store: implement s3 blob store (#2005)

store/s3/s3.go

@@ -0,0 +1,149 @@
+package s3
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/micro/go-micro/v3/store"
+	"github.com/minio/minio-go/v7"
+	"github.com/minio/minio-go/v7/pkg/credentials"
+	"github.com/pkg/errors"
+)
+
+// NewBlobStore returns an initialized s3 blob store
+func NewBlobStore(opts ...Option) (store.BlobStore, error) {
+	// parse the options
+	options := Options{Secure: true}
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// initialize minio client
+	client, err := minio.New(options.Endpoint, &minio.Options{
+		Creds:  credentials.NewStaticV4(options.AccessKeyID, options.SecretAccessKey, ""),
+		Secure: options.Secure,
+	})
+	if err != nil {
+		return nil, errors.Wrap(err, "Error connecting to s3 blob store")
+	}
+
+	// return the blob store
+	return &s3{client, &options}, nil
+}
+
+type s3 struct {
+	client  *minio.Client
+	options *Options
+}
+
+func (s *s3) Read(key string, opts ...store.BlobOption) (io.Reader, error) {
+	// validate the key
+	if len(key) == 0 {
+		return nil, store.ErrMissingKey
+	}
+
+	// parse the options
+	var options store.BlobOptions
+	for _, o := range opts {
+		o(&options)
+	}
+	if len(options.Namespace) == 0 {
+		options.Namespace = "micro"
+	}
+
+	// lookup the object
+	res, err := s.client.GetObject(
+		context.TODO(),           // context
+		options.Namespace,        // bucket name
+		key,                      // object name
+		minio.GetObjectOptions{}, // options
+	)
+
+	// scaleway will return a 404 if the bucket doesn't exist
+	if verr, ok := err.(minio.ErrorResponse); ok && verr.StatusCode == http.StatusNotFound {
+		return nil, store.ErrNotFound
+	} else if err != nil {
+		return nil, err
+	}
+
+	// check the object info, if an error is returned the object could not be found
+	_, err = res.Stat()
+	if verr, ok := err.(minio.ErrorResponse); ok && verr.StatusCode == http.StatusNotFound {
+		return nil, store.ErrNotFound
+	} else if err != nil {
+		return nil, err
+	}
+
+	// return the result
+	return res, nil
+}
+
+func (s *s3) Write(key string, blob io.Reader, opts ...store.BlobOption) error {
+	// validate the key
+	if len(key) == 0 {
+		return store.ErrMissingKey
+	}
+
+	// parse the options
+	var options store.BlobOptions
+	for _, o := range opts {
+		o(&options)
+	}
+	if len(options.Namespace) == 0 {
+		options.Namespace = "micro"
+	}
+
+	// check the bucket exists, create it if not
+	if exists, err := s.client.BucketExists(context.TODO(), options.Namespace); err != nil {
+		return err
+	} else if !exists {
+		opts := minio.MakeBucketOptions{Region: s.options.Region}
+		if err := s.client.MakeBucket(context.TODO(), options.Namespace, opts); err != nil {
+			return err
+		}
+	}
+
+	// get the bytes so we can determine the length
+	b, err := ioutil.ReadAll(blob)
+	if err != nil {
+		return err
+	}
+
+	// create the object in the bucket
+	_, err = s.client.PutObject(
+		context.TODO(),           // context
+		options.Namespace,        // bucket name
+		key,                      // object name
+		bytes.NewBuffer(b),       // reader
+		int64(len(b)),            // length of object
+		minio.PutObjectOptions{}, // options
+	)
+	return err
+}
+
+func (s *s3) Delete(key string, opts ...store.BlobOption) error {
+	// validate the key
+	if len(key) == 0 {
+		return store.ErrMissingKey
+	}
+
+	// parse the options
+	var options store.BlobOptions
+	for _, o := range opts {
+		o(&options)
+	}
+	if len(options.Namespace) == 0 {
+		options.Namespace = "micro"
+	}
+
+	err := s.client.RemoveObject(
+		context.TODO(),              // context
+		options.Namespace,           // bucket name
+		key,                         // object name
+		minio.RemoveObjectOptions{}, // options
+	)
+	return err
+}