Adds velero plugin for vsphere rock and sanity test

Adds the rock for the mentioned velero plugin.

Note that we're only building for amd64, since the plugin depends on
VDDX libraries from VMWare, and there doesn't seem to be support for arm64.

plugins/vsphere/rockcraft.yaml

@@ -0,0 +1,82 @@
+# Dockerfile: https://github.com/vmware-tanzu/velero/blob/v1.13.2/Dockerfile
+name: velero-plugin-for-vsphere
+summary: Velero Plugin for vSphere rock
+description: |
+    A rock containing the Velero Plugin for vSphere.
+
+    Velero gives you tools to back up and restore your Kubernetes cluster
+    resources and persistent volumes.
+license: Apache-2.0
+version: 1.5.2
+
+base: [email protected]
+build-base: [email protected]
+run-user: _daemon_
+
+platforms:
+  amd64:
+
+environment:
+  APP_VERSION: 1.5.2
+  LD_LIBRARY_PATH: /plugins
+
+# Services to be loaded by the Pebble entrypoint
+services:
+  install-plugin:
+    override: replace
+    startup: enabled
+    command: "bash /scripts/install.sh"
+    on-success: shutdown
+    on-failure: shutdown
+
+parts:
+  dependencies:
+    plugin: dump
+    source: https://gvddk-libs.s3-us-west-1.amazonaws.com/VMware-vix-disklib-7.0.2-17696664.x86_64.tar.gz
+    source-type: tar
+    override-build: |
+      craftctl default
+      # We need these libs for building and running the plugin.
+      mkdir /usr/local/vmware-vix-disklib-distrib
+      cp -r ./* /usr/local/vmware-vix-disklib-distrib/
+    organize:
+      # The LD_LIBRARY_PATH is set to /plugins.
+      lib64: ./plugins
+    prime:
+      - ./plugins
+
+  build-plugin:
+    after: [dependencies]
+    plugin: go
+    source: https://github.com/vmware-tanzu/velero-plugin-for-vsphere.git
+    source-type: git
+    source-tag: v${CRAFT_PROJECT_VERSION}
+    source-depth: 1
+    build-snaps:
+      - go/1.18/stable
+    build-environment:
+      - CGO_ENABLED: 1
+      - GO111MODULE: "on"
+      - GOOS: linux
+      - GOARCH: $CRAFT_ARCH_BUILD_FOR
+      - VERSION: ${CRAFT_PROJECT_VERSION}
+      - PKG: github.com/vmware-tanzu/velero-plugin-for-vsphere
+      - REGISTRY: canonical
+      - LDFLAGS: >
+          -X ${PKG}/pkg/buildinfo.Version=${VERSION} -X ${PKG}/pkg/buildinfo.Registry=${REGISTRY}
+    go-buildtags:
+      - mod=readonly
+      - installsuffix=static
+    go-generate:
+      - ./cmd/datamgr
+      - ./cmd/backup-driver
+      - ./cmd/plugin
+    override-build: |
+      craftctl default
+      mkdir -p "${CRAFT_PART_INSTALL}/scripts/"
+      cp scripts/install.sh "${CRAFT_PART_INSTALL}/scripts/"
+      chmod +x "${CRAFT_PART_INSTALL}/scripts/install.sh"
+    organize:
+      bin/data-*: ./
+      bin/backup-driver*: ./
+      bin/velero-*: ./plugins/

tests/sanity/test_velero_plugin_for_vsphere.py

@@ -0,0 +1,45 @@
+#
+# Copyright 2024 Canonical, Ltd.
+#
+
+import os
+
+from k8s_test_harness.util import docker_util
+
+ROCK_EXPECTED_FILES = [
+    "/backup-driver",
+    "/data-manager-for-plugin",
+    "/plugins/libvixDiskLib.so",
+    "/plugins/velero-plugin-for-vsphere",
+    "/scripts/install.sh",
+]
+
+
+def test_velero_plugin_for_vsphere_rock():
+    """Test Velero plugin for vSphere rock."""
+
+    image_variable = "ROCK_VELERO_PLUGIN_FOR_VSPHERE"
+    image = os.getenv(image_variable)
+    assert image is not None, f"${image_variable} is not set"
+
+    # check rock filesystem.
+    docker_util.ensure_image_contains_paths(image, ROCK_EXPECTED_FILES)
+
+    # check binaries.
+    process = docker_util.run_in_docker(image, ["/backup-driver", "--help"])
+    assert "Backup driver is a component in Velero vSphere plugin" in process.stdout
+
+    process = docker_util.run_in_docker(image, ["/data-manager-for-plugin", "--help"])
+    assert "Data manager is a component in Velero vSphere plugin" in process.stdout
+
+    process = docker_util.run_in_docker(
+        image, ["/plugins/velero-plugin-for-vsphere"], False
+    )
+    expected_err = (
+        "This binary is a plugin. These are not meant to be executed directly."
+    )
+    assert expected_err in process.stderr
+
+    # check script.
+    process = docker_util.run_in_docker(image, ["/scripts/install.sh"], False)
+    assert "No namespace specified in the namespace file" in process.stdout