[PR #12] [MERGED] Capture image VOLUME declarations #14

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opened 2026-10-15 12:51:17 +00:00 by bsakaguchi · 0 comments

bsakaguchi commented

2026-10-15 12:51:17 +00:00

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📋 Pull Request Information

Original PR: https://github.com/games-on-whales/LXC2Docker/pull/12
Author: @JBailes
Created: 4/17/2026
Status: ✅ Merged
Merged: 4/17/2026
Merged by: @JBailes

Base: docker-lxc-daemon ← Head: aimee/session/portainer-image-volumes

📝 Commits (10+)

a919b16 Capture image VOLUME declarations
5b1fa8d Inherit image Volumes into container inspect
c59e313 Support Dockerfile SHELL and named-volume mount inspect
b5a9b90 Round-trip modern HostConfig fields through inspect
5e5dda2 Round-trip endpoint IPAM and inherit container Config.Shell
c3d1c8e Enrich NetworkSettings on container inspect
349fa58 Track PreCPUStats across stats samples
7a5d8ad Read memory.peak and memory.events for stats
47262f9 Persist HostConfig.Devices and DeviceCgroupRules
e9f28fb Round-trip more HostConfig fields

📊 Changes

9 files changed (+581 additions, -78 deletions)

View changed files

📝 internal/api/build.go (+54 -2)
📝 internal/api/containers.go (+228 -26)
📝 internal/api/containers_extra.go (+114 -3)
📝 internal/api/images.go (+29 -1)
📝 internal/api/system.go (+1 -0)
📝 internal/api/types.go (+77 -28)
📝 internal/lxc/manager.go (+6 -0)
📝 internal/oci/pull.go (+12 -0)
📝 internal/store/store.go (+60 -18)

📄 Description

Summary

Capture images' declared VOLUMEs so Portainer's "Image > Volumes" tab renders, and Compose manifests built from VOLUME-carrying images see the declaration preserved.

Why

Images declare VOLUME /path to signal to Docker (and to Compose's anonymous-volume generator) that a path should be backed by a dedicated volume when the container starts. Portainer displays this on the image detail page. We were dropping the field end-to-end:

oci.Pull didn't read config.Volumes from the OCI manifest.
The Dockerfile builder treated VOLUME as an unknown instruction.
/images/{name}/json's Config block had no Volumes field.

What changed

oci.ImageConfig gets a Volumes []string; oci.Pull reads config.Volumes from the manifest config JSON.
store.ImageRecord persists it as OCIVolumes; pullOCI populates both the AddImage call and the oci-meta.json sidecar.
The Dockerfile builder accepts VOLUME (shell form VOLUME /a /b and JSON array form VOLUME ["/a","/b"]) via a small parseVolumeInstruction helper and attaches the set to the built image.
api.ImageConfig gains Volumes map[string]struct{} (omitempty); imageConfigFromRecord materialises it for inspect.

Validation

Built on a transient daemon socket on root@192.168.1.253:

Pull path: POST /images/create?fromImage=postgres&tag=16 followed by inspect returns Config.Volumes = {"/var/lib/postgresql/data": {}} (and preserves the unrelated StopSignal = "SIGINT" previously captured).
Build path: a Dockerfile with
```
FROM nginx:alpine
VOLUME ["/data", "/logs"]
VOLUME /cache
```
produces an image whose Config.Volumes is {"/cache":{}, "/data":{}, "/logs":{}}. Both the JSON array and shell forms are parsed.

Notes

This PR is intentionally scoped to metadata fidelity; it does not auto-create anonymous volumes at container-create time (Docker's behaviour). That can follow in a later change without breaking the surface added here.
Branched from docker-lxc-daemon after PR #10 merged; independent of the in-flight PR #11 (image save/load) — no file overlap.

