def register():
form = RegistrationForm()
username_not_unique = None
if form.validate_on_submit():
# Successful POST, i.e. the username and password have passed validation checking.
# Use the service layer to attempt to add the new user.
try:
services.add_user(form.username.data, form.password.data, repo.repo_instance)
# All is well, redirect the user to the login page.
return redirect(url_for('authentication_bp.login'))
except services.NameNotUniqueException:
username_not_unique = 'Your username is already taken - please supply another'
# For a GET or a failed POST request, return the Registration Web page.
return render_template(
'authentication/credentials.html',
title='Register',
form=form,
username_error_message=username_not_unique,
handler_url=url_for('authentication_bp.register'),
selected_articles=utilities.get_selected_articles(),
tag_urls=utilities.get_tags_and_urls()
)
def comment_on_article():
# Obtain the username of the currently logged in user.
username = session['username']
# Create form. The form maintains state, e.g. when this method is called with a HTTP GET request and populates
# the form with an article id, when subsequently called with a HTTP POST request, the article id remains in the
# form.
form = CommentForm()
if form.validate_on_submit():
# Successful POST, i.e. the comment text has passed data validation.
# Extract the article id, representing the commented article, from the form.
article_id = int(form.article_id.data)
# Use the service layer to store the new comment.
services.add_comment(article_id, form.comment.data, username,
uow.uow_instance)
# Retrieve the article in dict form.
article = services.get_article(article_id, uow.uow_instance)
# Cause the web browser to display the page of all articles that have the same date as the commented article,
# and display all comments, including the new comment.
return redirect(
url_for('news_bp.articles_by_date',
date=article['date'],
view_comments_for=article_id))
if request.method == 'GET':
# Request is a HTTP GET to display the form.
# Extract the article id, representing the article to comment, from a query parameter of the GET request.
article_id = int(request.args.get('article'))
# Store the article id in the form.
form.article_id.data = article_id
else:
# Request is a HTTP POST where form validation has failed.
# Extract the article id of the article being commented from the form.
article_id = form.article_id.data
# For a GET or an unsuccessful POST, retrieve the article to comment in dict form, and return a Web page that allows
# the user to enter a comment. The generated Web page includes a form object.
article = services.get_article(article_id, uow.uow_instance)
return render_template('news/comment_on_article.html',
title='Edit article',
article=article,
form=form,
handler_url=url_for('news_bp.comment_on_article'),
selected_articles=utilities.get_selected_articles(),
tag_urls=utilities.get_tags_and_urls())
def login():
form = LoginForm()
username_not_recognised = None
password_does_not_match_username = None
if form.validate_on_submit():
# Successful POST, i.e. the username and password have passed validation checking.
# Use the service layer to lookup the user.
try:
user = services.get_user(form.username.data, repo.repo_instance)
# Authenticate user.
services.authenticate_user(user['username'], form.password.data, repo.repo_instance)
# Initialise session and redirect the user to the home page.
session.clear()
session['username'] = user['username']
return redirect(url_for('home_bp.home'))
except services.UnknownUserException:
# Username not known to the system, set a suitable error message.
username_not_recognised = 'Username not recognised - please supply another'
except services.AuthenticationException:
# Authentication failed, set a suitable error message.
password_does_not_match_username = '******'
# For a GET or a failed POST, return the Login Web page.
return render_template(
'authentication/credentials.html',
title='Login',
username_error_message=username_not_recognised,
password_error_message=password_does_not_match_username,
form=form,
selected_articles=utilities.get_selected_articles(),
tag_urls=utilities.get_tags_and_urls()
)
def articles_by_tag():
articles_per_page = 3
# Read query parameters.
tag_name = request.args.get('tag')
cursor = request.args.get('cursor')
article_to_show_comments = request.args.get('view_comments_for')
if article_to_show_comments is None:
# No view-comments query parameter, so set to a non-existent article id.
article_to_show_comments = -1
else:
# Convert article_to_show_comments from string to int.
article_to_show_comments = int(article_to_show_comments)
if cursor is None:
# No cursor query parameter, so initialise cursor to start at the beginning.
cursor = 0
else:
# Convert cursor from string to int.
cursor = int(cursor)
# Retrieve article ids for articles that are tagged with tag_name.
article_ids = services.get_article_ids_for_tag(tag_name, uow.uow_instance)
