Add more helpful error message when BBS download archive is not found (…

…#906)

RELEASENOTES.md

@@ -1,5 +1,6 @@
 - Improve error message when `migrate-repo` is used with a target personal access token (PAT) with insufficient permissions
 - Ensure `--no-ssl-verify` flag is honored when downloading archives from GHES
 - `--bbs-project` and `--bbs-repo` are now both required in `gh bbs2gh migrate-repo` command when `--bbs-server-url` is set
-* Added `--keep-archive` flag to `gh gei migrate-repo` and `gh gei generate-script`. When migrating from GHES this will skip the step where we delete the archive from your machine, leaving it around as a local file.
+- Added `--keep-archive` flag to `gh gei migrate-repo` and `gh gei generate-script`. When migrating from GHES this will skip the step where we delete the archive from your machine, leaving it around as a local file.
 - Continue to next mannequin mapping in `gh gei reclaim-mannequin --csv` if a username doesn't exist
+- Display more helpful message when the Bitbucket export archive is not found when using `gh bbs2gh migrate-repo`

src/bbs2gh/Services/BbsSmbArchiveDownloader.cs

@@ -205,7 +205,12 @@ private object CreateFileHandle(ISMBFileStore fileStore, string sharedFilePath)
 
         return IsSuccessStatus(status)
             ? sharedFileHandle
-            : throw new OctoshiftCliException($"Couldn't create SMB file handle for \"{sharedFilePath}\" (Status Code: {status}).");
+            : throw new OctoshiftCliException(
+                $"Couldn't create SMB file handle for \"{sharedFilePath}\" (Status Code: {status})." +
+                (IsObjectPathNotFoundStatus(status) && BbsSharedHomeDirectory is BbsSettings.DEFAULT_BBS_SHARED_HOME_DIRECTORY_WINDOWS
+                    ? "This most likely means that your Bitbucket instance uses a non-default Bitbucket shared home directory, so we couldn't find your archive. " +
+                      "You can point the CLI to a non-default shared directory by specifying the --bbs-shared-home option."
+                    : ""));
     }
 
     private long? GetFileSize(ISMBFileStore fileStore, object sharedFileHandle)
@@ -218,4 +223,6 @@ private object CreateFileHandle(ISMBFileStore fileStore, string sharedFilePath)
     private bool IsSuccessStatus(NTStatus status) => status is NTStatus.STATUS_SUCCESS;
 
     private bool IsEndOfFileStatus(NTStatus status) => status is NTStatus.STATUS_END_OF_FILE;
+
+    private bool IsObjectPathNotFoundStatus(NTStatus status) => status is NTStatus.STATUS_OBJECT_PATH_NOT_FOUND;
 }

src/bbs2gh/Services/BbsSshArchiveDownloader.cs

@@ -91,7 +91,12 @@ public async Task<string> Download(long exportJobId, string targetDirectory = IB
 
         if (!_sftpClient.Exists(sourceExportArchiveFullPath))
         {
-            throw new OctoshiftCliException($"Source export archive ({sourceExportArchiveFullPath}) does not exist.");
+            throw new OctoshiftCliException(
+                $"Source export archive ({sourceExportArchiveFullPath}) does not exist." +
+                (BbsSharedHomeDirectory is BbsSettings.DEFAULT_BBS_SHARED_HOME_DIRECTORY_LINUX
+                    ? "This most likely means that your Bitbucket instance uses a non-default Bitbucket shared home directory, so we couldn't find your archive. " +
+                      "You can point the CLI to a non-default shared directory by specifying the --bbs-shared-home option."
+                    : ""));
         }
 
         _fileSystemProvider.CreateDirectory(targetDirectory);