[WIP] Exception handling

app/controller/__init__.py

@@ -1,10 +1,13 @@
 from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
+from sqlalchemy.exc import IntegrityError
 
 from app.api.cruds.base import create, read, update, delete, read_all
 from app.schema.library import Library
 from ..db.config.config import get_engine_configuration
 
+from .exceptions import LibraryCreationException
+
 import logging
 logging.basicConfig(level=logging.DEBUG)
 logger = logging.getLogger(__name__)
@@ -66,7 +69,16 @@ class LibraryController:
         return False
     
     def create(self, library:Library):
-        self._library = create(self.session, library)
+        try:
+            self._library = create(self.session, library)
+        except IntegrityError as e:
+            raise LibraryCreationException(
+                "Cannot create library",
+                f"{e.orig}", 
+                "library",
+                str(library),
+                400
+            )
         return self
     
     def read(self, _id):

app/controller/exceptions/__init__.py

@@ -0,0 +1,2 @@
+from .base import LibraryExceptionBase
+from .exc_01001X_create import LibraryCreationException

app/controller/exceptions/base.py

@@ -0,0 +1,18 @@
+class LibraryExceptionBase(Exception):
+    def __init__(self, code, error):
+        self.code = code
+        self.error = error
+    
+    def to_dict(self):
+        return {
+            "status": "error",
+            "code": self.code,
+            "error": self.error,
+            "status_code": 400
+        }
+    
+    def __str__(self):
+        return f"ERROR {self.code}: {self.error}"
+    
+    def __repr__(self):
+        return f"LibraryExceptionBase(code={self.code!r}, error={self.error!r})"

app/controller/exceptions/exc_01001X_create.py

@@ -0,0 +1,26 @@
+from .base import LibraryExceptionBase
+
+#010010
+class LibraryCreationException(LibraryExceptionBase):
+    def __init__(self, name, error, object, data, status_code=400):
+        self.code = "010010"
+        self.name = name
+        self.error = error
+        self.object = object
+        self.data = data
+        self.status_code = status_code
+
+    def to_dict(self):
+        return {
+            "status": "error",
+            "name": self.name,
+            "code": self.code,
+            "error": self.error,
+            "object": self.object,
+            "data": self.data,
+            "status_code": self.status_code
+        }
+    
+    def __repr__(self):
+        return f"LibraryCreationException(code={self.code!r}, error={self.error!r}), " \
+               f"object={self.object!r}, data={self.data!r}"

app/routes/__init__.py

@@ -1 +1,39 @@
+from flask import json, make_response
+from werkzeug.exceptions import HTTPException
+
 from .api import api
+from ..controller.exceptions import LibraryExceptionBase
+
+@api.errorhandler(LibraryExceptionBase)
+def handle_exception(e):
+    """Return JSON instead of HTML for HTTP errors."""
+    # start with the correct headers and status code from the error
+    response = make_response()
+    # replace the body with JSON
+    response.data = json.dumps({
+        "status": "error",
+        "code": e.code,
+        "status_code": e.status_code,
+        "name": e.name,
+        "error": e.error,
+    })
+    response.content_type = "application/json"
+    response.status_code = e.status_code
+    return response
+
+@api.errorhandler(HTTPException)
+def handle_exception(e):
+    """Return JSON instead of HTML for HTTP errors."""
+    # start with the correct headers and status code from the error
+    response = e.get_response()
+    # replace the body with JSON
+    response.data = json.dumps({
+        "status": "error",
+        "code": f"000{e.code}",
+        "status_code": e.code,
+        "name": e.name,
+        "error": e.description,
+    })
+    response.content_type = "application/json"
+    return response
+

app/routes/api/library/create.py

@@ -11,18 +11,10 @@ logger = logging.getLogger(__name__)
 
 @api_library.route("/", methods=["POST"])
 def create_library():
-    try:
-        data = request.json
-    except Exception as e:
-        logger.debug(f"{e}")
-        return { "status": "error", "error": "JSON Required" }, 415 
+    
+    data = request.json
     
     with LibraryController() as controller:
-        try:
-            lib = Library(**data)
-            library = controller.create(lib)
-        except IntegrityError as e:
-            logger.debug(f"DB Error Creating {e}")
-            return { "status": "error", "error": f"{e.orig}" }, 400
-        else:     
-            return { "status": "ok", "result": library.data.to_dict() }, 200
+        lib = Library(**data)
+        library = controller.create(lib)
+        return { "status": "ok", "result": library.data.to_dict() }, 200