Dan Haywood created ISIS-369:
--------------------------------
Summary: GSOC2013: A domain-specific language aligned with the
Apache Isis programming conventions.
Key: ISIS-369
URL: https://issues.apache.org/jira/browse/ISIS-369
Project: Isis
Issue Type: New Feature
Reporter: Dan Haywood
Assignee: Dan Haywood
>From our website (http://isis.apache.org):
Apache Isis™ software is a framework for rapidly developing domain-driven apps
in Java. Write your business logic in entities, domain services and
repositories, and the framework dynamically generates a representation of that
domain model as a webapp or a RESTful API. Use for prototyping or production.
~~~
Isis works by building a metamodel from the domain object models, where these
follow a number of straightforward programming conventions (basically, pojos +
some annotations, see our cheat sheet
[http://isis.apache.org/getting-started/cheat-sheet.html]).
A discussion that's we've had on the mailing list a few times is to support a
DSL tailored to these conventions, that would compile down to the same bytecode.
A good candidate technology, we suspect, is Eclipse's XText
[http://www.eclipse.org/Xtext/].
And below is a sketch of what that DSL might look like.
For entities:
@... // annotations here
entity Customer {
...
ProductRepository products;
OrderRepository orders;
}
where:
- the products, orders imply an instance variable and a setter to allow
services to be injected into
- DomainObjectContainer container is provided automatically as a field
For entity properties:
entity Customer {
@ ... // annotations here
property String firstName {
set;
modify { ... }
clear { }
default { ... }
choices { ... }
hide { ... }
disable { ... }
validate { ... }
}
}
where
- property is a keyword
- String firstName
- implies the instance variable and the getter
- annotations can be specified, apply to the getter
- set;
- is optional,
- if present implies the setter (and so is a non-derived property)
- syntax borrowed from C#
- modify { ... }
- is optional
- if present, implies the modifyXxx(String value) method
- 'value' would be an implicitly available locally scoped parameter
- clear { ... }
- is optional
- if present, implies the void clearXxx() method
- default { ... }
- is optional
- if present, implies the String defaultXxx() method
- choices { ... }
- is optional
- if present, implies the List<String> choicesXxx() method
- hide { ... }
- is optional
- if present, implies the boolean clearXxx() method
- disable { ... }
- is optional
- if present, implies the String disableXxx() method
- validate { ... }
- is optional
- if present, implies the String validateXxx(String value) method
- 'value' would be an implicitly available locally scoped parameter
similarly for entity collections:
entity Customer {
@ ... // annotations here
collection List<Order> orders {
addTo { ... }
removeFrom { }
hide { ... }
disable { ... }
validateAddTo { ... }
validateRemoveFrom { ... }
}
}
where
- collection is a keyword
- otherwise similarly as properties
and similarly for entity actions:
entity Customer {
@... // annotations here
action Order placeOrder(
Product product {
default { }
choices { }
validate { }
},
int quantity {
default { }
choices { }
validate { }
}
) {
body { ... }
hide { ... }
disable { ... }
validate { ... }
}
}
where
- the name of the parameter would imply @Named(...)
- the default, choices, validate for the parameters apply to that parameter
- imply corresponding defaultNXxx(), choicesNXxx, validateNXxx()
- where N = parameter number
- body { ... }
- is the action body, with the parameters defined
- hide, disable
- similarly
- validate (at action level)
- corresponds to validateXxx(...)
- to validate the set of arguments rather than an individual parameter
Any members that do not follow the above rules are just copied over "as-is"
into Java.
~~~~~~~~~~~~
For values:
value FractionalNumber {
int numerator;
int denominator;
}
is basically the same as Lombok @Data
requires information in @ValueSemanticsProvider to be specified (somehow, not
sure exactly how)
~~~~~~~~~~~~
For services/repositories:
service ProductRepository {
}
where:
- any services are injected into as for entities
- DomainObjectContainer container is provided for free, again as for entities
- actions as for entities
- properties and collections are disallowed
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
