transit-ruby. Change casing between snake_case, hyphens when reading/writing

[Daniel Marjenburgh]

Hello,

Is there a way to make Transit emit the keys of hashes to use hyphens when it is a Symbol?

For example, the following happens:

w = Transit::Writer.new(:json, STDOUT)

w.write({a_b: 1})

# => ["^ ","~:a_b",1]

I would like to configure the writer to emit:

# => ["^ ","~:a-b",1]

Is there a way to do this without resorting to writing the hash as {:"a-b" => 1} ?

Alternatively, is there a way to configure the reader in transit-clj to convert keywords like :a_b to :a-b?

Thanks

[David Chelimsky]

You can handle this in (at least) 3 ways:

1 - coerce transit-ruby to write ruby Symbols differently via a custom write handler

2 - coerce transit-clj to read transit keywords differently via a custom read handler

3 - introduce a new type in your Ruby app to wrap your map keys and add a custom write handler for that type

I'd probably lean toward the 3rd option, as that avoids the risk you'd be introducing by changing a core behavior in the 1st and 2nd options (akin to the risks of monkey patching).

Either way, take a look at http://blog.cognitect.com/blog/2015/9/10/extending-transit and http://www.rubydoc.info/gems/transit-ruby/Transit/WriteHandlers for more info about custom handlers. Feel free to post back to this thread if you have any questions about any of this.

Cheers,

David

[Daniel Marjenburgh]

I have found the answer to the alternative, by passing:

{:handlers {":" (transit/read-handler
                  (fn [o] (keyword (.replaceAll ^String o "_" "-"))))}}

[Daniel Marjenburgh]

Thank you David.