Juniper: export .graphql schema

[lkoelman]

Is there currently a way to export the graphql schema that is implicit in the annotated rust code to a .graphql file?

I would like to have a single source of truth for my schema, and this would be a practical way to achieve this. Another approach that I considered was using juniper-from-schema and defining the single source of truth in a .graphql file. However, this doesn't seem to be as flexible in regards to re-using the datatypes inside rust for other purposes.

[tyranron]

@lkoelman we're using something like that:

//! Binary which exports server's GraphQL schema into a JSON file.
//!
//! # Usage
//!
//! ```bash
//! cargo run --bin export_schema
//! ```

use std::{fs, io};

/// Runs application by performing introspection GraphQL query onto current
/// GraphQL schema of application and writes result into `graphql.schema.json`
/// file in the project's root.
fn main() -> io::Result<()> {
    let (res, _) = juniper::introspect(
        &my_api_graphql::schema::new(),
        &my_api_graphql::dumb::context(),
        juniper::IntrospectionFormat::default(),
    )
    .expect("Failed to execute introspection query");

    fs::write(
        "graphql.schema.json",
        // "data" wrapping is required by GraphDoc.
        // See: https://github.com/2fd/graphdoc/issues/54
        format!(r#"{{"data":{}}}"#, serde_json::to_string_pretty(&res)?),
    )?;

    Ok(())
}

[LegNeato]

It's even easier using master! Check out https://graphql-rust.github.io/juniper/master/schema/schemas_and_mutations.html#outputting-schemas-in-the-a-hrefhttpsgraphqlorglearnschematype-languagegraphql-schema-languagea

[LegNeato]

RootNode now has an as_schema_language() function that should do what you want.

[lkoelman]

@LegNeato Thank you, this is exactly what I was looking for.

[LegNeato]

Great, hope it works. I wrote that support so please open another issue if there are bugs with it!

[auryn31]

I cannot find the function as_schema_language() in version juniper = "^0.14.2"

Is it still available?

My Schema looks like this:

pub type Schema = RootNode<'static, QueryRoot, MutationRoot>;

[tyranron]

@auryn31 unfortunately, it's available on master only.

[auryn31]

Oh ok
Thanks