The Firefly III Data Importer does not allow transaction imports by
unattended HTTP requests by default, but this can be enabled with the
`CAN_POST_FILES` environment variable. Additionally, an
`AUTO_IMPORT_SECRET` environment variable must be set containing a
shared "secret" value which must be provided in the querystring of
autoimport requests.
Since we have the Data Importer protected by Authelia, we need to make
some additional changes to the Ingress to allow unattended
authentication. Authelia supports passing the username and password of
an authorized user in the `Proxy-Authorization` HTTP request header. If
this header is valid, it will allow the request through. Unfortunately,
many HTTP clients will not set this header unless they are also
configured to explicitly connect via a forward proxy. To simplify
usage of such clients, we can configure nginx to copy the value of the
normal `Authorization` header into `Proxy-Authorization`, thus allowing
clients to use simple HTTP Basic authentication, even though the Data
Importer doesn't actually support it.
Dustin