Working with the filesystem in Python

You can work with files within a workflow. For instance, downloading content from some service to upload to another. Here are some sample code for common file operations.

The /tmp directory

Within a workflow, you have full read-write access to the /tmp directory. You have 2GB of available space in /tmp to save any file.

Managing /tmp across workflow runs

The /tmp directory is stored on the virtual machine that runs your workflow. We call this the execution environment (“EE”). More than one EE may be created to handle high-volume workflows. And EEs can be destroyed at any time (for example, after about 10 minutes of receiving no events). This means that you should not expect to have access to files across executions. At the same time, files may remain, so you should clean them up to make sure that doesn’t affect your workflow. Use the tempfile module to cleanup files after use, or delete the files manually.

Writing a file to /tmp

import requests
 
def handler(pd: "pipedream"):
  # Download the Python logo
  r = requests.get("https://www.python.org/static/img/python-logo@2x.png")
 
  # Create a new file python-logo.png in the /tmp/data directory
  with open("/tmp/python-logo.png", "wb") as f:
    # Save the content of the HTTP response into the file
    f.write(r.content)

Now /tmp/python-logo.png holds the official Python logo.

Reading a file from /tmp

You can also open files you have previously stored in the /tmp directory. Let’s open the python-logo.png file.

import os
 
def handler(pd: "pipedream"):
  with open("/tmp/python-logo.png") as f:
    # Store the contents of the file into a variable
    file_data = f.read()

Listing files in /tmp

If you need to check what files are currently in /tmp you can list them and print the results to the Logs section of Results:

import os
 
def handler(pd: "pipedream"):
  # Prints the files in the tmp directory
  print(os.listdir("/tmp"))

Deleting a file

import os
 
def handler(pd: "pipedream"):
  print(os.unlink("/tmp/your-file"))

Downloading a file to /tmp

See this example to learn how to download a file to /tmp.

Uploading a file from /tmp

See this example to learn how to upload a file from /tmp in an HTTP request.

Downloading a file, uploading it in another multipart/form-data request

import requests
from requests_toolbelt.multipart.encoder import MultipartEncoder
import os
 
def handler(pd: "pipedream"):
  download_url = "https://example.com"
  upload_url = "http://httpbin.org/post"
  file_path = "/tmp/index.html"
  content_type = "text/html"
 
  # DOWNLOAD
  with requests.get(download_url, stream=True) as response:
      response.raise_for_status()
      with open(file_path, "wb") as file:
          for chunk in response.iter_content(chunk_size=8192):
              file.write(chunk)
 
  # UPLOAD
  multipart_data = MultipartEncoder(fields={
    'file': (os.path.basename(file_path), open(file_path, 'rb'), content_type)
  })
  response = requests.post(
    upload_url,
    data=multipart_data,
    headers={'Content-Type': multipart_data.content_type}
  )

/tmp limitations

The /tmp directory can store up to 2GB of storage. Also the storage may be wiped or may not exist between workflow executions.

To avoid errors, assume that the /tmp directory is empty between workflow runs. Please refer to the disk limits for details.