Explicitly remap the supergraph config (#614)

## Description

With #613 merged, it is safe to create an `__globals` subgraph into
which we can sort all supergraph config. This PR gives supergraph
objects a qualified name (using the `__globals` subgraph). Note that
outside of debugging/tracing, this is functionally a no-op: we strip the
subgraph from the objects as soon as we use them, because the global
nature of the config means that this is irrelevant information.

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- [x] community-edition
- [x] cloud
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- [ ] enhancement
- [ ] bugfix
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- [ ] performance-enhancement
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Metadata config declared under the `supergraph` field will now appear as
part of an `__globals` subgraph in tracing. Note that the field can also
be omitted and the config placed in a user-named subgraph.

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V3_GIT_ORIGIN_REV_ID: 84d2beed98f843df246c8562188cdf7de63643fc

v3/crates/metadata-resolve/src/stages/graphql_config/mod.rs

@@ -1,7 +1,9 @@
+//! This is where we will resolve graphql configuration
+
 use crate::helpers::types::mk_name;
-/// this is where we will resolve graphql configuration
 use crate::types::error::{Error, GraphqlConfigError};
 use lang_graphql::ast::common as ast;
+use open_dds::accessor::QualifiedObject;
 use open_dds::graphql_config::{self, OrderByDirection};
 use serde::{Deserialize, Serialize};
 
@@ -68,7 +70,7 @@ pub struct GraphqlConfig {
 ///       that that object is mandatory) throw an error
 ///     * if the flag is not set, use the fallback object
 pub fn resolve(
-    graphql_configs: &Vec<graphql_config::GraphqlConfig>,
+    graphql_configs: &Vec<QualifiedObject<graphql_config::GraphqlConfig>>,
     flags: &open_dds::flags::Flags,
 ) -> Result<GraphqlConfig, Error> {
     if graphql_configs.is_empty() {
@@ -82,7 +84,9 @@ pub fn resolve(
     } else {
         match graphql_configs.as_slice() {
             // There should only be one graphql config in supergraph
-            [graphql_config] => resolve_graphql_config(graphql_config),
+            // Because this config can only be defined in once in a supergraph, it doesn't actually
+            // matter which subgraph defines it: the outcome will be the same.
+            [graphql_config] => resolve_graphql_config(&graphql_config.object),
             _ => Err(Error::GraphqlConfigError {
                 graphql_config_error: GraphqlConfigError::MultipleGraphqlConfigDefinition,
             }),

v3/crates/open-dds/src/accessor.rs

@@ -39,7 +39,7 @@ pub struct MetadataAccessor {
     pub command_permissions: Vec<QualifiedObject<permissions::CommandPermissionsV1>>,
     pub flags: flags::Flags,
     // `graphql_config` is a vector because we want to do some validation depending on the presence of the object
-    pub graphql_config: Vec<graphql_config::GraphqlConfig>,
+    pub graphql_config: Vec<QualifiedObject<graphql_config::GraphqlConfig>>,
 }
 
 fn load_metadata_objects(
@@ -55,8 +55,9 @@ fn load_metadata_objects(
                     .push(QualifiedObject::new(subgraph, data_connector.upgrade()));
             }
             OpenDdSubgraphObject::GraphqlConfig(graphql_config) => {
-                // TODO: we need to map this into a "virtual subgraph"
-                accessor.graphql_config.push(graphql_config);
+                accessor
+                    .graphql_config
+                    .push(QualifiedObject::new(subgraph, graphql_config));
             }
             OpenDdSubgraphObject::ObjectType(object_type) => {
                 accessor
@@ -130,7 +131,9 @@ fn load_metadata_supergraph_object(
 ) {
     match supergraph_object {
         OpenDdSupergraphObject::GraphqlConfig(graphql_config) => {
-            accessor.graphql_config.push(graphql_config);
+            accessor
+                .graphql_config
+                .push(QualifiedObject::new("__globals", graphql_config));
         }
     }
 }