Added a simply locust load test.

ops/tests/loadtest_search.py

+from locust import HttpUser, task, between
+from ase.data import chemical_symbols
+import random
+
+
+class QuickstartUser(HttpUser):
+    wait_time = between(1, 2)
+
+    @task
+    def empty_search(self):
+        self.client.get("/prod/rae/beta/api/repo/")
+
+    @task
+    def elements_search(self):
+        self.client.get("/prod/rae/beta/api/repo/?atoms=%s" % random.choice(chemical_symbols[1:]))
+
+    def on_start(self):
+        pass