Add kubectl dba adopt milvus: adopt a running Milvus in place

pkg/adopt/adopt.go

@@ -0,0 +1,43 @@
+/*
+Copyright AppsCode Inc. and Contributors
+Licensed under the AppsCode Community License 1.0.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    https://github.com/appscode/licenses/raw/1.0.0/AppsCode-Community-1.0.0.md
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package adopt implements `kubectl dba adopt`, which brings a database that
+// already runs in Kubernetes (for example from a Helm chart) under KubeDB in
+// place: the data stays where it is and the workloads change hands one role at
+// a time.
+package adopt
+
+import (
+	"github.com/spf13/cobra"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+	"k8s.io/kubectl/pkg/util/i18n"
+	"k8s.io/kubectl/pkg/util/templates"
+)
+
+// NewCmdAdopt returns the `adopt` command group.
+func NewCmdAdopt(f cmdutil.Factory) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "adopt",
+		Short: i18n.T("Bring a running database under KubeDB in place, without moving its data"),
+		Long: templates.LongDesc(`
+			Take over a database that already runs in Kubernetes, for example one
+			installed by a Helm chart. The data stays in its current storage, the
+			credentials stay the same, and clients keep their address; only the
+			workloads change hands, one role at a time.`),
+		Run:                   func(cmd *cobra.Command, args []string) {},
+		DisableFlagsInUseLine: true,
+		DisableAutoGenTag:     true,
+	}
+	cmd.AddCommand(NewCmdMilvus(f))
+	return cmd
+}

pkg/adopt/findings.go

@@ -0,0 +1,61 @@
+/*
+Copyright AppsCode Inc. and Contributors
+Licensed under the AppsCode Community License 1.0.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    https://github.com/appscode/licenses/raw/1.0.0/AppsCode-Community-1.0.0.md
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package adopt
+
+import (
+	"fmt"
+	"io"
+)
+
+const (
+	levelError = "ERROR"
+	levelWarn  = "WARN"
+	levelInfo  = "OK"
+)
+
+type finding struct {
+	Level string
+	Msg   string
+}
+
+// findings are the results of the pre-flight checks. An ERROR blocks the
+// adoption; a WARN needs a look before the handover.
+type findings []finding
+
+func (f *findings) errorf(format string, a ...any) {
+	*f = append(*f, finding{levelError, fmt.Sprintf(format, a...)})
+}
+
+func (f *findings) warnf(format string, a ...any) {
+	*f = append(*f, finding{levelWarn, fmt.Sprintf(format, a...)})
+}
+
+func (f *findings) infof(format string, a ...any) {
+	*f = append(*f, finding{levelInfo, fmt.Sprintf(format, a...)})
+}
+
+func (f findings) hasErrors() bool {
+	for _, x := range f {
+		if x.Level == levelError {
+			return true
+		}
+	}
+	return false
+}
+
+func (f findings) print(w io.Writer) {
+	for _, x := range f {
+		_, _ = fmt.Fprintf(w, "  [%-5s] %s\n", x.Level, x.Msg)
+	}
+}