Hi All
The YAML spec[1] has a very nice and standard way of defining custom types
by prefixing any value or object by a `!!<type_name>`. This seems like a
perfect feature for the Brooklyn DSL instead of the `$brooklyn:<command>`.
Let's me explain why.
Right now, a Brooklyn DSL command needs to be written as a string such as:
$brooklyn:formatString("jdbc:%s%s?user=%s\\&password=%s",
component("db").attributeWhenReady("datastore.url"),
"visitors", "brooklyn", "br00k11n")
However, any good YAML library (such as js-yaml[2]) to parse and dump YAML
<--> JSON would wrap this string in quotes because it contains quotes or
reserved characters. That is the expected behaviour based on the
specification[3]. But this is an issue for the Brooklyn parser as the value
will be treated as a `String` and not as a `DslCommand` object.
So my proposal is as follow: support the Brooklyn DSL as a standard custom
YAML type. We obviously need to avoid any quote or reserved characters.
That is relatively simple for commands that takes only one parameter, for
instance:
- $brooklyn:component('my-id') could become
- !brooklyn:component my-id
- $brooklyn:entitySpec would become
- !brooklyn:spec
For the more complex ones, I created a gist[4] that illustrates how this
could work. It is more verbose than the current version but we get a rid of
the hacky `$brooklyn` and comply fully to the YAML specification.
Best.
[1] http://yaml.org/spec/1.2/spec.html
[2] https://github.com/nodeca/js-yaml
[3] http://yaml.org/spec/1.2/spec.html#id2788859
[4] https://gist.github.com/tbouron/67527796726e10689d8d3c34784cd7ec
--
Thomas Bouron • Software Engineer @ Cloudsoft Corporation •
http://www.cloudsoftcorp.com/
Github: https://github.com/tbouron
Twitter: https://twitter.com/eltibouron
