uploader.py

from configparser import ConfigParser
import click
from pathlib import Path
import psycopg2
from typing import List
import yaml

from utils.dataclasses import Module, Resource

'''Set program's verbosity. True to display actions on execution'''
isVerbose = False


def extract_config(filename='database.ini', section='postgresql') -> dict:
    '''Extract all configuration information
    
    :param filename: Path to the .ini configuration file
    :param section: Section from which fetching all postgresql connection data
    
    :return: A dict with all connection parameters
    '''
    if isVerbose:
        print_info('Exctracting posgtres connection data')
    
    # From: https://www.postgresqltutorial.com/postgresql-python/connect/
    # Create a parser
    parser = ConfigParser()
    
    # Read config file
    parser.read(filename)

    # Get section, default to postgresql
    db = {}
    if parser.has_section(section):
        params = parser.items(section)
        for param in params:
            db[param[0]] = param[1]
    else:
        raise Exception(
            'Section {0} not found in the {1} file'.format(section, filename))

    return db


def get_resources(path: Path) -> List[Resource]:
    '''Retrieve all html resources inside the module folder
    
    :param path: Path of the folder in which look for all resources
    
    :return: A list of all found resources as objects
    '''
    if isVerbose:
        print_info('Retrieve existing resource files')
        
    resources: List[Path] = path.glob('**/*.html')
    return [
        Resource(
            content=resource.read_text(encoding='utf8'),
            name=resource.name)
        for resource in resources]


def get_sorted_resources(resources: List[Resource]) -> List[Resource]:
    '''Link all provided resource by alphabetical order
    
    :param resources: The list of all resources to sort
    
    :return: A list of the same resources sorted by alphabetical order
    '''
    if isVerbose:
        print_info('Sort resources')
        
    # Make a copy of all resource
    sorted_resources = resources[:]
    
    # Sort the copy and return it
    sorted_resources.sort(key=lambda resource: resource.name)
    return sorted_resources


def get_module(module: Path) -> Module:
    '''Get module meta data
    
    :param module: Path of the folder in which look for the .yaml module file
    
    :return: The module's data as a Module object
    '''
    if isVerbose:
        print_info('Retrieve module configuration file')
        
    # Get all YAML files
    module_conf_files = [
        file 
        for file in module.glob('**/*')
        if file.is_file() and file.suffix in ['.yml', '.yaml']]
    
    # Assert there is only a unique YAML file for the current module
    if len(module_conf_files) < 1:
        raise FileNotFoundError('No module yaml configuration file found')
    
    if len(module_conf_files) > 1:
        raise FileNotFoundError('Multiple yaml configuration files found for this module')

    return get_module_data(module_conf_files[0])


def get_module_data(module_file: Path) -> Module:
    '''Extract module data from its configuration file'''
    if isVerbose:
        print_info('Extract module\'s data')
        
    # Extract file data
    data = yaml.safe_load(module_file.read_text(encoding='utf8'))
    
    # Assert that each property is present
    if 'module' not in data.keys():
        raise KeyError('Field "module" missing in the module configuration file')
    
    if not all(key in ('name', 'description') for key in data['module']):
        raise KeyError(
            'Unable to read "name" and "description" properties of the module'
            '(are the keys missing ?)')
    
    return Module(**data['module'])


def print_info(message: str) -> None:
    '''Print a debug message
    
    :param message: Message to display
    '''
    print(f'[INFO] {message}')


def record_module(
    module: Module, subscription_plan_id: int,
    config: dict = extract_config()) -> int:
    '''Record the provided module in database
    
    :param module: Module to record in database
    :param subscription_plan_id: Id of its associated subscription plan
    :param config: Postgresql connection parameters
    
    :return: The newly inserted module id
    '''
    if isVerbose:
        print_info(f'Record the module "{module.name}"')
    
    sql = '''
       INSERT INTO "module" ("ModuleDescription", "SubscriptionPlanId", "ModuleName")
       VALUES(%s, %s, %s) RETURNING "Id";
    '''
    
    conn = None
    module_id = 0
    try:
        # Connect to the PostgreSQL database
        conn = psycopg2.connect(**config)
        # Create a new cursor
        cur = conn.cursor()
        # Execute the INSERT statement
        cur.execute(sql, (module.description, subscription_plan_id, module.name))
        # get the generated id back
        module_id = int(cur.fetchone()[0])
        # Commit the changes to the database
        conn.commit()
        # Close communication with the database
        cur.close()
    finally:
        if conn is not None:
            conn.close()
    
    return module_id


def record_resource(
    resource: Resource, module_id: int, next_resource_id: int,
    config: dict = extract_config()) -> int:
    '''Record the provided resource in database
    
    :param resource: Resource to record in database
    :param module_id: Id of the module this resource is related to
    :param next_resource_id: Id of the resource following this one, None if
                             this resource is the last one
    :param config: Postgresql connection parameters
    
    :return: The newly inserted resource id
    '''
    if isVerbose:
        print_info(f'Record the resource from {resource.name}')
    
    sql = '''
       INSERT INTO "resource" ("ModuleId", "Content", "NextResourceId")
       VALUES(%s, %s, %s) RETURNING "Id";
    '''
    conn = None
    resource_id = 0
    try:
        # Connect to the PostgreSQL database
        conn = psycopg2.connect(**config)
        # Create a new cursor
        cur = conn.cursor()
        # Execute the INSERT statement
        cur.execute(sql, (module_id, resource.content, next_resource_id))
        # get the generated id back
        resource_id = int(cur.fetchone()[0])
        # Commit the changes to the database
        conn.commit()
        # Close communication with the database
        cur.close()
    finally:
        if conn is not None:
            conn.close()

    return resource_id


def record_resources(
        resources: List[Resource], module_id: int,
        config: dict = extract_config()) -> None:
    '''Record the provided resources in database
    
    :param resources: The list of all Resource objects to insert
    :param module_id: Id of the module this resource is related to
    :param config: Postgresql connection parameters
    '''
    if isVerbose:
        print_info('Start recording resources')
        
    # Since all resources are linked to each other, we need the index of the
    # second resource to track the first
    # To achieve that, we need to invert the order and start tracking the last
    # which is not linked to any other resource
    resources = resources[::-1]
    
    next_resource_id = None
    for resource in resources:
        next_resource_id = record_resource(resource, module_id, next_resource_id, config)

    if isVerbose:
        print_info('End resources recording')

@click.command()
@click.argument('path', type=click.Path(exists=True))
@click.option(
    '--module',
    '-m',
    'module',
    help='Path to the module description file',
    type=click.Path(exists=True))
@click.option(
    '--subscriptionplan',
    '-s',
    'subscription_plan_id',
    default=1,
    help='Id of the subscription plan to which this module is intended',
    type=int)
@click.option(
    '--verbose',
    is_flag=True,
    help='Set verbosity to True to display actions in the console on execution')
def upload(path, module, subscription_plan_id, verbose):
    '''Upload a module and its resources in the correct order'''
    # Set verbosity level
    global isVerbose
    isVerbose = verbose

    if isVerbose:
        print_info('Start uploading')

    root_path = Path(path)
    
    # Retrieve all resources
    resources: List[Path] = get_resources(root_path)
    
    # Sort and link them
    resources = get_sorted_resources(resources)

    # Retrieve module meta data
    module_path = Path(module if module else path)
    module = get_module(module_path)
    
    # Add a new record for the module
    module_id = record_module(module, subscription_plan_id)
    
    # Add a new track for all its associated resources
    record_resources(resources, module_id)

    if isVerbose:
        print_info('Done !')

if __name__ == "__main__":
    upload()