DataFlex
DataFlex
Azure File Service: Upload Large File
See more Azure Cloud Storage Examples
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.Chilkat DataFlex Downloads
Use ChilkatAx-win32.pkg
Procedure Test
Boolean iSuccess
Handle hoRest
Boolean iBTls
Integer iPort
Boolean iBAutoReconnect
String sLocalFilePath
Handle hoFac
Integer iSzLocalFile
Variant vAzAuth
Handle hoAzAuth
Handle hoSbFileSize
String sResponseStr
Handle hoSbRange
Variant vSbResponseBody
Handle hoSbResponseBody
Variant vBdFileData
Handle hoBdFileData
Integer iNumBytesLeft
Integer iCurIndex
Integer iChunkSize
String sTemp1
Integer iTemp1
Boolean bTemp1
Move False To iSuccess
// 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.
Get Create (RefClass(cComChilkatRest)) To hoRest
If (Not(IsComObjectCreated(hoRest))) Begin
Send CreateComObject of hoRest
End
// Connect to the Azure Storage Blob Service
Move True To iBTls
Move 443 To iPort
Move True To iBAutoReconnect
// In this example, the storage account name is "chilkat".
Get ComConnect Of hoRest "chilkat.file.core.windows.net" iPort iBTls iBAutoReconnect To iSuccess
If (iSuccess <> True) Begin
Get ComLastErrorText Of hoRest To sTemp1
Showln sTemp1
Procedure_Return
End
// This example will upload a larger file.
Move "qa_data/zips/somethingBig.zip" To sLocalFilePath
Get Create (RefClass(cComCkFileAccess)) To hoFac
If (Not(IsComObjectCreated(hoFac))) Begin
Send CreateComObject of hoFac
End
// 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.
Get ComFileSize Of hoFac sLocalFilePath To iSzLocalFile
If (iSzLocalFile < 0) Begin
Get ComLastErrorText Of hoFac To sTemp1
Showln sTemp1
Procedure_Return
End
// Provide Azure Cloud credentials for the REST calls.
Get Create (RefClass(cComChilkatAuthAzureStorage)) To hoAzAuth
If (Not(IsComObjectCreated(hoAzAuth))) Begin
Send CreateComObject of hoAzAuth
End
Set ComAccessKey Of hoAzAuth To "AZURE_ACCESS_KEY"
// The account name used here should match the 1st part of the domain passed in the call to Connect (above).
Set ComAccount Of hoAzAuth To "chilkat"
Set ComScheme Of hoAzAuth To "SharedKey"
Set ComService Of hoAzAuth To "File"
// This causes the "x-ms-version: 2021-08-06" header to be automatically added.
Set ComXMsVersion Of hoAzAuth To "2021-08-06"
Get pvComObject of hoAzAuth to vAzAuth
Get ComSetAuthAzureStorage Of hoRest vAzAuth To iSuccess
// 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:
Get ComAddHeader Of hoRest "x-ms-type" "file" To iSuccess
// This required header specifies the final size of the file (or the maximum size it can be).
Get Create (RefClass(cComChilkatStringBuilder)) To hoSbFileSize
If (Not(IsComObjectCreated(hoSbFileSize))) Begin
Send CreateComObject of hoSbFileSize
End
Get ComAppendInt Of hoSbFileSize iSzLocalFile To iSuccess
Get ComGetAsString Of hoSbFileSize To sTemp1
Get ComAddHeader Of hoRest "x-ms-content-length" sTemp1 To iSuccess
// 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"
Get ComFullRequestNoBody Of hoRest "PUT" "/pip/somethingBig.zip" To sResponseStr
Get ComLastMethodSuccess Of hoRest To bTemp1
If (bTemp1 <> True) Begin
Get ComLastErrorText Of hoRest To sTemp1
Showln sTemp1
Procedure_Return
End
// 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.
Get ComResponseStatusCode Of hoRest To iTemp1
If (iTemp1 <> 201) Begin
// Examine the request/response to see what happened.
