Golang : Convert an image file to []byte
This is a quick tutorial on how to convert an image file to byte array. This question was originally posted to me via email at admin@socketloop.com by Mr. Aung.
Basically, Mr. Aung would like to know how to turn an image file into a byte array ( []byte )
and the answer is :
fileToBeUploaded := "image.jpg"
file, err := os.Open(fileToBeUploaded)
if err != nil {
fmt.Println(err)
os.Exit(1)
}
defer file.Close()
fileInfo, _ := file.Stat()
var size int64 = fileInfo.Size()
bytes := make([]byte, size)
// read file into bytes
buffer := bufio.NewReader(file)
_, err = buffer.Read(bytes) // <--------------- here!
// then we need to determine the file type
// see https://www.socketloop.com/tutorials/golang-how-to-verify-uploaded-file-is-image-or-allowed-file-types
filetype := http.DetectContentType(bytes)
err = bucket.Put(path, bytes, filetype, s3.ACL("public-read"))
the code fragment is taken from https://www.socketloop.com/tutorials/golang-upload-and-download-file-to-from-aws-s3
See also : Golang : Upload and download file to/from AWS S3
By Adam Ng
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