Could you provide a full S3 example

[christopheblin]

Hi,

I am trying to use your library to upload an object to S3 without the big fat aws-sdk-java jar

However, I dont get how you obtain the

String contentSha256 = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855";

And I also dont get what is x-amz-date which is not described in https://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html

Can you help ?

Here is how my code is looking (this is kotlin without any dependency but your lib)

class S3FileStorage(val accessKey: String, val secretKey: String, val bucket: String) : FileStorage {
    override fun upload(base64: String, mimeType:String): String {
        val bytes = Base64.getDecoder().decode(base64)
        val ext = mimeType.substring(mimeType.indexOf('/') + 1)
        val name = UUID.randomUUID().toString() + "." + ext

        val urlStr = "https://${bucket}.s3.amazonaws.com/${name}"
        val httpMethod = "PUT"
        val contentSha256 = "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" //HOW TO GET THAT
        val request = HttpRequest(httpMethod, URI(urlStr))
        val signature = Signer.builder()
                .awsCredentials(AwsCredentials(accessKey, secretKey))
                .header("Host", "examplebucket.s3.amazonaws.com")
                .header("x-amz-date", "20130524T000000Z") //WHAT IS THIS ?
                .header("x-amz-content-sha256", contentSha256)
                .buildS3(request, contentSha256)
                .getSignature()

        val df = SimpleDateFormat("EEE', 'dd' 'MMM' 'yyyy' 'HH:mm:ss' 'Z", Locale.US)
        df.timeZone = TimeZone.getTimeZone("GMT")
        val formattedDate = df.format(Date())

        val url = URL(urlStr)
        val httpConn = url.openConnection() as HttpURLConnection
        httpConn.setDoOutput(true)
        httpConn.setRequestMethod(httpMethod)
        httpConn.setRequestProperty("Accept", "application/json")
        httpConn.setRequestProperty("Date", formattedDate)
        httpConn.setRequestProperty("Content-type", mimeType)
        httpConn.setRequestProperty("Authorization", signature)
        httpConn.getOutputStream().use { outputStream ->
            ByteArrayInputStream(bytes).use { byteArrayInputStream ->
                byteArrayInputStream.copyTo(outputStream)
            }
        }
        val res = httpConn.getResponseMessage()
        Logger.getLogger("BEASYNESS").info("UPLOAD TO S3 " + res)

        return urlStr
    }

}