Nodes¶

nodeshot.core.nodes is the core geographic app of nodeshot.

Nodes have the following features:

geometry can be a Point, a Polygon or a Linestring

have to belong to a Layer if nodeshot.core.layers is enabled (which it is by default)

have a status, which can be customized in the admin, by default statuses are potential, active, planned

have other properties like description, address, ecc.

can have custom properties by leveraging the NODESHOT_NODES_HSTORE_SCHEMA setting

Other modules extend the Node object and add several functionalities like comments, votes, ecc.

Additional features:

Possibility to customize the default node schema by adding custom fields

Set the default status of nodes from admin

Nodes can be published by default or not

Nodes may store descriptions in HTML format

Elevation API, a proxy to Google Elevation API, default URL is at /api/v1/elevation/

Available settings¶

nodeshot.core.nodes is enabled by default in nodeshot.conf.settings.INSTALLED_APPS.

These are the available customizable settings:

NODESHOT_NODES_HSTORE_SCHEMA

NODESHOT_NODES_PUBLISHED_DEFAULT

NODESHOT_NODES_REVERSION_ENABLED

NODESHOT_NODES_HTML_DESCRIPTION

NODESHOT_GOOGLE_ELEVATION_API_KEY

NODESHOT_GOOGLE_ELEVATION_DEFAULT_SAMPLING

NODESHOT_NODES_HSTORE_SCHEMA¶

default: None

NODESHOT_NODES_HSTORE_SCHEMA: custom django-hstore schema to add new fields on the Node model and API.

The following example will add a choice field with a select of 3 choices:

# settings.py

NODESHOT_NODES_HSTORE_SCHEMA = [
    {
        'name': 'choice',
        'class': 'CharField',
        'kwargs': {
            'max_length': 128,
            'choices': [
                ('choice1', 'Choice 1'),
                ('choice2', 'Choice 2'),
                ('choice3', 'Choice 3')
            ],
            'default': 'choice1'
        }
    }
]

Consult the django-hstore documentation for more information (look for schema mode).

NODESHOT_NODES_PUBLISHED_DEFAULT¶

default: True

Whether the default value for the “is_published” field on new nodes will be True or False.

Use False if you want new nodes to be reviewed by an admin before showing publicly on the site.

NODESHOT_NODES_REVERSION_ENABLED¶

default: True

Indicates whether the Node model can revert changes saved in the history by using django-reversion.

NODESHOT_NODES_HTML_DESCRIPTION¶

default: True

Indicates whether the “description” field of the Node model allows HTML or not.

If True an WYSIWYG editor will be used in the admin site.

NODESHOT_GOOGLE_ELEVATION_API_KEY¶

default: None

API key of the Google Elevation API.

This setting is optional, but registering an API key is recommended by Google.

See the Google Elevation API documentation for more information.

NODESHOT_GOOGLE_ELEVATION_DEFAULT_SAMPLING¶

default: 50

Warning

Setting a very low value may cause the reach of the usage limits of the Google Elevation API.

Calculates automatic sampling to get one point every x meters, where x is the value specified in NODESHOT_GOOGLE_ELEVATION_DEFAULT_SAMPLING.

A bit more explaination is needed: when sending sampled path requests to the Google Elevation API a samples parameter is required:

Note

samples (required) specifies the number of sample points along a path for which to return elevation data. The samples parameter divides the given path into an ordered set of equidistant points along the path.

If no samples parameter is specified in the HTTP request to the elevation API resource, nodeshot will take care of it automatically, ensuring there are enough points to represent a meaningful elevation profile.

The default value is 50 meters, which will return 20 sample points for each kilometer.