Release v1.0.9 - DB Management Improvement

Author: app-generator

.env

@@ -5,10 +5,21 @@ DEBUG=True
 FLASK_APP=run.py
 FLASK_ENV=development
 
+# If not provided, a random one is generated 
+# SECRET_KEY=<YOUR_SUPER_KEY_HERE>
+
 # Used for CDN (in production)
 # No Slash at the end
 ASSETS_ROOT=/static/assets
 
-# LOCAL 5001 FLask
+# If DB credentials (if NOT provided, or wrong values SQLite is used) 
+# DB_ENGINE=mysql
+# DB_HOST=localhost
+# DB_NAME=appseed_db
+# DB_USERNAME=appseed_db_usr
+# DB_PASS=pass
+# DB_PORT=3306
+
+# LOCAL 5001 Flask
 # GITHUB_ID = <YOUR_GITHUB_ID>
 # GITHUB_SECRET = <YOUR_GITHUB_SECRET>

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Change Log
 
+## [1.0.9] 2022-12-31
+### Changes
+
+- `DB Management` Improvement
+  - `Silent fallback` to **SQLite**
+
 ## [1.0.8] 2022-09-07
 ### Improvements
 

apps/__init__.py

@@ -28,7 +28,18 @@ def configure_database(app):
 
     @app.before_first_request
     def initialize_database():
-        db.create_all()
+        try:
+            db.create_all()
+        except Exception as e:
+
+            print('> Error: DBMS Exception: ' + str(e) )
+
+            # fallback to SQLite
+            basedir = os.path.abspath(os.path.dirname(__file__))
+            app.config['SQLALCHEMY_DATABASE_URI'] = SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'db.sqlite3')
+
+            print('> Fallback to SQLite ')
+            db.create_all()
 
     @app.teardown_request
     def shutdown_session(exception=None):

apps/config.py

@@ -3,32 +3,68 @@
 Copyright (c) 2019 - present AppSeed.us
 """
 
-import os
+import os, random, string
 
 class Config(object):
 
     basedir = os.path.abspath(os.path.dirname(__file__))
 
-    # Set up the App SECRET_KEY
-    # SECRET_KEY = config('SECRET_KEY'  , default='S#perS3crEt_007')
-    SECRET_KEY = os.getenv('SECRET_KEY', 'S#perS3crEt_007')
-
-    # This will create a file in <app> FOLDER
-    SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'db.sqlite3')
-    SQLALCHEMY_TRACK_MODIFICATIONS = False 
-
     # Assets Management
-    ASSETS_ROOT = os.getenv('ASSETS_ROOT', '/static/assets')    
+    ASSETS_ROOT = os.getenv('ASSETS_ROOT', '/static/assets')  
 
+    # Set up the App SECRET_KEY
+    SECRET_KEY  = os.getenv('SECRET_KEY', None)
+    if not SECRET_KEY:
+        SECRET_KEY = ''.join(random.choice( string.ascii_lowercase  ) for i in range( 32 ))
+
+    # Social AUTH context
     SOCIAL_AUTH_GITHUB  = False
 
-    GITHUB_ID      = os.getenv('GITHUB_ID')
-    GITHUB_SECRET  = os.getenv('GITHUB_SECRET')
+    GITHUB_ID      = os.getenv('GITHUB_ID'    , None)
+    GITHUB_SECRET  = os.getenv('GITHUB_SECRET', None)
 
     # Enable/Disable Github Social Login    
     if GITHUB_ID and GITHUB_SECRET:
-         SOCIAL_AUTH_GITHUB  = True
-             
+         SOCIAL_AUTH_GITHUB  = True        
+
+    SQLALCHEMY_TRACK_MODIFICATIONS = False
+
+    DB_ENGINE   = os.getenv('DB_ENGINE'   , None)
+    DB_USERNAME = os.getenv('DB_USERNAME' , None)
+    DB_PASS     = os.getenv('DB_PASS'     , None)
+    DB_HOST     = os.getenv('DB_HOST'     , None)
+    DB_PORT     = os.getenv('DB_PORT'     , None)
+    DB_NAME     = os.getenv('DB_NAME'     , None)
+
+    USE_SQLITE  = True 
+
+    # try to set up a Relational DBMS
+    if DB_ENGINE and DB_NAME and DB_USERNAME:
+
+        try:
+            
+            # Relational DBMS: PSQL, MySql
+            SQLALCHEMY_DATABASE_URI = '{}://{}:{}@{}:{}/{}'.format(
+                DB_ENGINE,
+                DB_USERNAME,
+                DB_PASS,
+                DB_HOST,
+                DB_PORT,
+                DB_NAME
+            ) 
+
+            USE_SQLITE  = False
+
+        except Exception as e:
+
+            print('> Error: DBMS Exception: ' + str(e) )
+            print('> Fallback to SQLite ')    
+
+    if USE_SQLITE:
+
+        # This will create a file in <app> FOLDER
+        SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'db.sqlite3')
+    
 class ProductionConfig(Config):
     DEBUG = False
 
@@ -37,21 +73,9 @@ class ProductionConfig(Config):
     REMEMBER_COOKIE_HTTPONLY = True
     REMEMBER_COOKIE_DURATION = 3600
 
-    # PostgreSQL database
-    SQLALCHEMY_DATABASE_URI = '{}://{}:{}@{}:{}/{}'.format(
-        os.getenv('DB_ENGINE'   , 'mysql'),
-        os.getenv('DB_USERNAME' , 'appseed_db_usr'),
-        os.getenv('DB_PASS'     , 'pass'),
-        os.getenv('DB_HOST'     , 'localhost'),
-        os.getenv('DB_PORT'     , 3306),
-        os.getenv('DB_NAME'     , 'appseed_db')
-    )
-
-
 class DebugConfig(Config):
     DEBUG = True
 
-
 # Load all possible configurations
 config_dict = {
     'Production': ProductionConfig,

env.sample

@@ -1,21 +1,23 @@
-# True for development, False for production
+# True in development, False in production
 DEBUG=True
 
-# Flask ENV
 FLASK_APP=run.py
-SECRET_KEY=YOUR_SUPER_KEY
+FLASK_ENV=development
 
-# Used for CDN (in production)
-# No Slash at the end
-ASSETS_ROOT=/static/assets
+# If not provided, a random one is generated 
+# SECRET_KEY=<YOUR_SUPER_KEY_HERE>
 
-# If DEBUG=False (production mode)
+# If DB credentials (if NOT provided, or wrong values SQLite is used) 
 # DB_ENGINE=mysql
-# DB_NAME=appseed_db
 # DB_HOST=localhost
-# DB_PORT=3306
+# DB_NAME=appseed_db
 # DB_USERNAME=appseed_db_usr
-# DB_PASS=<STRONG_PASS>
+# DB_PASS=pass
+# DB_PORT=3306
+
+# Used for CDN (in production)
+# No Slash at the end
+ASSETS_ROOT=/static/assets
 
 # SOCIAL AUTH Github
 # GITHUB_ID=YOUR_GITHUB_ID

requirements.txt

@@ -16,3 +16,4 @@ blinker==1.4
 pyOpenSSL
 
 # flask_mysqldb
+# psycopg2-binary