Update KrakenD readme with the one used in PubPlatform (#21801)

* Update KrakenD readme with the one used in PubPlatform

* Remove the images folder

Author: AAraKKe

krakend/README.md

@@ -2,61 +2,148 @@
 
 ## Overview
 
-This check monitors [KrakenD][1] through the Datadog Agent. 
+This check monitors [KrakenD][1] through the Datadog Agent.
 
-Include a high level overview of what this integration does:
-- What does your product do (in 1-2 sentences)?
-- What value will customers get from this integration, and why is it valuable to them?
-- What specific data will your integration monitor, and what's the value of that data?
+KrakenD is a high-performance API Gateway that provides a single entry point for microservices. This integration collects metrics using KrakenD's [OpenTelemetry exporter with Prometheus format][2] and supports [log collection][3] for comprehensive monitoring.
 
-**Minimum Agent version:** 7.69.0
+### What This Integration Monitors
+
+The integration collects metrics across multiple [layers][4] of the KrakenD gateway:
+
+- **HTTP Server Layer**: Request durations, response sizes, and status codes for client-facing traffic
+- **Proxy Layer**: Processing times and performance metrics for KrakenD's internal proxy operations
+- **Backend Layer**: Connection times, response durations, error rates, DNS resolution, TLS handshakes, timeouts, and connection details for upstream service calls
+- **Go Runtime**: Garbage collection, memory usage, goroutines, and Go-specific performance metrics
+- **System Process**: CPU usage, memory consumption, file descriptors, and network I/O
+
+In addition to metrics, you can collect access and application logs from KrakenD.
+
+### Deployment Support
+
+This integration works with KrakenD in both containerized (Docker, Kubernetes) and traditional deployment environments.
 
-## Setup
 
-Follow the instructions below to install and configure this check for an Agent running on a host. For containerized environments, see the [Autodiscovery Integration Templates][3] for guidance on applying these instructions.
+## Setup
 
 ### Installation
 
-The KrakenD check is included in the [Datadog Agent][2] package.
-No additional installation is needed on your server.
+The KrakenD check is included in the [Datadog Agent][6] package. No additional installation is needed on your server.
 
 ### Configuration
 
-1. Edit the `krakend.d/conf.yaml` file, in the `conf.d/` folder at the root of your Agent's configuration directory to start collecting your krakend performance data. See the [sample krakend.d/conf.yaml][4] for all available configuration options.
-
-2. [Restart the Agent][5].
+### Metrics
 
+The KrakenD integration uses the OpenTelemetry component in KrakenD with a Prometheus exporter to parse and emit metrics to Datadog. Make sure that your KrakenD installation is configured appropriately following the [instructions provided by KrakenD][7] and use the `prometheus` exporter.
+
+The snippet below configures KrakenD to emit metrics for [all layers][4] including Go and process metrics, exposing the Prometheus metrics endpoint on port 9090 on all network interfaces (`0.0.0.0`). The specific endpoint URL you configure in the integration as the `openmetrics_endpoint` option depends on your deployment:
+
+- **Same host**: `http://localhost:9090/metrics`
+- **Docker containers and Kubernetes**: With Autodiscovery you can use the template variable `%%host%%`: `http://%%host%%:9090/metrics`.
+
+```json
+{
+   "extra_config": {
+      "telemetry/opentelemetry": {
+         "service_name": "krakend-gateway",
+         "service_version": "1.0.0",
+         "exporters": {
+               "prometheus": [
+                  {
+                     "name": "krakend_metrics",
+                     "port": 9090,
+                     "listen_ip": "0.0.0.0",
+                     "process_metrics": true,
+                     "go_metrics": true
+                  }
+               ]
+         },
+         "layers": {
+               "global": {
+                  "disable_metrics": false
+               },
+               "proxy": {
+                  "disable_metrics": false
+               },
+               "backend": {
+                  "metrics": {
+                     "disable_stage": false,
+                     "round_trip": true,
+                     "read_payload": true,
+                     "detailed_connection": true,
+                     "static_attributes": [
+                           {
+                              "key": "backend_type",
+                              "value": "test_api"
+                           }
+                     ]
+                  }
+               }
+         }
+      }
+   }
+}
+```
+
+In KrakenD, emitting Go and process metrics is optional and can be disabled by setting `go_metrics` and `process_metrics` to `false`. For debugging purposes, to emit these metrics but not send them to Datadog, you can set the same options to `false` in the integration configuration. By default, they are enabled to respect the configuration set up in KrakenD.
+
+To configure the integration with KrakenD deployed on a host:
+
+1. Edit the `krakend.d/conf.yaml` file, in the `conf.d/` folder at the root of your Agent's configuration directory to start collecting your KrakenD performance data. See the sample [`krakend.d/conf.yaml`][9] for all available configuration options.
+
+2. [Restart the Agent][10].
+
+For containerized environments, see the [Autodiscovery Integration Templates][5] for guidance.
+
+### Logs
+
+Ensure the agent is configured to load logs following the instructions about [Log Collection and Integrations][3].
+
+To enable collection of KrakenD access and application logs, uncomment this section in the integration configuration file, replacing `<SERVICE>`  with the service to associate the logs with:
+
+```yaml
+logs:
+  - type: docker
+    source: krakend
+    service: <SERVICE>
+```
+
+Alternatively, in containerized environments, you can use Autodiscovery (for example, see [Docker][11] or [Kubernetes][12]) to add the logs configuration through annotations to the container or node where KrakenD is running.
 ### Validation
 
