Allow Celery queue settings to be defined by ENV_TOKENS

General good-practice cleanup requested by @jibsheet. Also includes some
pylint fixes myh editor flagged during this cleanup.

lms/envs/aws.py

@@ -259,15 +259,18 @@ BULK_EMAIL_DEFAULT_RETRY_DELAY = ENV_TOKENS.get('BULK_EMAIL_DEFAULT_RETRY_DELAY'
 BULK_EMAIL_MAX_RETRIES = ENV_TOKENS.get('BULK_EMAIL_MAX_RETRIES', BULK_EMAIL_MAX_RETRIES)
 BULK_EMAIL_INFINITE_RETRY_CAP = ENV_TOKENS.get('BULK_EMAIL_INFINITE_RETRY_CAP', BULK_EMAIL_INFINITE_RETRY_CAP)
 BULK_EMAIL_LOG_SENT_EMAILS = ENV_TOKENS.get('BULK_EMAIL_LOG_SENT_EMAILS', BULK_EMAIL_LOG_SENT_EMAILS)
-BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS = ENV_TOKENS.get('BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS', BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS)
+BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS = ENV_TOKENS.get(
+    'BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS',
+    BULK_EMAIL_RETRY_DELAY_BETWEEN_SENDS
+)
 # We want Bulk Email running on the high-priority queue, so we define the
 # routing key that points to it. At the moment, the name is the same.
 # We have to reset the value here, since we have changed the value of the queue name.
-BULK_EMAIL_ROUTING_KEY = HIGH_PRIORITY_QUEUE
+BULK_EMAIL_ROUTING_KEY = ENV_TOKENS.get('BULK_EMAIL_ROUTING_KEY', HIGH_PRIORITY_QUEUE)
 
 # We can run smaller jobs on the low priority queue. See note above for why
 # we have to reset the value here.
-BULK_EMAIL_ROUTING_KEY_SMALL_JOBS = LOW_PRIORITY_QUEUE
+BULK_EMAIL_ROUTING_KEY_SMALL_JOBS = ENV_TOKENS.get('BULK_EMAIL_ROUTING_KEY_SMALL_JOBS', LOW_PRIORITY_QUEUE)
 
 # following setting is for backward compatibility
 if ENV_TOKENS.get('COMPREHENSIVE_THEME_DIR', None):
@@ -352,8 +355,10 @@ if "TRACKING_IGNORE_URL_PATTERNS" in ENV_TOKENS:
 
 # SSL external authentication settings
 SSL_AUTH_EMAIL_DOMAIN = ENV_TOKENS.get("SSL_AUTH_EMAIL_DOMAIN", "MIT.EDU")
-SSL_AUTH_DN_FORMAT_STRING = ENV_TOKENS.get("SSL_AUTH_DN_FORMAT_STRING",
-                                           "/C=US/ST=Massachusetts/O=Massachusetts Institute of Technology/OU=Client CA v1/CN={0}/emailAddress={1}")
+SSL_AUTH_DN_FORMAT_STRING = ENV_TOKENS.get(
+    "SSL_AUTH_DN_FORMAT_STRING",
+    "/C=US/ST=Massachusetts/O=Massachusetts Institute of Technology/OU=Client CA v1/CN={0}/emailAddress={1}"
+)
 
 # Django CAS external authentication settings
 CAS_EXTRA_LOGIN_PARAMS = ENV_TOKENS.get("CAS_EXTRA_LOGIN_PARAMS", None)
@@ -599,7 +604,7 @@ TRACKING_SEGMENTIO_SOURCE_MAP = ENV_TOKENS.get("TRACKING_SEGMENTIO_SOURCE_MAP",
 VERIFY_STUDENT = AUTH_TOKENS.get("VERIFY_STUDENT", VERIFY_STUDENT)
 
 # Grades download
-GRADES_DOWNLOAD_ROUTING_KEY = HIGH_MEM_QUEUE
+GRADES_DOWNLOAD_ROUTING_KEY = ENV_TOKENS.get('GRADES_DOWNLOAD_ROUTING_KEY', HIGH_MEM_QUEUE)
 
 GRADES_DOWNLOAD = ENV_TOKENS.get("GRADES_DOWNLOAD", GRADES_DOWNLOAD)
 
@@ -857,7 +862,7 @@ if ENV_TOKENS.get('AUDIT_CERT_CUTOFF_DATE', None):
 
 ################################ Settings for Credentials Service ################################
 
-CREDENTIALS_GENERATION_ROUTING_KEY = HIGH_PRIORITY_QUEUE
+CREDENTIALS_GENERATION_ROUTING_KEY = ENV_TOKENS.get('CREDENTIALS_GENERATION_ROUTING_KEY', HIGH_PRIORITY_QUEUE)
 
 # The extended StudentModule history table
 if FEATURES.get('ENABLE_CSMH_EXTENDED'):