fix(get-app): handle existing directory and other formatting changes

* if a directory for the application already exists, provide user with 2
  options:

  * ask to remove the directory and reclone (overwrite)
  * ask if the user wants to reinstall the application

* separate get_app_name from get_app

* move building assets and postprocessing to install_app method

* make formatting changes to the code for flake8

* use reload_module from six instead of builtins

Signed-off-by: Chinmay D. Pai <chinmaydpai@gmail.com>

bench/app.py

@@ -4,6 +4,7 @@ from .utils import (exec_cmd, get_frappe, check_git_for_shallow_clone, build_ass
 	restart_supervisor_processes, get_cmd_output, run_frappe_cmd, CommandFailedError,
 	restart_systemd_processes)
 from .config.common_site_config import get_config
+from six import reload_module
 
 import logging
 import requests
@@ -14,6 +15,7 @@ import subprocess
 import bench
 import sys
 import shutil
+import click
 
 logging.basicConfig(level="DEBUG")
 logger = logging.getLogger(__name__)
@@ -93,7 +95,7 @@ def remove_from_excluded_apps_txt(app, bench_path='.'):
 		return write_excluded_apps_txt(apps, bench_path=bench_path)
 
 def get_app(git_url, branch=None, bench_path='.', build_asset_files=True, verbose=False,
-	postprocess = True):
+		postprocess=True, overwrite=False):
 	# from bench.utils import check_url
 	try:
 		from urlparse import urljoin
@@ -114,37 +116,43 @@ def get_app(git_url, branch=None, bench_path='.', build_asset_files=True, verbos
 
 	# Gets repo name from URL
 	repo_name = git_url.rsplit('/', 1)[1].rsplit('.', 1)[0]
-	logger.info('getting app {}'.format(repo_name))
 	shallow_clone = '--depth 1' if check_git_for_shallow_clone() else ''
 	branch = '--branch {branch}'.format(branch=branch) if branch else ''
 
+	if os.path.isdir(os.path.join(bench_path, 'apps', repo_name)):
+		# application directory already exists
+		# prompt user to overwrite it
+		if overwrite or click.confirm('''A directory for the application "{0}" already exists.
+Do you want to continue and overwrite it?'''):
+			shutil.rmtree(os.path.join(bench_path, 'apps', repo_name))
+		elif click.confirm('''Do you want to reinstall the existing application?''', abort=True):
+			app_name = get_app_name(bench_path, repo_name)
+			print("Reinstalling {0}".format(app_name))
+			install_app(app=app_name, bench_path=bench_path, verbose=verbose, build_asset_files=build_asset_files)
+			sys.exit(1)
+
+	logger.info('Getting app {0}'.format(repo_name))
 	exec_cmd("git clone {git_url} {branch} {shallow_clone} --origin upstream".format(
 		git_url=git_url,
 		shallow_clone=shallow_clone,
 		branch=branch),
 		cwd=os.path.join(bench_path, 'apps'))
 
-	#Retrieves app name from setup.py
+	app_name = get_app_name(bench_path, repo_name)
+	print("Installing {0}".format(app_name))
+	install_app(app=app_name, bench_path=bench_path, verbose=verbose, build_asset_files=build_asset_files)
+
+
+def get_app_name(bench_path, repo_name):
+	# retrieves app name from setup.py
 	app_path = os.path.join(bench_path, 'apps', repo_name, 'setup.py')
 	with open(app_path, 'rb') as f:
 		app_name = re.search(r'name\s*=\s*[\'"](.*)[\'"]', f.read().decode('utf-8')).group(1)
 		if repo_name != app_name:
 			apps_path = os.path.join(os.path.abspath(bench_path), 'apps')
 			os.rename(os.path.join(apps_path, repo_name), os.path.join(apps_path, app_name))
+		return app_name
 
-	print('installing', app_name)
-	install_app(app=app_name, bench_path=bench_path, verbose=verbose)
-
-	if postprocess:
-
-		if build_asset_files:
-			build_assets(bench_path=bench_path, app=app_name)
-		conf = get_config(bench_path=bench_path)
-
-		if conf.get('restart_supervisor_on_update'):
-			restart_supervisor_processes(bench_path=bench_path)
-		if conf.get('restart_systemd_on_update'):
-			restart_systemd_processes(bench_path=bench_path)
 
 def new_app(app, bench_path='.'):
 	# For backwards compatibility
@@ -160,7 +168,8 @@ def new_app(app, bench_path='.'):
 		run_frappe_cmd('make-app', apps, app, bench_path=bench_path)
 	install_app(app, bench_path=bench_path)
 
