Appendix 8.A Message Reference

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Direction	Line	Defined in
Requester → editor	The request (first line, no `type`)	§8.4
Editor → requester	`{"type":"apply","sd":…,"parts":[…],"propagate":…}`	§8.5
Requester → editor	`{"type":"progress","done":…,"at":…}` (while pushing into what is inside; no answer)	§8.5
Editor → requester	`{"type":"stop"}` (while pushing into what is inside; no answer)	§8.5
Requester → editor	`{"type":"applied","done":…,"failed":[…],"stopped":…}` (the last three only after pushing)	§8.5
Requester → editor	`{"type":"failed","why":…}`	§8.5
Requester → editor	`{"type":"raise"}` (the object asked for again; no answer)	§8.3

8.A.1 An example #

A file explorer opens the permissions of a file. The person adds Everyone with Read and presses Apply, which fails, then changes their mind and closes the dialog. Lines are shown on several lines here for reading. On the channel each is one line, and the descriptors are shortened.

→ {"object":{"name":"notes.txt","kind":"File","container":false,
             "parent":{"name":"/home/dana","sd":"AQAEgBQAAAAkAAAA…"}},
   "sd":"AQAEgBQAAAAkAAAAAAAAADQAAAAB…",
   "read":["owner","group","dacl","label"],
   "rights":[{"name":"Full control","mask":2032127,"general":true},
             {"name":"Read","mask":1179785,"general":true}],
   "generic":{"read":1179785,"write":1179926,"execute":1179808,"all":2032127},
   "can":{"owner":true,"audit":false,"label":true}}
← {"type":"apply","sd":"AQAEgBQAAAAkAAAAAAAAADQAAAAC…","parts":["dacl"]}
→ {"type":"failed","why":"you are not allowed to"}

The editor shows why and stays open. The person closes it, and the requester reads end-of-file on the editor's output.

The requester could read the label but not the rest of the SACL, so read names label and not sacl, and the SACL in sd holds the label alone. Had the person raised the label, the editor would have sent "parts":["label"].

8.A.2 Pushing into what is inside #

The same explorer opens a folder's permissions, saying it can push into what is inside. The person gives Finance Modify on the folder and everything in it, presses OK, says yes to updating what is already inside, and stops partway.

→ {"object":{"name":"finance","kind":"Folder","container":true}, …,
   "can":{"owner":true,"audit":true,"label":true,"propagate":true}}
← {"type":"apply","sd":"AQAEnBQAAAAkAAAA…","parts":["dacl"],"propagate":true}
→ {"type":"progress","done":120,"at":"/srv/finance/2025/q3.xlsx"}
→ {"type":"progress","done":480,"at":"/srv/finance/2026/budget"}
← {"type":"stop"}
→ {"type":"applied","done":512,
   "failed":[{"name":"/srv/finance/archive","why":"you are not allowed to"}],
   "stopped":true}

The folder's DACL was applied, and 512 items inside were updated before the walk stopped. The editor shows that, and what could not be done, and stays open though OK was pressed. The person can push the rest with another apply of the same parts.

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