How to Access SFTP Server in Python

SFTP is a secure file transfer protocol used for transferring files over the internet. It helps you to file access, transfer and file management over any reliable data stream.

Python provides a module called PySftp used to connect to the SFTP server. It is a simple interface to SFTP and uses SSH protocol version 2 implementations.

This post will explain how to use PySftp to connect the SFTP server and manage it using Python.

Install PySftp

First, you will need to install Python and other packages to your system. You can install them with the following command:

apt-get install python3 python3-pip -y

Next, install the PySftp using the following command:

pip install pysftp

Access SFTP Server Using PySftp

In this section, we will create a Python script that connects to the remote SFTP server and list files from the specified directory:

Let's create a Python script named sftp.py:

nano sftp.py

Add the following content:

import pysftp

Hostname = "remote-ip-address"
Username = "root"
Password = "password"

with pysftp.Connection(host=Hostname, username=Username, password=Password) as sftp:
print("Connection successfully established ... ")
# Switch to a remote directory
sftp.cwd('/opt/')

# Obtain structure of the remote directory '/opt'
directory_structure = sftp.listdir_attr()

# Print data
for attr in directory_structure:
print(attr.filename, attr)

Save and close the file when you are finished.

In the above script, we have imported the PySftp module then store remote SFTP username, password, and IP address in the variable. Then, we have used Python statements to establish a secure SFTP connection using IP, username, and password stored in the variable. After the successful connection, we will switch the remote directory to /opt and list all files one by one.

You can now run the sftp.py script using the following command:

python3 sftp.py

You should see the following output:

Connection successfully established ...
fstab -rw-r--r-- 1 0 0 558 22 Jul 05:24 fstab
host.conf -rw-r--r-- 1 0 0 92 22 Jul 05:24 host.conf
hostname -rw-r--r-- 1 0 0 11 22 Jul 05:24 hostname
hosts -rw-r--r-- 1 0 0 196 22 Jul 05:24 hosts
hosts.allow -rw-r--r-- 1 0 0 411 22 Jul 05:24 hosts.allow
hosts.deny -rw-r--r-- 1 0 0 711 22 Jul 05:24 hosts.deny
netplan drwxr-xr-x 1 0 0 4096 22 Jul 05:25 netplan
networkd-dispatcher drwxr-xr-x 1 0 0 4096 22 Jul 05:25 networkd-dispatcher
networks -rw-r--r-- 1 0 0 80 22 Jul 05:25 networks

Upload a File to SFTP Using PySftp

If you want to upload a file from your local system to the SFTP server using PySftp, you just need to use the sftp.put() method of the SFTP client.

Let's create a sftp.py script to upload a file named initrd.img located at /boot/initrd.img on the local system to the remote SFTP server in the /mnt directory.

nano sftp.py

Add the following content:

import pysftp

Hostname = "remote-ip-address"
Username = "root"
Password = "password"

with pysftp.Connection(host=Hostname, username=Username, password=Password) as sftp:
print("Connection successfully established ... ")

# Define a file that you want to upload from your local directory
localFilePath = '/boot/initrd.img'

# Define the remote path where the file will be uploaded
remoteFilePath = '/mnt/initrd.img'

# Use put method to upload a file
sftp.put(localFilePath, remoteFilePath)

# Switch to a remote directory
sftp.cwd('/mnt/')

# Obtain structure of the remote directory '/opt'
directory_structure = sftp.listdir_attr()

# Print data
for attr in directory_structure:
print(attr.filename, attr)

Save and close the file when you are finished.

Where:

• localFilePath is the path of the local file.
• remoteFilePath is the path of the remote file.
• sftp.put is the method used to upload a file to the SFTP server.

Next, run the sftp.py script using the following command:

python3 sftp.py

You should get the following output:

Connection successfully established ...
initrd.img -rw-r--r-- 1 0 0 19543043 22 Jul 05:40 initrd.img

Download a File From SFTP Using PySftp

In this section, we will use the sftp.get() method to download a file from the remote SFTP server.

Let's create a sftp.py script using the following command:

nano sftp.py

Add the following content:

import pysftp

Hostname = "remote-ip-address"
Username = "root"
Password = "password"

with pysftp.Connection(host=Hostname, username=Username, password=Password) as sftp:
print("Connection successfully established ... ")

# Define the remote path where the file will be uploaded
remoteFilePath = '/etc/hosts'

# Define a file that you want to upload from your local directorty
localFilePath = '/opt/hosts'

# Use get method to download a file
sftp.get(remoteFilePath, localFilePath)

Save and close the file when you are finished.

Next, run the sftp.py script to download /etc/hosts file from the remote SFTP server to the local system:

python3 sftp.py

You should get the following output:

Connection successfully established ...

Delete a File From SFTP Using PySftp

You can also remove a file on the SFTP server using the sftp.remove() method.

In the following example, we will remove a file named /opt/file1.txt on the SFTP server.

Let's create a sftp.py script as shown below:

nano sftp.py

Add the following content:

import pysftp

Hostname = "remote-ip-address"
Username = "root"
Password = "password"

with pysftp.Connection(host=Hostname, username=Username, password=Password) as sftp:
print("Connection successfully established ... ")

# Define the remote path file path
removeFilePath = '/opt/file1.txt'

sftp.remove(removeFilePath)

Save and close the file, then run it with the following command:

python3 sftp.py

You should get the following output:

Connection successfully established ...

Conclusion

In the above guide, we explained how to use the PySftp Python module to manage and working with SFTP in Python. The PySftp module has a wide range of methods that you can use to do multiple things, like handling permissions, etc.

SFTP server FAQs