auth: Reorganise modules/packages for easier dev and maintenance

Split the views/routes into separate modules each dealing with a narrower
scope of the application to aid in maintenance, and help with making the
development easier.

2 files changed, 149 insertions, 0 deletions

diff --git a/gn3/auth/authorisation/users/__init__.py b/gn3/auth/authorisation/users/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/gn3/auth/authorisation/users/__init__.py
diff --git a/gn3/auth/authorisation/users/views.py b/gn3/auth/authorisation/users/views.py
new file mode 100644
index 0000000..460f81c
--- /dev/null
+++ b/gn3/auth/authorisation/users/views.py
@@ -0,0 +1,149 @@
+"""User authorisation endpoints."""
+import traceback
+from typing import Tuple, Optional
+
+import sqlite3
+from flask import request, jsonify, Response, Blueprint, current_app
+
+from gn3.auth import db
+from gn3.auth.dictify import dictify
+
+from ..groups.models import user_group as _user_group
+from ..errors import NotFoundError, UserRegistrationError
+from ..resources.models import user_resources as _user_resources
+from ..roles.models import assign_default_roles, user_roles as _user_roles
+
+from ...authentication.oauth2.resource_server import require_oauth
+from ...authentication.users import save_user, set_user_password
+from ...authentication.oauth2.models.oauth2token import token_by_access_token
+
+users = Blueprint("users", __name__)
+
+@users.route("/", methods=["GET"])
+@require_oauth("profile")
+def user_details() -> Response:
+    """Return user's details."""
+    with require_oauth.acquire("profile") as the_token:
+        user = the_token.user
+        user_dets = {
+            "user_id": user.user_id, "email": user.email, "name": user.name,
+            "group": False
+        }
+        with db.connection(current_app.config["AUTH_DB"]) as conn, db.cursor(conn) as cursor:
+            the_group = _user_group(cursor, user).maybe(# type: ignore[misc]
+                False, lambda grp: grp)# type: ignore[arg-type]
+            return jsonify({
+                **user_dets,
+                "group": dictify(the_group) if the_group else False
+            })
+
+@users.route("/roles", methods=["GET"])
+@require_oauth("role")
+def user_roles() -> Response:
+    """Return the non-resource roles assigned to the user."""
+    with require_oauth.acquire("role") as token:
+        with db.connection(current_app.config["AUTH_DB"]) as conn:
+            return jsonify(tuple(
+                dictify(role) for role in
+                _user_roles(conn, token.user).maybe(# type: ignore[misc]
+                    tuple(), lambda roles: roles)))
+
+def __email_valid__(email: str) -> Tuple[bool, Optional[str]]:
+    """Validate the email address."""
+    if email == "":
+        return False, "Empty email address"
+
+    ## Check that the address is a valid email address
+    ## Review use of `email-validator` or `pyIsEmail` python packages for
+    ## validating the emails, if it turns out this is important.
+
+    ## Success
+    return True, None
+
+def __password_valid__(password, confirm_password) -> Tuple[bool, Optional[str]]:
+    if password == "" or confirm_password == "":
+        return False, "Empty password value"
+
+    if password != confirm_password:
+        return False, "Mismatched password values"
+
+    return True, None
+
+def __user_name_valid__(name: str) -> Tuple[bool, Optional[str]]:
+    if name == "":
+        return False, "User's name not provided."
+
+    return True, None
+
+def __assert_not_logged_in__(conn: db.DbConnection):
+    bearer = request.headers.get('Authorization')
+    if bearer:
+        token = token_by_access_token(conn, bearer.split(None)[1]).maybe(# type: ignore[misc]
+            False, lambda tok: tok)
+        if token:
+            raise UserRegistrationError(
+                "Cannot register user while authenticated")
+
+@users.route("/register", methods=["POST"])
+def register_user() -> Response:
+    """Register a user."""
+    with db.connection(current_app.config["AUTH_DB"]) as conn:
+        __assert_not_logged_in__(conn)
+
+        form = request.form
+        email = form.get("email", "").strip()
+        password = form.get("password", "").strip()
+        user_name = form.get("user_name", "").strip()
+        errors = tuple(
+                error for valid,error in
+            [__email_valid__(email),
+             __password_valid__(
+                 password, form.get("confirm_password", "").strip()),
+             __user_name_valid__(user_name)]
+            if not valid)
+        if len(errors) > 0:
+            raise UserRegistrationError(*errors)
+
+        try:
+            with db.cursor(conn) as cursor:
+                user, _hashed_password = set_user_password(
+                    cursor, save_user(cursor, email, user_name), password)
+                assign_default_roles(cursor, user)
+                return jsonify(
+                    {
+                        "user_id": user.user_id,
+                        "email": user.email,
+                        "name": user.name
+                    })
+        except sqlite3.IntegrityError as sq3ie:
+            current_app.logger.debug(traceback.format_exc())
+            raise UserRegistrationError(
+                "A user with that email already exists") from sq3ie
+
+    raise Exception(
+        "unknown_error", "The system experienced an unexpected error.")
+
+@users.route("/group", methods=["GET"])
+@require_oauth("profile group")
+def user_group() -> Response:
+    """Retrieve the group in which the user is a member."""
+    with require_oauth.acquire("profile group") as the_token:
+        db_uri = current_app.config["AUTH_DB"]
+        with db.connection(db_uri) as conn, db.cursor(conn) as cursor:
+            group = _user_group(cursor, the_token.user).maybe(# type: ignore[misc]
+                False, lambda grp: grp)# type: ignore[arg-type]
+
+        if group:
+            return jsonify(dictify(group))
+        raise NotFoundError("User is not a member of any group.")
+
+@users.route("/resources")
+@require_oauth("profile resource")
+def user_resources() -> Response:
+    """Retrieve the resources a user has access to."""
+    with require_oauth.acquire("profile resource") as the_token:
+        db_uri = current_app.config["AUTH_DB"]
+        with db.connection(db_uri) as conn:
+            return jsonify([
+                dictify(resource) for resource in
+                _user_resources(conn, the_token.user)])