Prevent overwriting Authorization with basic auth

[zgy730]

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• New tests have been added (for feature additions)

[aviau]

Looks good, thanks!

[fetzerch]

@aviau Is there a chance that you publish a new patch release to PyPI with this included any time soon?

The patch enables the connection to InfluxDB v2 via:

client = influxdb.InfluxDBClient(
        database="xyz",
        headers={
            "Authorization": "Token <base64 encoded token>"
        },
    )

This seems to be the only way of running existing scripts (that use InfluxQL queries) against the v1 compatibility API of InfluxDB v2. Unfortunately I do still have some scripts which I can't migrate to Flux because that's still missing some features.

[SGStino]

ran into this issue, turns out that username='root', password='root' makes it overwrite the Authorization header

using this fixes it:

client = influxdb.DataFrameClient(host='<hostname>', username=None, password=None, headers={'Authorization':'Token <token_without_extra_encoding>'})

In version 5.3.1 from pip (which, by the way, doesn't have a tag in this repo yet?)