added unit test

cellxgene_gateway/env.py

@@ -24,21 +24,22 @@ env_vars = {
     "GATEWAY_IP": ip,
 }
 
-if not all(env_vars.values()):
-    raise ValueError(
-        f"""
-Please ensure that environment variables are set correctly.
-The ones with None below are missing and need to be set.
+def validate():
+    if not all(env_vars.values()):
+        raise ValueError(
+            f"""
+    Please ensure that environment variables are set correctly.
+    The ones with None below are missing and need to be set.
 
-{env_vars}
+    {env_vars}
 
-Set them at the terminal before running the gateway.
-An example is:
+    Set them at the terminal before running the gateway.
+    An example is:
 
-    export CELLXGENE_LOCATION=~/anaconda/envs/cellxgene-dev/bin/cellxgene
-    export CELLXGENE_DATA=../cellxgene_data
-    export GATEWAY_HOST=localhost:5005
-    export GATEWAY_PROTOCOL=http
-    export GATEWAY_IP=127.0.0.1
-"""
-    )
+        export CELLXGENE_LOCATION=~/anaconda/envs/cellxgene-dev/bin/cellxgene
+        export CELLXGENE_DATA=../cellxgene_data
+        export GATEWAY_HOST=localhost:5005
+        export GATEWAY_PROTOCOL=http
+        export GATEWAY_IP=127.0.0.1
+    """
+        )

cellxgene_gateway/extra_scripts.py

@@ -8,10 +8,11 @@
 # the specific language governing permissions and limitations under the License.
 
 from cellxgene_gateway import env
+from json import loads
 
 def get_extra_scripts():
     # can be array of script tags to inject on every page, e.g. for google analytics could be
     # ['https://www.googletagmanager.com/gtag/js?id=UA-123456-2',
     #  f"{env.gateway_protocol}://{env.gateway_host}/static/js/google_ua.js"]
     # where google_ua.js is a script you add to the static/js folder prior to deployment.
-    return [] if env.extra_scripts is None else [p.strip() for p in env.extra_scripts.split(",") if len(p.strip()) > 0]
+    return [] if env.extra_scripts is None else loads(env.extra_scripts)

cellxgene_gateway/gateway.py

@@ -184,6 +184,7 @@ def do_GET(path):
 
 
 def main():
+    env.validate()
     background_thread = Thread(target=PruneProcessCache(cache))
     background_thread.start()