Adding delegate for Get instance + tests
diff --git a/rackspace/db/v1/instances/fixtures.go b/rackspace/db/v1/instances/fixtures.go
index 79537ab..ac2471e 100644
--- a/rackspace/db/v1/instances/fixtures.go
+++ b/rackspace/db/v1/instances/fixtures.go
@@ -9,6 +9,45 @@
 	fake "github.com/rackspace/gophercloud/testhelper/client"
 )
 
+const singleInstanceJson = `
+{
+  "instance": {
+    "created": "2014-02-13T21:47:13",
+    "datastore": {
+      "type": "mysql",
+      "version": "5.6"
+    },
+    "flavor": {
+      "id": "1",
+      "links": [
+        {
+          "href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
+          "rel": "self"
+        },
+        {
+          "href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
+          "rel": "bookmark"
+        }
+      ]
+    },
+    "links": [
+      {
+        "href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
+        "rel": "self"
+      }
+    ],
+    "hostname": "e09ad9a3f73309469cf1f43d11e79549caf9acf2.rackspaceclouddb.com",
+    "id": "d4603f69-ec7e-4e9b-803f-600b9205576f",
+    "name": "json_rack_instance",
+    "status": "BUILD",
+    "updated": "2014-02-13T21:47:13",
+    "volume": {
+      "size": 2
+    }
+  }
+}
+`
+
 func HandleCreateInstanceSuccessfully(t *testing.T) {
 	th.Mux.HandleFunc("/instances", func(w http.ResponseWriter, r *http.Request) {
 		th.TestMethod(t, r, "POST")
@@ -51,43 +90,17 @@
 }
 `)
 
-		fmt.Fprintf(w, `
-{
-  "instance": {
-    "created": "2014-02-13T21:47:13",
-    "datastore": {
-      "type": "mysql",
-      "version": "5.6"
-    },
-    "flavor": {
-      "id": "1",
-      "links": [
-        {
-          "href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
-          "rel": "self"
-        },
-        {
-          "href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
-          "rel": "bookmark"
-        }
-      ]
-    },
-		"links": [
-			{
-				"href": "https://ord.databases.api.rackspacecloud.com/v1.0/1234/flavors/1",
-				"rel": "self"
-			}
-		],
-    "hostname": "e09ad9a3f73309469cf1f43d11e79549caf9acf2.rackspaceclouddb.com",
-    "id": "d4603f69-ec7e-4e9b-803f-600b9205576f",
-    "name": "json_rack_instance",
-    "status": "BUILD",
-    "updated": "2014-02-13T21:47:13",
-    "volume": {
-      "size": 2
-    }
-  }
+		fmt.Fprintf(w, singleInstanceJson)
+	})
 }
-`)
+
+func HandleGetInstanceSuccessfully(t *testing.T, id string) {
+	th.Mux.HandleFunc("/instances/"+id, func(w http.ResponseWriter, r *http.Request) {
+		th.TestMethod(t, r, "GET")
+		th.TestHeader(t, r, "X-Auth-Token", fake.TokenID)
+
+		w.Header().Add("Content-Type", "application/json")
+
+		fmt.Fprintf(w, singleInstanceJson)
 	})
 }