API: Add by UID routes for data sources (#29884)

- also add Get by UID+OrgID to datasource cache
- Refactor backend commands for Delete and Get to be unified

docs/sources/http_api/data_source.md

@@ -31,6 +31,7 @@ Content-Type: application/json
    {
      "id": 1,
      "orgId": 1,
+     "uid": "H8joYFVGz"
      "name": "datasource_elastic",
      "type": "elasticsearch",
      "typeLogoUrl": "public/app/plugins/datasource/elasticsearch/img/elasticsearch.svg",
@@ -74,6 +75,53 @@ Content-Type: application/json
 
 {
   "id": 1,
+  "uid": "kLtEtcRGk",
+  "orgId": 1,
+  "name": "test_datasource",
+  "type": "graphite",
+  "typeLogoUrl": "",
+  "access": "proxy",
+  "url": "http://mydatasource.com",
+  "password": "",
+  "user": "",
+  "database": "",
+  "basicAuth": false,
+  "basicAuthUser": "",
+  "basicAuthPassword": "",
+  "withCredentials": false,
+  "isDefault": false,
+  "jsonData": {
+    "graphiteType": "default",
+    "graphiteVersion": "1.1"
+  },
+  "secureJsonFields": {},
+  "version": 1,
+  "readOnly": false
+}
+```
+
+## Get a single data source by UID
+
+`GET /api/datasources/uid/:uid`
+
+**Example request:**
+
+```http
+GET /api/datasources/uid/kLtEtcRGk HTTP/1.1
+Accept: application/json
+Content-Type: application/json
+Authorization: Bearer eyJrIjoiT0tTcG1pUlY2RnVKZTFVaDFsNFZXdE9ZWmNrMkZYbk
+```
+
+**Example Response**:
+
+```http
+HTTP/1.1 200
+Content-Type: application/json
+
+{
+  "id": 1,
+  "uid": "kLtEtcRGk",
   "orgId": 1,
   "name": "test_datasource",
   "type": "graphite",
@@ -119,6 +167,7 @@ Content-Type: application/json
 
 {
   "id": 1,
+  "uid": "kLtEtcRGk",
   "orgId": 1,
   "name": "test_datasource",
   "type": "graphite",
@@ -396,6 +445,28 @@ Content-Type: application/json
 {"message":"Data source deleted"}
 ```
 
+## Delete an existing data source by UID
+
+`DELETE /api/datasources/uid/:uid`
+
+**Example request:**
+
+```http
+DELETE /api/datasources/uid/kLtEtcRGk HTTP/1.1
+Accept: application/json
+Content-Type: application/json
+Authorization: Bearer eyJrIjoiT0tTcG1pUlY2RnVKZTFVaDFsNFZXdE9ZWmNrMkZYbk
+```
+
+**Example response**:
+
+```http
+HTTP/1.1 200
+Content-Type: application/json
+
+{"message":"Data source deleted"}
+```
+
 ## Delete an existing data source by name
 
 `DELETE /api/datasources/name/:datasourceName`