improved API documentation + error handling

src/docs/docs.go

@@ -183,6 +183,12 @@ var doc = `{
                         "schema": {
                             "type": "string"
                         }
+                    },
+                    "400": {
+                        "description": "Bad Request",
+                        "schema": {
+                            "$ref": "#/definitions/api.Error"
+                        }
                     }
                 }
             }

src/docs/swagger.json

@@ -168,6 +168,12 @@
                         "schema": {
                             "type": "string"
                         }
+                    },
+                    "400": {
+                        "description": "Bad Request",
+                        "schema": {
+                            "$ref": "#/definitions/api.Error"
+                        }
                     }
                 }
             }

src/docs/swagger.yaml

@@ -183,6 +183,10 @@ paths:
           description: Image
           schema:
             type: string
+        "400":
+          description: Bad Request
+          schema:
+            $ref: '#/definitions/api.Error'
       summary: Link device and generate QR code.
       tags:
       - Devices