Saving / accessing fields from Class methods (Django) - django

Question

Appologies for the beginner question and/or stupidity - I'm learning as I go.... I'm trying to pass a user entered url of a PubMed article to access the metadata for that article. I'm using the following code, but I cannot access anything form the save method in he 'Entry' model. For example in my html form I can display {{entry.date_added }} in a form but not {{ entry.title}}. I suspect it's a simple answer but not obvious to me. Thanks for any help.
models.py
from django.db import models
from django.contrib.auth.models import User
import pubmed_lookup
from django.utils.html import strip_tags
class Topic(models.Model):
"""Broad topic to house articles"""
text = models.CharField(max_length=200)
date_added = models.DateTimeField(auto_now_add=True)
owner = models.ForeignKey(User, on_delete=models.CASCADE)
def __str__(self):
"""Return a string representation of the model"""
return self.text
class Entry(models.Model):
"""Enter and define article from topic"""
topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
pub_med_url = models.URLField(unique=True)
date_added = models.DateTimeField(auto_now_add=True)
def save(self, *args, **kwargs):
query = self.pub_med_url
email = "david.hallsworth#hotmail.com"
lookup = pubmed_lookup.PubMedLookup(query, email)
publication = pubmed_lookup.Publication(lookup)
self.title = strip_tags(publication.title)
self.authors = publication.authors
self.first_author = publication.first_author
self.last_author = publication.last_author
self.journal = publication.journal
self.year = publication.year
self.month = publication.month
self.day = publication.day
self.url = publication.url
self.citation = publication.cite()
self.mini_citation = publication.cite_mini()
self.abstract = strip_tags(publication.abstract)
super().save(*args, **kwargs)
class Meta:
verbose_name_plural = 'articles'
def __str__(self):
return "{} - {} - {} - {} [{}]".format(self.year,
self.first_author, self.journal, self.title, str(self.pmid), )

Answer 1

In Django ORM, you have to manually specify all fields that need to be saved. Simply saving it as self.foo = bar in the save method is stored in the Entry instance object (=in memory), but not in the database. That is, there is no persistence. Specify all the fields that need to be saved in the model and run python manage.py makemigrations,python manage.py migrate. Assigning fields to the model is actually the task of designing the relational database.
class Entry(models.Model):
"""Enter and define article from topic"""
topic = models.ForeignKey(Topic, on_delete=models.CASCADE)
pub_med_url = models.URLField(unique=True)
date_added = models.DateTimeField(auto_now_add=True)
title = models.CharField(...)
authors = models.CharField(...)
...
def assign_some_data_from_pubmed(self):
email = "david.hallsworth#hotmail.com"
lookup = pubmed_lookup.PubMedLookup(query, email)
publication = pubmed_lookup.Publication(lookup)
self.title = strip_tags(publication.title)
self.authors = publication.authors
self.first_author = publication.first_author
self.last_author = publication.last_author
self.journal = publication.journal
self.year = publication.year
self.month = publication.month
self.day = publication.day
self.url = publication.url
self.citation = publication.cite()
self.mini_citation = publication.cite_mini()
self.abstract = strip_tags(publication.abstract)
Usage:
entry = Entry(...)
entry.assign_some_data_from_pubmed()
entry.save()