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Last tested: Nov 11, 2019
When creating a new connection using the create_connection(body) API you need to pass the certificate body for server authentication.
To create this string you can run in a terminal the following command line:cat yourjsonfile.json | base64
ORcat yourp12file.p12 | base64
Wrap the result in quotes and use that as the value for certificate.
For BigQuery
certificate (string): (Write-Only) Base64 encoded Certificate body for server authentication (when appropriate for dialect).,
file_type (string): (Write-Only) Certificate keyfile type - .json or .p12,
--> you don't give a filename to the API to upload, you have to put the content of the file into the API request as a Base64 encoded string value
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