Amazon.S3.Model.PostObjectRequest.WriteFormData C# (CSharp) Method

        internal void WriteFormData(string boundary, Stream outputStream)
        {
            if (!String.IsNullOrEmpty(this.Key))
                WriteFormDatum(outputStream, S3Constants.PostFormDataObjectKey, this.Key, boundary);

            WriteFormDatum(outputStream, S3Constants.PostFormDataAcl, this.CannedACL, boundary);

            if (this._isSetStorageClass)
                WriteFormDatum(outputStream, HeaderKeys.XAmzStorageClassHeader, this.StorageClass, boundary);

            if (this._isSetActionStatus)
                WriteFormDatum(outputStream, S3Constants.PostFormDataStatus, ((Int32)this.SuccessActionStatus).ToString(CultureInfo.InvariantCulture), boundary);

            if (!String.IsNullOrEmpty(this.SuccessActionRedirect))
                WriteFormDatum(outputStream, S3Constants.PostFormDataRedirect, this.SuccessActionRedirect, boundary);

            if (this.SignedPolicy != null && !string.IsNullOrEmpty(this.SignedPolicy.SecurityToken))
            {
                this.Metadata[S3Constants.PostFormDataSecurityToken] = this.SignedPolicy.SecurityToken;
            }

            foreach (var key in this.Headers.Keys)
            {
                if (!String.IsNullOrEmpty(this.Headers[key]))
                    WriteFormDatum(outputStream, key, this.Headers[key], boundary);
            }

            foreach (var kvp in this.Metadata)
            {
                var metakey = kvp.Key.StartsWith(S3Constants.PostFormDataXAmzPrefix, StringComparison.Ordinal) ? kvp.Key : S3Constants.PostFormDataMetaPrefix + kvp.Key;
                WriteFormDatum(outputStream, metakey, kvp.Value, boundary);
            }

            if (this.SignedPolicy != null)
            {
                if (this.SignedPolicy.SignatureVersion == "2")
                {
                    WriteFormDatum(outputStream, S3Constants.PostFormDataPolicy, this.SignedPolicy.Policy, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataSignature, this.SignedPolicy.Signature, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataAccessKeyId, this.SignedPolicy.AccessKeyId, boundary);
                }
                else
                {
                    WriteFormDatum(outputStream, S3Constants.PostFormDataPolicy, this.SignedPolicy.Policy, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataXAmzSignature, this.SignedPolicy.Signature, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataXAmzAlgorithm, this.SignedPolicy.Algorithm, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataXAmzCredential, this.SignedPolicy.Credential, boundary);
                    WriteFormDatum(outputStream, S3Constants.PostFormDataXAmzDate, this.SignedPolicy.Date, boundary);
                }
            }
        }

        private void PostObject(PostObjectRequest request, AsyncOptions options, Action<AmazonWebServiceRequest, AmazonWebServiceResponse, Exception, AsyncOptions> callbackHelper)
        {
            string url;
            string subdomain = request.Region.Equals(RegionEndpoint.USEast1) ? "s3" : "s3-" + request.Region.SystemName;
            IDictionary<string, string> headers = new Dictionary<string, string>();

            if (request.Bucket.IndexOf('.') > -1)
                url = string.Format(CultureInfo.InvariantCulture, "https://{0}.amazonaws.com/{1}/", subdomain, request.Bucket);
            else
                url = string.Format(CultureInfo.InvariantCulture, "https://{0}.{1}.amazonaws.com", request.Bucket, subdomain);
            Uri uri = new Uri(url);

            UnityWebRequest webRequest = new UnityWebRequest(uri);

            var boundary = Convert.ToBase64String(Guid.NewGuid().ToByteArray()).Replace('=', 'z');

            headers[HeaderKeys.ContentTypeHeader] = string.Format(CultureInfo.InvariantCulture, "multipart/form-data; boundary={0}", boundary);
            headers[HeaderKeys.UserAgentHeader] = AWSSDKUtils.UserAgentHeader;

            webRequest.Method = "POST";

            using (var reqStream = new MemoryStream())
            {
                request.WriteFormData(boundary, reqStream);

                byte[] boundaryBytes = Encoding.UTF8.GetBytes(string.Format(CultureInfo.InvariantCulture, "--{0}\r\nContent-Disposition: form-data; name=\"file\"\r\n\r\n", boundary));

                reqStream.Write(boundaryBytes, 0, boundaryBytes.Length);

                using (var inputStream = null == request.Path ? request.InputStream : File.OpenRead(request.Path))
                {
                    byte[] buf = new byte[1024];
                    int bytesRead;
                    while ((bytesRead = inputStream.Read(buf, 0, 1024)) > 0)
                    {
                        reqStream.Write(buf, 0, bytesRead);
                    }
                }

                byte[] endBoundaryBytes = Encoding.UTF8.GetBytes(string.Format(CultureInfo.InvariantCulture, "\r\n--{0}--", boundary));

                reqStream.Write(endBoundaryBytes, 0, endBoundaryBytes.Length);

                webRequest.WriteToRequestBody(null, reqStream.ToArray(), headers);
            }

            var executionContext = new AsyncExecutionContext(
                new AsyncRequestContext(this.Config.LogMetrics)
                {
                    ClientConfig = this.Config,
                    OriginalRequest = request,
                    Action = callbackHelper,
                    AsyncOptions = options,
                    IsAsync = true
                },
                new AsyncResponseContext()
            );

            webRequest.SetRequestHeaders(headers);
            executionContext.RuntimeState = webRequest;


            executionContext.ResponseContext.AsyncResult =
                       new RuntimeAsyncResult(executionContext.RequestContext.Callback,
                           executionContext.RequestContext.State);
            executionContext.ResponseContext.AsyncResult.AsyncOptions = executionContext.RequestContext.AsyncOptions;
            executionContext.ResponseContext.AsyncResult.Action = executionContext.RequestContext.Action;
            executionContext.ResponseContext.AsyncResult.Request = executionContext.RequestContext.OriginalRequest;

            webRequest.BeginGetResponse(new AsyncCallback(ProcessPostResponse), executionContext);
        }