Instructions for using open interfaces in the Ryhti system
The interfaces provide you with access to the open spatial information within the built environment information system. This page contains general instructions for using the interfaces.
To use the interface services, you must have access to a geographic information system or other software that calls the interface.
The interfaces always provide you with the latest information, and you do not need to download the information in your environment.
Interface addresses
The interface addresses are available on the subpage intended for users of the Ryhti website.
The addresses are also listed in accordance with the INSPIRE classification on the Finnish Environment Institute (Syke)’s web map services page.
User licence and responsibilities
Using open interfaces is free of charge.
The use does not require an API key, but if you plan to use the interfaces in an application you develop or maintain in the long term or otherwise to use our interfaces more intensively, we require you to request a unique identifier to be used in your applications.
Also familiarise yourself with the interfaces’ terms of use before you start using the services.
Updating the information
The information provided by the interfaces is updated once a day.
Interface types – WMS or OGC?
There are two types of interfaces. Select the interface type that suits your purposes.
Combining different interfaces is often a functional solution: the data displayed on the map is retrieved from the WMS service, but more detailed queries are made to the OGC interface as needed. An example of this is highlighting the selected item on the map, in which case only the selected item is retrieved from the OGC interface.
WMS
WMS services are the best option for map visualisation as they provide better performance for both the user’s application and the map server.
In addition to map visualisation, the WMS interface enables you to call feature data for items at a certain point using GetFeatureInfo calls.
However, it is not possible to make more complex calls (e.g., based on area delineation or feature data). Additionally, calls do not return the item’s geometry, or location information. For more information on the WMS interface, see e.g., GeoServer documentation
OGC API Features
Standard OGC Api Feature interface service that returns vector data.
Select the OGC interface when visual representation of data and simple feature data queries are not sufficient. This option is suitable for situations where, for example, you want to search for items in a certain area, search for items with specific features, or get the geometry (coordinates) of the items.
Vector interfaces always have restrictions on the maximum number of objects that can be returned. This means that when using them, you must ensure that calls are divided into parts (pagination).
OGC API Features is a more modern implementation that largely corresponds to previous WFS services (OGC Web Feature Service).
Metadata descriptions
The metadata descriptions provide more detailed information on Syke’s materials and services. There are separate descriptions for open interfaces.
Disruption notices
We aim to minimise the downtime of interfaces. Any interruptions are communicated on the Ryhti website via disruption notices.
FAQs
How to get started with OGC API Features interfaces?
You can inspect the interface data by accessing its address in a browser.
E.g., https://paikkatiedot.ymparisto.fi/geoserver/ryhti_permit/ogc/features/v1
First, you will see the landing page. You can find the following information on the subpages.
- API definition: description of the service API
- Collections: a description of the collections available in the service, i.e., data sets
- Conformance: list of conformance classes
- Contact information: contact details
What software can I use to test interfaces?
You can test the interfaces with the geographic information system you use. If you do not have a geographic information system, we recommend testing with free, open source QGIS software.
You can also test OGC API Features interfaces in a browser by typing the interface address in the browser’s address bar and narrowing the search with parameters.
Why are data not available in CSV format?
The data can be retrieved directly via the interfaces. The data are updated daily, so using interfaces ensures that you always use up-to-date data.
I was only able to retrieve 3,000 construction projects via the interface. How can I get the rest?
A limit of 3,000 items has been set for items to avoid overload. You can retrieve more items by chaining your queries.
For example, the QGIS geographic information system can retrieve items in sections. If you call the interface in another way, you can use pagination to retrieve the items. Pagination is integrated in the OGC API Features standard.
If you cannot retrieve more than 3,000 items, try adding the parameter &limit=3000 after your query. This will add a link to the reply to retrieve the following page.
Example query:
https://paikkatiedot.ymparisto.fi/geoserver/ryhti_building/ogc/features/v1/collections/open_address/items?&limit=3000
I only want to retrieve the construction projects in a certain municipality via the interface. Can you do that?
You can use a filter in your geographic information system or try it directly with parameters added to the address of the OGC API Features interface. You can filter using, e.g., the municipality’s identifier or area delineation (bounding box, bbox).
Example: only buildings in Vaasa
/Items?filter=municipality_number=905&limit=3000 (you will switch to another service)
Example: area delineation
Limiting the area with a bounding box so that the area to be included is defined in accordance with the official Finnish coordinate system (ETRS TM35FIN, or EPSG:3067).
/items?bbox=490000,6904000,492000,6906000&bbox-crs=http://www.opengis.net/def/crs/EPSG/0/3067&limit=3000 (you will switch to another service)