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API upload corrupted

API upload corrupted

agarrkoch
Explorer | Level 4

Hi,

 

I'm a novice coder. Can someone take a look at the following method and tell me if I'm doing something wrong? Sometimes the files I upload to dropbox are corrupts. I'm working with large audiovisual files. This doesn't always happen. Only occasionally.

 

# Uploads file to dropbox
def upload_file_to_dropbox(self, file_path, dropbox_path, max_retries=5):
for attempt in range(max_retries):
try:
#Step 0: Check if ACCESS_TOKEN is still valid
if self.token_expired():
self.refresh_access_token()

# Step 1: Initiate an upload session
session_start_url = 'https://content.dropboxapi.com/2/files/upload_session/start'
headers = {
'Authorization': 'Bearer ' + self.ACCESS_TOKEN,
'Content-Type': 'application/octet-stream'
}
response = requests.post(session_start_url, headers=headers)
if response.status_code != 200:
print("Failed to initiate upload session:", response.text)
return

session_id = response.json()['session_id']
offset = 0

# Step 2: Upload the file in chunks
chunk_size = 4 * 1024 * 1024 # 4MB chunk size
with open(file_path, 'rb') as file:
while True:
if self.token_expired():
self.refresh_access_token()

chunk = file.read(chunk_size)
if not chunk:
break
upload_url = 'https://content.dropboxapi.com/2/files/upload_session/append_v2'
headers = {
'Authorization': 'Bearer ' + self.ACCESS_TOKEN,
'Content-Type': 'application/octet-stream',
'Dropbox-API-Arg': '{"cursor": {"session_id": "' + session_id + '", "offset": ' + str(offset) + '}}'
}
response = requests.post(upload_url, headers=headers, data=chunk)

if response.status_code == 429:
seconds = response.json()["error"]["retry_after"]
for i in range(seconds, 0, -1):
sys.stdout.write("\rToo many requests. Retrying chunk upload in {:2d} seconds.".format(i))
sys.stdout.flush()
time.sleep(1)
continue
# eventually edit this statement for exponential back off
# for some reason dropbox outputs this response as HTML, instead of JSON
elif 'Error: 503' in response.text:
seconds = 10
for i in range(seconds, 0, -1):
sys.stdout.write("\rDropbox service availability issue. Retrying chunk upload in {:2d} seconds.".format(i))
sys.stdout.flush()
time.sleep(1)
continue
elif response.status_code != 200:
print("Failed to upload chunk:", response.text)
return

offset += len(chunk)
self.bytes_read += len(chunk)
progress = min(self.bytes_read / self.total_size, 1.0) * 100
sys.stdout.write(f"\rUpload progress: {progress:.2f}% ({self.bytes_read}/{self.total_size} bytes)")
sys.stdout.flush()

# Step 3: Complete the upload session
session_finish_url = 'https://content.dropboxapi.com/2/files/upload_session/finish'
headers = {
'Authorization': 'Bearer ' + self.ACCESS_TOKEN,
'Content-Type': 'application/octet-stream',
'Dropbox-API-Arg': '{"cursor": {"session_id": "' + session_id + '", "offset": ' + str(offset) + '}, "commit": {"path": "' + dropbox_path + '", "mode": "add", "autorename": true, "mute": false}}'
}
response = requests.post(session_finish_url, headers=headers, timeout=30)
if response.status_code != 200:
print("Failed to complete upload session:", response.text)
return
return # Exit the function after successful upload

except ConnectionError as e:
if attempt < max_retries - 1:
print(f"ConnectionError: Retry attempt {attempt + 1}")
else:
raise e
1 Reply 1

DB-Des
Dropbox Engineer

Hi @agarrkoch,

 

Since the file corruption you are reporting is happening intermittently, we would recommend adding a validation step in your app to confirm that the local copy of a file has the same contents as the copy of the file on Dropbox. This can be achieved by using the "content hash".

You can retrieve the content hash for any file(s) via a number of different endpoints on the Dropbox API, such as /2/files/get_metadata or /2/files/list_folder[/continue].

 

Feel free to reference the following guide for more details on how to calculate the content hash: https://www.dropbox.com/developers/reference/content-hash

 

I hope you find this information helpful!

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