Chilkat2-Python
Chilkat2-Python
S3 Upload the Parts for a Multipart Upload
See more Amazon S3 (new) Examples
This example uploads a large file in parts. The multipart upload needs to have been first initiated prior to uploading the parts.See http://docs.aws.amazon.com/AmazonS3/latest/API/mpUploadUploadPart.html for more information about uploading parts.
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import sys
import chilkat2
success = False
# In the 1st step for uploading a large file, the multipart upload was initiated
# as shown here: Initiate Multipart Upload
# Other S3 Multipart Upload Examples:
# Complete Multipart Upload
# Abort Multipart Upload
# List Parts
# When we initiated the multipart upload, we saved the XML response to a file. This
# XML response contains the UploadId. We'll begin by loading that XML and getting
# the Upload ID.
xmlInit = chilkat2.Xml()
success = xmlInit.LoadXmlFile("s3_multipart_uploads/initiate.xml")
if (success != True):
print("Did not find the initiate.xml XML file.")
sys.exit()
uploadId = xmlInit.GetChildContent("UploadId")
print("UploadId = " + uploadId)
# When uploading parts, we need to keep an XML record of each part number
# and its corresponding ETag, which is received in the response for each part.
# There can be up to 10000 parts, numbered 1 to 10000.
# After all parts have been uploaded, the final step will be to complete
# the multipart upload (see Complete Multipart Upload)
# In this example, the large file we want to upload is somethingBig.zip
fileToUploadPath = "s3_multipart_uploads/somethingBig.zip"
# The minimum allowed part size is 5MB (5242880 bytes). The last part can be smaller because
# it will contain the remainder of the file. (This minimum is enforced by the AWS service.)
# We'll use the minimum allowed part size for this example.
partSize = 5242880
# Let's use Chilkat's FileAccess API to examine the file to be uploaded. We'll get the size
# of the file and find out how many parts will be needed, including the final "partial" part.
fac = chilkat2.FileAccess()
fac.OpenForRead(fileToUploadPath)
# How many parts will there be if each part is 5242880 bytes?
numParts = fac.GetNumBlocks(partSize)
print("numParts = " + str(numParts))
fac.FileClose()
# Imagine that we may be running this for the 1st time, or maybe we already
# attempted to upload parts, and something failed. Maybe there was a network problem
# the resulted in not all parts getting uploaded. We'll write this code so that if run again,
# it will upload whatever parts haven't yet been uploaded.
# We'll keep a partsList.xml file to record the parts that have already been successfully
# uploaded. If this file does not yet exist, we'll create it..
partsListFile = "s3_multipart_uploads/partsList.xml"
partsListXml = chilkat2.Xml()
if (fac.FileExists(partsListFile) == True):
partsListXml.LoadXmlFile(partsListFile)
# Make sure the top-level tag is "CompleteMultipartUpload"
partsListXml.Tag = "CompleteMultipartUpload"
# --------------------------------------
# Before entering the loop to upload parts,
# setup the REST object with AWS authentication,
# and make the initial connection.
rest = chilkat2.Rest()
# Connect to the Amazon AWS REST server.
bTls = True
port = 443
bAutoReconnect = True
success = rest.Connect("s3.amazonaws.com",port,bTls,bAutoReconnect)
# ----------------------------------------------------------------------------
# Important: For buckets created in regions outside us-east-1,
# there are three important changes that need to be made.
# See Working with S3 Buckets in Non-us-east-1 Regions for the details.
# ----------------------------------------------------------------------------
# Provide AWS credentials for the REST call.
authAws = chilkat2.AuthAws()
authAws.AccessKey = "AWS_ACCESS_KEY"
authAws.SecretKey = "AWS_SECRET_KEY"
authAws.ServiceName = "s3"
success = rest.SetAuthAws(authAws)
# Set the bucket name via the HOST header.
# In this case, the bucket name is "chilkat100".
rest.Host = "chilkat100.s3.amazonaws.com"
# --------------------------------------
partNumber = 1
sbPartNumber = chilkat2.StringBuilder()
while (partNumber <= numParts) :
print("---- " + str(partNumber) + " ----")
