Hello! We have several fragments in different files that each query different fields, but they all n...

# apollo-kotlin

[Eduard Boloș]

Hello! We have several fragments in different files that each query different fields, but they all need to be passed down the same argument, something like:

fragment A on User {
    f1(capabilities: ["CAP1", "CAP2"])
}

fragment B on User {
    f2(capabilities: ["CAP1", "CAP2"])
}

Is there some way to define that argument once, to avoid having to maintain multiple definitions of it? The best idea I had was to use GQL variables, but these fragments are included transitively in many queries, so it's not a very scalable solution 😄

[bod]

hmm I can't think of anything other that variables

[mbonnin]

That'd be a nice use case for parameterized fragments (with default arguments here)

[mbonnin]

Well actually not really because you'd still have to define the default value twice..

[mbonnin]

So we'd need more something like GraphQL preprocessor or so...

[bod]

if these capabilities are usually the same for all clients, the default value could be set on the schema

[Eduard Boloș]

Unfortunately, we have two clients, which can implement certain capabilities at different times 😞
A preprocessor would be nice, indeed.
I guess for the time being it'll stay as it is 😄
Thanks for jumping in so quick!

[Eduard Boloș]

An idea from a colleague, maybe macros would be easier to implement then a full blown preprocessor 😄 Because the bottom line of what we need is just a string interpolation.

[bod]

yeah something very simple could be enough for your case 🙂

[mbonnin]

You could Gradle your way into this: add a preprocessGraphQLFiles that does string replace. That might or might not be worth the extra hoops

[ephemient]

I created a hack for a similar situation in our app: we want all our queries with debugFlags: Optional<List<DebugFlag>> input to have default = Optional.present(getCurrentDebugFlags()). in our case, the easiest thing for me to do was to use a Gradle/AGP transform to rewrite the bytecode