kataras/iris · error

%s: %w

Error message

%s: %w

What it means

ParseSimpleDate tries "2006-01-02" first; if that fails it retries the zero-padded-optional Postgres layout "2006-1-2" (pgx v5.0.0-alpha.3+ returns dates like "1993-1-1"). If both parses fail, it returns the second error's text followed by the first error, as "<parse2 error>: <parse1 error>".

Source

Thrown at x/jsonx/simple_date.go:53

//   - "2024-1-1"
func ParseSimpleDate(s string) (SimpleDate, error) {
	if s == "" || s == "null" {
		return SimpleDate{}, nil
	}

	var (
		tt  time.Time
		err error
	)

	tt, err = time.Parse(SimpleDateLayout, s)
	if err != nil {
		// After v5.0.0-alpha.3 of pgx this is coming as "1993-1-1" instead of the stored
		// value "1993-01-01".
		var err2 error
		tt, err2 = time.Parse(simpleDateLayoutPostgres, s)
		if err2 != nil {
			return SimpleDate{}, fmt.Errorf("%s: %w", err2.Error(), err)
		}
	}

	return SimpleDate(tt), nil
}

// UnmarshalJSON binds the json "data" to "t" with the `SimpleDateLayout`.
func (t *SimpleDate) UnmarshalJSON(data []byte) error {
	if isNull(data) {
		return nil
	}

	data = trimQuotes(data)
	dataStr := string(data)
	if len(dataStr) == 0 {
		return nil // do not allow empty "" on simple dates.
	}

View on GitHub (pinned to 7bedaf55a0)

Solutions

1. Normalize the input to YYYY-MM-DD before calling ParseSimpleDate.
2. If it comes from a full timestamp, truncate: t.Format("2006-01-02") first.
3. Use time.Parse with your custom layout and then convert via jsonx.SimpleDateFromTime(t).

Example fix

// before
jsonx.ParseSimpleDate("01/02/1993") // error
// after
t, _ := time.Parse("02/01/2006", "01/02/1993")
sd := jsonx.SimpleDateFromTime(t)

func isSimpleDateLayout(s string) bool {
	_, e1 := time.Parse("2006-01-02", s)
	_, e2 := time.Parse("2006-1-2", s)
	return e1 == nil || e2 == nil
}

func toSimpleDate(s string) (jsonx.SimpleDate, error) {
	for _, layout := range []string{"2006-01-02", "2006-1-2", "02/01/2006", "01/02/2006"} {
		if t, err := time.Parse(layout, s); err == nil {
			return jsonx.SimpleDateFromTime(t), nil
		}
	}
	return jsonx.SimpleDate{}, fmt.Errorf("unsupported date format: %s", s)
}

sd, err := jsonx.ParseSimpleDate(s)
if err != nil {
	// err text contains both layout failures; log s and fall back to manual layouts
	return fmt.Errorf("parse simple date %q: %w", s, err)
}

When it happens

Trigger: Calling jsonx.ParseSimpleDate (directly or via Scan/UnmarshalJSON paths) with a string that matches neither layout — e.g. "01/02/1993", "1993-01-01 10:00", "Jan 2 2006", or non-date text.

Common situations: Reading date strings from CSV/config in a locale format (DD/MM/YYYY); DB columns typed VARCHAR containing datetime strings; passing a full RFC3339 timestamp instead of a bare date.

Related errors

• kitchen time: convert to time notation first: %w
• KitchenTime: unknown type of: %T
• SimpleDate: unknown type of: %T
• simple dates: scan: invalid type of: %T
• %w: example: %s

AI-assisted analysis of kataras/iris@7bedaf55a0 (2026-08-30). Data as JSON: /api/errors/37b8eaef6aa34fa3. Report an issue: GitHub.