Storage

The storage package selects the provider from CLOUD: aws uses Amazon S3 through the AWS SDK for Go v2, with multipart upload and download of large objects, while gcp and firebase use Google Cloud Storage.

Initialize

Configure credentials through the provider's standard mechanism, then:

colibri.InitializeApp()
storage.Initialize()

CLOUD=none does not create a storage provider.

Upload a form file

In v0.2.6, UploadFile receives *multipart.File:

file, header, err := ctx.FormFile("file")
if err != nil {
	ctx.ErrorResponse(http.StatusBadRequest, err)
	return
}
defer file.Close()

location, err := storage.UploadFile(
	ctx.Context(),
	"documents",
	header.Filename,
	&file,
)

Download and remove

file, err := storage.DownloadFile(ctx, "documents", objectKey)
if err != nil {
	return err
}
defer file.Close()

content, err := io.ReadAll(file)

The returned value is a temporary *os.File; always close it.

err := storage.DeleteFile(ctx, "documents", objectKey)

The v0.2.6 upload API does not accept a generic reader. The bucket must already exist, and the application identity needs permission for each operation.

Metrics

With metrics enabled, each operation records storage.operation and storage.operation.duration, with the operation (upload, download, or delete) and result attributes, and storage.transferred, with the size of uploaded and downloaded files in bytes. Object keys and buckets never become metric attributes.