initial commit of library & tests

cast.go

@@ -0,0 +1,48 @@
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package cast
+
+import "time"
+
+func ToBool(i interface{}) bool {
+	v, _ := ToBoolE(i)
+	return v
+}
+
+func ToTime(i interface{}) time.Time {
+	v, _ := ToTimeE(i)
+	return v
+}
+
+func ToFloat64(i interface{}) float64 {
+	v, _ := ToFloat64E(i)
+	return v
+}
+
+func ToInt(i interface{}) int {
+	v, _ := ToIntE(i)
+	return v
+}
+
+func ToString(i interface{}) string {
+	v, _ := ToStringE(i)
+	return v
+}
+
+func ToStringMapString(i interface{}) map[string]string {
+	v, _ := ToStringMapStringE(i)
+	return v
+}
+
+func ToStringMap(i interface{}) map[string]interface{} {
+	v, _ := ToStringMapE(i)
+	return v
+}
+
+func ToStringSlice(i interface{}) []string {
+	v, _ := ToStringSliceE(i)
+	return v
+}

cast_test.go

@@ -0,0 +1,26 @@
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package cast
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestToInt(t *testing.T) {
+	var eight interface{} = 8
+	assert.Equal(t, ToInt(8), 8)
+	assert.Equal(t, ToInt("8"), 8)
+	assert.Equal(t, ToInt(true), 1)
+	assert.Equal(t, ToInt(false), 0)
+	assert.Equal(t, ToInt(eight), 8)
+}
+
+func TestMaps(t *testing.T) {
+	var taxonomies = map[interface{}]interface{}{"tag": "tags", "group": "groups"}
+	assert.Equal(t, ToStringMap(taxonomies), map[string]interface{}{"tag": "tags", "group": "groups"})
+}

caste.go

@@ -0,0 +1,199 @@
+// Copyright © 2014 Steve Francia <spf@spf13.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+package cast
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"time"
+
+	jww "github.com/spf13/jwalterweatherman"
+)
+
+func ToTimeE(i interface{}) (tim time.Time, ok bool) {
+	switch s := i.(type) {
+	case time.Time:
+		return s, true
+	case string:
+		d, e := StringToDate(s)
+		if e == nil {
+			return d, true
+		}
+
+		jww.ERROR.Println("Could not parse Date/Time format:", e)
+		return time.Time{}, false
+	default:
+		jww.ERROR.Printf("Unable to Cast %#v to Time", i)
+		return time.Time{}, false
+	}
+
+	return time.Time{}, false
+}
+
+func ToBoolE(i interface{}) (bool, bool) {
+	switch b := i.(type) {
+	case bool:
+		return b, true
+	case nil:
+		return false, true
+	case int:
+		if i.(int) > 0 {
+			return true, true
+		}
+		return false, true
+	default:
+		return false, false
+		jww.ERROR.Printf("Unable to Cast %#v to bool", i)
+	}
+
+	return false, false
+}
+
+func ToStringMapStringE(i interface{}) (map[string]string, bool) {
+	var m = map[string]string{}
+
+	switch v := i.(type) {
+	case map[interface{}]interface{}:
+		for k, val := range v {
+			m[ToString(k)] = ToString(val)
+		}
+	default:
+		return m, false
+	}
+
+	return m, true
+}
+
+func ToStringMapE(i interface{}) (map[string]interface{}, bool) {
+	var m = map[string]interface{}{}
+
+	switch v := i.(type) {
+	case map[interface{}]interface{}:
+		for k, val := range v {
+			m[ToString(k)] = val
+		}
+	default:
+		return m, false
+	}
+
+	return m, true
+}
+
+func ToStringSliceE(i interface{}) ([]string, bool) {
+	var a []string
+
+	switch v := i.(type) {
+	case []interface{}:
+		for _, u := range v {
+			a = append(a, ToString(u))
+		}
+	default:
+		return a, false
+	}
+
+	return a, true
+}
+
+func ToFloat64E(i interface{}) (float64, bool) {
+	switch s := i.(type) {
+	case float64:
+		return s, true
+	case float32:
+		return float64(s), true
+
+	case string:
+		v, err := strconv.ParseFloat(s, 64)
+		if err == nil {
+			return float64(v), true
+		} else {
+			jww.ERROR.Printf("Unable to Cast %#v to float", i)
+			jww.ERROR.Println(err)
+		}
+
+	default:
+		jww.ERROR.Printf("Unable to Cast %#v to float", i)
+	}
+
+	return 0.0, false
+}
+
+func ToIntE(i interface{}) (int, bool) {
+	switch s := i.(type) {
+	case int:
+		return s, true
+	case int64:
+		return int(s), true
+	case int32:
+		return int(s), true
+	case int16:
+		return int(s), true
+	case int8:
+		return int(s), true
+	case string:
+		v, err := strconv.ParseInt(s, 0, 0)
+		if err == nil {
+			return int(v), true
+		} else {
+			jww.ERROR.Printf("Unable to Cast %#v to int", i)
+			jww.ERROR.Println(err)
+		}
+	case bool:
+		if bool(s) {
+			return 1, true
+		} else {
+			return 0, true
+		}
+	default:
+		jww.ERROR.Printf("Unable to Cast %#v to int", i)
+	}
+
+	return 0, false
+}
+
+func ToStringE(i interface{}) (string, bool) {
+	switch s := i.(type) {
+	case string:
+		return s, true
+	case float64:
+		return strconv.FormatFloat(i.(float64), 'f', -1, 64), true
+	case int:
+		return strconv.FormatInt(int64(i.(int)), 10), true
+	case nil:
+		return "", true
+	default:
+		jww.ERROR.Printf("Unable to Cast %#v to string", i)
+	}
+
+	return "", false
+}
+
+func StringToDate(s string) (time.Time, error) {
+	return parseDateWith(s, []string{
+		time.RFC3339,
+		"2006-01-02T15:04:05", // iso8601 without timezone
+		time.RFC1123Z,
+		time.RFC1123,
+		time.RFC822Z,
+		time.RFC822,
+		time.ANSIC,
+		time.UnixDate,
+		time.RubyDate,
+		"2006-01-02 15:04:05Z07:00",
+		"02 Jan 06 15:04 MST",
+		"2006-01-02",
+		"02 Jan 2006",
+	})
+}
+
+func parseDateWith(s string, dates []string) (d time.Time, e error) {
+	for _, dateType := range dates {
+		if d, e = time.Parse(dateType, s); e == nil {
+			return
+		}
+	}
+	return d, errors.New(fmt.Sprintf("Unable to parse date: %s", s))
+}