opentelemetry-collector/component/identifiable.go

104 lines
3.1 KiB
Go

// Copyright The OpenTelemetry Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package component // import "go.opentelemetry.io/collector/component"
import (
"errors"
"fmt"
"strings"
)
// typeAndNameSeparator is the separator that is used between type and name in type/name composite keys.
const typeAndNameSeparator = "/"
// identifiable is an interface that all components configurations MUST embed.
type identifiable interface {
// ID returns the ID of the component that this configuration belongs to.
ID() ID
// SetIDName updates the name part of the ID for the component that this configuration belongs to.
SetIDName(idName string)
}
// ID represents the identity for a component. It combines two values:
// * type - the Type of the component.
// * name - the name of that component.
// The component ID (combination type + name) is unique for a given component.Kind.
type ID struct {
typeVal Type `mapstructure:"-"`
nameVal string `mapstructure:"-"`
}
// NewID returns a new ID with the given Type and empty name.
func NewID(typeVal Type) ID {
return ID{typeVal: typeVal}
}
// NewIDWithName returns a new ID with the given Type and name.
func NewIDWithName(typeVal Type, nameVal string) ID {
return ID{typeVal: typeVal, nameVal: nameVal}
}
// Type returns the type of the component.
func (id ID) Type() Type {
return id.typeVal
}
// Name returns the custom name of the component.
func (id ID) Name() string {
return id.nameVal
}
// MarshalText implements the encoding.TextMarshaler interface.
// This marshals the type and name as one string in the config.
func (id ID) MarshalText() (text []byte, err error) {
return []byte(id.String()), nil
}
// UnmarshalText implements the encoding.TextUnmarshaler interface.
func (id *ID) UnmarshalText(text []byte) error {
idStr := string(text)
items := strings.SplitN(idStr, typeAndNameSeparator, 2)
if len(items) >= 1 {
id.typeVal = Type(strings.TrimSpace(items[0]))
}
if len(items) == 1 && id.typeVal == "" {
return errors.New("id must not be empty")
}
if id.typeVal == "" {
return fmt.Errorf("in %q id: the part before %s should not be empty", idStr, typeAndNameSeparator)
}
if len(items) > 1 {
// "name" part is present.
id.nameVal = strings.TrimSpace(items[1])
if id.nameVal == "" {
return fmt.Errorf("in %q id: the part after %s should not be empty", idStr, typeAndNameSeparator)
}
}
return nil
}
// String returns the ID string representation as "type[/name]" format.
func (id ID) String() string {
if id.nameVal == "" {
return string(id.typeVal)
}
return string(id.typeVal) + typeAndNameSeparator + id.nameVal
}