util.go•4.94 kB
// Copyright 2025 Google LLC
//
// 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 util
import (
"bytes"
"context"
"encoding/json"
"fmt"
"io"
"strings"
"github.com/go-playground/validator/v10"
yaml "github.com/goccy/go-yaml"
"github.com/googleapis/genai-toolbox/internal/log"
"github.com/googleapis/genai-toolbox/internal/telemetry"
)
// DecodeJSON decodes a given reader into an interface using the json decoder.
func DecodeJSON(r io.Reader, v interface{}) error {
defer io.Copy(io.Discard, r) //nolint:errcheck
d := json.NewDecoder(r)
// specify JSON numbers should get parsed to json.Number instead of float64 by default.
// This prevents loss between floats/ints.
d.UseNumber()
return d.Decode(v)
}
// ConvertNumbers traverses an interface and converts all json.Number
// instances to int64 or float64.
func ConvertNumbers(data any) (any, error) {
switch v := data.(type) {
// If it's a map, recursively convert the values.
case map[string]any:
for key, val := range v {
convertedVal, err := ConvertNumbers(val)
if err != nil {
return nil, err
}
v[key] = convertedVal
}
return v, nil
// If it's a slice, recursively convert the elements.
case []any:
for i, val := range v {
convertedVal, err := ConvertNumbers(val)
if err != nil {
return nil, err
}
v[i] = convertedVal
}
return v, nil
// If it's a json.Number, convert it to float or int
case json.Number:
// Check for a decimal point to decide the type.
if strings.Contains(v.String(), ".") {
return v.Float64()
}
return v.Int64()
// For all other types, return them as is.
default:
return data, nil
}
}
var _ yaml.InterfaceUnmarshalerContext = &DelayedUnmarshaler{}
// DelayedUnmarshaler is struct that saves the provided unmarshal function
// passed to UnmarshalYAML so it can be re-used later once the target interface
// is known.
type DelayedUnmarshaler struct {
unmarshal func(interface{}) error
}
func (d *DelayedUnmarshaler) UnmarshalYAML(ctx context.Context, unmarshal func(interface{}) error) error {
d.unmarshal = unmarshal
return nil
}
func (d *DelayedUnmarshaler) Unmarshal(v interface{}) error {
if d.unmarshal == nil {
return fmt.Errorf("nothing to unmarshal")
}
return d.unmarshal(v)
}
type contextKey string
// userAgentKey is the key used to store userAgent within context
const userAgentKey contextKey = "userAgent"
// WithUserAgent adds a user agent into the context as a value
func WithUserAgent(ctx context.Context, versionString string) context.Context {
userAgent := "genai-toolbox/" + versionString
return context.WithValue(ctx, userAgentKey, userAgent)
}
// UserAgentFromContext retrieves the user agent or return an error
func UserAgentFromContext(ctx context.Context) (string, error) {
if ua := ctx.Value(userAgentKey); ua != nil {
return ua.(string), nil
} else {
return "", fmt.Errorf("unable to retrieve user agent")
}
}
func NewStrictDecoder(v interface{}) (*yaml.Decoder, error) {
b, err := yaml.Marshal(v)
if err != nil {
return nil, fmt.Errorf("fail to marshal %q: %w", v, err)
}
dec := yaml.NewDecoder(
bytes.NewReader(b),
yaml.Strict(),
yaml.Validator(validator.New()),
)
return dec, nil
}
// loggerKey is the key used to store logger within context
const loggerKey contextKey = "logger"
// WithLogger adds a logger into the context as a value
func WithLogger(ctx context.Context, logger log.Logger) context.Context {
return context.WithValue(ctx, loggerKey, logger)
}
// LoggerFromContext retrieves the logger or return an error
func LoggerFromContext(ctx context.Context) (log.Logger, error) {
if logger, ok := ctx.Value(loggerKey).(log.Logger); ok {
return logger, nil
}
return nil, fmt.Errorf("unable to retrieve logger")
}
const instrumentationKey contextKey = "instrumentation"
// WithInstrumentation adds an instrumentation into the context as a value
func WithInstrumentation(ctx context.Context, instrumentation *telemetry.Instrumentation) context.Context {
return context.WithValue(ctx, instrumentationKey, instrumentation)
}
// InstrumentationFromContext retrieves the instrumentation or return an error
func InstrumentationFromContext(ctx context.Context) (*telemetry.Instrumentation, error) {
if instrumentation, ok := ctx.Value(instrumentationKey).(*telemetry.Instrumentation); ok {
return instrumentation, nil
}
return nil, fmt.Errorf("unable to retrieve instrumentation")
}