Your first local Lino project¶
In this tutorial we are going to have a deeper look at what happened when you installed Lino as described in Installing a Lino developer environment.
Project directories¶
-
~/lino/lino_local
¶
This is your projects root, which will hold all the Lino sites on your computer. Lino project directories are not very big, and you will hopefully create many such projects and want to keep a backup of them.
-
~/lino/lino_local/first
¶
The project directory of the first site you created in Installing a Lino developer environment.
- Django project directory
A directory that contains a runnable Django project. It contains the files necessary for that specific instance of a given Lino application. Usually there is one Django project directory for every Lino site. An exception to that rule is a site with more than one front end.
The settings.py
file¶
Your first settings.py
file should look as follows:
from lino_book.projects.min2.settings import *
SITE = Site(globals(), title="My Lino site")
DEBUG = True
Explanations:
lino_book.projects.min1
is one of the out-of-the-box projects included in the Lino Book. Actually it is the first of a series of projects which is documented in The Lino Minimal projects.We import these settings directly into our global namespace using the wildcard
*
. This is necessary because that's how Django wants settings.Then comes the important trick which turns your Django project into a Lino application:
SITE = Site(globals(), ...)
That is, you instantiate a
Site
class and store this object asSITE
in your Django settings. This line will automatically install default values for all required Django settings (e.g.DATABASES
andLOGGING
) into your global namespace.
You might add DEBUG = True
or other settings of your choice
after these two lines, but it is not necessary here.
More about this in Lino and your Django settings.
The manage.py
file¶
Now add a manage.py
file with the following content:
#!/usr/bin/env python
import os
import sys
if __name__ == "__main__":
os.environ["DJANGO_SETTINGS_MODULE"] = "settings"
from django.core.management import execute_from_command_line
execute_from_command_line(sys.argv)
A manage.py
does two things: it sets the
DJANGO_SETTINGS_MODULE
environment variable and then calls
Django's execute_from_command_line function.
This is plain traditional Django know-how. There are many opinions,
tricks, flavors and conventions about Django's manage.py
files, partly for historical reasons. Lino does not add any tricks to
the manage.py
file, so you can use your own flavour if you
prefer.
Loading initial data into your database¶
Next we create your database and populate it with some demo content. With a Lino application this is easier than with a plain Django project, it is just one command to type:
$ python manage.py prep
The prep
command is a custom django-admin command
provided by Lino. It is just a thin wrapper which calls initdb
with
the application's Demo fixtures as argument. It will ask you:
INFO Started manage.py prep (using settings) --> PID 28463
We are going to flush your database (.../default.db).
Are you sure (y/n) ?
If you answer "y" here, then Lino will delete everything in the given
database and replace it with its "factory default" demo data. Yes,
that's what we want. So go on and type y
.
The output that follows should look like this:
>>> shell("python manage.py prep --noinput")
...
`initdb std demo demo2` started on database .../hello/default.db.
Operations to perform:
Synchronize unmigrated apps: about, bootstrap3, cal, checkdata, contacts, countries, export_excel, extjs, gfks, jinja, lino, office, printing, staticfiles, system, users, xl
Apply all migrations: contenttypes, sessions
Synchronizing apps without migrations:
Creating tables...
Creating table system_siteconfig
Creating table users_user
Creating table users_authority
Creating table countries_country
Creating table countries_place
Creating table contacts_partner
Creating table contacts_person
Creating table contacts_companytype
Creating table contacts_company
Creating table contacts_roletype
Creating table contacts_role
Creating table gfks_helptext
Creating table checkdata_problem
Creating table cal_remotecalendar
Creating table cal_room
Creating table cal_eventtype
Creating table cal_guestrole
Creating table cal_calendar
Creating table cal_subscription
Creating table cal_task
Creating table cal_eventpolicy
Creating table cal_recurrentevent
Creating table cal_event
Creating table cal_guest
Running deferred SQL...
Running migrations:
Applying contenttypes.0001_initial... OK
Applying contenttypes.0002_remove_content_type_name... OK
Applying sessions.0001_initial... OK
Loading data from .../lino_xl/lib/contacts/fixtures/std.py
Loading data from .../lino/modlib/gfks/fixtures/std.py
Loading data from .../lino_xl/lib/cal/fixtures/std.py
Loading data from .../lino/modlib/users/fixtures/demo.py
Loading data from .../lino_xl/lib/countries/fixtures/demo.py
Loading data from .../lino_xl/lib/contacts/fixtures/demo.py
Loading data from .../lino_xl/lib/cal/fixtures/demo.py
Loading data from .../lino/modlib/users/fixtures/demo2.py
Loading data from .../lino_xl/lib/cal/fixtures/demo2.py
Installed ... object(s) from ... fixture(s)
Lino applications make abundant use of what we call Python fixtures in order to have a rich set of "demo data". We will come back to this in The initdb command.
Start the web server¶
Now you can invoke runserver
to start the development
server:
$ python manage.py runserver
which should output something like:
Validating models...
0 errors found
Django version 1.4.5, using settings 'hello.settings'
Development server is running at http://127.0.0.1:8000/
Quit the server with CTRL-BREAK.
And then point your web browser to http://127.0.0.1:8000 and you should see something like this:

Congratulations! Enjoy the first Lino application that exists only on your machine!
Visualizing database content from the command-line¶
The runserver
command starts a web server and lets you
interact with the database through the web interface. But Django also
offers a shell
interface.
We will come back to this later, for the moment just try the following.
You can visualize the content of your database from the command-line
without starting a web server using Lino's show
command.
For example to see the list of countries, you can write:
>>> shell("python manage.py show countries.Countries")
...
============================= ==========
Designation ISO code
----------------------------- ----------
Belgium BE
Congo (Democratic Republic) CD
Estonia EE
France FR
Germany DE
Maroc MA
Netherlands NL
Russia RU
============================= ==========
Exercises¶
You can now play around by changing things in your project.
In your
settings.py
file, replacelino_book.projects.min2
bylino_book.projects.liina
. Run python manage.py prep followed by python manage.py runserver. Log in and play around.Same as previous, but with
lino_book.projects.chatter
Write three descriptions (e.g. in LibreOffice .odt format), one for each of the applications you just saw: what it can do, what are the features, what functionalities are missing. Use screenshots. Use a language which can be understood by non-programmers. Send these documents to your mentor.
Read the documentation about the following Site attributes and try to change them:
languages
Hint: There are two possibilities to change Site attributes. The most basic way is:
from lino_book.projects.chatter.settings import * SITE = Site(globals(), title="My Lino site", is_demo_site=False, languages="en fr") DEBUG = True
The recommended way on production sites is this:
from lino_book.projects.chatter.settings import * class Site(Site): title = "My Lino site" is_demo_site = False languages = "en fr" SITE = Site(globals()) DEBUG = True
See Lino and your Django settings for more explanations.