yesod-dsl-0.1: codegen/prepare-input-field-normal.cg

attr_~{fn} <- case HML.lookup "~{fn}" jsonBodyObj of 
    Just v -> case A.fromJSON v of
        A.Success v' -> return v'
        A.Error err -> sendResponseStatus status400 $ A.object [
                "message" .= ("Could not parse value of type ~{hsFieldType f} from attribute ~{fn} in the JSON object in request body" :: Text),
                "error" .= err
            ]
    Nothing -> sendResponseStatus status400 $ A.object [
            "message" .= ("Expected attribute ~{fn} in the JSON object in request body" :: Text)
        ]