|
|
(JavaScript) Azure File Service: Upload Large File
Sample code to upload a large file to a directory in a share in the Azure File Service. A file is uploaded by first creating the file in the Azure share and then writing ranges of bytes to the file. Azure imposes a 4MB limit for each PUT to write a range. Files larger than 4MB need to be uploaded by making multiple "Put Range" calls. This example uploads a large file requiring multiple "Put Range" calls.
var success = false;
// Azure File Service Example: Upload a large file.
// See: https://docs.microsoft.com/en-us/rest/api/storageservices/create-share
// also see: https://docs.microsoft.com/en-us/rest/api/storageservices/put-range
// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.
var rest = new CkRest();
// Connect to the Azure Storage Blob Service
var bTls = true;
var port = 443;
var bAutoReconnect = true;
// In this example, the storage account name is "chilkat".
success = rest.Connect("chilkat.file.core.windows.net",port,bTls,bAutoReconnect);
if (success !== true) {
console.log(rest.LastErrorText);
return;
}
// This example will upload a larger file.
var localFilePath = "qa_data/zips/somethingBig.zip";
var fac = new CkFileAccess();
// Note: The FileSize method returns a signed 32-bit integer. If the file is potentially larger than 2GB, call FileSizeStr instead to return
// the size of the file as a string, then convert to an integer value.
var szLocalFile = fac.FileSize(localFilePath);
if (szLocalFile < 0) {
console.log(fac.LastErrorText);
return;
}
// Provide Azure Cloud credentials for the REST calls.
var azAuth = new CkAuthAzureStorage();
azAuth.AccessKey = "AZURE_ACCESS_KEY";
// The account name used here should match the 1st part of the domain passed in the call to Connect (above).
azAuth.Account = "chilkat";
azAuth.Scheme = "SharedKey";
azAuth.Service = "File";
// This causes the "x-ms-version: 2021-08-06" header to be automatically added.
azAuth.XMsVersion = "2021-08-06";
success = rest.SetAuthAzureStorage(azAuth);
// Note: The application does not need to explicitly set the following
// headers: x-ms-date, Authorization. These headers
// are automatically set by Chilkat.
// However, a few additional headers are required for the "Create File" operation:
rest.AddHeader("x-ms-type","file");
// This required header specifies the final size of the file (or the maximum size it can be).
var sbFileSize = new CkStringBuilder();
sbFileSize.AppendInt(szLocalFile);
rest.AddHeader("x-ms-content-length",sbFileSize.GetAsString());
// Send a PUT request to create the file (or replace the file if it already exists).
// This will initialize the file in the Azure file storage. To upload content, we'll need
// to do the "Put Range" operation one or more times.
// The following will create the file "somethingBig.zip" in the share "pip"
var responseStr = rest.FullRequestNoBody("PUT","/pip/somethingBig.zip");
if (rest.LastMethodSuccess !== true) {
console.log(rest.LastErrorText);
return;
}
// When successful, the Azure File Service will respond with a 201 (Created) response status code,
// with no XML response body. If an error response is returned, there will be an XML response body.
if (rest.ResponseStatusCode !== 201) {
// Examine the request/response to see what happened.
console.log("response status code = " + rest.ResponseStatusCode);
console.log("response status text = " + rest.ResponseStatusText);
console.log("response header: " + rest.ResponseHeader);
console.log("response body (if any): " + responseStr);
console.log("---");
console.log("LastRequestStartLine: " + rest.LastRequestStartLine);
console.log("LastRequestHeader: " + rest.LastRequestHeader);
return;
}
console.log("Successfully created somethingBig.zip");
// --------------------------------------------------------------------------------
// Upload the file data...
// Make sure the headers from the "Create File" operation are removed.
rest.ClearAllHeaders();
// The x-ms-write header is required for each "Put Range" request.
rest.AddHeader("x-ms-write","update");
var sbRange = new CkStringBuilder();
var sbResponseBody = new CkStringBuilder();
var bdFileData = new CkBinData();
// Open the file. We'll be reading and uploading in chunks..
success = fac.OpenForRead(localFilePath);
if (success !== true) {
console.log(fac.LastErrorText);
return;
}
var numBytesLeft = szLocalFile;
var curIndex = 0;
while (numBytesLeft > 0) {
var chunkSize = numBytesLeft;
// Azure allows for 4MB max chunks (4 x 1024 x 1024 = 4194304)
if (chunkSize > 4194304) {
chunkSize = 4194304;
}
// The only tricky part here is to correctly add the x-ms-range header.
// It will be formatted like this:
// x-ms-range: bytes=0-759623
sbRange.Clear();
sbRange.Append("bytes=");
sbRange.AppendInt(curIndex);
sbRange.Append("-");
sbRange.AppendInt(curIndex+chunkSize - 1);
// This replaces the header if it already exists..
rest.AddHeader("x-ms-range",sbRange.GetAsString());
// Read the next chunk from the local file.
bdFileData.Clear();
success = fac.FileReadBd(chunkSize,bdFileData);
success = rest.FullRequestBd("PUT","/pip/somethingBig.zip?comp=range",bdFileData,sbResponseBody);
if (success !== true) {
// This would indicate a failure where no response was received.
console.log(rest.LastErrorText);
return;
}
// A 201 response indicates the chunk was uploaded.
if (rest.ResponseStatusCode !== 201) {
// Examine the request/response to see what happened.
console.log("response status code = " + rest.ResponseStatusCode);
console.log("response status text = " + rest.ResponseStatusText);
console.log("response header: " + rest.ResponseHeader);
console.log("response body (if any): " + responseStr);
console.log("---");
console.log("LastRequestStartLine: " + rest.LastRequestStartLine);
console.log("LastRequestHeader: " + rest.LastRequestHeader);
return;
}
console.log("Uploaded chunk from " + curIndex + " to " + (curIndex+chunkSize - 1));
curIndex = curIndex+chunkSize;
numBytesLeft = numBytesLeft - chunkSize;
}
fac.FileClose();
console.log("success.");
|
