NodePit Nodes
The NodePit Nodes are part of NodePit for KNIME and turn the NodePit REST API into KNIME nodes. A workflow can search the catalog, look up a node, a workflow, or a product, and process the answer like any other table, with no request to write and no JSON to parse by hand. Use them to check which extension a workflow needs before it runs, to build an overview of the nodes of an extension, or to start a project of your own from NodePit’s data.
This page describes the current release of the nodes, which the update sites for KNIME 5.9 and later offer. The update sites for older KNIME versions offer an older release, which lacks some of the nodes and settings described here.
Finding the nodes
Open the node repository and go to NodePit → NodePit API. The nodes sit in three categories:
- Public — the nodes for the data of NodePit itself: one node for each kind of request.
- Authorize — the Basic node, which signs in with a NodePit username and password that you enter, and the Basic From Preferences node, which uses the account you entered in the NodePit preferences of KNIME.
- Advanced — the Timeouts node, which sets the network timeouts of the requests.
You can also search the node repository for the name of a node, or for the request it sends, such as “GET /api/search”.
What the nodes offer
Every node in Public sends one request to the API and returns the answer as a table. The names say what they do:
| Node | What it returns | API request |
|---|---|---|
| Search | The items that match a name, across all kinds of items | /api/search |
| Get Nodes | A list of nodes | /api/nodes |
| Get Node | One node in detail, with ports, options, and extension | /api/nodes/{nodePitId} |
| Get Node Image | The icon of a node as an image | /api/nodes/{nodePitId}/image |
| Get Categories | A list of the categories of the node repository | /api/categories |
| Get Category | One category | /api/categories/{nodePitId} |
| Get Workflows | A list of public workflows and components | /api/workflows |
| Get Workflow | One workflow, with the nodes it uses | /api/workflows/{nodePitId} |
| Get Products | A list of the products on NodePit | /api/products |
| Get Product | One product, with its latest version and extensions | /api/products/{nodePitId} |
| Get Versions | The released KNIME versions | /api/versions |
The settings of each node are the parameters of its request, such as the query of the search or the KNIME version. The REST API pages explain what they mean, and the API reference lists them all.
Connecting the nodes
The nodes pass their connection settings along a Configuration port. Every node has an input and an output for it, and the output is the input passed through, so that you can chain the nodes one after the other and keep the workflow tidy.
To sign in, put Basic From Preferences at the start of the chain, so the workflow uses the account in your NodePit preferences and contains no password. If the workflow should sign in with a different account, use the Basic node and enter its username and password. To change how long the requests may take, add the Timeouts node. Limits and Errors explains what signing in changes, which is not much for public data.
Working with the results
The result of a node is a table. For the nodes that return a list, each item is a row, and the node returns the fields that the API gives for it as columns. The dialog of a node has a Result Format setting that tells it how to turn the answer into columns, where the answer allows more than one choice.
The nodes send the same requests as any other client, so the request limits apply to them too. A workflow that looks up many items should do so one after the other and cache what it already has.
Next steps
- REST API — the requests behind the nodes, with examples
- Guides — common questions answered with the same requests, such as which extension a node needs
- NodePit for KNIME — the other parts of the extension