scaffold options

resty-generators will add some more options to the scaffold/model generators.

• singleton
• timestamps
• modified-by
• optimistic
• readonly - (pending)

the first three will affect the signature of a model, i.e. the gwt editor of a model has a read only attributes for each model: id, created_at, updated_at, modified_by. these attributes of model comes in with one of the following option.

• id: singleton
• created_at, updated_at: timestamps
• modified_by: modified-by

the modified class will be User that is hard coded right now. this is class with couple of attributes - no AR or DM or any other persistent framework in place.

the optimistic option needs to have timestamps as well and is merely something for the controller. when finding an existing model the updated_at timestamps must match as well, otherwise the model is stale (if there is a model for the given id). stale model can not be saved or deleted and will response with a conflict http status. AR offers this via an explicit version column and this here is reusing the existing updated_at column.

belongs to relations

rails generate scaffold location name:string country:belongs_to

will use Country as belongs_to class both on the rails side as well on GWT side. the editors for that location will have a dropdown list with countries to select a country, i.e. the whole round with creating, updating and deleting such model with belongs_to gets scaffolded and is ready to use.

gwt classes of scaffolded resource

src/main/java/com/example/client/ ├── activities │   └── AccountActivity.java ├── editors │   ├── AccountEditor.java │   └── AccountEditor.ui.xml ├── events │   ├── AccountEventHandler.java │   └── AccountEvent.java ├── models │   └── Account.java ├── places │   ├── AccountPlace.java │   └── AccountPlaceTokenizer.java ├── restservices │   └── AccountsRestService.java └── views ├── AccountViewImpl.java ├── AccountView.java └── AccountView.ui.xml

• activities: loads the data from server and fires respective events, pushes the response into the view, etc
• editors: is input form for the model
• model: data and maybe more logic
• places: the tokenizer maps the url pattern to a place
• restservices: the transport layer for the model to server
• views: adds save, create, new, delete, etc buttons and the actual editor, or the list of models.
• *.ui.xml files are the GWT template files

see also on the GWT website for activites + places or editors or GWT templates.

how a new resource gets plugged in

google-gin is used to wire all components together. most of the generated components all GIN bindings are done via annotations.

the code points which plugs in all the classes for a new resource (Account in the list below) are (where the application name is MyApp):

• src/main/java/com/example/client/managed/MyAppPlaceHistoryMapper.java which gets the history tokenizer registered for the new resource
• src/main/java/com/example/client/managed/ActivityFactory.java which is a parametrizied gin-factory. this allows the AccountActivity to be managed by GIN
• src/main/java/com/example/client/managed/MyAppMenuPanel.java is just a list of buttons which triggers a PlaceController.goTo(Place)
• src/main/java/com/example/client/managed/MyAppModule.java gets a provider to make the AccountsRestService a singleton and adds the AccountActivity to the ActivityFactory