Terraform plan automation

Support/tf_plan_automation/README.md

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+# Terraform plan automation
+To execute terraform plan across multiple folders (terraform modules) which have git changes, e.g. when you have made changes to multiple modules and you want to run terraform plan in one go we can use this utility.
+
+
+### To execute
+
+Execute the following command
+```shell
+python tfPlanAutomate.py --root_dir /Code/terraform-multicloud-resources \
+        --sub_dir aws/prod-applications/eu-west-1/apps
+```
+This will execute terraform plan on all subdirectories under sub_dir parameter which have 
+git changes.

Support/tf_plan_automation/tfPlanAutomate.py

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+"""Executes terraform plan on folders where github changes are detected under a subfolder
+"""
+
+import argparse
+import os
+import subprocess
+
+
+def get_directories_changed(parent_directory: str):
+    """Builds a list of directories under a sub folder in a repository
+       where a change is detected through git diff
+
+    Args:
+        parent_directory (str): Parent directory to search for changes
+
+    Returns:
+        list: Directories updated through latest changes.
+    """
+    os.chdir(parent_directory)
+    result = subprocess.run(
+        ["git", "diff", "--name-only", "--exit-code"], stdout=subprocess.PIPE
+    )
+    directories_changed = []
+    for filepath in result.stdout.decode().splitlines():
+        filepath = parent_directory + os.sep + str(filepath)
+        dir_path = filepath.rsplit(os.sep, 1)[0]
+        directories_changed.append(dir_path)
+    return directories_changed
+
+
+def find_tf_directories(path: str):
+    """Function to find .tf file folders in subfolders
+
+    Args:
+        path (str): Path under git repo location where to search for terraform file
+           containing folders
+
+    Returns:
+        list: Folder path where the terrform files exist under the search path
+    """
+    tf_folders = []
+    for root, dirs, files in os.walk(path):
+        for file in files:
+            if file.endswith(".tf"):
+                tf_folders.append(root)
+                break
+    return tf_folders
+
+
+# Function to run terraform init and plan in a directory
+def run_terraform(path, issues_with_folders):
+    """Executes terraform init and terraform plan in the identified folders.
+       Builds a list of folders where issues are found during cmd execution.
+
+    Args:
+        path (str): Path under which to execute terraform init and plan
+        issues_with_folders (list): List of folder with issues built for review
+    """
+    try:
+        os.chdir(path)
+        subprocess.run(["terraform", "init"], check=True)
+        result = subprocess.run(["terraform", "plan"], capture_output=True)
+        if result.returncode != 0:
+            output = result.stdout.decode("utf-8")
+            issues_with_folders.append({path: str(output)})
+        else:
+            print(f"Terraform commands executed successfully in {path}")
+    except subprocess.CalledProcessError as e:
+        print(f"Error executing Terraform commands in {path}: {e}")
+        issues_with_folders.append({path: str(e)})
+
+
+def parse_arguments():
+    """Parses command line arguments to identify which repository to process
+
+    Returns:
+        dict: arguments received from command line
+    """
+    parser = argparse.ArgumentParser(
+        description="Run Terraform commands in directories with changes in .tf files."
+    )
+    parser.add_argument(
+        "-root",
+        "--root_dir",
+        type=str,
+        help="Root directory of the Terraform project",
+    )
+    parser.add_argument(
+        "-sub",
+        "--sub_dir",
+        type=str,
+        help="Root directory of the Terraform project",
+    )
+    return parser.parse_args()
+
+
+def _review_folders_with_issues(issues_with_folders: list):
+    """Prints issue with folders found during terraform commands execution.
+
+    Args:
+        issues_with_folders (list): [{folder: error}, ...] format
+    """
+    folders_with_issue = len(issues_with_folders)
+    for i, issue in enumerate(issues_with_folders):
+        print(f"Issues with terraform plan on folder {i+1}/{folders_with_issue}:")
+        for key in issue:
+            print(key, issue[key])
+
+
+def main():
+    """Processes the terraform init and plan process for target repository"""
+    args = parse_arguments()
+    directories_changed = get_directories_changed(args.root_dir)
+    tf_dirs = find_tf_directories(args.root_dir + os.sep + args.sub_dir)
+    issues_with_folders = []
+    for check_path in tf_dirs:
+        if check_path in directories_changed:
+            run_terraform(check_path, issues_with_folders)
+    _review_folders_with_issues(issues_with_folders)
+
+
+if __name__ == "__main__":
+    main()