Load Carmen Cloud data in Python using dltHub

Build a Carmen Cloud-to-database or-dataframe pipeline in Python using dlt with automatic Cursor support.

In this guide, we'll set up a complete Carmen Cloud data pipeline from API credentials to your first data load in just 10 minutes. You'll end up with a fully declarative Python pipeline based on dlt's REST API connector, like in the partial example code below:

Example code
@dlt.source
def carmen_cloud_source(access_token=dlt.secrets.value):
    config: RESTAPIConfig = {
        "client": {
            "base_url": "https://api.carmencloud.com/",
            "auth": {
                "type": "api_key",
                "key": "X-Api-Key",
                "value": api_key,
            },
        },
        "resources": [
            vehicle, transport
        ],
    }
    [...]
    yield from rest_api_resources(config)


def get_data() -> None:
    # Connect to destination
    pipeline = dlt.pipeline(
        pipeline_name='carmen_cloud_pipeline',
        destination='duckdb',
        dataset_name='carmen_cloud_data', 
    )
    # Load the data
    load_info = pipeline.run(carmen_cloud_source())
    print(load_info)

Why use dltHub Workspace with LLM Context to generate Python pipelines?

  • Accelerate pipeline development with AI-native context
  • Debug pipelines, validate schemas and data with the integrated Pipeline Dashboard
  • Build Python notebooks for end users of your data
  • Low maintenance thanks to Schema evolution with type inference, resilience and self documenting REST API connectors. A shallow learning curve makes the pipeline easy to extend by any team member
  • dlt is the tool of choice for Pythonic Iceberg Lakehouses, bringing mature data loading to pythonic Iceberg with or without catalogs

What you’ll do

We’ll show you how to generate a readable and easily maintainable Python script that fetches data from carmen_cloud’s API and loads it into Iceberg, DataFrames, files, or a database of your choice. Here are some of the endpoints you can load:

  • Vehicle: Retrieve vehicle information and data for specific regions
  • Transport: Access transportation network data, including rail systems (e.g., am-rail)

You will then debug the Carmen Cloud pipeline using our Pipeline Dashboard tool to ensure it is copying the data correctly, before building a Notebook to explore your data and build reports.

Setup & steps to follow

💡
Before getting started, let's make sure Cursor is set up correctly:

Now you're ready to get started!

  1. ⚙️ Set up dlt Workspace

    Install dlt with duckdb support:

    pip install dlt[workspace]

    Initialize a dlt pipeline with Carmen Cloud support.

    dlt init dlthub:carmen_cloud duckdb

    The init command will setup the necessary files and folders for the next step.

  2. 🤠 Start LLM-assisted coding

    Here’s a prompt to get you started:

    Prompt
    Please generate a REST API Source for Carmen Cloud API, as specified in @carmen_cloud-docs.yaml 
Start with endpoint(s) vehicle and transport and skip incremental loading for now. 
Place the code in carmen_cloud_pipeline.py and name the pipeline carmen_cloud_pipeline. 
If the file exists, use it as a starting point. 
Do not add or modify any other files. 
Use @dlt rest api as a tutorial. 
After adding the endpoints, allow the user to run the pipeline with python carmen_cloud_pipeline.py and await further instructions.

  3. 🔒 Set up credentials

    API key authentication is required and must be provided to access this service. The API key can be found on the ANPR Cloud Dashboard's 'how to use' page and should be sent with each request; missing or invalid API keys will result in 401 or 403 errors respectively.

    To get the appropriate API keys, please visit the original source at carmencloud.com. If you want to protect your environment secrets in a production environment, look into setting up credentials with dlt.

  4. 🏃‍♀️ Run the pipeline in the Python terminal in Cursor

    python carmen_cloud_pipeline.py

    If your pipeline runs correctly, you’ll see something like the following:

    Pipeline carmen_cloud load step completed in 0.26 seconds
1 load package(s) were loaded to destination duckdb and into dataset carmen_cloud_data
The duckdb destination used duckdb:/carmen_cloud.duckdb location to store data
Load package 1749667187.541553 is LOADED and contains no failed jobs

  5. 📈 Debug your pipeline and data with the Pipeline Dashboard

    Now that you have a running pipeline, you need to make sure it’s correct, so you do not introduce silent failures like misconfigured pagination or incremental loading errors. By launching the dlt Workspace Pipeline Dashboard, you can see various information about the pipeline to enable you to test it. Here you can see:

    • Pipeline overview: State, load metrics
    • Data’s schema: tables, columns, types, hints
    • You can query the data itself
    dlt pipeline carmen_cloud_pipeline show

  6. 🐍 Build a Notebook with data explorations and reports

    With the pipeline and data partially validated, you can continue with custom data explorations and reports. To get started, paste the snippet below into a new marimo Notebook and ask your LLM to go from there. Jupyter Notebooks and regular Python scripts are supported as well.

    import dlt

data = dlt.pipeline("carmen_cloud_pipeline").dataset()
# get vehicle table as Pandas frame
data.vehicle.df().head()

Extra resources:

Next steps