DatasetCrawler¶

Složka obsahuje implementace crawleru pro jednotlivé datasety. Crawlery jsou dynamicky importovány je tedy proto nutné dodržet pojemnování "dataset-name"_crawler.py.

Je velmi žádoucí aby crawler pro stažení souboru používal funkci basic_crawler_functions.download_file_from_url("url_souboru", "jmeno_datasetu").
Ta totiž ukládá do databáze zmínku o tom, které soubory byly již staženy aby nedocházelo k duplicitám nebo zbytečnému stahování.

Generovaný crawler¶

Při použití skriptu PrepareNewDataset.py vznikne následující kostra pro doplnění funkčnosti.

# Path to crawled data
CRAWLED_DATA_PATH = "CrawledData/" 

def crawl(config):
    """ 
    Implement crawl method that downloads new data to path_for_files
    For keeping the project structure
    url , regex, and dataset_name from config
    You can use already implemented functions from Utilities/Crawler/BasicCrawlerFunctions.py

    Args:
        config: loaded configuration file of dataset
    """ 
    dataset_name = config["dataset-name"]
    url = config['url']
    regex = config['regex']
    path_for_files = CRAWLED_DATA_PATH + dataset_name + '/'
    print("You must implements Crawl method first!")

Vzorově implementovaný crawler¶

from Utilities import folder_processor
from Utilities.Crawler import basic_crawler_functions

# Path to crawled data
CRAWLED_DATA_PATH = "CrawledData/" 

def crawl(config):
    """ 
    Implement crawl method that downloads new data to path_for_files
    For keeping the project structure
    url , regex, and dataset_name from config
    You can use already implemented functions from Utilities/Crawler/basic_crawler_functions.py

    Args:
        config: loaded configuration file of dataset
    """ 
    dataset_name = config["dataset-name"]
    url = config['url']
    regex = config['regex']
    path_for_files = CRAWLED_DATA_PATH + dataset_name + '/'

    first_level_links = basic_crawler_functions.get_all_links(url)
    filtered_first_level_links = basic_crawler_functions.filter_links(first_level_links, "^OD_ZCU")
    absolute_first_level_links = basic_crawler_functions.create_absolute_links(filtered_first_level_links, url)

    files = []

    for link in absolute_first_level_links:
        second_level_links = basic_crawler_functions.get_all_links(link)
        filtered_second_level_links = basic_crawler_functions.filter_links(second_level_links, regex)
        absolute_second_level_links = basic_crawler_functions.create_absolute_links(filtered_second_level_links, link)
        final_links = basic_crawler_functions.remove_downloaded_links(absolute_second_level_links, dataset_name)

        for file_link in final_links:
            files.append(file_link)

    for file in files:
        basic_crawler_functions.download_file_from_url(file, dataset_name)

    folder_processor.unzip_all_csv_zip_files_in_folder(path_for_files)