Fix incorrect conversion between int types (#3205)

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

pkg/function/scale_workload.go

@@ -167,8 +167,8 @@ func (s *scaleWorkloadFunc) setArgs(tp param.TemplateParams, args map[string]int
 	case int64:
 		replicas = int32(val)
 	case string:
-		var v int
-		if v, err = strconv.Atoi(val); err != nil {
+		v, err := strconv.ParseInt(val, 10, 32)
+		if err != nil {
 			return errkit.Wrap(err, fmt.Sprintf("Cannot convert %s to int", val))
 		}
 		replicas = int32(v)

pkg/function/scale_workload_test.go

@@ -0,0 +1,46 @@
+package function
+
+import (
+	"gopkg.in/check.v1"
+
+	"github.com/kanisterio/kanister/pkg/param"
+)
+
+type ScaleWorkloadSuite struct{}
+
+var _ = check.Suite(&ScaleWorkloadSuite{})
+
+func (s *ScaleWorkloadSuite) TestSetArgs(c *check.C) {
+	stsParams := &param.StatefulSetParams{}
+	for _, tc := range []struct {
+		replicas         interface{}
+		expectedReplicas int32
+	}{
+		{
+			replicas:         4,
+			expectedReplicas: 4,
+		},
+		{
+			replicas:         234324,
+			expectedReplicas: 234324,
+		},
+		{
+			replicas:         234324,
+			expectedReplicas: 234324,
+		},
+		{
+			replicas:         2147483647,
+			expectedReplicas: 2147483647, // 2147483647 is the maximum value int32 can hold
+		},
+	} {
+		s := scaleWorkloadFunc{}
+		err := s.setArgs(param.TemplateParams{
+			StatefulSet: stsParams,
+		}, map[string]interface{}{
+			"replicas": tc.replicas,
+		})
+
+		c.Assert(err, check.IsNil)
+		c.Assert(s.replicas, check.Equals, tc.expectedReplicas)
+	}
+}