GEPS 013: Gramps Webapp

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Many Gramps users would like to collaborate or share their genealogy data on the web. This GEP describes a webapp, a web-based application that runs in your browser, and requires a server.

Motivation

The main focus of a Gramps-based webapp is collaboration. The Gramps webapp will allow users to easily move their genealogy data to the web to be seen, and possibly edited, in a collaborative environment.

Here is a small list of goals:

  1. Create a fullscale GRAMPS web framework
  2. Allow multiple users via the standard web browser
    1. Users will log in and have various levels of permissions
  3. Build on GRAMPS codebase and wealth of resources
    1. Reports
    2. Tools
    3. Visualization
  4. Use standards and well-known, well-tested frameworks where possible
    1. WSGI protocol for running code
    2. Django framework

Overview

The Gramps webapp is written in Django. Django is a sophisticated, modern web development framework. Django is written in Python, albeit in a very different style from Gramps. However, part of the motivation of using Django is that it breaks up web development into very clearly defined parts following the Model-View-Controller paradigm. Two of these parts require no special programming knowledge, and thus will allow more people to be able to possibly customize and participate in the Gramps project.

The Gramps webapp (and Django in general) is broken into three well-defined parts:

  1. models/views
  2. templates
  3. CSS (Cascading Style Sheets)

The models define the tables and relationships, but this is done in Python (not SQL). The models also define the API to read/writing/editing the data. The views are also written in Python, and are closely tied to the models. The templates are written in HTML and a template language that is very easy for non-programmers to use and understand. Finally, CSS is just Cascading Style Sheets, where all of the graphical definitions are made. The webapp uses pre-existing CSS created for the "Narrated Web" report of Gramps which was used for created static web pages. Let's take a look at specific examples of each of these parts.

Models/Views

Here is the model that defines the Person table from src/gen/web/grampsdb/models.py:

class Person(PrimaryObject):
    gender_type = models.ForeignKey('GenderType')
    families = models.ManyToManyField('Family', blank=True, null=True)
    parent_families = models.ManyToManyField('Family', 
                                             related_name="parent_families",
                                             blank=True, null=True)
    references = generic.GenericRelation('PersonRef', related_name="refs",
                                         content_type_field="object_type",
                                         object_id_field="object_id")

Here, you can see that Person only has 4 parts: gender_type, families, parent_families, and references. There are are properties, but they are defined in the PrimaryObject class which is shared with other tables. Here is PrimaryObject:

class PrimaryObject(models.Model):
    class Meta: abstract = True
    id = models.AutoField(primary_key=True)
    handle = models.CharField(max_length=19, unique=True)
    gramps_id =  models.CharField('gramps id', max_length=25, blank=True)
    last_saved = models.DateTimeField('last changed', auto_now=True) 
    last_changed = models.DateTimeField('last changed', null=True,
                                        blank=True) # user edits
    private = models.BooleanField('private')
    marker_type = models.ForeignKey('MarkerType')

The big difference here between typical Python programming is that the Person class defines the Person table, and the interface to it. Most Python code would probably have Person be an instance of a class, but Django uses classes to represent many things.

Here are three examples using the Person class:

   >>> self.Person.objects.all()
   [<Person>, <Person>, ...]
   >>> self.Person.get(id=1)
   <Person>
   >>> self.Person.get(handle='gh71234dhf3746347734')
   <Person>

The first retrieves all of the rows for the Person table; the second retrieves just the one record that has the unique, primary key 1, and the third retrieves the single record that has the unique handle of 'gh71234dhf3746347734'.

You can also use the Person interface to select a subset of people:

   >>> self.Person.objects.filter(gender_type=1)
   [<Person>, <Person>, ...]

Templates

Templates are used to describe what to display. Here is a template from src/data/templates/main_page.html:

{% extends "gramps-base.html" %}

{% block title %}GRAMPS Connect - main page {% endblock %}
{% block heading %}GRAMPS - main page {% endblock %}

{% block content %} 

<p id="description">Welcome to GRAMPS Connect, a new web-based collaboration tool.

{% if user.is_authenticated %}
  You are now logged in
  as <a href="/user/{{user.username}}">{{user.username}}</a>.
{% endif %}
</p>

<p id="description">
Database information:
<ul>
{% for view in views %}
   <li><a href="/{{view|lower}}">{{view}}</a></li>
{% endfor %}
</ul>
</p>
{% endblock %}

Finally, here is a screen shot of the main_page.html (above) showing some initial testing of Gramps in Django using the Mainz CSS from the NarrWeb report:

Gramps in django.gif

Getting Started with Gramps in Django

A prototype of a GRAMPS Django webapp is in branches/geps/gep-013-server. To run it, do the following:

  1. Download Django. You'll need version 1.1
    1. On yum-based systems, try "yum install Django"
  2. Checkout the branches/geps/gep-013-server from SVN
    1. cd gramps
    2. svn co https://gramps.svn.sourceforge.net/svnroot/gramps/branches/geps/gep-013-server
    3. This will create a subdirectory here called gep-013-server
  3. cd gep-013-server/src/gen/web/
  4. Edit settings.py
    1. Edit the path to the Sqlite DB (or use another if you wish, including Oracle, MySQL, Postgresql, etc.)
  5. Create the tables, and fill with core data:
    1. make
  6. Run the test webserver:
    1. make run
  7. Point your webbrowser to:
    1. http://127.0.0.1:8000/

At this point, you can now export your Gramps data to Django (and back). In another terminal window:

  1. Build this version of Gramps:
    1. cd gep-013-server/
    2. ./autogen.sh
  2. Start up this version of Gramps
    1. python src/gramps.py
  3. Run the Django Exporter
    1. Select Family Tree -> Export
    2. Select Django

This will export your regular Gramps BSDDB data into whatever Django database you have defined in settings.py above. You now have your data in a SQL database, and can access it via the webbrowser.

To import data back from Django's SQL table back into Gramps from the website:

  1. Create a file named "import.django" somewhere (needs to end in ".django").
  2. Start up this version of Gramps
    1. python src/gramps.py
  3. Run the Django Importer
    1. Select Family Tree -> Import
    2. Select the "import.django" (from above) as the file to import

For more on Django, try their tutorial:

Issues

Concurrent Edits

Concurrent access for write and read imply several problems when people by accident change the same objects at the same time. GRAMPS itself has an elaborate signal handling for cases when dialogs are open with no longer current information. In a web environment, this becomes more difficult however. This is not built into Django.

For discussion on this issue in Django, see:

Example GMS Web Sites

Genealogy Management Systems on the web:

Note here: the intro page is a collection of gadgets/controls, which then link into the real data.