[WIP] v0.7.0 fixes and changes to cache and remotefetcher

pkg/remotefetcher/s3.go

@@ -0,0 +1,91 @@
+package remotefetcher
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha256"
+	"encoding/hex"
+	"errors"
+	"strings"
+
+	"github.com/aws/aws-sdk-go-v2/config"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/aws/aws-sdk-go-v2/service/s3/types"
+	"gopkg.in/yaml.v3"
+)
+
+type S3Fetcher struct {
+	S3Client *s3.Client
+	config   FetcherConfig
+}
+
+// NewS3Fetcher creates a new instance of S3Fetcher with the provided options.
+func NewS3Fetcher(options ...Option) (*S3Fetcher, error) {
+	cfg := &FetcherConfig{}
+	for _, opt := range options {
+		opt(cfg)
+	}
+
+	// Initialize S3 client if not provided
+	if cfg.S3Client == nil {
+		awsCfg, err := config.LoadDefaultConfig(context.TODO())
+		if err != nil {
+			return nil, err
+		}
+		cfg.S3Client = s3.NewFromConfig(awsCfg)
+	}
+
+	return &S3Fetcher{S3Client: cfg.S3Client, config: *cfg}, nil
+}
+
+// Fetch retrieves the configuration from an S3 bucket
+// Source should be in the format "bucket-name/object-key"
+func (s *S3Fetcher) Fetch(source string) ([]byte, error) {
+	bucket, key, err := parseS3Source(source)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := s.S3Client.GetObject(context.TODO(), &s3.GetObjectInput{
+		Bucket: &bucket,
+		Key:    &key,
+	})
+	if err != nil {
+		if err != nil {
+			var notFound *types.NoSuchKey
+			if errors.As(err, &notFound) && s.config.IgnoreFileNotFound {
+				return nil, ErrFileNotFound
+			}
+			return nil, err
+		}
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	buf := new(bytes.Buffer)
+	_, err = buf.ReadFrom(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+// Parse decodes the raw data into the provided target structure
+func (s *S3Fetcher) Parse(data []byte, target interface{}) error {
+	return yaml.Unmarshal(data, target)
+}
+
+// Helper function to parse S3 source into bucket and key
+func parseS3Source(source string) (bucket, key string, err error) {
+	parts := strings.SplitN(source, "/", 2)
+	if len(parts) != 2 {
+		return "", "", errors.New("invalid S3 source format, expected bucket-name/object-key")
+	}
+	return parts[0], parts[1], nil
+}
+
+func (s *S3Fetcher) Hash(data []byte) string {
+	hash := sha256.Sum256(data)
+	return hex.EncodeToString(hash[:])
+}