feat: add check for presence of commit before unshallowing

Author: daniel-mohedano

dd-java-agent/agent-ci-visibility/src/main/java/datadog/trace/civisibility/git/tree/GitClient.java

@@ -17,7 +17,10 @@ public interface GitClient {
 
   boolean isShallow() throws IOException, TimeoutException, InterruptedException;
 
-  void unshallow(@Nullable String remoteCommitReference, boolean shallowUntilCommit)
+  boolean isCommitPresent(String commitReference)
+      throws IOException, TimeoutException, InterruptedException;
+
+  void unshallow(@Nullable String remoteCommitReference, boolean unshallowUntilCommit)
       throws IOException, TimeoutException, InterruptedException;
 
   @Nullable

dd-java-agent/agent-ci-visibility/src/main/java/datadog/trace/civisibility/git/tree/GitRepoUnshallow.java

@@ -22,14 +22,17 @@ public GitRepoUnshallow(Config config, GitClient gitClient) {
 
   /**
    * Unshallows git repo up to a specific boundary commit, if provided, or up to the time limit
-   * configured in the git client if not.
+   * configured in the git client if not. Won't perform an unshallow action when a boundary is
+   * provided and the object is already present, or if the repository is already unshallowed.
    *
    * @param boundaryCommitSha used as boundary for the unshallowing if provided.
    * @return false if unshallowing is not enabled or unnecessary, true otherwise
    */
   public synchronized boolean unshallow(@Nullable String boundaryCommitSha)
       throws IOException, InterruptedException, TimeoutException {
-    if (!config.isCiVisibilityGitUnshallowEnabled() || !gitClient.isShallow()) {
+    if (!config.isCiVisibilityGitUnshallowEnabled()
+        || (boundaryCommitSha != null && gitClient.isCommitPresent(boundaryCommitSha))
+        || !gitClient.isShallow()) {
       return false;
     }
 

dd-java-agent/agent-ci-visibility/src/main/java/datadog/trace/civisibility/git/tree/NoOpGitClient.java

@@ -21,7 +21,12 @@ public boolean isShallow() {
   }
 
   @Override
-  public void unshallow(@Nullable String remoteCommitReference, boolean shallowUntilCommit) {
+  public boolean isCommitPresent(String commitReference) {
+    return false;
+  }
+
+  @Override
+  public void unshallow(@Nullable String remoteCommitReference, boolean unshallowUntilCommit) {
     // no op
   }
 

dd-java-agent/agent-ci-visibility/src/main/java/datadog/trace/civisibility/git/tree/ShellGitClient.java

@@ -99,6 +99,38 @@ public boolean isShallow() throws IOException, TimeoutException, InterruptedExce
         });
   }
 
+  /**
+   * Checks whether the provided reference object is present or not.
+   *
+   * @param commitReference to check presence of
+   * @return {@code true} if object is present, {@code false} otherwise
+   * @throws IOException If an error was encountered while writing command input or reading output
+   * @throws TimeoutException If timeout was reached while waiting for Git command to finish
+   * @throws InterruptedException If current thread was interrupted while waiting for Git command to
+   */
+  @Override
+  public boolean isCommitPresent(String commitReference)
+      throws IOException, TimeoutException, InterruptedException {
+    if (!GitUtils.isValidRef(commitReference)) {
+      return false;
+    }
+    return executeCommand(
+        Command.OTHER,
+        () -> {
+          try {
+            commandExecutor.executeCommand(
+                ShellCommandExecutor.OutputParser.IGNORE,
+                "git",
+                "cat-file",
+                "-e",
+                commitReference + "^{commit}");
+            return true;
+          } catch (ShellCommandExecutor.ShellCommandFailedException ignored) {
+            return false;
+          }
+        });
+  }
+
   /**
    * Returns the SHA of the head commit of the upstream (remote tracking) branch for the currently
    * checked-out local branch. If the local branch is not tracking any remote branches, a {@link
@@ -129,15 +161,15 @@ public String getUpstreamBranchSha() throws IOException, TimeoutException, Inter
    *
    * @param remoteCommitReference The commit to fetch from the remote repository, so local repo will
    *     be updated with this commit and its ancestors. If {@code null}, everything will be fetched.
-   * @param shallowUntilCommit Only unshallow up until the commit provided, or use the time limit
+   * @param unshallowUntilCommit Only unshallow up until the commit provided, or use the time limit
    *     configured if not. Ignored if no reference is provided.
    * @throws IOException If an error was encountered while writing command input or reading output
    * @throws TimeoutException If timeout was reached while waiting for Git command to finish
    * @throws InterruptedException If current thread was interrupted while waiting for Git command to
    *     finish
    */
   @Override
-  public void unshallow(@Nullable String remoteCommitReference, boolean shallowUntilCommit)
+  public void unshallow(@Nullable String remoteCommitReference, boolean unshallowUntilCommit)
       throws IOException, TimeoutException, InterruptedException {
     executeCommand(
         Command.UNSHALLOW,
@@ -150,7 +182,7 @@ public void unshallow(@Nullable String remoteCommitReference, boolean shallowUnt
               return (Void) null;
             }
             String boundaryArg =
-                shallowUntilCommit
+                unshallowUntilCommit
                     ? "--no-write-fetch-head"
                     : String.format("--shallow-since='%s'", latestCommitsSince);
             String commitSha = getSha(remoteCommitReference);

dd-java-agent/agent-ci-visibility/src/test/groovy/datadog/trace/civisibility/git/tree/GitClientTest.groovy

@@ -70,7 +70,7 @@ class GitClientTest extends Specification {
     upstreamBranch == "98b944cc44f18bfb78e3021de2999cdcda8efdf6"
   }
 
-  def "test unshallow: sha-#remoteSha fetchOnlyCommit-#fetchOnlyCommit"() {
+  def "test unshallow: sha-#remoteSha"() {
     given:
     givenGitRepo("ci/git/shallow/git")
 
@@ -84,7 +84,7 @@ class GitClientTest extends Specification {
     commits.size() == 1
 
     when:
-    gitClient.unshallow(remoteSha, fetchOnlyCommit)
+    gitClient.unshallow(remoteSha, false)
     shallow = gitClient.isShallow()
     commits = gitClient.getLatestCommits()
 
@@ -93,11 +93,33 @@ class GitClientTest extends Specification {
     commits.size() == numCommits
 
     where:
-    remoteSha                                  | fetchOnlyCommit | isShallow | numCommits
-    GitClient.HEAD                             | false           | false     | 10
-    null                                       | false           | false     | 10
-    "f4377e97f10c2d58696192b170b2fef2a8464b04" | true            | true      | 1
-    null                                       | true            | false     | 10
+    remoteSha      | isShallow | numCommits
+    GitClient.HEAD | false     | 10
+    null           | false     | 10
+  }
+
+  def "test unshallow using commit as boundary"() {
+    given:
+    givenGitRepo("ci/git/shallow/git")
+
+    when:
+    def commit = "f4377e97f10c2d58696192b170b2fef2a8464b04"
+    def gitClient = givenGitClient()
+    def shallow = gitClient.isShallow()
+    def isPresent = gitClient.isCommitPresent(commit)
+
+    then:
+    shallow
+    !isPresent
+
+    when:
+    gitClient.unshallow(commit, true)
+    shallow = gitClient.isShallow()
+    isPresent = gitClient.isCommitPresent(commit)
+
+    then:
+    shallow
+    isPresent
   }
 
   def "test get git folder"() {