fix: handle expiration date in regard to changed timezones (#667)

stackit/internal/utils/attributes.go

@@ -0,0 +1,46 @@
+package utils
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/hashicorp/terraform-plugin-framework/diag"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+	"github.com/stackitcloud/terraform-provider-stackit/stackit/internal/core"
+)
+
+type attributeGetter interface {
+	GetAttribute(ctx context.Context, attributePath path.Path, target interface{}) diag.Diagnostics
+}
+
+func ToTime(ctx context.Context, format string, val types.String, target *time.Time) (diags diag.Diagnostics) {
+	var err error
+	text := val.ValueString()
+	*target, err = time.Parse(format, text)
+	if err != nil {
+		core.LogAndAddError(ctx, &diags, "cannot parse date", fmt.Sprintf("cannot parse date %q with format %q: %v", text, format, err))
+		return diags
+	}
+	return diags
+}
+
+// GetTimeFromStringAttribute retrieves a string attribute from e.g. a [plan.Plan], [tfsdk.Config] or a [tfsdk.State] and
+// converts it to a [time.Time] object with a given format, if possible.
+func GetTimeFromStringAttribute(ctx context.Context, attributePath path.Path, source attributeGetter, dateFormat string, target *time.Time) (diags diag.Diagnostics) {
+	var date types.String
+	diags.Append(source.GetAttribute(ctx, attributePath, &date)...)
+	if diags.HasError() {
+		return diags
+	}
+	if date.IsNull() || date.IsUnknown() {
+		return diags
+	}
+	diags.Append(ToTime(ctx, dateFormat, date, target)...)
+	if diags.HasError() {
+		return diags
+	}
+
+	return diags
+}

stackit/internal/utils/attributes_test.go

@@ -0,0 +1,88 @@
+package utils
+
+import (
+	"context"
+	"log"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/terraform-plugin-framework/diag"
+	"github.com/hashicorp/terraform-plugin-framework/path"
+	"github.com/hashicorp/terraform-plugin-framework/types"
+)
+
+type attributeGetterFunc func(ctx context.Context, attributePath path.Path, target interface{}) diag.Diagnostics
+
+func (a attributeGetterFunc) GetAttribute(ctx context.Context, attributePath path.Path, target interface{}) diag.Diagnostics {
+	return a(ctx, attributePath, target)
+}
+
+func mustLocation(name string) *time.Location {
+	loc, err := time.LoadLocation(name)
+	if err != nil {
+		log.Panicf("cannot load location %s: %v", name, err)
+	}
+	return loc
+}
+
+func TestGetTimeFromString(t *testing.T) {
+	type args struct {
+		path       path.Path
+		source     attributeGetterFunc
+		dateFormat string
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+		want    time.Time
+	}{
+		{
+			name: "simple string",
+			args: args{
+				path: path.Root("foo"),
+				source: func(_ context.Context, _ path.Path, target interface{}) diag.Diagnostics {
+					t, ok := target.(*types.String)
+					if !ok {
+						log.Panicf("wrong type %T", target)
+					}
+					*t = types.StringValue("2025-02-06T09:41:00+01:00")
+					return nil
+				},
+				dateFormat: time.RFC3339,
+			},
+			want: time.Date(2025, 2, 6, 9, 41, 0, 0, mustLocation("Europe/Berlin")),
+		},
+		{
+			name: "invalid type",
+			args: args{
+				path: path.Root("foo"),
+				source: func(_ context.Context, p path.Path, _ interface{}) (diags diag.Diagnostics) {
+					diags.AddAttributeError(p, "kapow", "kapow")
+					return diags
+				},
+				dateFormat: time.RFC3339,
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var target time.Time
+			gotDiags := GetTimeFromStringAttribute(context.Background(), tt.args.path, tt.args.source, tt.args.dateFormat, &target)
+			if tt.wantErr {
+				if !gotDiags.HasError() {
+					t.Errorf("expected error")
+				}
+			} else {
+				if gotDiags.HasError() {
+					t.Errorf("expected no errors, but got %v", gotDiags)
+				} else {
+					if want, got := tt.want, target; !want.Equal(got) {
+						t.Errorf("got wrong date, want %s but got %s", want, got)
+					}
+				}
+			}
+		})
+	}
+}