Clients may have platform-specific metrics they would like uploaded
(e.g. extracted from MetricKit on iOS). Add a new local API endpoint
that allows metrics to be updated by a simple name/value JSON-encoded
struct.
Signed-off-by: Mihai Parparita <mihai@tailscale.com>
The prefix is a signal to tsweb to treat this as a gauge metric when
generating the Prometheus version.
Signed-off-by: Mihai Parparita <mihai@tailscale.com>
And annotate magicsock as a start.
And add localapi and debug handlers with the Prometheus-format
exporter.
Updates #3307
Change-Id: I47c5d535fe54424741df143d052760387248f8d3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>