Automating Configuration Backup

In this example, we will use PyGithub to back up a directory containing our router configurations. We have seen how we can retrieve the information from our devices with Python or Ansible; we can now check them into GitHub.

We have a subdirectory, named config, with our router configs in text format:

$ ls configs/ 
iosv-1 iosv-2
$ cat configs/iosv-1 
Building configuration...
Current configuration : 4573 bytes
!
! Last configuration change at 02:50:05 UTC Sat Jun 2 2018 by cisco
!
version 15.6
service timestamps debug datetime msec
...

We can use the following script, Chapter14_1.py, to retrieve the latest index from our GitHub repository, build the content that we need to commit, and automatically commit the configuration:

#!/usr/bin/env python3
# reference: https://stackoverflow.com/questions/38594717/how-do-i-push-new-files-to-github
from github import Github, InputGitTreeElement
import os
github_token = '<token>'
configs_dir = 'configs'
github_repo = 'TestRepo'
# Retrieve the list of files in configs directory
file_list = []
for dirpath, dirname, filenames in os.walk(configs_dir):
    for f in filenames:
        file_list.append(configs_dir + "/" + f)
g = Github(github_token)
repo = g.get_user().get_repo(github_repo)
commit_message = 'add configs'
master_ref = repo.get_git_ref('heads/master')
master_sha = master_ref.object.sha
base_tree = repo.get_git_tree(master_sha)
element_list = list()
for entry in file_list: 
    with open(entry, 'r') as input_file:
        data = input_file.read()
    element = InputGitTreeElement(entry, '100644', 'blob', data)
    element_list.append(element)
# Create tree and commit
tree = repo.create_git_tree(element_list, base_tree)
parent = repo.get_git_commit(master_sha)
commit = repo.create_git_commit(commit_message, tree, [parent])
master_ref.edit(commit.sha)

We can see the configs directory in the GitHub repository:

Figure 14.12: Configs directory

The commit history shows the commit from our script:

Figure 14.13: Commit history

In the GitHub example section, we saw how we could collaborate with other developers by forking the repository and making pull requests. Let’s look at how we can further collaborate with Git.