Add float64 field type support

Signed-off-by: Knut Ahlers <knut@ahlers.me>

fieldcollection/schema.go

@@ -37,6 +37,7 @@ const (
 	SchemaFieldTypeAny SchemaFieldType = iota
 	SchemaFieldTypeBool
 	SchemaFieldTypeDuration
+	SchemaFieldTypeFloat64
 	SchemaFieldTypeInt64
 	SchemaFieldTypeString
 	SchemaFieldTypeStringSlice
@@ -110,7 +111,7 @@ func (f *FieldCollection) ValidateSchema(opts ...ValidateOpt) error {
 	return nil
 }
 
-//nolint:gocyclo // These are quite simple checks
+//nolint:gocognit,gocyclo // These are quite simple checks
 func validateFieldType(f *FieldCollection, field SchemaField) (err error) {
 	switch field.Type {
 	case SchemaFieldTypeAny:
@@ -138,6 +139,16 @@ func validateFieldType(f *FieldCollection, field SchemaField) (err error) {
 			return fmt.Errorf("field %s is empty", field.Name)
 		}
 
+	case SchemaFieldTypeFloat64:
+		v, err := f.Float64(field.Name)
+		if err != nil {
+			return fmt.Errorf("field %s is not of type float64: %w", field.Name, err)
+		}
+
+		if field.NonEmpty && v == 0 {
+			return fmt.Errorf("field %s is empty", field.Name)
+		}
+
 	case SchemaFieldTypeInt64:
 		v, err := f.Int64(field.Name)
 		if err != nil {

fieldcollection/typeFloat.go

@@ -0,0 +1,67 @@
+package fieldcollection
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/pkg/errors"
+)
+
+// Float64 tries to read key name as float64
+func (f *FieldCollection) Float64(name string) (float64, error) {
+	if f == nil || f.data == nil {
+		return 0, errors.New("uninitialized field collection")
+	}
+
+	f.lock.RLock()
+	defer f.lock.RUnlock()
+
+	v, ok := f.data[name]
+	if !ok {
+		return 0, ErrValueNotSet
+	}
+
+	switch v := v.(type) {
+	case int:
+		return float64(v), nil
+
+	case int16:
+		return float64(v), nil
+
+	case int32:
+		return float64(v), nil
+
+	case int64:
+		return float64(v), nil
+
+	case float64:
+		return v, nil
+
+	case string:
+		pv, err := strconv.ParseFloat(v, 64)
+		if err != nil {
+			return 0, fmt.Errorf("parsing value: %w", err)
+		}
+		return pv, nil
+	}
+
+	return 0, ErrValueMismatch
+}
+
+// CanFloat64 tries to read key name as float64 and checks whether error is nil
+func (f *FieldCollection) CanFloat64(name string) bool {
+	_, err := f.Float64(name)
+	return err == nil
+}
+
+// MustFloat64 is a wrapper around Float64 and panics if an error was returned
+func (f *FieldCollection) MustFloat64(name string, defVal *float64) float64 {
+	v, err := f.Float64(name)
+	if err != nil {
+		if defVal != nil {
+			return *defVal
+		}
+		panic(err)
+	}
+	return v
+}

fieldcollection/typeFloat_test.go

@@ -0,0 +1,57 @@
+package fieldcollection
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFloat64(t *testing.T) {
+	fc := FieldCollectionFromData(map[string]any{
+		"int":           int(12),
+		"int16":         int16(12),
+		"int32":         int32(12),
+		"int64":         int64(12),
+		"float64":       float64(12),
+		"bool":          true,
+		"invalidString": "I'm a string!",
+		"validString":   "12",
+	})
+
+	_, err := fc.Float64("_")
+	assert.ErrorIs(t, err, ErrValueNotSet)
+
+	_, err = fc.Float64("bool")
+	assert.ErrorIs(t, err, ErrValueMismatch)
+
+	_, err = fc.Float64("invalidString")
+	assert.Error(t, err)
+
+	v, err := fc.Float64("int")
+	assert.NoError(t, err)
+	assert.Equal(t, float64(12), v)
+
+	v, err = fc.Float64("int16")
+	assert.NoError(t, err)
+	assert.Equal(t, float64(12), v)
+
+	v, err = fc.Float64("int32")
+	assert.NoError(t, err)
+	assert.Equal(t, float64(12), v)
+
+	v, err = fc.Float64("int64")
+	assert.NoError(t, err)
+	assert.Equal(t, float64(12), v)
+
+	v, err = fc.Float64("validString")
+	assert.NoError(t, err)
+	assert.Equal(t, float64(12), v)
+
+	assert.True(t, fc.CanFloat64("int"))
+	assert.False(t, fc.CanFloat64("bool"))
+
+	assert.NotPanics(t, func() { fc.MustFloat64("int32", nil) })
+	assert.Panics(t, func() { fc.MustFloat64("bool", nil) })
+
+	assert.Equal(t, float64(5), fc.MustFloat64("_", func(v float64) *float64 { return &v }(5)))
+}