Get ComResponseStatusCode Of hoRest To iTemp1
Showln "response status code = " iTemp1
Get ComResponseStatusText Of hoRest To sTemp1
Showln "response status text = " sTemp1
Get ComResponseHeader Of hoRest To sTemp1
Showln "response header: " sTemp1
Showln "response body (if any): " sResponseStr
Showln "---"
Get ComLastRequestStartLine Of hoRest To sTemp1
Showln "LastRequestStartLine: " sTemp1
Get ComLastRequestHeader Of hoRest To sTemp1
Showln "LastRequestHeader: " sTemp1
Procedure_Return
End
Showln "Successfully created somethingBig.zip"
// --------------------------------------------------------------------------------
// Upload the file data...
// Make sure the headers from the "Create File" operation are removed.
Get ComClearAllHeaders Of hoRest To iSuccess
// The x-ms-write header is required for each "Put Range" request.
Get ComAddHeader Of hoRest "x-ms-write" "update" To iSuccess
Get Create (RefClass(cComChilkatStringBuilder)) To hoSbRange
If (Not(IsComObjectCreated(hoSbRange))) Begin
Send CreateComObject of hoSbRange
End
Get Create (RefClass(cComChilkatStringBuilder)) To hoSbResponseBody
If (Not(IsComObjectCreated(hoSbResponseBody))) Begin
Send CreateComObject of hoSbResponseBody
End
Get Create (RefClass(cComChilkatBinData)) To hoBdFileData
If (Not(IsComObjectCreated(hoBdFileData))) Begin
Send CreateComObject of hoBdFileData
End
// Open the file. We'll be reading and uploading in chunks..
Get ComOpenForRead Of hoFac sLocalFilePath To iSuccess
If (iSuccess <> True) Begin
Get ComLastErrorText Of hoFac To sTemp1
Showln sTemp1
Procedure_Return
End
Move iSzLocalFile To iNumBytesLeft
Move 0 To iCurIndex
While (iNumBytesLeft > 0)
Move iNumBytesLeft To iChunkSize
// Azure allows for 4MB max chunks (4 x 1024 x 1024 = 4194304)
If (iChunkSize > 4194304) Begin
Move 4194304 To iChunkSize
End
// 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
Send ComClear To hoSbRange
Get ComAppend Of hoSbRange "bytes=" To iSuccess
Get ComAppendInt Of hoSbRange iCurIndex To iSuccess
Get ComAppend Of hoSbRange "-" To iSuccess
Get ComAppendInt Of hoSbRange (iCurIndex + iChunkSize - 1) To iSuccess
// This replaces the header if it already exists..
Get ComGetAsString Of hoSbRange To sTemp1
Get ComAddHeader Of hoRest "x-ms-range" sTemp1 To iSuccess
// Read the next chunk from the local file.
Get ComClear Of hoBdFileData To iSuccess
Get pvComObject of hoBdFileData to vBdFileData
Get ComFileReadBd Of hoFac iChunkSize vBdFileData To iSuccess
Get pvComObject of hoBdFileData to vBdFileData
Get pvComObject of hoSbResponseBody to vSbResponseBody
Get ComFullRequestBd Of hoRest "PUT" "/pip/somethingBig.zip?comp=range" vBdFileData vSbResponseBody To iSuccess
If (iSuccess <> True) Begin
// This would indicate a failure where no response was received.
Get ComLastErrorText Of hoRest To sTemp1
Showln sTemp1
Procedure_Return
End
// A 201 response indicates the chunk was uploaded.
Get ComResponseStatusCode Of hoRest To iTemp1
If (iTemp1 <> 201) Begin
// Examine the request/response to see what happened.
Get ComResponseStatusCode Of hoRest To iTemp1
Showln "response status code = " iTemp1
Get ComResponseStatusText Of hoRest To sTemp1
Showln "response status text = " sTemp1
Get ComResponseHeader Of hoRest To sTemp1
Showln "response header: " sTemp1
Showln "response body (if any): " sResponseStr
Showln "---"
Get ComLastRequestStartLine Of hoRest To sTemp1
Showln "LastRequestStartLine: " sTemp1
Get ComLastRequestHeader Of hoRest To sTemp1
Showln "LastRequestHeader: " sTemp1
Procedure_Return
End
Showln "Uploaded chunk from " iCurIndex " to " (iCurIndex + iChunkSize - 1)
Move (iCurIndex + iChunkSize) To iCurIndex
Move (iNumBytesLeft - iChunkSize) To iNumBytesLeft
Loop
Send ComFileClose To hoFac
Showln "success."
End_Procedure