chore(RHTAPWATCH-592): Create README under o11y/exporters

Signed-off-by: Kousalya Lakshmanan <[email protected]>

README.md

@@ -3,6 +3,7 @@
 This repository contains the following definitions for RHTAP:
   * Prometheus alerting rules (deployed to RHOBS)
   * Grafana dashboards (deployed to AppSRE's Grafana)
+  * Availability exporters
 
 ## Alerting Rules
 
@@ -125,8 +126,24 @@ to RHOBS. If additional metrics or labels are needed, add them by following the
 described in the
 [monitoring stack documentation](https://github.com/redhat-appstudio/infra-deployments/blob/main/components/monitoring/prometheus/README.md#federation-and-remote-write)
 
+## Availability exporters
+
+In order to be able to evaluate the overall availability of the Konflux ecosystem, we
+need to be able to establish the availability of each of its components.
+
+By leveraging the existing [Konflux monitoring stack](https://gitlab.cee.redhat.com/konflux/docs/documentation/-/blob/main/o11y/monitoring/monitoring.md)
+based on Prometheus, we create Prometheus exporters that generate metrics that are
+scraped by the User Workload Monitoring Prometheus instance and remote-written to RHOBS.
+
+### Availability Exporter Example
+The o11y team provides an example availability exporter that can be used as reference,
+especially in the case in which the exporter is external to the code it's monitoring.
+
+- [Exporter code](https://github.com/redhat-appstudio/o11y/tree/main/exporters/dsexporter)
+- [Exporter and service Monitor Kubernetes Resources](https://github.com/redhat-appstudio/o11y/tree/main/config/exporters/monitoring/grafana/base)
+
+For more detailed documentation on [Availability exporters](https://gitlab.cee.redhat.com/konflux/docs/documentation/-/blob/main/o11y/monitoring/availability_exporters.md?ref_type=heads)
+
 ## Support
 
-The RHTAP o11y team maintains this repository.
-Reach out to us on our [slack channel](https://redhat-internal.slack.com/archives/C04FDFTF8EB)
-for further assistance.
+- Slack: [#forum-konflux-o11y](https://app.slack.com/client/E030G10V24F/C04FDFTF8EB)

exporters/dsexporter/README.md

@@ -0,0 +1,37 @@
+# Prometheus Exporters
+
+Prometheus exporters expose metrics from a system or an application in a format that can 
+be scraped and monitored by Prometheus. The exporter may be an integral part of the 
+component that it's monitoring (self-instrumenting), or it can generate metrics for 
+another system/component.
+
+## Availability Exporter
+
+In the context of the Konflux ecosystem, the `dsexporter` serves as an 
+[Availability Exporter](https://gitlab.cee.redhat.com/konflux/docs/documentation/-/blob/main/o11y/monitoring/availability_exporters.md),
+contributing to the evaluation of the availability of each component within the system.
+By exposing this metric, it allows for monitoring and analyzing the 
+workload and performance of the associated service.
+
+## dsexporter
+
+This `datasource exporter file (dsexporter.go)` exposes a single metric named `"konflux_up"`
+that checks if the grafana datasource `"prometheus-appstudio-ds"` is available or not. 
+This metric has two labels `"service"` and `"check"` which are constant for a given time 
+series.The exporter implements a custom Prometheus collector named `CustomCollector`,
+which implements the `prometheus.Collector` interface. The `CustomCollector` struct
+has a konfluxUp field to check the availability of grafana datasource. It implements
+the `Describe` method to provide descriptions of the metrics to Prometheus and `Collect`
+method to send the current values of the metrics to Prometheus.
+
+The `test case file (dsexporter_test.go)` tests the functionality of the different functions 
+impelemented in dsexporter.go.
+
+This code provides a simple example of how to create a custom Prometheus exporter and test its 
+functionality in Go. It is useful for monitoring the performance and behavior of the overall 
+availability of the Konflux ecosystem.
+
+The o11y team provides an example availability exporter that can be used as reference below:
+
+* [Exporter code](https://github.com/redhat-appstudio/o11y/tree/main/exporters/dsexporter)
+* [Exporter and Service Monitor Kubernetes Resources](https://github.com/redhat-appstudio/o11y/tree/main/config/exporters/monitoring/grafana/base)