# Open Masterdata

If your wholesaler publishes article master data through **Open Masterdata
(OMD)** — the REST standard of the German building-services trade, successor
of DATANORM — Mercura keeps the articles you carry current from that service:
names and texts, prices, units, ETIM features, successors, alternatives and
accessories. Like the other chapters under *Ready-made connections*, this is
not an endpoint of the Mercura API: Mercura calls your wholesaler, not the
other way round.
An OMD service answers one article at a time and has no "what changed"
endpoint. The trigger is therefore a **delta file**: a JSON list of changed
articles that your wholesaler or your own system places in the folder
`omd_delta/` of your Mercura SFTP mailbox. Every file starts one run.
Admins of your organisation set it up in Mercura: on
**Settings → Integrations**, the **Open Masterdata** tile under *Add an
integration* → **Set up** opens **Settings → Integrations → For developers →
Data from your system**. There, click **Set up Open Masterdata** — or, once
another data source exists, **Add resource → Open Masterdata** on the
**Resources** tab. Afterwards it is a row in that resources table. The SFTP
mailbox is enabled under **Settings → Integrations → SFTP**.

 - [What you need from your wholesaler](https://docs.mercura.ai/openapi/open-masterdata/what-you-need-from-your-wholesaler.md): ## What you need from your wholesaler | What | Example | Notes | | --- | --- | --- | | Service address | `https://omd.wholesaler.example/openmasterdata/v1.1.0` | Up to and including the version segme
 - [Settings](https://docs.mercura.ai/openapi/open-masterdata/settings.md): ## Settings - **Package format.** OMD 1.1.0 and older expect the requested data packages joined (`datapackage=basic|prices`), 1.2.0 and newer one parameter per package. A wrong format is silent: the s
 - [The delta file](https://docs.mercura.ai/openapi/open-masterdata/the-delta-file.md): ## The delta file Place one JSON file per batch of changes in `omd_delta/`. An empty list is valid. ```json { "products": [ { "change": "new", "manufacturerID": "40526", "manufacturerIDType"
 - [Runs and troubleshooting](https://docs.mercura.ai/openapi/open-masterdata/runs-and-troubleshooting.md): ## Runs and troubleshooting The **Runs** tab of the Open Masterdata resource lists the last delta files with their counts — changes, fetched, not found, collective articles skipped, failed — and **Set