Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/processors/starlark/testdata/compare_metrics.star

@@ -0,0 +1,26 @@
+# Example showing how to keep the last metric in order to compare it with the new one.
+#
+# Example Input:
+# cpu value=10i 1465839830100400201
+# cpu value=8i 1465839830100400301
+#
+# Example Output:
+# cpu_diff value=2i 1465839830100400301
+
+state = {
+  "last": None
+}
+
+def apply(metric):
+    # Load from the shared state the metric assigned to the key "last"
+    last = state["last"]
+    # Store the deepcopy of the new metric into the shared state and assign it to the key "last"
+    # NB: To store a metric into the shared state you have to deep copy it
+    state["last"] = deepcopy(metric)
+    if last != None:
+        # Create a new metric named "cpu_diff"
+        result = Metric("cpu_diff")
+        # Set the field "value" to the difference between the value of the last metric and the current one
+        result.fields["value"] = last.fields["value"] - metric.fields["value"]
+        result.time = metric.time
+        return result