write_stdout.go

/*
 * Copyright (C) 2021 IBM, Inc.
 *
 * 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 write

import (
	"encoding/json"
	"fmt"
	"os"
	"sort"
	"text/tabwriter"
	"time"

	"github.com/netobserv/flowlogs-pipeline/pkg/config"
	"github.com/sirupsen/logrus"
)

type writeStdout struct {
	format string
}

// Write writes a flow before being stored
func (t *writeStdout) Write(v config.GenericMap) {
	logrus.Tracef("entering writeStdout Write")
	if t.format == "json" {
		txt, _ := json.Marshal(v)
		fmt.Println(string(txt))
	} else if t.format == "fields" {
		var order sort.StringSlice
		for fieldName := range v {
			order = append(order, fieldName)
		}
		order.Sort()
		w := tabwriter.NewWriter(os.Stdout, 0, 0, 1, ' ', 0)
		fmt.Fprintf(w, "\n\nFlow record at %s:\n", time.Now().Format(time.StampMilli))
		for _, field := range order {
			fmt.Fprintf(w, "%v\t=\t%v\n", field, v[field])
		}
		w.Flush()
	} else {
		fmt.Printf("%s: %v\n", time.Now().Format(time.StampMilli), v)
	}
}

// NewWriteStdout create a new write
func NewWriteStdout(params config.StageParam) (Writer, error) {
	logrus.Debugf("entering NewWriteStdout")
	writeStdout := &writeStdout{}
	if params.Write != nil && params.Write.Stdout != nil {
		writeStdout.format = params.Write.Stdout.Format
	}
	return writeStdout, nil
}