logsapi/functionlogs.go

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// the Apache License, Version 2.0 (the "License"); you may
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// 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
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// specific language governing permissions and limitations
// under the License.

package logsapi

import (
	"github.com/elastic/apm-aws-lambda/logsapi/model"
	"go.elastic.co/fastjson"
)

// ProcessFunctionLog processes the `function` log line from lambda logs API and returns
// a byte array containing the JSON body for the extracted log along with the timestamp.
// A non nil error is returned when marshaling of the log into JSON fails.
func ProcessFunctionLog(
	requestID string,
	invokedFnArn string,
	log LogEvent,
) ([]byte, error) {
	lc := model.LogContainer{
		Log: &model.LogLine{
			Timestamp: model.Time(log.Time),
			Message:   log.StringRecord,
		},
	}

	lc.Log.FAAS = &model.FAAS{
		ID:        invokedFnArn,
		Execution: requestID,
	}

	var jsonWriter fastjson.Writer
	if err := lc.MarshalFastJSON(&jsonWriter); err != nil {
		return nil, err
	}

	return jsonWriter.Bytes(), nil
}