Editing

This section explains how to configure the edit function in c2cgeoportal.

Just like most administrative tasks, setting up editing in a c2cgeoportal application involves intervening in the database, through the c2cgeoportal administration interface.

Requirements

To be editable, a layer should satisfy the following requirements:

  1. It should be accessible with WMS, and correctly configured in the mapfile. See Mapfile configuration.

  2. Its data should be in a PostGIS table, which should be in the application database. The PostGIS table can be in a separate schema though, which is in fact recommended.

  3. The PostGIS table should include a primary key with a sequence associated. The name of the primary key attribute must be id. Example:

    db=# \d table;
                         Table "public.table"
        Column   |      Type   |                              Modifiers
    -------------+-------------+----------------------------------------------------------
     id          | integer     | not null default nextval('public.table_id_seq'::regclass)
    
  4. The PostGIS table should include one geometry column only. You will get errors if the table has multiple geometry columns.

  5. The following geometry types are fully supported: POINT, LINESTRING, POLYGON. The following geometry types are partially supported: MULTIPOINT, MULTILINESTRING, MULTIPOLYGON.

  6. If the PostGIS table has a many-to-one relationship to another table, (typically a dictionary table) there are additional requirements:

    • The name of the foreign key column should end with _id (e.g. type_id). This is not strictly required, but recommended.

    • The relationship’s target table should have at least two columns, a primary key column and a text column. By default the used text column is the column named name. The default order column is the text column. Another text column and a order column can be specified by the editingEnumerations layer metadata. Example:

{
    "type_id": {
        "value": "value_column",
        "order_by": "order_column"
    }
}

Adding or making layers editable

The application’s layers are defined in the layer table, which is managed by selecting the Layers item in the admin interface’s menu.

For a layer to be editable its geoTable field should be set. This field is the name of the PostGIS table containing the layer’s geographic data. It is a string of the form [<schemaname>.]<tablename>. If schemaname is omitted, the table is assumed to be in the public schema. The label corresponding to this field is Related Postgres table in the admin interface.

Warning

Only layers embedded in a layergroup are detected as editable.

Warning

It is recommended to limit the editing to 30 editable layers per user.

Configure layer editing

Registering edit time and user

  • To register the time of the change of an edited item, a column of type timestamp without timezone is needed in the table of the layer. In the configuration of the layer lastUpdateDateColumn has to be added in the metadata with the column name as value;

  • To register the user who edited a an item, a column of type integer is needed in the table of the layer. In the configuration of the layer lastUpdateUserColumn has to be added in the metadata with the column name as value.

Order the editable attributes in the editing panel

To put the attributes of a table in a specific order in the edit table, in the configuration of the layer editingAttributeOrder has to be added in the metadata with the list of the column names in the wanted order as value, separated by commas without blanks.

Make some attributes visible but not editable

In the configuration of the layer readonlyAttributes has to be added in the metadata with the list of the attributes which cannot be edited as value, separated by commas without blanks.

Validate geometries

If in the configuration of the layer geometryValidation is added in the the metadata and the box is checked, created geometries will be validated according to the type (point,line, polygon), for example to prevent creation of a 2-point polygon.

Configure enumeration values

The configuration of enumerations values (e.g. for drop-down list) is explained at point 6 of Requirements.

Configuring security

Editing the features of a layer implies to write changes in the database. To make sure that only authorized users may edit a feature, editable layers (including public layers) must be linked to a restriction area, used itself to specify the roles of authorized users.

The restriction area should have its readwrite field set to true in the administration interface.

Binding restriction areas and layers together can be done from the Layer objects in the admin interface. Likewise for binding from the Restriction areas.

Edit views

To be able to edit PostgreSQL views a primary key must be manually configured. Add a layer metadata geotablePrimaryKey with value the name of the column to use as primary key. That column must be of type Integer.

Example: geotablePrimaryKey: id

Enable snapping

To be able to snap while editing, the snappingConfig must be set on the layer metadata. The value is a json object containing the following optional properties:

  • edge (boolean): whether to allow snapping on edges or not;

  • vertex (boolean): whether to allow snapping on vertices or not;

  • tolerance (number): the pixel tolerance.

Managing attributes

To exclude some attributes from the editing form, list them as a comma-separated string (with no blank spaces) in the Exclude properties field of the WMS/WMTS layer forms in the admin interface.

To make some attributes readonly, add a readonlyAttributes metadata in the same form, also as a comma-separated list of attributes.