Flask-WhooshAlchemy is a Flask extension that integrates the text-search functionality of Whoosh with the ORM of SQLAlchemy for use in Flask applications.
Source code and issue tracking at GitHub.
View the official docs here.
pip install flask_whooshalchemy_redux
Or:
git clone https://github.com/dhamaniasad/Flask-WhooshAlchemy.git
Let's set up the environment and create our model:
import flask.ext.whooshalchemy as whooshalchemy
# set the location for the whoosh index
app.config['WHOOSH_BASE'] = 'path/to/whoosh/base'
class BlogPost(db.Model):
__tablename__ = 'blogpost'
__searchable__ = ['title', 'content'] # these fields will be indexed by whoosh
__analyzer__ = SimpleAnalyzer() # configure analyzer; defaults to
# StemmingAnalyzer if not specified
id = app.db.Column(app.db.Integer, primary_key=True)
title = app.db.Column(app.db.Unicode) # Indexed fields are either String,
content = app.db.Column(app.db.Text) # Unicode, or Text
created = db.Column(db.DateTime, default=datetime.datetime.utcnow)
whooshalchemy.whoosh_index(app, BlogPost)
Only two steps to get started:
- Set the
WHOOSH_BASE
to the path for the whoosh index. If not set, it will default to a directory called 'whoosh_index' in the directory from which the application is run. - Add a
__searchable__
field to the model which specifies the fields (asstr
s) to be indexed .
Let's create a post:
db.session.add(
BlogPost(title='My cool title', content='This is the first post.')
); db.session.commit()
After the session is committed, our new BlogPost
is indexed. Similarly, if the post is deleted, it will be removed from the Whoosh index.
To execute a simple search:
results = BlogPost.query.whoosh_search('cool')
This will return all BlogPost
instances in which at least one indexed
field (i.e., 'title' or 'content') is a text match to the query. Results
are ranked according to their relevance score, with the best match
appearing first when iterating. The result of this call is a (subclass
of) sqlalchemy.orm.query.Query object, so you can chain other SQL
operations. For example:
two_days_ago = datetime.date.today() - datetime.timedelta(2)
recent_matches = BlogPost.query.whoosh_search('first').filter(
BlogPost.created >= two_days_ago)
Or, in alternative (likely slower) order:
recent_matches = BlogPost.query.filter(
BlogPost.created >= two_days_ago).whoosh_search('first')
We can limit results:
# get 2 best results:
results = BlogPost.query.whoosh_search('cool', limit=2)
By default, the search is executed on all of the indexed fields as an OR
conjunction. For example, if a model has 'title' and 'content' indicated
as __searchable__
, a query will be checked against both fields,
returning any instance whose title or content are a content match for
the query. To specify particular fields to be checked, populate the
fields
parameter with the desired fields:
results = BlogPost.query.whoosh_search('cool', fields=('title',))
By default, results will only be returned if they contain all of the
query terms (AND). To switch to an OR grouping, set the or_
parameter
to True
:
results = BlogPost.query.whoosh_search('cool', or_=True)