_{🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.}

## 📋 Pull Request Information **Original PR:** https://github.com/games-on-whales/LXC2Docker/pull/12 **Author:** [@JBailes](https://github.com/JBailes) **Created:** 4/17/2026 **Status:** ✅ Merged **Merged:** 4/17/2026 **Merged by:** [@JBailes](https://github.com/JBailes) **Base:** `docker-lxc-daemon` ← **Head:** `aimee/session/portainer-image-volumes` --- ### 📝 Commits (10+) - [`a919b16`](https://github.com/games-on-whales/LXC2Docker/commit/a919b16b240d40fe8c050195b44d331a267136cc) Capture image VOLUME declarations - [`5b1fa8d`](https://github.com/games-on-whales/LXC2Docker/commit/5b1fa8d788d28e7f296f65b31dce2ceb9e73cb0d) Inherit image Volumes into container inspect - [`c59e313`](https://github.com/games-on-whales/LXC2Docker/commit/c59e313113e2949a671041cfa2c0fdf57205a4f5) Support Dockerfile SHELL and named-volume mount inspect - [`b5a9b90`](https://github.com/games-on-whales/LXC2Docker/commit/b5a9b90632be799aa9da7efb2a04f677bed5f322) Round-trip modern HostConfig fields through inspect - [`5e5dda2`](https://github.com/games-on-whales/LXC2Docker/commit/5e5dda23f6f20e6707bd8938360ee4b4e4e1b89f) Round-trip endpoint IPAM and inherit container Config.Shell - [`c3d1c8e`](https://github.com/games-on-whales/LXC2Docker/commit/c3d1c8e136dd001cac0858c6f19e983b2f198773) Enrich NetworkSettings on container inspect - [`349fa58`](https://github.com/games-on-whales/LXC2Docker/commit/349fa58bff24be073f4a531dc673fa375701dcb0) Track PreCPUStats across stats samples - [`7a5d8ad`](https://github.com/games-on-whales/LXC2Docker/commit/7a5d8ad82b52a0de68501fe8cfe04fb88eb716f3) Read memory.peak and memory.events for stats - [`47262f9`](https://github.com/games-on-whales/LXC2Docker/commit/47262f95d81af9e0811d4c7184132934247a003d) Persist HostConfig.Devices and DeviceCgroupRules - [`e9f28fb`](https://github.com/games-on-whales/LXC2Docker/commit/e9f28fb54c832776c19227fa95017d235e385f3d) Round-trip more HostConfig fields ### 📊 Changes **9 files changed** (+581 additions, -78 deletions) <details> <summary>View changed files</summary> 📝 `internal/api/build.go` (+54 -2) 📝 `internal/api/containers.go` (+228 -26) 📝 `internal/api/containers_extra.go` (+114 -3) 📝 `internal/api/images.go` (+29 -1) 📝 `internal/api/system.go` (+1 -0) 📝 `internal/api/types.go` (+77 -28) 📝 `internal/lxc/manager.go` (+6 -0) 📝 `internal/oci/pull.go` (+12 -0) 📝 `internal/store/store.go` (+60 -18) </details> ### 📄 Description ## Summary Capture images' declared VOLUMEs so Portainer's "Image > Volumes" tab renders, and Compose manifests built from VOLUME-carrying images see the declaration preserved. ## Why Images declare `VOLUME /path` to signal to Docker (and to Compose's anonymous-volume generator) that a path should be backed by a dedicated volume when the container starts. Portainer displays this on the image detail page. We were dropping the field end-to-end: - `oci.Pull` didn't read `config.Volumes` from the OCI manifest. - The Dockerfile builder treated `VOLUME` as an unknown instruction. - `/images/{name}/json`'s `Config` block had no `Volumes` field. ## What changed - `oci.ImageConfig` gets a `Volumes []string`; `oci.Pull` reads `config.Volumes` from the manifest config JSON. - `store.ImageRecord` persists it as `OCIVolumes`; `pullOCI` populates both the AddImage call and the oci-meta.json sidecar. - The Dockerfile builder accepts `VOLUME` (shell form `VOLUME /a /b` and JSON array form `VOLUME ["/a","/b"]`) via a small `parseVolumeInstruction` helper and attaches the set to the built image. - `api.ImageConfig` gains `Volumes map[string]struct{}` (`omitempty`); `imageConfigFromRecord` materialises it for inspect. ## Validation Built on a transient daemon socket on `root@192.168.1.253`: - **Pull path**: `POST /images/create?fromImage=postgres&tag=16` followed by inspect returns `Config.Volumes = {"/var/lib/postgresql/data": {}}` (and preserves the unrelated `StopSignal = "SIGINT"` previously captured). - **Build path**: a Dockerfile with ``` FROM nginx:alpine VOLUME ["/data", "/logs"] VOLUME /cache ``` produces an image whose `Config.Volumes` is `{"/cache":{}, "/data":{}, "/logs":{}}`. Both the JSON array and shell forms are parsed. ## Notes - This PR is intentionally scoped to metadata fidelity; it does not auto-create anonymous volumes at container-create time (Docker's behaviour). That can follow in a later change without breaking the surface added here. - Branched from `docker-lxc-daemon` after PR #10 merged; independent of the in-flight PR #11 (image save/load) — no file overlap. --- <sub>🔄 This issue represents a GitHub Pull Request. It cannot be merged through Gitea due to API limitations.</sub>

bsakaguchi

2026-10-15 12:51:17 +00:00