v0.0.29

2022-12-07 23:15:16 +01:00
parent 6a304b875a
commit 2c69b33547
2 changed files with 222 additions and 0 deletions
--- a/timeext/parser.go
+++ b/timeext/parser.go
@@ -0,0 +1,152 @@
+package timeext
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var durationShortStringMap = map[string]time.Duration{
+	"ns":          time.Nanosecond,
+	"nanosecond":  time.Nanosecond,
+	"nanoseconds": time.Nanosecond,
+
+	"us":           time.Microsecond,
+	"microsecond":  time.Microsecond,
+	"microseconds": time.Microsecond,
+
+	"ms":           time.Millisecond,
+	"millisecond":  time.Millisecond,
+	"milliseconds": time.Millisecond,
+
+	"s":       time.Second,
+	"sec":     time.Second,
+	"second":  time.Second,
+	"seconds": time.Second,
+
+	"m":       time.Minute,
+	"min":     time.Minute,
+	"minute":  time.Minute,
+	"minutes": time.Minute,
+
+	"h":     time.Hour,
+	"hour":  time.Hour,
+	"hours": time.Hour,
+
+	"d":    24 * time.Hour,
+	"day":  24 * time.Hour,
+	"days": 24 * time.Hour,
+
+	"w":     7 * 24 * time.Hour,
+	"wk":    7 * 24 * time.Hour,
+	"week":  7 * 24 * time.Hour,
+	"weeks": 7 * 24 * time.Hour,
+}
+
+// ParseDurationShortString parses a duration in string format to a time.Duration
+// Examples for allowed formats:
+//   - '10m'
+//   - '10min'
+//   - '1minute'
+//   - '10minutes'
+//   - '10.5minutes'
+//   - '50s'
+//   - '50sec'
+//   - '1second'
+//   - '50seconds'
+//   - '100ms'
+//   - '100millisseconds'
+//   - '1h'
+//   - '1hour'
+//   - '2hours'
+//   - '1d'
+//   - '1day'
+//   - '10days'
+//   - '1d10m'
+//   - '1d10m200sec'
+//   - '1d:10m'
+//   - '1d 10m'
+//   - '1d,10m'
+func ParseDurationShortString(s string) (time.Duration, error) {
+	s = strings.ToLower(s)
+
+	segments := make([]string, 0)
+	collector := ""
+
+	prevWasNum := true
+	for _, chr := range s {
+		if chr >= '0' && chr <= '9' || chr == '.' {
+			if prevWasNum {
+				collector += string(chr)
+			} else {
+				segments = append(segments, collector)
+				prevWasNum = true
+				collector = string(chr)
+			}
+		} else if chr == ' ' || chr == ':' || chr == ',' {
+			continue
+		} else if chr >= 'a' && chr <= 'z' {
+			prevWasNum = false
+			collector += string(chr)
+		} else {
+			return 0, errors.New("unexpected character: " + string(chr))
+		}
+	}
+	if !prevWasNum {
+		segments = append(segments, collector)
+	}
+
+	result := time.Duration(0)
+	for _, seg := range segments {
+		segDur, err := parseDurationShortStringSegment(seg)
+		if err != nil {
+			return 0, err
+		}
+		result += segDur
+	}
+	return result, nil
+}
+
+func parseDurationShortStringSegment(segment string) (time.Duration, error) {
+	num := ""
+	unit := ""
+
+	part0 := true
+	for _, chr := range segment {
+		if part0 {
+
+			if chr >= 'a' && chr <= 'z' {
+				part0 = false
+				unit += string(chr)
+			} else if chr >= '0' && chr <= '9' || chr == '.' {
+				num += string(chr)
+			} else {
+				return 0, errors.New(fmt.Sprintf("Unexpected character '%s' in segment [%s]", string(chr), segment))
+			}
+
+		} else {
+
+			if chr >= 'a' && chr <= 'z' {
+				unit += string(chr)
+			} else if chr >= '0' && chr <= '9' || chr == '.' {
+				return 0, errors.New(fmt.Sprintf("Unexpected number '%s' in segment [%s]", string(chr), segment))
+			} else {
+				return 0, errors.New(fmt.Sprintf("Unexpected character '%s' in segment [%s]", string(chr), segment))
+			}
+
+		}
+	}
+
+	fpnum, err := strconv.ParseFloat(num, 64)
+	if err != nil {
+		return 0, errors.New(fmt.Sprintf("Failed to parse floating-point number '%s' in segment [%s]", num, segment))
+	}
+
+	if mult, ok := durationShortStringMap[unit]; ok {
+		return time.Duration(int64(fpnum * float64(mult))), nil
+	} else {
+		return 0, errors.New(fmt.Sprintf("Unknown unit '%s' in segment [%s]", unit, segment))
+	}
+}