From d4f6b9ddc783f853f88347dc9e7ebd52d6eea118 Mon Sep 17 00:00:00 2001
From: yo <johan@nosd.in>
Date: Sat, 18 Jun 2022 16:09:38 +0200
Subject: [PATCH] Add datastore list, filter and sort

---
 cmd/datastore.go | 108 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 cmd/datastore.go

diff --git a/cmd/datastore.go b/cmd/datastore.go
new file mode 100644
index 0000000..8e0f9f3
--- /dev/null
+++ b/cmd/datastore.go
@@ -0,0 +1,108 @@
+package cmd
+
+import (
+	"fmt"
+	"errors"
+	"reflect"
+	"strconv"
+	"strings"
+) 
+
+func ListDatastores(args []string, display bool) error {
+	/***************************************************************
+	/   Filter datastores by names given on command line
+	/**************************************************************/
+	for _, d := range args {
+		cmd := fmt.Sprintf("zfs list -p -H -o name,used,available,referenced %s", d)
+		out, err := executeCommand(cmd)
+		if err != nil {
+			if strings.HasSuffix(err.Error(), "No such file or directory") {
+				return errors.New(fmt.Sprintf("Datastore does not exist: %s", d))
+			} else {
+				return errors.New(fmt.Sprintf("Error executing command %s: %v; command returned: %s\n", cmd, err, out))
+			}
+		}
+		
+		fields := strings.Fields(out)
+		if len(fields) < 4 {
+			return errors.New(fmt.Sprintf("Error parsing output of \"%s\": Not enough fields", cmd))
+		}
+		u, _ := strconv.ParseUint(fields[1], 10, 64)
+		a, _ := strconv.ParseUint(fields[2], 10, 64)
+		r, _ := strconv.ParseUint(fields[3], 10, 64)
+		ds := Datastore{Name: d[1:], Mountpoint: d, ZFSDataset: fields[0], Used: u, Referenced: r, Available: a}
+		
+		err = loadDefaultsForDatastore(&ds)
+		if err != nil {
+			return err
+		}
+		
+		gDatastores = append(gDatastores, ds)
+	}
+	
+	fields := strings.Split(gDisplayDColumns, ",")
+
+	if true == display {
+		/***************************************************************
+		/   Sort datastores
+		/     We support 3 sort criteria max
+		/**************************************************************/
+		if len(gSortDSFields) > 0 && gSortDSFields != "none" {		
+			ds := initDatastoreSortStruct()
+
+			// The way we manage criteria quantity is not very elegant...
+			var fct1, fct2, fct3 *reflect.Value
+			for i, c := range strings.Split(gSortDSFields, ",") {
+				var fctName string
+				if strings.HasPrefix(c, "-") {
+					fctName = fmt.Sprintf("%sDec", strings.Replace(c, "-", "", 1))
+				} else { // Par defaut (pas de prefix +/-) on considere un tri incremental
+					fctName = fmt.Sprintf("%sInc", strings.Replace(c, "+", "", 1))
+				}
+
+				// Get function by its name
+				fct, _, err := getStructFieldValue(ds, fctName)
+				
+				if err != nil {
+					fieldName := strings.Replace(strings.Replace(c, "-", "", 1), "+", "", 1)
+					return errors.New(fmt.Sprintf("ERROR getting DatastoreSort struct field %s. Please check the field name: %s\n", fctName, fieldName))
+				}
+				switch i + 1 {
+				case 1:
+					fct1 = fct
+				case 2:
+					fct2 = fct
+				case 3:
+					fct3 = fct
+				}
+			}
+
+			switch len(strings.Split(gSortDSFields, ",")) {
+			case 1:
+				DatastoresOrderedBy(fct1.Interface().(datastoreLessFunc)).Sort(gDatastores)
+			case 2:
+				DatastoresOrderedBy(fct1.Interface().(datastoreLessFunc), fct2.Interface().(datastoreLessFunc)).Sort(gDatastores)
+			case 3:
+				DatastoresOrderedBy(fct1.Interface().(datastoreLessFunc), fct2.Interface().(datastoreLessFunc), fct3.Interface().(datastoreLessFunc)).Sort(gDatastores)
+			}
+		}
+		displayDatastoresFields(gDatastores, fields)
+	}
+	
+	return nil
+}
+
+/********************************************************************************
+ * Load jails default config from $datastore/defaults.json
+ *******************************************************************************/
+func loadDefaultsForDatastore(ds *Datastore) error {
+	jc, err := getJailConfig(fmt.Sprintf("%s/defaults.json", ds.Mountpoint))
+	if err != nil {
+		return err
+	}
+
+	ds.DefaultJailConfig = jc
+	//gDefaultConfig = append(gDefaultConfig, jc)
+
+	return nil
+}