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< h1 id = "introspection" > < a class = "header" href = "#introspection" > Introspection< / a > < / h1 >
< blockquote >
< p > The < a href = "https://spec.graphql.org/October2021#sec-Schema-Introspection" > schema introspection< / a > system is accessible from the meta-fields < code > __schema< / code > and < code > __type< / code > which are accessible from the type of the root of a query operation.< / p >
< pre > < code class = "language-graphql" > __schema: __Schema!
__type(name: String!): __Type
< / code > < / pre >
< p > Like all meta-fields, these are implicit and do not appear in the fields list in the root type of the query operation.< / p >
< / blockquote >
< p > < a href = "https://graphql.org" > GraphQL< / a > provides < a href = "https://spec.graphql.org/October2021#sec-Introspection" > introspection< / a > , allowing to see what < a href = "https://spec.graphql.org/October2021#sel-GAFRJBABABF_jB" > queries< / a > , < a href = "https://spec.graphql.org/October2021#sel-GAFRJDABABI5C" > mutations< / a > and < a href = "https://spec.graphql.org/October2021#sel-GAFRJFABABMvpN" > subscriptions< / a > a < a href = "https://graphql.org" > GraphQL< / a > server supports at runtime.< / p >
< p > Because < a href = "https://spec.graphql.org/October2021#sec-Introspection" > introspection< / a > queries are just regular < a href = "https://spec.graphql.org/October2021#sel-GAFRJBABABF_jB" > GraphQL queries< / a > , < a href = "https://docs.rs/juniper" > Juniper< / a > supports them natively. For example, to get all the names of the types supported, we could < a href = "https://spec.graphql.org/October2021#sec-Execution" > execute< / a > the following < a href = "https://spec.graphql.org/October2021#sel-GAFRJBABABF_jB" > query< / a > against < a href = "https://docs.rs/juniper" > Juniper< / a > :< / p >
< pre > < code class = "language-graphql" > {
__schema {
types {
name
}
}
}
< / code > < / pre >
< h2 id = "disabling" > < a class = "header" href = "#disabling" > Disabling< / a > < / h2 >
< blockquote >
< p > Disabling introspection in production is a widely debated topic, but we believe it’ < / p >
< / blockquote >
2024-03-20 16:31:17 -05:00
< p > < a href = "https://www.apollographql.com/blog/why-you-should-disable-graphql-introspection-in-production" > Some security requirements and considerations< / a > may mandate to disable < a href = "https://spec.graphql.org/October2021#sec-Schema-Introspection" > GraphQL schema introspection< / a > in production environments. In < a href = "https://docs.rs/juniper" > Juniper< / a > this can be achieved by using the < a href = "https://docs.rs/juniper/0.16.0/juniper/struct.RootNode.html#method.disable_introspection" > < code > RootNode::disable_introspection()< / code > < / a > method:< / p >
2024-03-20 11:02:18 -05:00
< pre > < pre class = "playground" > < code class = "language-rust edition2021" > < span class = "boring" > extern crate juniper;
< / span > < span class = "boring" > use juniper::{
< / span > < span class = "boring" > graphql_object, graphql_vars, EmptyMutation, EmptySubscription, GraphQLError,
< / span > < span class = "boring" > RootNode,
< / span > < span class = "boring" > };
< / span > < span class = "boring" >
< / span > pub struct Query;
#[graphql_object]
impl Query {
fn some() -> bool {
true
}
}
type Schema = RootNode< 'static, Query, EmptyMutation, EmptySubscription> ;
fn main() {
let schema = Schema::new(Query, EmptyMutation::new(), EmptySubscription::new())
.disable_introspection();
let query = "query { __schema { queryType { name } } }";
match juniper::execute_sync(query, None, & schema, & graphql_vars! {}, & ()) {
Err(GraphQLError::ValidationError(errs)) => {
assert_eq!(
errs.first().unwrap().message(),
"GraphQL introspection is not allowed, but the operation contained `__schema`",
);
}
res => panic!("expected `ValidationError`, returned: {res:#?}"),
}
}< / code > < / pre > < / pre >
< blockquote >
< p > < strong > NOTE< / strong > : Attempt to execute an < a href = "https://spec.graphql.org/October2021#sec-Schema-Introspection" > introspection query< / a > results in < a href = "https://spec.graphql.org/October2021#sec-Validation" > validation< / a > error, rather than < a href = "https://spec.graphql.org/October2021#sec-Execution" > execution< / a > error.< / p >
< / blockquote >
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