current git branch. */
+  private static String gitBranch() throws IOException {
+    return runCommand("git", "branch", "--show-current");
+  }
+
+  /** Run shell command and return the output as multi-line string. */
+  private static String runCommand(String... cmdarray) throws IOException {
+    var process = Runtime.getRuntime().exec(cmdarray);
+    var r = new BufferedReader(new InputStreamReader(process.getInputStream()));
+    return String.join("\n", (Iterable<String>) () -> r.lines().iterator());
+  }
+}