Merge pull request #76 from geoadmin/feat-PB-1897-resolve-cyclic-import

PB-1897: Resolve cyclic import

Author: msom

.pylintrc

@@ -64,10 +64,7 @@ disable=missing-docstring,
     missing-module-docstring,
     useless-object-inheritance,
     unnecessary-lambda-assignment,
-    too-many-positional-arguments,
-    # there is currently a bug preventing disabling cyclic imports on a specific line
-    # see https://github.com/pylint-dev/pylint/issues/9490
-    cyclic-import
+    too-many-positional-arguments
 
 # Enable the message, report, category or checker with the given id(s). You can
 # either give multiple identifier separated by comma (,) or put this option

app/__init__.py

@@ -1,123 +1,2 @@
-import gzip
-import logging
-import time
-
-from flask_caching import Cache
-from werkzeug.exceptions import HTTPException
-
-from flask import Flask
-from flask import g
-from flask import request
-
-from app import settings
-from app.helpers.utils import make_error_msg
-
-logger = logging.getLogger(__name__)
-route_logger = logging.getLogger('app.routes')
-
-# Standard Flask application initialisation
-
-app = Flask(__name__)
-app.config.from_object(settings)
-
-cache = Cache(app)
-
-
-# NOTE it is better to have this method registered first (before validate_origin) otherwise
-# the route might not be logged if another method reject the request.
-@app.before_request
-def log_route():
-    g.setdefault('request_started', time.time())
-    route_logger.debug('%s %s', request.method, request.path)
-
-
-# Add CORS Headers to all request
-@app.after_request
-def add_cors_header(response):
-    # Do not add CORS header to internal /checker endpoint.
-    if request.endpoint == 'checker':
-        return response
-
-    response.headers['Access-Control-Allow-Methods'] = 'GET, HEAD, OPTIONS'
-    response.headers['Access-Control-Allow-Headers'] = '*'
-    response.headers['Access-Control-Allow-Origin'] = "*"
-    return response
-
-
-# Add Cache-Control Headers to all request except for checker
-@app.after_request
-def add_cache_control_header(response):
-    # Do not add Cache-Control header to internal /checker endpoint.
-    if request.endpoint == 'checker':
-        return response
-
-    # no cache on these 5xx errors, they are supposed to be temporary
-    if response.status_code in (502, 503, 504, 507):
-        response.headers['Cache-Control'] = 'no-cache'
-    # short cache duration for other 5xx errors
-    elif response.status_code >= 500:
-        response.headers['Cache-Control'] = 'public, max-age=10'
-    else:
-        response.headers['Cache-Control'] = settings.CACHE_CONTROL_HEADER
-    return response
-
-
-@app.after_request
-def compress(response):
-    accept_encoding = request.headers.get('accept-encoding', '').lower()
-
-    if (
-        response.status_code < 200 or response.status_code >= 300 or response.direct_passthrough or
-        'gzip' not in accept_encoding or 'Content-Encoding' in response.headers
-    ):
-        return response
-
-    content = gzip.compress(response.get_data(), compresslevel=settings.GZIP_COMPRESSION_LEVEL)
-    response.set_data(content)
-    response.headers['content-length'] = len(content)
-    response.headers['content-encoding'] = 'gzip'
-    return response
-
-
-# NOTE it is better to have this method registered last (after add_cors_header) otherwise
-# the response might not be correct (e.g. headers added in another after_request hook).
-@app.after_request
-def log_response(response):
-    log_extra = {
-        'response': {
-            "status_code": response.status_code,
-            "headers": dict(response.headers.items()),
-        },
-        "duration": time.time() - g.get('request_started', time.time())
-    }
-    if route_logger.isEnabledFor(logging.DEBUG):
-        log_extra['response']['json'] = response.json if response.is_json else response.data
-    route_logger.info("%s %s - %s", request.method, request.path, response.status, extra=log_extra)
-    return response
-
-
-# Register error handler to make sure that every error returns a json answer
-@app.errorhandler(Exception)
-def handle_exception(err):
-    """Return JSON instead of HTML for HTTP errors."""
-    if isinstance(err, HTTPException):
-        if err.code >= 500:
-            logger.exception(err)
-        else:
-            logger.error(err)
-        return make_error_msg(err.code, err.description)
-
-    logger.exception('Unexpected exception: %s', err)
-    return make_error_msg(500, "Internal server error, please consult logs")
-
-
-@app.teardown_appcontext
-def close_db_connection(exception):
-    if exception:
-        logger.exception('Unexpected exception: %s', exception)
-    # close db connection
-    if hasattr(g, 'db_connection'):
-        g.db_connection.close()
-
-
-from app import routes  # isort:skip pylint: disable=wrong-import-position
+from app import routes
+from app.app import app

