From 89e021bd9d522b87d27dba81eb4e788ea37ba534 Mon Sep 17 00:00:00 2001
From: Sandipsinh Dilipsinh Rathod
 <62684960+ssddOnTop@users.noreply.github.com>
Date: Thu, 25 Jul 2024 21:38:51 +0530
Subject: [PATCH] fix: recursive types on `@graphql` directive (#2528)

---
 src/core/blueprint/operators/graphql.rs       | 21 +++++--
 .../related-fields-recursive.md_client.snap   | 55 +++++++++++++++++++
 .../related-fields-recursive.md_merged.snap   | 23 ++++++++
 tests/execution/related-fields-recursive.md   | 21 +++++++
 4 files changed, 115 insertions(+), 5 deletions(-)
 create mode 100644 tests/core/snapshots/related-fields-recursive.md_client.snap
 create mode 100644 tests/core/snapshots/related-fields-recursive.md_merged.snap
 create mode 100644 tests/execution/related-fields-recursive.md

diff --git a/src/core/blueprint/operators/graphql.rs b/src/core/blueprint/operators/graphql.rs
index 6f057eef8b..74f8282644 100644
--- a/src/core/blueprint/operators/graphql.rs
+++ b/src/core/blueprint/operators/graphql.rs
@@ -1,4 +1,4 @@
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 
 use crate::core::blueprint::FieldDefinition;
 use crate::core::config::{Config, ConfigModule, Field, GraphQL, GraphQLOperationType, Type};
@@ -9,18 +9,29 @@ use crate::core::ir::RelatedFields;
 use crate::core::try_fold::TryFold;
 use crate::core::valid::{Valid, ValidationError, Validator};
 
-fn create_related_fields(config: &Config, type_name: &str) -> RelatedFields {
+fn create_related_fields(
+    config: &Config,
+    type_name: &str,
+    visited: &mut HashSet<String>,
+) -> RelatedFields {
     let mut map = HashMap::new();
+    if visited.contains(type_name) {
+        return RelatedFields(map);
+    }
+    visited.insert(type_name.to_string());
 
     if let Some(type_) = config.find_type(type_name) {
         for (name, field) in &type_.fields {
             if !field.has_resolver() {
-                map.insert(name.clone(), create_related_fields(config, &field.type_of));
+                map.insert(
+                    name.clone(),
+                    create_related_fields(config, &field.type_of, visited),
+                );
             }
         }
     } else if let Some(union_) = config.find_union(type_name) {
         for type_name in &union_.types {
-            map.extend(create_related_fields(config, type_name).0);
+            map.extend(create_related_fields(config, type_name, visited).0);
         }
     };
 
@@ -50,7 +61,7 @@ pub fn compile_graphql(
                 &graphql.name,
                 args,
                 headers,
-                create_related_fields(config, type_name),
+                create_related_fields(config, type_name, &mut HashSet::new()),
             )
             .map_err(|e| ValidationError::new(e.to_string())),
         )
diff --git a/tests/core/snapshots/related-fields-recursive.md_client.snap b/tests/core/snapshots/related-fields-recursive.md_client.snap
new file mode 100644
index 0000000000..e3e1a28ec3
--- /dev/null
+++ b/tests/core/snapshots/related-fields-recursive.md_client.snap
@@ -0,0 +1,55 @@
+---
+source: tests/core/spec.rs
+expression: formatted
+---
+scalar Bytes
+
+scalar Date
+
+scalar Email
+
+scalar Empty
+
+scalar Int128
+
+scalar Int16
+
+scalar Int32
+
+scalar Int64
+
+scalar Int8
+
+scalar JSON
+
+type NodeA {
+  name: String
+  nodeB: NodeB
+}
+
+type NodeB {
+  name: String
+  nodeA: NodeA
+}
+
+scalar PhoneNumber
+
+type Query {
+  queryNodeA: [NodeA]
+}
+
+scalar UInt128
+
+scalar UInt16
+
+scalar UInt32
+
+scalar UInt64
+
+scalar UInt8
+
+scalar Url
+
+schema {
+  query: Query
+}
diff --git a/tests/core/snapshots/related-fields-recursive.md_merged.snap b/tests/core/snapshots/related-fields-recursive.md_merged.snap
new file mode 100644
index 0000000000..fa15978762
--- /dev/null
+++ b/tests/core/snapshots/related-fields-recursive.md_merged.snap
@@ -0,0 +1,23 @@
+---
+source: tests/core/spec.rs
+expression: formatter
+---
+schema @server(hostname: "0.0.0.0", port: 8000) @upstream(baseURL: "http://localhost:8083/graphql") {
+  query: Query
+}
+
+scalar DateTime
+
+type NodeA {
+  name: String
+  nodeB: NodeB
+}
+
+type NodeB {
+  name: String
+  nodeA: NodeA
+}
+
+type Query {
+  queryNodeA: [NodeA] @graphQL(name: "queryNodeA")
+}
diff --git a/tests/execution/related-fields-recursive.md b/tests/execution/related-fields-recursive.md
new file mode 100644
index 0000000000..7e70e3b702
--- /dev/null
+++ b/tests/execution/related-fields-recursive.md
@@ -0,0 +1,21 @@
+```graphql @config
+scalar DateTime
+
+schema @server(port: 8000, hostname: "0.0.0.0") @upstream(baseURL: "http://localhost:8083/graphql") {
+  query: Query
+}
+
+type Query {
+  queryNodeA: [NodeA] @graphQL(name: "queryNodeA", batch: false)
+}
+
+type NodeA {
+  name: String
+  nodeB: NodeB
+}
+
+type NodeB {
+  name: String
+  nodeA: NodeA
+}
+```