-def install_app(app, bench_path=".", verbose=False, no_cache=False):
+
+def install_app(app, bench_path=".", verbose=False, no_cache=False, postprocess=True, build_asset_files=True):
 	logger.info("installing {}".format(app))
 
 	pip_path = os.path.join(bench_path, "env", "bin", "pip")
@@ -168,11 +177,23 @@ def install_app(app, bench_path=".", verbose=False, no_cache=False):
 	app_path = os.path.join(bench_path, "apps", app)
 	cache_flag = "--no-cache-dir" if no_cache else ""
 
-	exec_cmd("{pip} install {quiet} -U -e {app} {no_cache}".format(pip=pip_path, quiet=quiet_flag, app=app_path, no_cache=cache_flag))
+	exec_cmd("{pip} install {quiet} -U -e {app} {no_cache}".format(pip=pip_path,
+									quiet=quiet_flag, app=app_path, no_cache=cache_flag))
 	add_to_appstxt(app, bench_path=bench_path)
 
+	if postprocess:
+		if build_asset_files:
+			build_assets(bench_path=bench_path, app=app)
+		conf = get_config(bench_path=bench_path)
+
+		if conf.get('restart_supervisor_on_update'):
+			restart_supervisor_processes(bench_path=bench_path)
+		if conf.get('restart_systemd_on_update'):
+			restart_systemd_processes(bench_path=bench_path)
+
+
 def remove_app(app, bench_path='.'):
-	if not app in get_apps(bench_path):
+	if app not in get_apps(bench_path):
 		print("No app named {0}".format(app))
 		sys.exit(1)
 
@@ -281,8 +302,7 @@ def get_current_branch(app, bench_path='.'):
 
 def get_remote(app, bench_path='.'):
 	repo_dir = get_repo_dir(app, bench_path=bench_path)
-	contents = subprocess.check_output(['git', 'remote', '-v'], cwd=repo_dir,
+	contents = subprocess.check_output(['git', 'remote', '-v'], cwd=repo_dir, stderr=subprocess.STDOUT)
-									   stderr=subprocess.STDOUT)
 	contents = contents.decode('utf-8')
 	if re.findall('upstream[\s]+', contents):
 		return 'upstream'
@@ -371,7 +391,7 @@ def switch_branch(branch, apps=None, bench_path='.', upgrade=False, check_upgrad
 			except CommandFailedError:
 				print("Error switching to branch {0} for {1}".format(branch, app))
 			except InvalidRemoteException:
-				print("Remote does not exist for app "+app)
+				print("Remote does not exist for app {0}".format(app))
 			except InvalidBranchException:
 				print("Branch {0} does not exist in Upstream for {1}".format(branch, app))
 
@@ -382,11 +402,7 @@ def switch_branch(branch, apps=None, bench_path='.', upgrade=False, check_upgrad
 		update_requirements()
 		update_node_packages()
 		pre_upgrade(version_upgrade[1], version_upgrade[2])
-		if sys.version_info >= (3, 4):
+		reload_module(utils)
-			import importlib
-			importlib.reload(utils)
-		else:
-			reload(utils)
 		backup_all_sites()
 		patch_sites()
 		build_assets()
@@ -402,8 +418,7 @@ def switch_to_develop(apps=None, bench_path='.', upgrade=True):
 	switch_branch('develop', apps=apps, bench_path=bench_path, upgrade=upgrade)
 
 def get_version_from_string(contents, field='__version__'):
-	match = re.search(r"^(\s*%s\s*=\s*['\\\"])(.+?)(['\"])(?sm)" % field,
+	match = re.search(r"^(\s*%s\s*=\s*['\\\"])(.+?)(['\"])(?sm)" % field, contents)
-			contents)
 	return match.group(2)
 
 def get_major_version(version):
@@ -427,7 +442,8 @@ def validate_branch():
 		branch = get_current_branch(app)
 
 		if branch == "master":
-			print(''' master branch is renamed to version-11 and develop to version-12. Please switch to new branches to get future updates.
+			print('''master branch is renamed to version-11 and develop to version-12.
+Please switch to new branches to get future updates.
 
 To switch to version 11, run the following commands: bench switch-to-branch version-11''')
 			sys.exit(1)

bench/commands/make.py

@@ -35,10 +35,11 @@ def init(path, apps_path, frappe_path, frappe_branch, no_procfile, no_backups,
 @click.argument('name', nargs=-1) # Dummy argument for backward compatibility
 @click.argument('git-url')
 @click.option('--branch', default=None, help="branch to checkout")
+@click.option('--overwrite' is_flag=True)
 def get_app(git_url, branch, name=None):
 	"clone an app from the internet and set it up in your bench"
 	from bench.app import get_app
-	get_app(git_url, branch=branch)
+	get_app(git_url, branch=branch, overwrite=overwrite)
 
 
 @click.command('new-app')