The first section,
["POST URL", "METHOD"], defines the header row. The rest
of the query from the JSON data (in this case, a HAR file) is appended after
the header row.
The deconstruction into a row of data happens at this section:
This should match the order and size of the header row to get a proper CSV file.
The final selection,
@csv is a special jq command that converts the list of
arrays into a CSV format. The results are output to the terminal, but can
be redirected to a file via stdout redirection.
jq -r '["POST URL", "METHOD"], (.log.entries.request | select( .method == "GET" ) | [.url, .method]) | @csv' website.har