weather/internal/storage/s3.go

package storage

import (
	"context"
	"fmt"
	"go/weather/pkg/logger"
	"io"
	"time"

	"github.com/minio/minio-go/v7"
	"github.com/minio/minio-go/v7/pkg/credentials"
	"go.elastic.co/apm"
	"go.elastic.co/apm/module/apmzap"
	"go.uber.org/zap"
)

//AwsDefaultSection toml default section
type AwsDefaultSection struct {
	// attribute should be public ! for go-toml
	EndpointURL string `hcl:"endpoint_url"`
	BucketName  string `hcl:"bucket_name"`
}

//WeatherS3StorageConfig interface abstracting storageConfig
type WeatherS3StorageConfig struct {
	AwsDefaultSection  `hcl:",nested"`
	Region             string `hcl:"region"`
	AwsAccessKeyID     string `hcl:"aws_access_key_id"`
	AwsSecretAccessKey string `hcl:"aws_secret_access_key"`
}

//s3Storage classe used to store oi.Reader to s3
type S3Storage struct {
	logger   *logger.WeatherLogger
	Session  *minio.Client
	S3Config *WeatherS3StorageConfig
}

//NewS3Storage instanciate storage object
func NewS3Storage(log *logger.WeatherLogger, config *WeatherS3StorageConfig) *S3Storage {
	s3 := S3Storage{
		logger:   log,
		S3Config: config,
	}
	var err error

	// Initialize minio client object.
	s3.Session, err = minio.New(config.EndpointURL, &minio.Options{
		Region: config.Region,
		Creds:  credentials.NewStaticV4(config.AwsAccessKeyID, config.AwsSecretAccessKey, ""),
		Secure: false,
	})
	if err != nil {
		s3.logger.Fatal("Storage error", zap.Error(err))
	}

	return &s3
}

//Store send data to s3 bucket
func (ss *S3Storage) Store(ctx context.Context, content io.Reader) {
	span, ctx := apm.StartSpan(ctx, "s3StoreWeatherInfo", "custom")
	defer span.End()

	name := fmt.Sprintf("%s.json", time.Now().UTC().Format(time.RFC3339))

	_, err := ss.Session.PutObject(ctx, ss.S3Config.BucketName, name, content, -1, minio.PutObjectOptions{
		ContentType: "application/json",
	})
	if err != nil {
		ss.logger.Error("Storage error", zap.Error(err))
	} else {
		ss.logger.Debug("Storage success", apmzap.TraceContext(ctx)...)
	}
}

//GetAtDate retrieve one data from bucket
func (ss *S3Storage) GetAtDate(ctx context.Context, atDate time.Time) *minio.Object {
	filename := fmt.Sprintf("%s.json", atDate.Format(time.RFC3339))
	reader, err := ss.Session.GetObject(ctx, ss.S3Config.BucketName, filename, minio.GetObjectOptions{})
	if err != nil {
		ss.logger.Error("Storage get s3Object failed", zap.Error(err))
		return nil
	}
	return reader
}

type Streamable interface{}

type WeatherFile struct {
	Streamable `json:"-"`
	Name       string `json:"name"`
}

//GetAll list all date available
func (ss *S3Storage) GetAll(ctx context.Context) <-chan Streamable {
	// []string
	objectStatCh := make(chan Streamable, 1)

	go func() {
		for object := range ss.Session.ListObjects(ctx, ss.S3Config.BucketName, minio.ListObjectsOptions{}) {
			if object.Err != nil {
				fmt.Println(object.Err)
				continue
			}
			objectStatCh <- WeatherFile{Name: object.Key}
		}
	}()
	return objectStatCh
}