Fix collect_datasource_items when hitting special templated datasource

The machinery croaked on `"value": ["$__all"]`. This will get skipped
now, but a warning will be emitted.

Author: amotl

CHANGES.rst

@@ -5,6 +5,8 @@ grafana-wtf changelog
 
 in progress
 ===========
+- Fix ``collect_datasource_items`` when hitting special templated datasource.
+  Thanks, @mauhiz.
 
 2023-02-09 0.14.0
 =================

grafana_wtf/core.py

@@ -27,7 +27,7 @@
     DatasourceItem,
     GrafanaDataModel,
 )
-from grafana_wtf.util import JsonPathFinder, as_bool
+from grafana_wtf.util import JsonPathFinder, as_bool, to_list
 
 log = logging.getLogger(__name__)
 
@@ -499,28 +499,40 @@ def index(self):
     def collect_datasource_items(self, element):
         element = element or []
         items = []
+
+        def add(item):
+            if item is not None and item not in items:
+                items.append(item)
+
         for node in element:
-            ds = None
 
             # Directly defined datasources.
             if "datasource" in node and node["datasource"]:
                 ds = node.datasource
-                if isinstance(ds, Munch):
+                if isinstance(ds, str):
+                    add(ds)
+                elif isinstance(ds, Munch):
                     ds = dict(ds)
+                    add(ds)
+                continue
 
             # Datasources defined as variables.
             if "type" in node and node["type"] == "datasource":
-                ds_name = node.get("current", {}).get("value")
-                datasource = self.datasource_by_name.get(ds_name, {})
-                ds = dict(
-                    type=datasource.get("type"),
-                    uid=datasource.get("uid"),
-                    name=datasource.get("name"),
-                    url=datasource.get("url"),
-                )
+                values = to_list(node.get("current", {}).get("value"))
+                for ds_name in values:
+                    datasource = self.datasource_by_name.get(ds_name)
+                    if datasource is None:
+                        log.warning(f"Data source '{ds_name}' not found")
+                        continue
+                    ds = dict(
+                        type=datasource.get("type"),
+                        uid=datasource.get("uid"),
+                        name=datasource.get("name"),
+                        url=datasource.get("url"),
+                    )
+                    add(ds)
+                continue
 
-            if ds is not None and ds not in items:
-                items.append(ds)
         return items
 
     def index_dashboards(self):

grafana_wtf/util.py

@@ -165,3 +165,9 @@ def format_dict(data) -> str:
         output.write(entry)
     output.seek(0)
     return output.read().rstrip()
+
+
+def to_list(value):
+    if not isinstance(value, list):
+        value = [value]
+    return value

tests/test_core.py

@@ -0,0 +1,37 @@
+from unittest.mock import Mock
+
+from munch import Munch
+
+from grafana_wtf.core import Indexer
+
+
+def test_collect_datasource_items_variable_all():
+    """
+    Verify fix for `TypeError: unhashable type: 'list'` in `collect_datasource_items`.
+
+    https://github.com/panodata/grafana-wtf/issues/62
+    """
+    node = Munch(
+        {
+            "current": Munch({"selected": True, "text": ["All"], "value": ["$__all"]}),
+            "hide": 0,
+            "includeAll": True,
+            "multi": True,
+            "name": "datasource",
+            "options": [],
+            "query": "prometheus",
+            "queryValue": "",
+            "refresh": 1,
+            "regex": "/.*-storage$/",
+            "skipUrlSync": False,
+            "type": "datasource",
+        }
+    )
+    engine_mock = Mock(
+        scan_datasources=Mock(return_value=[]),
+        scan_dashboards=Mock(return_value=[]),
+        dashboard_details=Mock(return_value=[]),
+    )
+    indexer = Indexer(engine=engine_mock)
+    result = indexer.collect_datasource_items([node])
+    assert result == []