# Functions
InitMetrics fills the collector variables with some Prometheus metrics and automatically registers them.
NewCounterVecWithError run promauto.NewCounterVec() catching the panic and returning an error.
NewCounterWithError run promauto.NewCounter() catching the panic and returning an error.
NewGaugeWithError run promauto.NewGauge() catching the panic and returning an error.
NewHistogramWithError run promauto.NewHistogram() catching the panic and returning an error.
SendMetrics pushes the metrics to the configured prometheus push gateway.
SendMetricsInLoop pushes the metrics in a loop until context is done.
UnregisterMetrics unregister all prometheus collectors safe in the collectors variable.
# Structs
GatewayClient is a simple wrapper over http.Client so that prometheus can do HTTP requests with the given authentication header.