Testing

log_test.go

package log_test

import (
	"bytes"
	"encoding/json"
	"nomad-datadog-exporter/internal/log"
	"os"
	"testing"

	"github.com/google/go-cmp/cmp"
	"github.com/sirupsen/logrus"
)

type format struct {
	AwsRegion    string `json:"aws_region,omitempty"`
	FunctionName string `json:"function_name,omitempty"`
	Level        string `json:"level,omitempty"`
	Msg          string `json:"msg,omitempty"`
}

func TestNewLoggerDefaults(t *testing.T) {
	t.Parallel()

	os.Setenv("AWS_REGION", "us-east-1")
	os.Setenv("AWS_LAMBDA_FUNCTION_NAME", "nomad-datadog-exporter")

	type testCase struct {
		want  format
		msg   string
		level logrus.Level
		err   error
		eq    bool
	}

	testCases := []testCase{
		{
			want: format{
				AwsRegion:    "us-east-1",
				FunctionName: "nomad-datadog-exporter",
				Level:        "info",
				Msg:          "Test!!!",
			},
			msg:   "Test!!!",
			level: log.Info,
			err:   nil,
			eq:    true,
		},
		{
			want: format{
				AwsRegion:    "us-east-1",
				FunctionName: "nomad-datadog-exporter",
				Level:        "debug",
				Msg:          "Test!!!",
			},
			msg:   "Test!!!",
			level: log.Debug,
			err:   nil,
			eq:    true,
		},
		{
			want: format{
				AwsRegion:    "us-east-1",
				FunctionName: "nomad-datadog-exporter",
				Level:        "info",
				Msg:          "Test!!!",
			},
			msg:   "Test!!!",
			level: log.Info,
			err:   nil,
			eq:    true,
		},
	}

	for _, tc := range testCases {
		fakeStdErr := &bytes.Buffer{}
		logger, err := log.NewLogger(
			log.WithOutput(fakeStdErr),
			log.WithLevel(tc.level),
		)
		if err != tc.err {
			t.Fatal(err)
		}
		switch {
		case tc.level == log.Debug:
			logger.Debug(tc.msg)
		default:
			logger.Info(tc.msg)
		}
		var got format
		if err := json.Unmarshal(fakeStdErr.Bytes(), &got); err != nil {
			t.Fatal(err)
		}
		if cmp.Equal(tc.want, got) != tc.eq {
			t.Error(cmp.Diff(tc.want, got))
		}
	}
}