[Request]: Storage - Add `container volume cp` command to copy data to and from volumes

[realrajaryan]

Feature or enhancement request details

Add ability to copy files and directories to and from volumes without requiring a running container. This simplifies volume data management for backups, seeding data, and extraction.

Basic requirements:

• Copy files/directories from host to volume
• Copy files/directories from volume to host
• Preserve file permissions and attributes
• Support recursive directory copying

Example usage:

# Copy to volume
container volume cp /path/on/host myvolume:/path/in/volume

# Copy from volume
container volume cp myvolume:/path/in/volume /path/on/host

# Copy directory recursively
container volume cp -r /local/data myvolume:/data

This avoids the current workaround of mounting the volume to a temporary container just to copy data in and out.

Code of Conduct

• I agree to follow this project's Code of Conduct

[PhantomInTheWire]

i could work on this

[realrajaryan]

i could work on this

@PhantomInTheWire Thanks for picking this up! I’d suggest using this thread to discuss your approach and get some feedback before you start implementing, since there might be some caveats. This will make both development and review much smoother :)

[PhantomInTheWire]

hey @realrajaryan i was thinking something where data flow looks like this

Host → Volume

1. CLI: Create tar of local files → pipe.write
2. CLI: Dup pipe.read FD → send to XPC
3. Daemon: Receive FD →uncompress() → extract to volume path

Volume → Host

1. CLI: Dup pipe.write FD → send to XPC with copyOut request
2. Daemon: compress() from volume path → write to FD
3. XPC: Stream tar data back to CLI (through the FD)
4. CLI: Read from pipe → uncompress() → extract to temp dir → move to destination

for the compress() uncompress() i think extending Archiver.swift with func uncompress(...) and func compress(...) to handle writes to file handle(pipe).

I was wondering if this is enough or should we also support volume to volume copies(i think it would be cool if that could happen but i think we should make that a follow up pr with a separate issue of its own)

[PhantomInTheWire]

hey @realrajaryan i have a pr open for this at #963 could you take a look and help review it? thanks.