Added the "accounting.utils.next_uri" utilities to fixed how the next URI works.

src/accounting/utils/next_url.py

@@ -0,0 +1,75 @@
+# The Mia! Accounting Flask Project.
+# Author: imacat@mail.imacat.idv.tw (imacat), 2023/2/1
+
+#  Copyright (c) 2023 imacat.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+"""The utilities to handle the next URL.
+
+This module should not import any other module from the application.
+
+"""
+from urllib.parse import urlparse, parse_qsl, ParseResult, urlencode, \
+    urlunparse
+
+from flask import request
+
+
+def append_next(uri: str) -> str:
+    """Appends the current URI as the next URI to the query argument.
+
+    :param uri: The URI.
+    :return: The URI with the current URI appended as the next URI.
+    """
+    next_uri: str = request.full_path if request.query_string else request.path
+    return __set_next(uri, next_uri)
+
+
+def inherit_next(uri: str) -> str:
+    """Inherits the current next URI to the query argument, if exists.
+
+    :param uri: The URI.
+    :return: The URI with the current next URI added at the query argument.
+    """
+    next_uri: str | None = request.form.get("next") \
+        if request.method == "POST" else request.args.get("next")
+    if next_uri is None:
+        return uri
+    return __set_next(uri, next_uri)
+
+
+def or_next(uri: str) -> str:
+    """Returns the next URI, if exists, or the supplied URI.
+
+    :param uri: The URI.
+    :return: The next URI or the supplied URI.
+    """
+    next_uri: str | None = request.form.get("next") \
+        if request.method == "POST" else request.args.get("next")
+    return uri if next_uri is None else next_uri
+
+
+def __set_next(uri: str, next_uri: str) -> str:
+    """Sets the next URI to the query arguments.
+
+    :param uri: The URI.
+    :param next_uri: The next URI.
+    :return: The URI with the next URI set.
+    """
+    uri_p: ParseResult = urlparse(uri)
+    params: list[tuple[str, str]] = parse_qsl(uri_p.query)
+    params = [x for x in params if x[0] == "next"]
+    params.append(("next", next_uri))
+    parts: list[str] = list(uri_p)
+    parts[4] = urlencode(params)
+    return urlunparse(parts)