From 1e6609dd463fa99f791346a81e63fe6788b6b61c Mon Sep 17 00:00:00 2001
From: Vladislav Rassokhin <vladislav.rassokhin@jetbrains.com>
Date: Wed, 15 Aug 2018 20:26:38 +0300
Subject: [PATCH] TW-56415 Try to update local git mirror several times instead
 of cloning from scratch

---
 .../vcs/git/agent/UpdaterWithMirror.java      | 39 +++++++++++++++++--
 1 file changed, 36 insertions(+), 3 deletions(-)

diff --git a/git-agent/src/jetbrains/buildServer/buildTriggers/vcs/git/agent/UpdaterWithMirror.java b/git-agent/src/jetbrains/buildServer/buildTriggers/vcs/git/agent/UpdaterWithMirror.java
index 755dd9d1..b50207a3 100644
--- a/git-agent/src/jetbrains/buildServer/buildTriggers/vcs/git/agent/UpdaterWithMirror.java
+++ b/git-agent/src/jetbrains/buildServer/buildTriggers/vcs/git/agent/UpdaterWithMirror.java
@@ -22,10 +22,12 @@ import jetbrains.buildServer.agent.SmartDirectoryCleaner;
 import jetbrains.buildServer.buildTriggers.vcs.git.GitUtils;
 import jetbrains.buildServer.buildTriggers.vcs.git.MirrorManager;
 import jetbrains.buildServer.buildTriggers.vcs.git.agent.errors.GitExecTimeout;
+import jetbrains.buildServer.util.StringUtil;
+import jetbrains.buildServer.util.ThreadUtil;
 import jetbrains.buildServer.vcs.CheckoutRules;
 import jetbrains.buildServer.vcs.VcsException;
 import jetbrains.buildServer.vcs.VcsRoot;
-import org.apache.log4j.Logger;
+import com.intellij.openapi.diagnostic.Logger;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.RepositoryBuilder;
@@ -35,6 +37,7 @@ import org.jetbrains.annotations.NotNull;
 import java.io.File;
 import java.io.IOException;
 import java.net.URISyntaxException;
+import java.util.List;
 import java.util.Map;
 
 /**
@@ -42,7 +45,7 @@ import java.util.Map;
  */
 public class UpdaterWithMirror extends UpdaterImpl {
 
-  private final static Logger LOG = Logger.getLogger(UpdaterWithMirror.class);
+  private final static Logger LOG = Logger.getInstance(UpdaterWithMirror.class.getName());
 
   public UpdaterWithMirror(@NotNull FS fs,
                            @NotNull AgentPluginConfig pluginConfig,
@@ -153,10 +156,23 @@ public class UpdaterWithMirror extends UpdaterImpl {
                            @NotNull String refspec) throws VcsException {
     removeRefLocks(repositoryDir);
     try {
-      fetch(repositoryDir, refspec, false);
+      final int[] retryTimeouts = getRetryTimeouts();
+      for (int i = 0; i <= retryTimeouts.length; i++) {
+        try {
+          fetch(repositoryDir, refspec, false);
+          break;
+        } catch (VcsException e) {
+          // Throw exception after latest attempt
+          if (i == retryTimeouts.length) throw e;
+          int wait = retryTimeouts[i];
+          LOG.warnAndDebugDetails("Failed to fetch mirror, will retry after " + wait + " seconds.", e);
+          ThreadUtil.sleep(wait * 1000);
+        }
+      }
     } catch (VcsException e) {
       if (myPluginConfig.isFailOnCleanCheckout() || !repeatFetchAttempt || !shouldFetchFromScratch(e))
         throw e;
+      LOG.warnAndDebugDetails("Failed to fetch mirror", e);
       if (cleanDir(repositoryDir)) {
         GitFacade git = myGitFactory.create(repositoryDir);
         git.init().setBare(true).call();
@@ -294,4 +310,21 @@ public class UpdaterWithMirror extends UpdaterImpl {
     }
     return branchName;
   }
+
+  private int[] getRetryTimeouts() {
+    String value = myBuild.getSharedConfigParameters().get("teamcity.git.fetchMirrorRetryTimeouts");
+    if (value == null) return new int[]{5, 10, 15, 30}; // total 60 seconds
+
+    List<String> split = StringUtil.split(value, true, ',');
+    int[] result = new int[split.size()];
+    for (int i = 0; i < result.length; i++) {
+      int parsed = 1;
+      try {
+        parsed = Integer.parseInt(split.get(i));
+      } catch (NumberFormatException ignored) {
+      }
+      result[i] = parsed;
+    }
+    return result;
+  }
 }
-- 
2.23.3