Report non-fatal collection errors in the exporter metric. (#1439)

As per prometheus/client_golang#543, pass the Registry for exporter
metrics when setting up the /metrics HTTP handler.

With this, the `promhttp_metric_handler_errors_total` metric will
increment on (possibly non-fatal) collection-time errors, such as
duplicate metrics from text files.

Signed-off-by: Matthias Rampke <mr@soundcloud.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/node_exporter.go b/node_exporter.go
index 550d7b1..ceee4e1 100644
--- a/node_exporter.go
+++ b/node_exporter.go
@@ -116,6 +116,7 @@ func (h *handler) innerHandler(filters ...string) (http.Handler, error) {
                         ErrorLog:            log.NewErrorLogger(),
                         ErrorHandling:       promhttp.ContinueOnError,
                         MaxRequestsInFlight: h.maxRequests,
+                        Registry:            h.exporterMetricsRegistry,
                 },
         )
         if h.includeExporterMetrics {