doc: tempo toolset, explain how to get datasource idf

Author: nherment

docs/configuration/holmesgpt/toolsets/grafanatempo.rst

@@ -24,6 +24,41 @@ You can find the Grafana URL required for Loki and Tempo in your Grafana cloud a
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+Obtaining the datasource UID
+-----------------------
+
+You may have multiple Tempo data sources setup in Grafana. HolmesGPT uses a single Tempo datasource to
+fetch the logs and it needs to know the UID of this datasource.
+
+A simple way to get the datasource UID is to access the Grafana API by running the following request:
+
+.. code-block:: bash
+    # port forward if you are using Robusta's grafana from your kubernetes cluster
+    kubectl port-forward svc/robusta-grafana 3000:80
+    # List the Tempo data sources
+    curl -s -u <username>:<password> http://localhost:3000/api/datasources | jq '.[] | select(.type == "tempo")'
+    {
+        "id": 3,
+        "uid": "klja8hsa-8a9c-4b35-1230-7baab22b02ee",
+        "orgId": 1,
+        "name": "Tempo",
+        "type": "tempo",
+        "typeName": "Tempo",
+        "typeLogoUrl": "/public/app/plugins/datasource/tempo/img/tempo_icon.svg",
+        "access": "proxy",
+        "url": "http://tempo-query-frontend.tempo:3100",
+        "user": "",
+        "database": "",
+        "basicAuth": false,
+        "isDefault": false,
+        "jsonData": {
+            "tlsSkipVerify": true
+        },
+        "readOnly": false
+    }
+    # In this case, there is a single Tempo datasourceUID
+    # with UID "klja8hsa-8a9c-4b35-1230-7baab22b02ee"
+
 Configuration
 ^^^^^^^^^^^^^