Check connections before launching

* qc_app/__init__.py (refactor): Check connection before launching the
  application
* qc_app/check_connections.py (new file): Add code to check
  connections
* qc_app/db_utils.py (refactor): enable passing the database uri as an
  argument to the connection creation function.
* scripts/worker.py (refactor): Use new code to check for redis
  connection.

1 files changed, 5 insertions, 0 deletions

diff --git a/qc_app/__init__.py b/qc_app/__init__.py
index 6b760b9..eefe236 100644
--- a/qc_app/__init__.py
+++ b/qc_app/__init__.py
@@ -7,6 +7,7 @@ from flask import Flask
 from .entry import entrybp
 from .parse import parsebp
 from .dbinsert import dbinsertbp
+from .check_connections import check_db, check_redis
 
 def instance_path():
     """Retrieve the `instance_path`. Raise an exception if not defined."""
@@ -25,6 +26,10 @@ def create_app(instance_dir):
     app.config.from_pyfile(os.path.join(os.getcwd(), "etc/default_config.py"))
     app.config.from_pyfile("config.py") # Override defaults with instance path
 
+    # Check the connection
+    check_db(app.config["SQL_URI"])
+    check_redis(app.config["REDIS_URL"])
+
     # setup blueprints
     app.register_blueprint(entrybp, url_prefix="/")
     app.register_blueprint(parsebp, url_prefix="/parse")