QGIS

Accessing OS NGD data with OS NGD API - Features via QGIS

QGIS is an open GIS (Geospatial Information System) desktop application that allows you to display, interrogate, visualise and create geospatial information including from geo-centric APIs (for example, a WFS).

What you'll need

  • QGIS (version 3.12.0 or later)

Instructions

Open a blank document in QGIS. Uncheck the "Render" box for now.

Navigate to Layer → Add Layer → Add WFS Layer...

The following window will be displayed:

If you have connected to a WFS / OGC API - Features before, you will have the options available in the drop down immediately under the layers tab. If you've connected to OS NGD API – Features before, select the layer in the drop-down menu and click Connect.

If you have NOT called WFS / OGC API - Features before, click the New button below the drop-down menu.

The window that pops up requires the API information you obtained in the OS Data Hub.

Provide the service details of the API as follows:

  1. Provide a name for the API. It is good practice to name your connections in a way that makes them instantly recognisable.

  2. Input the OS NGD API – Features URL in the URL box.

  3. Your API Key that has been generated in the OS Data Hub and would have been automatically added to the URL.

  4. Click the Detect button to identify the version.

  5. As best practice we recommend that you limit your max number of features and page size to 100 to ensure a smooth service. Larger values may result in a very slow response.

You will not be required to put styling, zoom or coordinate information in the URL. This will be added at a later stage by the GIS application.

Leave all the other options blank and click OK.

It is worth noting that you will NOT require a User name or Password to use the service as all authentication is done through your OS NGD API – Features key.

Once you've completed the initial connection, the details you have supplied will be saved by your QGIS application and it can be used with any of your new or existing geospatial projects.

The next step is to select the Server connection in the drop-down list and click Connect.

You will be presented with a list of features. Click on the ones you want to apply. To select more than one feature, use the Ctrl key when choosing.

Depending on what you're attempting to do, you could either choose all layers or individual layers with features of specific interest. This can then be combined with back-drop mapping for visualisation, interrogation and analytical purposes.

It is best practice to load only the feature/s which you are interested in. In order to engage the bounding box, ensure you tick the option to Only request features overlapping the view extent. In other words, only selected features within the viewing window will load, not everything. Your viewing window in your GIS application sets your bbox.

Select the appropriate layer/s and click Add. This could take several minutes depending on which features you choose to apply.

Your data will be presented at a GB-wide scale (1:4,400,000 scale).

Please be aware that each feature, regardless of its layer, will count towards the request restriction and so the more types of features you call, the longer it will take to load into the GIS.

You can now tick the feature layer checkbox in the layers panel as well as the Render checkbox and use the data as intended. QGIS will automatically stop calling features should you need to zoom out and reposition your bounding box area of interest.

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