config refactor (#1854)

* split out config

* add tests for base and app config, refactor client config out of app config

* refactor default config retrieval

* create config test class and helper functions

* move default_config into server to fix import issue

server/test/unit/cli/test_launch.py

@@ -0,0 +1,28 @@
+import filecmp
+import os
+import shutil
+import unittest
+
+import yaml
+
+from server.default_config import default_config
+from server.test import FIXTURES_ROOT
+
+
+class CLIPLaunchTests(unittest.TestCase):
+    tmp_dir = os.path.join(FIXTURES_ROOT, "dump_configs")
+
+    @classmethod
+    def setUpClass(cls) -> None:
+        os.mkdir(cls.tmp_dir)
+
+    @classmethod
+    def tearDownClass(cls) -> None:
+        shutil.rmtree(cls.tmp_dir)
+
+
+def test_dump_default_config(self):
+    os.system(f"cellxgene launch --dump-default-config > {self.tmp_dir}/test_config_dump.txt")
+    with open(f"{self.tmp_dir}/expected_config_dump.txt", "w") as expected_config:
+        expected_config.write(yaml.dump(default_config))
+    filecmp.cmp(f"{self.tmp_dir}/expected_config_dump.txt", f"{self.tmp_dir}/test_config_dump.txt")