litmus/contribute/developer_guide/generate_chart.py

182 lines
7.9 KiB
Python

from jinja2 import Environment, FileSystemLoader, select_autoescape
import yaml
import os
import sys
import argparse
'''
TODO:
1. No try-catch blocks have been used to account for empty/uninitialized params in attributes.yaml
2. Add basic unit/bdd tests (manually checked currently) & necessary code refactor to facilitate this:
a. (positive) Verify creation of CSV for --generate_type=chart
b. (positive) Verify creation of CSV using category name for --generate_type=experiment
c. (positive) Verify creation of business logic, job & experiment CRs for --generate_type=experiment
d. (negative) Verify validation/err-handle upon empty name, category attributes
'''
'''
NOTES:
1. Category attribute is expected to match with chart names(though not mandatory), as per convention
followed in litmuschaos/chaos-charts
'''
# generate_csv creates the chartserviceversion manifest
def generate_csv(csv_parent_path, csv_name, csv_config, litmus_env):
csv_filename = csv_parent_path + '/' + csv_name + '.' + 'chartserviceversion.yaml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/chartserviceversion.tmpl')
output_from_parsed_template = template.render(csv_config)
with open(csv_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_chart creates the experiment-custom-resource manifest
def generate_chart(chart_parent_path, chart_config, litmus_env):
chart_filename = chart_parent_path + '/' + 'experiment.yaml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_custom_resource.tmpl')
output_from_parsed_template = template.render(chart_config)
with open(chart_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_rbac creates the rbac for the experiment
def generate_rbac(chart_parent_path, chart_config, litmus_env):
rbac_filename = chart_parent_path + '/' + 'rbac.yaml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_rbac.tmpl')
output_from_parsed_template = template.render(chart_config)
with open(rbac_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_engine creates the chaos engine for the experiment
def generate_engine(chart_parent_path, chart_config, litmus_env):
engine_filename = chart_parent_path + '/' + 'engine.yaml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_engine.tmpl')
output_from_parsed_template = template.render(chart_config)
with open(engine_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_job creates the experiment job manifest
def generate_job(job_parent_path, job_name, job_config, litmus_env):
job_filename = job_parent_path + '/' + job_name + '_' + 'k8s_job.yml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_k8s_job.tmpl')
output_from_parsed_template = template.render(job_config)
with open(job_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_ansible_logic creates the ansible_logic manifest
def generate_ansible_logic(ansible_logic_parent_path, ansible_logic_name, ansible_logic_config, litmus_env):
ansible_logic_filename = ansible_logic_parent_path + '/' + ansible_logic_name + '_' + 'ansible_logic.yml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_ansible_logic.tmpl')
output_from_parsed_template = template.render(ansible_logic_config)
with open(ansible_logic_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_chaos_prerequisites creates the chaos_prerequisites manifest
def generate_chaos_prerequisites(chaos_prerequisites_parent_path, chaos_prerequisites_name, chaos_prerequisites_config, litmus_env):
chaos_prerequisites_filename = chaos_prerequisites_parent_path + '/' + chaos_prerequisites_name + '_' + 'ansible_prerequisites.yml'
# Load Jinja2 template
template = litmus_env.get_template('./templates/experiment_ansible_prerequisites.tmpl')
output_from_parsed_template = template.render(chaos_prerequisites_config)
with open(chaos_prerequisites_filename, "w+") as f:
f.write(output_from_parsed_template)
# generate_package creates the package manifest
def generate_package(package_parent_path, package_name):
package_filename = package_parent_path + '/' + package_name + '.' + 'package.yaml'
print(package_filename)
with open(package_filename, "w+") as f:
f.write('packageName: ' + package_name + '\n' + 'experiments:')
def main():
# Required Arguments
parser = argparse.ArgumentParser()
parser.add_argument("-a", "--attributes_file", required=True,
help="metadata to generate chartserviceversion yaml")
parser.add_argument("-t", "--generate_type", required=True,
help="scaffold a new chart or experiment into existing chart")
# Optional Arguments
parser.add_argument("-c", "--chart_name", required=False,
help="existing chart name to which experiment belongs, defaults to 'category' in attributes file")
args = parser.parse_args()
entity_metadata_source = args.attributes_file
entity_type = args.generate_type
entity_parent = args.chart_name
# Load data from YAML file into a dictionary
config = yaml.load(open(entity_metadata_source))
entity_name = config['name']
# Store the litmus root from bootstrap folder
litmus_root = os.path.abspath(os.path.join("..", os.pardir))
#env = Environment(loader = FileSystemLoader('./'), trim_blocks=True, lstrip_blocks=True, autoescape=True)
env = Environment(loader = FileSystemLoader('./'), trim_blocks=True, lstrip_blocks=True, autoescape=select_autoescape(['yaml']))
# if generate_type is chart, only create the chart(top)-level CSV & package manifests
if entity_type == 'chart':
chart_dir = litmus_root + '/experiments/' + entity_name
if os.path.isdir(chart_dir) != True:
os.makedirs(chart_dir)
generate_csv(chart_dir, entity_name, config, env)
generate_package(chart_dir, entity_name)
# if generate_type is experiment, create the litmusbook arefacts (job, playbook, cr)
elif entity_type == 'experiment':
# if chart_name is not explicitly provided, use "category" from attributes.yaml as chart
if entity_parent is None:
experiment_category = config['category']
chart_dir = litmus_root + '/experiments/' + experiment_category
else:
chart_dir = litmus_root + '/experiments/' + entity_parent
# if a folder with specified/derived chart name is not present, create it
if os.path.isdir(chart_dir) != True:
os.makedirs(chart_dir)
# generate csv for the freshly created chart folder
generate_csv(chart_dir, experiment_category, config, env)
# generate package for the freshly created chart folder
generate_package(chart_dir, experiment_category)
# create experiment folder inside the chart folder
experiment_dir = chart_dir + '/' + entity_name
if os.path.isdir(experiment_dir) != True:
os.makedirs(experiment_dir)
# generate experiment csv
generate_csv(experiment_dir, entity_name, config, env)
# generate experiment-custom-resource
generate_chart(experiment_dir, config, env)
# generate experiment specific rbac
generate_rbac(experiment_dir, config, env)
# generate experiment specific chaos engine
generate_engine(experiment_dir, config, env)
# generate experiment job
generate_job(experiment_dir, entity_name, config, env)
# generate chaos-ansible-logic
generate_ansible_logic(experiment_dir, entity_name, config, env)
# generate chaos-prerequisites
generate_chaos_prerequisites(experiment_dir, entity_name, config, env)
if __name__=="__main__":
main()