Process "array_element" only accepts numbers for "label" parameter

[christophfriedrich]

Trying to run a process graph that contains

"reducer": {
    "process_graph": {
        "red": {
            "process_id": "array_element",
            "arguments": {
                "data": {
                    "from_parameter": "data"
                },
                "label": "B04"
            }
        },
        "nir": {
            "process_id": "array_element",
            "arguments": {
                "data": {
                    "from_parameter": "data"
                },
                "label": "B08"
            }
        },

I receive an error:

Expecting numeric value for 'label' but got 'B08'

But according to the /processes endpoint, both strings and numbers are valid:

Or as rendered in the Hub:

[soxofaan]

Indeed this is a known issue
the geopyspark driver only supports (int) index in array_element

(internal ref: EP-3583)

[jdries]

Suggested solution:
we already have a 'context' map in OpenEOProcessScriptBuilder
This map could contain a mapping from dimension names to labels along that dimension.
So {'bands':['B02','B03']}
Band name aliases may need to be mapped to a standardized name beforehand?

[clausmichele]

I really hope this will be fixed soon, since it affects the client too Open-EO/openeo-python-client#217

[jdries]

fixed on dev, will appear on prod soon.
Only for bands dimension, so no 'generic' support for labeled arrays.