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For testing purpose, HTTP Basic authentication can also be used. However, it should be avoided for production applications. 

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API-key

API supports reading data using "API-key". This access mode intended to be used for custom access by a person , for example reportingfor reading ad-hoc data and/or recurring API-calls such as dashboards, PowerQuery (Excel, PoweBI), etc. It does not inteded to intended to be used for machine-to-machine communication

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• It only supports reading operations
• An API-key is valid for a single project. A user may generate multiple API-keys for accessing different project. Generating API-Key twice for the same project will result in same key.
• API-Keys belong to a single user and are confidential, thus should not be shared

Technical description

One should send API-key with each HTTP request as standard Authorization header with Reference scheme

Authorization: Reference <API-key>

Whenever possible we recommend using Reference scheme whenever possible. As a fallback, the application also accepting API-key encoded as Authorization header with Basic scheme, where username is a constant apikey and password is the API-key.

Authorization: Basic base64urlencode(apikey:<API-key>)

Note that many clients (for example Excel or browsers) will prompt users for inputting username and password if a request is sent without Authorization header and will result re-sending request with Authorization header with Basic scheme

Providing database and projectId

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