lostplaces-backend/django_lostplaces/docs/developer.md

# django lostplaces documentation for developer

Greetings,
this documentation is for anyone who wants to work with this projects codebase or is just curious about our project.


## Models
The models contain an custom user profile, some abstract base models and the models holding the actual data for this project


### Explorer user profile
The class `lostplaces.models.Explorer` is our custom user profile. It has an ForeignKey pointing at django's default user model instead of providing an entire custom user model. That way this django app does not conflict with any other app that has to bring it's own user model.

You can access the explorer profile by accessing the 'explorer' attribute of any user instance
```python
user.explorer
```

Currently the explorer profile is used by the abstract model 'Submittable' and thus referenced by 'Place' and 'PlaceImage'. The explorer profile therefore has two attributes
```python
user.explorer.places
user.explorer.placeimages
```
`places`  
A list containing all (lost) places the user has submitted  
`placeimages`  
A list containing all images relating a place that a user has submitted


### Taggable
The abstract model Taggable represents an model that is taggable. It depends on the django app [taggit](https://github.com/jazzband/django-taggit). It only consists of one field:  
`tag`  
TaggableManager, allows the sub class to be tagged, blank=True allows the admin form to be submitted without any tags


### Mapable
The abstract model Mapable represents an model that can be displayed on a map. It consists of tree members  
`name`  
Name of the object, displayed on the map, max length 50 characters  
`latitude`  
Latitude of the referenced location, -90 <= value <= 90  
`longitude`  
Longitude of the referenced location  -180 <= value <= 180  
A mapable model has to provide its own get_absolute_url, in order to provide a link when clicked.


### Submittable
The abstract model Submittable represents an model that can be submitted by an user. It knows who submitted something and when:  
`submitted_by`  
Referencing the explorer profile, see [Explorer](##explorer-user-profile). If the explorer profile is deleted, this instance is kept (on_delete=models.SET_NULL). The related_name is set to the class name, lower case appending an s (%(class)s)  
`submitted_when`  
When the object was submitted, automatically set by django (auto_now_add=True)


### Voucher
A voucher code is needed to sign up using lostplaces sign up form. The model contains  
`code`  
The voucher code, max length 30 characters
`created_when`  
When the voucher was created automatically set by django (auto_now_add=True)  
`expires_when`  
Till what date the voucher remains valid


### Place
The place model is the heart of this project. It stores all information about a place needed.  
`location`  
Human readable location description (town, village, street), max length 50 characters  
`description`  
Describing the place in detail  
The place model uses these abstract super classes
- Submittable, see [Submittable](##submittable) for additional fields
- Taggable, see [Taggable](##taggable) for additional fields
- Mapable, see [Mapable](##mapable) for additional fields
The average_latlon function takes a list of places and returns the center point of all these places