# This cumbersome way of converting an integer to a string is because
# Chilkat examples are written in a script that is converted to many programming languages.
# At this time, the translator does not have integer-to-string code generation capability..
sbPartNumber.Clear()
sbPartNumber.AppendInt(partNumber)
bPartAlreadyUploaded = False
# If there are no children, then the XML is empty and no parts have yet been uploaded.
numUploadedParts = partsListXml.NumChildren
if (numUploadedParts > 0):
# If some parts have been uploaded, check to see if this particular part was already upload.
# If so, then it can be skipped.
# Position ourselves at the 1st record.
# xRec0 is a CkXml
xRec0 = partsListXml.GetChild(0)
# foundRec is a CkXml
foundRec = xRec0.FindNextRecord("PartNumber",sbPartNumber.GetAsString())
if (xRec0.LastMethodSuccess == True):
bPartAlreadyUploaded = True
print("Part " + str(partNumber) + " was previously uploaded.")
print(foundRec.GetXml())
# If this part was not already uploaded, we need to upload.
# Also update the partsListXml and save as each part is successfully uploaded.
if (bPartAlreadyUploaded == False):
print("Uploading part " + str(partNumber) + " ...")
# Setup the stream source for the large file to be uploaded..
fileStream = chilkat2.Stream()
fileStream.SourceFile = fileToUploadPath
# The Chilkat Stream API has features to make uploading a parts
# of a file easy. Indicate the part size by setting the SourceFilePartSize
# property.
fileStream.SourceFilePartSize = partSize
# Our HTTP start line to upload a part will look like this:
# PUT /ObjectName?partNumber=PartNumber&uploadId=UploadId HTTP/1.1
# Set the query params. We'll need partNumber and uploadId.
# Make sure the query params from previous iterations are clear.
rest.ClearAllQueryParams()
rest.AddQueryParam("partNumber",sbPartNumber.GetAsString())
rest.AddQueryParam("uploadId",uploadId)
# Upload this particular file part.
# Tell the fileStream which part is being uploaded.
# Our partNumber is 1-based (the 1st part is at index 1), but the fileStream's SourceFilePart
# property is 0-based. Therefore we use partNumber-1.
fileStream.SourceFilePart = partNumber - 1
# Because the SourceFilePart and SourceFilePartSize properties are set, the stream will
# will provide just that part of the file.
responseStr = rest.FullRequestStream("PUT","/somethingBig.zip",fileStream)
if (rest.LastMethodSuccess != True):
print(rest.LastErrorText)
sys.exit()
if (rest.ResponseStatusCode != 200):
# Examine the request/response to see what happened.
print("response status code = " + str(rest.ResponseStatusCode))
print("response status text = " + rest.ResponseStatusText)
print("response header: " + rest.ResponseHeader)
print("response body: " + responseStr)
print("---")
print("LastRequestStartLine: " + rest.LastRequestStartLine)
print("LastRequestHeader: " + rest.LastRequestHeader)
sys.exit()
# OK, this part was uploaded..
# The response will have a 0-length body. The only information we need is the
# ETag response header field.
etag = rest.ResponseHdrByName("ETag")
# It should be present, but just in case there was no ETag header...
if (rest.LastMethodSuccess != True):
print("No ETag response header found!")
print("response header: " + rest.ResponseHeader)
sys.exit()
# We need to add record to the partsListXml.
# The record will look like this:
# <Part>
# <PartNumber>PartNumber</PartNumber>
# <ETag>ETag</ETag>
# </Part>
# xPart is a CkXml
xPart = partsListXml.NewChild("Part","")
xPart.NewChildInt2("PartNumber",partNumber)
xPart.NewChild2("ETag",etag)
success = partsListXml.SaveXml(partsListFile)
if (success != True):
print(partsListXml.LastErrorText)
sys.exit()
print("-- Part " + str(partNumber) + " uploaded. ---------------------")
partNumber = partNumber + 1
print("Finished. All parts uploaded.")