Use return of one method in another method of the same class

Question

I am working with The Guardian API, through two methods, search_content() and data_to_csv(), contained in the Theguardian class. The first method is responsible for searching The Guardian database according to the given parameters, while the second method consolidates the data collected in the search into a CSV file.

My question is this, the method search_content() returns the variable json_content, which is a dictionary containing the response package coming from the search. However, I am unable to access the dictionary in the method data_to_csv(). As can be seen below:

>>> from script_guardian import TheGuardian
>>> tg = TheGuardian('2016-01-01', '2018-01-01')
>>> json_content = tg.search_content('education', 'relevance', 'education')
>>> json_content
<bound method Content.get_content_response of <theguardian.theguardian_content.Content object at 0x7f7bb9764c88>>
>>> type(json_content)
<class 'method'>

That is, the return of the method search_content() is <class 'method'> instead of Dict.

I believe this problem is due to the way I organized my methods. If at the time of instantiating the object, I execute the method data_to_csv(), I can update the csv file in this way:

tg.data_to_csv(search_content())

I would like to know how I can organize my code in order to execute the methods, at the time of creation of the object, only with the parameters 'data_initial' and 'data_final'. That is to say,

tg = TheGuardian('yyyy-mm-dd','yyyy-mm-dd')

I believe this can be configured in __init__, but I don’t know how.

Doubts:

• How to automatically execute methods when creating object?
• How to receive json_content in the method data_to_csv() in the Dict format, instead of the method itself?

My code:

from theguardian import theguardian_content
import csv


class TheGuardian(object):
    '''Metodos para busca e conversao de dados na base do The Guardian'''

    def __init__(self, data_inicial, data_final):
        '''
        Inicializacao da instancia

        Args:
            data_inicial(str): data no formato ISO 8601
            data_final(str): data no formato ISO 8601
        '''
        self.data_inicial = data_inicial
        self.data_final = data_final
        self.data_to_csv(self.search_content())

    def search_content(self, content='education', order_by='relevance',
                       section='education', api_key='test', page_size=10):
        '''
        Metodo responsavel por buscar na base de dados do The Guardian

        Args:
            content(str): as noticias serao relacionadas ao assunto informado
            page_size(str): noticias retornadas por pagina
            order_by(int): ordenacao das noticias, pode ser 'newest',
                           'relevance' e 'oldest'.
            api_key(str): chave da API a ser utilizada
            section(str): secao referente as noticias a serem retornadas

        Returns:
            json_content(dict): pacote de resposta da busca performada
        '''

        self.content = content
        self.page_size = page_size
        self.order_by = order_by
        self.api_key = api_key
        self.section = section

        # Parametros de busca
        params = {
            'data_inicial': self.data_inicial,
            'data_final': self.data_final,
            'order-by': self.order_by,
            'page-size': self.page_size,
            'q': self.content,
            'api': self.api_key,
            'section': self.section
        }

        content = theguardian_content.Content(**params)
        self.json_content = content.get_content_response


    def data_to_csv(self, json_content):
        '''
        Conversao do pacote de resposta da busca em arquivo no formato CSV

        Note:
            Arquivo guardian_data.csv sera reescrito apos cada consulta na API

        Args:
            json_content(dict): conteudo retornado a partir dos parametros de
                                busca informados anteriormente

        Returns:
            guardian_data(csv): consolidacao dos dados consultado na API
        '''

        with open('guardian_data.csv', 'w') as csv_file:
            writer = csv.writer(csv_file, delimiter=',')

            # Escricao do cabecalho do arquivo CSV
            writer.writerow(["webUrl", "webPublicationDate", "webTitle",
                             "sectionName", "apiUrl", "id", "isHosted",
                             "sectionId", "type", "pillarId", "pillarName"])

            for result in self.json_content['response']['results']:
                writer.writerow([
                    result["webUrl"],
                    result["webPublicationDate"],
                    result["webTitle"],
                    result["sectionName"],
                    result["apiUrl"],
                    result["id"],
                    result["isHosted"],
                    result["sectionId"],
                    result["type"],
                    result["pillarId"],
                    result["pillarName"]
                ])

Answer 1

You could play the output of one method at the entrance of the other but this is not very pretty (like, the information comes out of the object and then goes in). Oh yes, to execute methods when creating an object just call them inside the constructor, the __init__().

Since json_content is a class attribute, initialize it within __init__() with self.json_content = {}. Finalize the method search_content() with self.json_content = content.get_content_response() and alters data_to_csv() not to receive other parameters than self and remove the self.json_content = json_content.