Different "no such overload" cases

[pudovd]

I have successfully integrated Elasticsearch with Grafana Loki via CEL, but now I want to refactor within data and I can't do it because "No such overload" errors.

$ mito --version
v1.10.0

test.json - simplified response from loki api

{
	"data": {
		"result": [
			{
				"stream": {
					"cluster": "dev"
				},
				"values": [
					[
						"1712065150402844688",
						"{\"log_level\":\"info\"}"
					]
				]
			}
		],
		"resultType": "streams",
		"stats": {}
	},
	"status": "success"
}

Case 1. collate()

Looks that collate() is executed only after repacking the data.

It's work ok. collate-ok.cel - working demo code

state.data.result.as(res,
    res.map(r, r.values.map(v, zip(["timestamp", "message"], v).with({"stream": r.stream})))
    .flatten().map(r, {"message": r.message, "stream": r.stream, "timestamp": r.timestamp})
).map(r, r.collate("message"))

mito -data test.json collate-ok.cel

[
        [
                "{\"log_level\":\"info\"}"
        ]
]

It's failed. collate-fail.cel - failing demo code

state.data.result.as(res,
    res.map(r, r.values.map(v, zip(["timestamp", "message"], v).with({"stream": r.stream})))
    .flatten()
).map(r, r.collate("message"))

mito -data test.json collate-fail.cel

failed eval: ERROR: <input>:4:19: no such overload: collate
 | ).map(r, r.collate("message"))
 | ..................^

Case 2. decode_json()

Looks that decode_json() is executed only after collate() calling.

It's work ok. decodejson-ok.cel - working demo code

state.data.result.as(res,
    res.map(r, r.values.map(v, zip(["timestamp", "message"], v).with({"stream": r.stream})))
    .flatten()
)
.collate("message")
.map(m, m.decode_json())

mito -data test.json decodejson-ok.cel

[
        {
                "log_level": "info"
        }
]

It's failed. decodejson-fail.cel - failing demo code

state.data.result.as(res,
    res.map(r, r.values.map(v, zip(["timestamp", "message"], v).with({"stream": r.stream})))
    .flatten()
)
.map(r, r.message)
.map(m, m.decode_json())

mito -data test.json decodejson-fail.cel

failed eval: ERROR: <input>:6:22: no such overload
 | .map(m, m.decode_json())
 | .....................^

I have questions about cases:

1. Why do "no such overload" errors occur?
2. How to debug such cases?

test.json
collate-fail.cel.txt
collate-ok.cel.txt
decodejson-fail.cel.txt
decodejson-ok.cel.txt