app/app.py

@@ -0,0 +1,120 @@
+import gzip
+import logging
+import time
+
+from flask_caching import Cache
+from werkzeug.exceptions import HTTPException
+
+from flask import Flask
+from flask import g
+from flask import request
+
+from app import settings
+from app.helpers.utils import make_error_msg
+
+logger = logging.getLogger(__name__)
+route_logger = logging.getLogger('app.routes')
+
+# Standard Flask application initialisation
+
+app = Flask(__name__)
+app.config.from_object(settings)
+
+cache = Cache(app)
+
+
+# NOTE it is better to have this method registered first (before validate_origin) otherwise
+# the route might not be logged if another method reject the request.
+@app.before_request
+def log_route():
+    g.setdefault('request_started', time.time())
+    route_logger.debug('%s %s', request.method, request.path)
+
+
+# Add CORS Headers to all request
+@app.after_request
+def add_cors_header(response):
+    # Do not add CORS header to internal /checker endpoint.
+    if request.endpoint == 'checker':
+        return response
+
+    response.headers['Access-Control-Allow-Methods'] = 'GET, HEAD, OPTIONS'
+    response.headers['Access-Control-Allow-Headers'] = '*'
+    response.headers['Access-Control-Allow-Origin'] = "*"
+    return response
+
+
+# Add Cache-Control Headers to all request except for checker
+@app.after_request
+def add_cache_control_header(response):
+    # Do not add Cache-Control header to internal /checker endpoint.
+    if request.endpoint == 'checker':
+        return response
+
+    # no cache on these 5xx errors, they are supposed to be temporary
+    if response.status_code in (502, 503, 504, 507):
+        response.headers['Cache-Control'] = 'no-cache'
+    # short cache duration for other 5xx errors
+    elif response.status_code >= 500:
+        response.headers['Cache-Control'] = 'public, max-age=10'
+    else:
+        response.headers['Cache-Control'] = settings.CACHE_CONTROL_HEADER
+    return response
+
+
+@app.after_request
+def compress(response):
+    accept_encoding = request.headers.get('accept-encoding', '').lower()
+
+    if (
+        response.status_code < 200 or response.status_code >= 300 or response.direct_passthrough or
+        'gzip' not in accept_encoding or 'Content-Encoding' in response.headers
+    ):
+        return response
+
+    content = gzip.compress(response.get_data(), compresslevel=settings.GZIP_COMPRESSION_LEVEL)
+    response.set_data(content)
+    response.headers['content-length'] = len(content)
+    response.headers['content-encoding'] = 'gzip'
+    return response
+
+
+# NOTE it is better to have this method registered last (after add_cors_header) otherwise
+# the response might not be correct (e.g. headers added in another after_request hook).
+@app.after_request
+def log_response(response):
+    log_extra = {
+        'response': {
+            "status_code": response.status_code,
+            "headers": dict(response.headers.items()),
+        },
+        "duration": time.time() - g.get('request_started', time.time())
+    }
+    if route_logger.isEnabledFor(logging.DEBUG):
+        log_extra['response']['json'] = response.json if response.is_json else response.data
+    route_logger.info("%s %s - %s", request.method, request.path, response.status, extra=log_extra)
+    return response
+
+
+# Register error handler to make sure that every error returns a json answer
+@app.errorhandler(Exception)
+def handle_exception(err):
+    """Return JSON instead of HTML for HTTP errors."""
+    if isinstance(err, HTTPException):
+        if err.code >= 500:
+            logger.exception(err)
+        else:
+            logger.error(err)
+        return make_error_msg(err.code, err.description)
+
+    logger.exception('Unexpected exception: %s', err)
+    return make_error_msg(500, "Internal server error, please consult logs")
+
+
+@app.teardown_appcontext
+def close_db_connection(exception):
+    if exception:
+        logger.exception('Unexpected exception: %s', exception)
+    # close db connection
+    if hasattr(g, 'db_connection'):
+        g.db_connection.close()

app/helpers/db.py

@@ -4,8 +4,8 @@
 
 from flask import g
 
-from app import cache
 from app import settings
+from app.app import cache
 
 logger = logging.getLogger(__name__)
 

app/helpers/helpers_search.py

@@ -14,7 +14,7 @@
 from shapely.wkt import dumps as shape_dumps
 from shapely.wkt import loads as shape_loads
 
-from app import cache
+from app.app import cache
 from app.lib import sphinxapi
 
 logger = logging.getLogger(__name__)

app/routes.py

@@ -5,7 +5,7 @@
 from flask import make_response
 from flask import request
 
-from app import app
+from app.app import app
 from app.lib import sphinxapi
 from app.search import Search
 from app.settings import SEARCH_SPHINX_HOST

service_launcher.py

@@ -1,6 +1,6 @@
 '''Service launcher to use Flask without wsgi.py
 '''
-from app import app  # pylint: disable=unused-import
+from app.app import app  # pylint: disable=unused-import
 from app.helpers.utils import init_logging
 
 # Initialize Logging using JSON format for all loggers and using the Stream Handler.

tests/unit_tests/base_test.py

@@ -2,7 +2,7 @@
 
 from gatilegrid import getTileGrid
 
-from app import app
+from app.app import app
 from app.helpers.helpers_search import parse_box2d
 from app.helpers.validation_search import SUPPORTED_OUTPUT_SRS
 from app.settings import CACHE_CONTROL_HEADER

wsgi.py

@@ -2,7 +2,7 @@
 
 from gunicorn.app.base import BaseApplication
 
-from app import app as application
+from app.app import app as application
 from app.helpers.utils import get_logging_cfg
 from app.settings import FORWARDED_PROTO_HEADER_NAME
 from app.settings import FORWARED_ALLOW_IPS