From 3ce2bf6efa5d52250e82caa407b7df693bd7dd51 Mon Sep 17 00:00:00 2001
From: "Phyks (Lucas Verney)" <phyks@phyks.me>
Date: Fri, 25 Dec 2015 22:14:10 +0100
Subject: [PATCH] Add routes for deletion

---
 main.py            |  5 ++-
 routes/__init__.py |  3 +-
 routes/delete.py   | 85 ++++++++++++++++++++++++++++++++++++++++++++++
 routes/post.py     |  7 +++-
 4 files changed, 97 insertions(+), 3 deletions(-)
 create mode 100644 routes/delete.py

diff --git a/main.py b/main.py
index f61a689..b568b23 100755
--- a/main.py
+++ b/main.py
@@ -34,7 +34,6 @@ app.install(plugin)
 
 
 # Routes
-# TODO: Routes for deletion
 @app.get("/")
 def index():
     return tools.APIResponse(tools.pretty_json({
@@ -47,6 +46,10 @@ app.get("/papers/<id:int>/relationships/<name>",
         callback=routes.get.fetch_relationship)
 app.get("/papers/<id:int>/<name>",
         callback=routes.get.fetch_relationship)
+app.route("/papers/<id:int>", method="DELETE",
+          callback=routes.delete.delete_paper)
+app.route("/papers/<id:int>/relationships/<name>", method="DELETE",
+          callback=routes.delete.delete_relationship)
 
 
 app.post("/papers", callback=routes.post.create_paper)
diff --git a/routes/__init__.py b/routes/__init__.py
index 121b1fb..fea823b 100644
--- a/routes/__init__.py
+++ b/routes/__init__.py
@@ -1,4 +1,5 @@
+from . import delete
 from . import get
 from . import post
 
-__all__ = ["get", "post"]
+__all__ = ["delete", "get", "post"]
diff --git a/routes/delete.py b/routes/delete.py
new file mode 100644
index 0000000..cb79a3c
--- /dev/null
+++ b/routes/delete.py
@@ -0,0 +1,85 @@
+"""
+This file contains DELETE routes methods.
+"""
+import bottle
+
+import database
+import json
+import tools
+
+
+def delete_paper(id, db):
+    """
+    Delete a given paper.
+
+    .. code-block:: bash
+
+        DELETE /papers/1
+        Accept: application/vnd.api+json
+
+
+    .. code-block:: bash
+
+        HTTP 204
+
+    :param id: The id of the requested paper to be deleted.
+    :param db: A database session, injected by the ``Bottle`` plugin.
+    :returns: An ``HTTPResponse``.
+    """
+    resource = db.query(database.Paper).filter_by(id=id).first()
+    if resource:
+        db.delete(resource)
+        return tools.APIResponse(status=204, body="")
+    return bottle.HTTPError(404, "Not found")
+
+
+def delete_relationship(id, name, db):
+    """
+    Delete a given relationship
+
+    .. code-block:: bash
+
+        DELETE /papers/1/relationships/cite
+        Content-Type: application/vnd.api+json
+        Accept: application/vnd.api+json
+
+        {
+            "data": [
+                { "type": "cite", "id": "2" },
+                …
+            ]
+        }
+
+
+    .. code-block:: bash
+
+        HTTP 204
+
+    :param id: The id of the requested paper from which the relationship \
+            should be deleted.
+    :param name: The name of the relationship to delete from.
+    :param db: A database session, injected by the ``Bottle`` plugin.
+    :returns: An ``HTTPResponse``.
+    """
+    data = json.loads(bottle.request.body.read().decode("utf-8"))
+    # Validate the request
+    if "data" not in data:
+        return bottle.HTTPError(403, "Forbidden")
+    # Filter data, invalid entries are ignored
+    data = [i for i in data["data"]
+            if "type" in i and i["type"] == name and "id" in i]
+    # Complete replacement (data == []) is forbidden
+    if len(data) == 0:
+        return bottle.HTTPError(403, "Forbidden")
+    # Delete all the requested relationships
+    for i in data:
+        relationship = (db.query(database.Association)
+                        .filter_by(left_id=id, right_id=i["id"])
+                        .filter(database.Relationship.name == name)
+                        .first())
+        if relationship is None:
+            # An error occurred => 403
+            return bottle.HTTPError(403, "Forbidden")
+        db.delete(relationship)
+    # Return an empty 204 on success
+    return tools.APIResponse(status=204, body="")
diff --git a/routes/post.py b/routes/post.py
index 2aa2c70..8d62d7f 100644
--- a/routes/post.py
+++ b/routes/post.py
@@ -44,7 +44,12 @@ def create_paper(db):
                         "self": "/papers/1"
                     },
                     "relationships": {
-                        TODO
+                        "cite": {
+                            "links": {
+                                "related": "/papers/1/relationships/cite"
+                            }
+                        },
+                        …
                     }
                 }
             }