diff options
Diffstat (limited to 'vendor/github.com/prometheus/client_golang/prometheus/collector.go')
| -rw-r--r-- | vendor/github.com/prometheus/client_golang/prometheus/collector.go | 39 |
1 files changed, 25 insertions, 14 deletions
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/collector.go b/vendor/github.com/prometheus/client_golang/prometheus/collector.go index 623d3d8..3c9bae2 100644 --- a/vendor/github.com/prometheus/client_golang/prometheus/collector.go +++ b/vendor/github.com/prometheus/client_golang/prometheus/collector.go @@ -29,24 +29,35 @@ type Collector interface { // collected by this Collector to the provided channel and returns once // the last descriptor has been sent. The sent descriptors fulfill the // consistency and uniqueness requirements described in the Desc - // documentation. (It is valid if one and the same Collector sends - // duplicate descriptors. Those duplicates are simply ignored. However, - // two different Collectors must not send duplicate descriptors.) This - // method idempotently sends the same descriptors throughout the - // lifetime of the Collector. If a Collector encounters an error while - // executing this method, it must send an invalid descriptor (created - // with NewInvalidDesc) to signal the error to the registry. + // documentation. + // + // It is valid if one and the same Collector sends duplicate + // descriptors. Those duplicates are simply ignored. However, two + // different Collectors must not send duplicate descriptors. + // + // Sending no descriptor at all marks the Collector as “unchecked”, + // i.e. no checks will be performed at registration time, and the + // Collector may yield any Metric it sees fit in its Collect method. + // + // This method idempotently sends the same descriptors throughout the + // lifetime of the Collector. + // + // If a Collector encounters an error while executing this method, it + // must send an invalid descriptor (created with NewInvalidDesc) to + // signal the error to the registry. Describe(chan<- *Desc) // Collect is called by the Prometheus registry when collecting // metrics. The implementation sends each collected metric via the // provided channel and returns once the last metric has been sent. The - // descriptor of each sent metric is one of those returned by - // Describe. Returned metrics that share the same descriptor must differ - // in their variable label values. This method may be called - // concurrently and must therefore be implemented in a concurrency safe - // way. Blocking occurs at the expense of total performance of rendering - // all registered metrics. Ideally, Collector implementations support - // concurrent readers. + // descriptor of each sent metric is one of those returned by Describe + // (unless the Collector is unchecked, see above). Returned metrics that + // share the same descriptor must differ in their variable label + // values. + // + // This method may be called concurrently and must therefore be + // implemented in a concurrency safe way. Blocking occurs at the expense + // of total performance of rendering all registered metrics. Ideally, + // Collector implementations support concurrent readers. Collect(chan<- Metric) } |