-[Run the Agent's status subcommand][6] and look for `krakend` under the Checks section.
+[Run the Agent's status subcommand][13] and look for `krakend` under the Checks section.
 
 ## Data Collected
 
 ### Metrics
 
-See [metadata.csv][7] for a list of metrics provided by this integration.
+See [metadata.csv][14] for a list of metrics provided by this integration.
 
 ### Events
 
 The KrakenD integration does not include any events.
 
 ### Service Checks
 
-The KrakenD integration does not include any service checks.
-
-See [service_checks.json][8] for a list of service checks provided by this integration.
+See [service_checks.json][15] for a list of service checks provided by this integration.
 
 ## Troubleshooting
 
-Need help? Contact [Datadog support][9].
-
-
-[1]: **LINK_TO_INTEGRATION_SITE**
-[2]: https://app.datadoghq.com/account/settings/agent/latest
-[3]: https://docs.datadoghq.com/agent/kubernetes/integrations/
-[4]: https://github.com/DataDog/integrations-core/blob/master/krakend/datadog_checks/krakend/data/conf.yaml.example
-[5]: https://docs.datadoghq.com/agent/guide/agent-commands/#start-stop-and-restart-the-agent
-[6]: https://docs.datadoghq.com/agent/guide/agent-commands/#agent-status-and-information
-[7]: https://github.com/DataDog/integrations-core/blob/master/krakend/metadata.csv
-[8]: https://github.com/DataDog/integrations-core/blob/master/krakend/assets/service_checks.json
-[9]: https://docs.datadoghq.com/help/
+Need help? Contact [Datadog support][16].
+
+
+[1]: https://www.krakend.io/
+[2]: https://www.krakend.io/docs/telemetry/prometheus/
+[3]: https://docs.datadoghq.com/logs/log_collection/
+[4]: https://www.krakend.io/docs/telemetry/opentelemetry-layers-metrics/
+[5]: https://docs.datadoghq.com/agent/kubernetes/integrations/
+[6]: https://app.datadoghq.com/account/settings/agent/latest
+[7]: https://www.krakend.io/docs/telemetry/opentelemetry/
+[8]: https://www.krakend.io/docs/telemetry/opentelemetry-layers-metrics/
+[9]: https://github.com/DataDog/integrations-core/blob/master/krakend/datadog_checks/krakend/data/conf.yaml.example
+[10]: https://docs.datadoghq.com/agent/guide/agent-commands/#start-stop-and-restart-the-agent
+[11]: https://docs.datadoghq.com/containers/docker/log
+[12]: https://docs.datadoghq.com/containers/kubernetes/log/
+[13]: https://docs.datadoghq.com/agent/guide/agent-commands/#agent-status-and-information
+[14]: https://github.com/DataDog/integrations-core/blob/master/krakend/metadata.csv
+[15]: https://github.com/DataDog/integrations-core/blob/master/krakend/assets/service_checks.json
+[16]: https://docs.datadoghq.com/help/