Add support for DELETE verb

Fixes #125

test/Feature/DeleteSpec.hs

@@ -0,0 +1,37 @@
+module Feature.DeleteSpec where
+
+import Test.Hspec
+import Test.Hspec.Wai
+import SpecHelper
+
+import Network.HTTP.Types
+
+spec :: Spec
+spec = beforeAll (clearTable "items" >> createItems 15) . afterAll_ (clearTable "items")
+  . around withApp $
+  describe "Deleting" $ do
+    context "existing record" $ do
+      it "succeeds with 204 and deletion count" $
+        request methodDelete "/items?id=eq.1" [] ""
+          `shouldRespondWith` ResponseMatcher {
+            matchBody    = Nothing
+          , matchStatus  = 204
+          , matchHeaders = ["Content-Range" <:> "*/1"]
+          }
+
+      it "actually clears items ouf the db" $ do
+        _ <- request methodDelete "/items?id=lt.15" [] ""
+        get "/items"
+          `shouldRespondWith` ResponseMatcher {
+            matchBody    = Just "[{\"id\":15}]"
+          , matchStatus  = 200
+          , matchHeaders = ["Content-Range" <:> "0-0/1"]
+          }
+
+    context "known route, unknown record" $
+      it "fails with 404" $
+        request methodDelete "/items?id=eq.101" [] "" `shouldRespondWith` 404
+
+    context "totally unknown route" $
+      it "fails with 404" $
+        request methodDelete "/foozle?id=eq.101" [] "" `shouldRespondWith` 404