Reduce transferred data (allow removing metadata)

This is a feature request from @webapperc on DBnomics forum.

Description

• As a client of the API
• I want to receive JSON responses without metadata
• in order to reduce the amount of data transferred.

This evolution has been requested by the community:

• https://forum.db.nomics.world/t/dbnomics-api-v22-released/204/8

Analysis

When loading UNDATA/DF_UNDATA_WDI/A.DT_AMT_BLAT_CD.AFG, due to gzip compression, 27.5kb are transferred for a content size of 102kb.

When keeping only the "series" first-level JSON property, the content size equals 2.1kb.

It is worth adding an query string GET parameter to control which first-level JSON properties to return.

See also:

• https://developers.google.com/web/tools/chrome-devtools/network-performance/reference#uncompressed

Proposition

Add a new metadata (boolean) query string GET parameter to ...

• /series
• /series/{provider_code}/{dataset_code}
• /series/{provider_code}/{dataset_code}/{series_code}

... working like so:

• if missing or true, return all properties (like before)
• else do not return the metadata of providers and datasets