Order returned TypeInstances by path:revision and createdAt (#641)

hub-js/graphql/local/examples.graphql

@@ -162,6 +162,9 @@ mutation DeleteLockedTypeInstance($typeInstanceID: ID!) {
 
 fragment TypeInstance on TypeInstance {
   id
+  createdAt {
+    formatted
+  }
   typeRef {
     path
     revision

hub-js/graphql/local/schema.graphql

@@ -12,6 +12,11 @@ directive @cypher(statement: String) on FIELD_DEFINITION
 directive @index on FIELD_DEFINITION
 directive @id on FIELD_DEFINITION
 
+"""
+Represents date, time and time zone
+"""
+scalar DateTime
+
 """
 Arbitrary data
 """
@@ -34,16 +39,30 @@ scalar LockOwnerID
 
 type TypeInstance {
   id: ID! @id
-
+  createdAt: DateTime
   lockedBy: LockOwnerID
 
   """
   Common properties for all TypeInstances which cannot be changed
   """
   typeRef: TypeInstanceTypeReference!
     @relation(name: "OF_TYPE", direction: "OUT")
-  uses: [TypeInstance!]! @relation(name: "USES", direction: "OUT")
-  usedBy: [TypeInstance!]! @relation(name: "USES", direction: "IN")
+  """
+  Returns TypeInstances that are used. List is sorted by TypeInstance's TypeRef path in ascending order, and then by revision in descending order (newest revision are first).
+  If both TypeRef path and revision are same, then it's additionally sorted by TypeInstance createdAt field (newly created are first).
+  """
+  uses: [TypeInstance!]!
+    @cypher(
+      statement: "MATCH (this)-[:USES]->(ti:TypeInstance)-[:OF_TYPE]-(tr: TypeInstanceTypeReference) RETURN ti ORDER BY tr.path ASC, tr.revision DESC, ti.createdAt DESC"
+    )
+  """
+  Returns TypeInstances that uses this TypeInstance. List is sorted by TypeInstance's TypeRef path in ascending order, and then by revision in descending order (newest revision are first).
+  If both TypeRef path and revision are same, then it's additionally sorted by TypeInstance createdAt field (newly created are first).
+  """
+  usedBy: [TypeInstance!]!
+    @cypher(
+      statement: "MATCH (this)<-[:USES]-(ti:TypeInstance)-[:OF_TYPE]-(tr: TypeInstanceTypeReference) RETURN ti ORDER BY tr.path ASC, tr.revision DESC, ti.createdAt DESC"
+    )
   backend: TypeInstanceBackendReference! @relation(name: "STORED_IN", direction: "OUT")
 
   latestResourceVersion: TypeInstanceResourceVersion
@@ -286,6 +305,10 @@ input UnlockTypeInstancesInput {
 }
 
 type Query {
+  """
+  Returns all TypeInstances. List is sorted by TypeInstance's TypeRef path in ascending order, and then by revision in descending order (newest revision are first).
+  If both TypeRef path and revision are same, then it's additionally sorted by TypeInstance createdAt field (newly created are first).
+  """
   typeInstances(filter: TypeInstanceFilter = {}): [TypeInstance!]!
     @cypher(
       statement: """
@@ -334,7 +357,9 @@ type Query {
         )
       )
 
-      RETURN DISTINCT ti
+      WITH DISTINCT ti, typeRef
+      ORDER BY typeRef.path ASC, typeRef.revision DESC, ti.createdAt DESC
+      RETURN ti
       """
     )
 
@@ -356,7 +381,7 @@ type Mutation {
   createTypeInstance(in: CreateTypeInstanceInput!): TypeInstance!
     @cypher(
       statement: """
-      CREATE (ti:TypeInstance {id: apoc.create.uuid()})
+      CREATE (ti:TypeInstance {id: apoc.create.uuid(), createdAt: datetime()})
 
       // Backend
       WITH *

hub-js/src/schema/local.ts

@@ -73,7 +73,7 @@ export const schema = makeAugmentedSchema({
               // create TypeInstances
               const createTypeInstanceResult = await tx.run(
                 `UNWIND $typeInstances AS typeInstance
-               CREATE (ti:TypeInstance {id: apoc.create.uuid()})
+               CREATE (ti:TypeInstance {id: apoc.create.uuid(), createdAt: datetime()})
 
                // Backend
                WITH *
@@ -500,6 +500,7 @@ export async function ensureCoreStorageTypeInstance(context: ContextWithDriver)
 				    MERGE (ti)-[:CONTAINS]->(tir)
 				    MERGE (tir)-[:DESCRIBED_BY]->(metadata:TypeInstanceResourceVersionMetadata)
 				    MERGE (tir)-[:SPECIFIED_BY]->(spec)
+				    SET ti.createdAt = CASE WHEN ti.createdAt IS NOT NULL THEN ti.createdAt ELSE datetime() END
 
 				    RETURN ti
 					`, {value});