Coercing variables

[freiksenet]

Currently Scalar types have two methods coerce and coerceLiteral. coerceLiteral is used to create a javascript value from ast, coerce is used both on variables and on data received from resolve in executors.

Unfortunately that is not enough - variables usually come from some format like json which wouldn't always support all the new scalar types and most likely will return them as string. On the other hand, eg, databases might return types in javascript format already. Therefore coerce can't support both variable coercion and execution coercion.

@leebyron suggested that for variable coercion, a new method is added to the Scalars - coerceVariable.

[freiksenet]

Okay, so we cleared it with @leebyron. coerce is actually a function that should do serialization. We've agreed to rename coerce to serialize, rename coerceLiteral to parseLiteral and add parseVariable.

I'll try to make a PR asap.

[leebyron]

Merged in! this will be in the next release.

[dashed]

These changes should reflect onto the docs: http://graphql.org/docs/api-reference-type-system/#graphqlscalartype

When playing with graphql-js, I got super confused on why coerce stuff was missing and not working.