# Retrieve the batch of articles to display on the Web page.
articles = services.get_articles_by_id(
article_ids[cursor:cursor + articles_per_page], uow.uow_instance)
first_article_url = None
last_article_url = None
next_article_url = None
prev_article_url = None
if cursor > 0:
# There are preceding articles, so generate URLs for the 'previous' and 'first' navigation buttons.
prev_article_url = url_for('news_bp.articles_by_tag',
tag=tag_name,
cursor=cursor - articles_per_page)
first_article_url = url_for('news_bp.articles_by_tag', tag=tag_name)
if cursor + articles_per_page < len(article_ids):
# There are further articles, so generate URLs for the 'next' and 'last' navigation buttons.
next_article_url = url_for('news_bp.articles_by_tag',
tag=tag_name,
cursor=cursor + articles_per_page)
last_cursor = articles_per_page * int(
len(article_ids) / articles_per_page)
if len(article_ids) % articles_per_page == 0:
last_cursor -= articles_per_page
last_article_url = url_for('news_bp.articles_by_tag',
tag=tag_name,
cursor=last_cursor)
# Construct urls for viewing article comments and adding comments.
for article in articles:
article['view_comment_url'] = url_for('news_bp.articles_by_tag',
tag=tag_name,
cursor=cursor,
view_comments_for=article['id'])
article['add_comment_url'] = url_for('news_bp.comment_on_article',
article=article['id'])
# Generate the webpage to display the articles.
return render_template('news/articles.html',
title='Articles',
articles_title='Articles tagged by ' + tag_name,
articles=articles,
selected_articles=utilities.get_selected_articles(
len(articles) * 2),
tag_urls=utilities.get_tags_and_urls(),
first_article_url=first_article_url,
last_article_url=last_article_url,
prev_article_url=prev_article_url,
next_article_url=next_article_url,
show_comments_for_article=article_to_show_comments)
def articles_by_date():
# Read query parameters.
target_date = request.args.get('date')
article_to_show_comments = request.args.get('view_comments_for')
# Fetch the first and last articles in the series.
first_article = services.get_first_article(uow.uow_instance)
last_article = services.get_last_article(uow.uow_instance)
if target_date is None:
# No date query parameter, so return articles from day 1 of the series.
target_date = first_article['date']
else:
# Convert target_date from string to date.
target_date = date.fromisoformat(target_date)
if article_to_show_comments is None:
# No view-comments query parameter, so set to a non-existent article id.
article_to_show_comments = -1
else:
# Convert article_to_show_comments from string to int.
article_to_show_comments = int(article_to_show_comments)
# Fetch article(s) for the target date. This call also returns the previous and next dates for articles immediately
# before and after the target date.
articles, previous_date, next_date = services.get_articles_by_date(
target_date, uow.uow_instance)
first_article_url = None
last_article_url = None
next_article_url = None
prev_article_url = None
if len(articles) > 0:
# There's at least one article for the target date.
if previous_date is not None:
# There are articles on a previous date, so generate URLs for the 'previous' and 'first' navigation buttons.
prev_article_url = url_for('news_bp.articles_by_date',
date=previous_date.isoformat())
first_article_url = url_for('news_bp.articles_by_date',
date=first_article['date'].isoformat())
# There are articles on a subsequent date, so generate URLs for the 'next' and 'last' navigation buttons.
if next_date is not None:
next_article_url = url_for('news_bp.articles_by_date',
date=next_date.isoformat())
last_article_url = url_for('news_bp.articles_by_date',
date=last_article['date'].isoformat())
# Construct urls for viewing article comments and adding comments.
for article in articles:
article['view_comment_url'] = url_for(
'news_bp.articles_by_date',
date=target_date,
view_comments_for=article['id'])
article['add_comment_url'] = url_for('news_bp.comment_on_article',
article=article['id'])
# Generate the webpage to display the articles.
return render_template(
'news/articles.html',
title='Articles',
articles_title=target_date.strftime('%A %B %e %Y'),
articles=articles,
selected_articles=utilities.get_selected_articles(
len(articles) * 2),
tag_urls=utilities.get_tags_and_urls(),
first_article_url=first_article_url,
last_article_url=last_article_url,
prev_article_url=prev_article_url,
next_article_url=next_article_url,
show_comments_for_article=article_to_show_comments)
# No articles to show, so return the homepage.
return redirect(url_for('home_bp.home'))
def home():
return render_template('home/home.html',
selected_articles=utilities.get_selected_articles(),
tag_urls=utilities.get_tags_and_urls())