appendix: 23 Code-Ausschnitte aus dem Houston-Repository

Pin nixpkgs to the revision used by itc.componentware: the channel version
ships a latexminted that crashes on Python 3.14, which made every listing
fail and sent latexmk into an endless error prompt. Also force
nonstopmode/halt-on-error so a broken listing can never loop again.

figures/code/rename-customer-folder.cs

@@ -0,0 +1,54 @@
+/// <summary>
+/// todo: this function can currently cause dataloss. see #10070
+/// </summary>
+/// <returns>success</returns>
+private async Task<bool> RenameCustomerFolderAsync(
+    OrgSlug source, OrgSlug destination, OrgId owner, CancellationToken cancellationToken)
+{
+    if (source == destination)
+        return true;
+
+    if (!await CanClaimCustomerFolderAsync(destination, owner, cancellationToken))
+        return false;
+
+    var sourcePrefix = source.ToString();
+    var destinationPrefix = destination.ToString();
+
+    var sourceKeys = await ListKeysAsync(sourcePrefix, cancellationToken);
+
+    // The marker of the customer folder carries the efecte-org-id, so it is copied last and
+    // deleted first: the destination only becomes resolvable once it is complete. Everything
+    // below the customer folder keeps its relative key, including subfolders Houston does not
+    // know, so no document ever ends up somewhere else.
+    var documentKeys = sourceKeys.Where(key => key != sourcePrefix).ToList();
+    var markerKeys = sourceKeys.Where(key => key == sourcePrefix).ToList();
+    var copiedKeys = new List<string>(sourceKeys.Count);
+
+    try
+    {
+        foreach (var key in documentKeys.Concat(markerKeys))
+        {
+            var destinationKey = destinationPrefix + key[sourcePrefix.Length..];
+            await CopyObjectAsync(key, destinationKey, cancellationToken);
+            copiedKeys.Add(destinationKey);
+        }
+    }
+    catch (AmazonS3Exception exception)
+    {
+        ExceptionlessClient.Default.SubmitLog(
+        $"Could not move customer folder '{source}' to '{destination}': {exception.Message}. "
+        + "The folder stays where it is.", LogLevel.Error);
+
+        // Leftover copies would block every later attempt, because the destination is only
+        // claimed while it is empty. Cleaning them up keeps the move retryable.
+        await TryDeleteObjectsAsync(copiedKeys, cancellationToken);
+        return false;
+    }
+
+    // From here on the destination is authoritative. A failure while deleting only leaves
+    // garbage behind, the customer already sees all of his documents under the new name.
+    await TryDeleteObjectsAsync(documentKeys, cancellationToken);
+    await TryDeleteObjectsAsync(markerKeys, cancellationToken);
+
+    return true;
+}