Refactor BigQuery operators

[turbaszek]

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[olchas]

LGTM

[mik-laj]

Should we raise exception when user provide mutully exclussive parameters e.g. table_resource and source_uris?

[potiuk]

I agree. the behaviour is a bit undefined if wrong combination of parameters is specified. If table_resources is undefined and schema_fields are defined and source_objects and bucket are, I am not sure what happens here. I think all the "superfluous" combinations where same data is provided by different means should result in exception

[turbaszek]

I've added an exception

[potiuk]

Few small comments

[potiuk]

By when will it be deprecated ?

[turbaszek]

No idea, we've never discussed when we will deprecate such things

[potiuk]

I agree. the behaviour is a bit undefined if wrong combination of parameters is specified. If table_resources is undefined and schema_fields are defined and source_objects and bucket are, I am not sure what happens here. I think all the "superfluous" combinations where same data is provided by different means should result in exception