From b53cb57680a6fd7b383636ac2d6cd71003532915 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Fri, 4 Dec 2020 16:24:56 -0500 Subject: Initial implementation of volume plugins This implements support for mounting and unmounting volumes backed by volume plugins. Support for actually retrieving plugins requires a pull request to land in containers.conf and then that to be vendored, and as such is not yet ready. Given this, this code is only compile tested. However, the code for everything past retrieving the plugin has been written - there is support for creating, removing, mounting, and unmounting volumes, which should allow full functionality once the c/common PR is merged. A major change is the signature of the MountPoint function for volumes, which now, by necessity, returns an error. Named volumes managed by a plugin do not have a mountpoint we control; instead, it is managed entirely by the plugin. As such, we need to cache the path in the DB, and calls to retrieve it now need to access the DB (and may fail as such). Notably absent is support for SELinux relabelling and chowning these volumes. Given that we don't manage the mountpoint for these volumes, I am extremely reluctant to try and modify it - we could easily break the plugin trying to chown or relabel it. Also, we had no less than *5* separate implementations of inspecting a volume floating around in pkg/infra/abi and pkg/api/handlers/libpod. And none of them used volume.Inspect(), the only correct way of inspecting volumes. Remove them all and consolidate to using the correct way. Compat API is likely still doing things the wrong way, but that is an issue for another day. Fixes #4304 Signed-off-by: Matthew Heon --- libpod/define/volume_inspect.go | 51 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 libpod/define/volume_inspect.go (limited to 'libpod/define/volume_inspect.go') diff --git a/libpod/define/volume_inspect.go b/libpod/define/volume_inspect.go new file mode 100644 index 000000000..20602ea16 --- /dev/null +++ b/libpod/define/volume_inspect.go @@ -0,0 +1,51 @@ +package define + +import ( + "time" +) + +// InspectVolumeData is the output of Inspect() on a volume. It is matched to +// the format of 'docker volume inspect'. +type InspectVolumeData struct { + // Name is the name of the volume. + Name string `json:"Name"` + // Driver is the driver used to create the volume. + // If set to "local" or "", the Local driver (Podman built-in code) is + // used to service the volume; otherwise, a volume plugin with the given + // name is used to mount and manage the volume. + Driver string `json:"Driver"` + // Mountpoint is the path on the host where the volume is mounted. + Mountpoint string `json:"Mountpoint"` + // CreatedAt is the date and time the volume was created at. This is not + // stored for older Libpod volumes; if so, it will be omitted. + CreatedAt time.Time `json:"CreatedAt,omitempty"` + // Status is used to return information on the volume's current state, + // if the volume was created using a volume plugin (uses a Driver that + // is not the local driver). + // Status is provided to us by an external program, so no guarantees are + // made about its format or contents. Further, it is an optional field, + // so it may not be set even in cases where a volume plugin is in use. + Status map[string]interface{} `json:"Status,omitempty"` + // Labels includes the volume's configured labels, key:value pairs that + // can be passed during volume creation to provide information for third + // party tools. + Labels map[string]string `json:"Labels"` + // Scope is unused and provided solely for Docker compatibility. It is + // unconditionally set to "local". + Scope string `json:"Scope"` + // Options is a set of options that were used when creating the volume. + // For the Local driver, these are mount options that will be used to + // determine how a local filesystem is mounted; they are handled as + // parameters to Mount in a manner described in the volume create + // manpage. + // For non-local drivers, these are passed as-is to the volume plugin. + Options map[string]string `json:"Options"` + // UID is the UID that the volume was created with. + UID int `json:"UID,omitempty"` + // GID is the GID that the volume was created with. + GID int `json:"GID,omitempty"` + // Anonymous indicates that the volume was created as an anonymous + // volume for a specific container, and will be be removed when any + // container using it is removed. + Anonymous bool `json:"Anonymous,omitempty"` +} -- cgit v1.2.3-54-g00ecf