add ancestorTags field and resolver on the UserTag schema

schema.graphql

@@ -1907,6 +1907,9 @@ type UserTag {
   """A field to get the mongodb object id identifier for this UserTag."""
   _id: ID!
 
+  """A field to traverse the ancestor tags of this UserTag."""
+  ancestorTags: [UserTag]
+
   """
   A connection field to traverse a list of UserTag this UserTag is a
   parent to.

src/resolvers/UserTag/ancestorTags.ts

@@ -0,0 +1,44 @@
+import type {
+  InterfaceOrganizationTagUser} from "../../models";
+import {
+  OrganizationTagUser,
+} from "../../models";
+import type { UserTagResolvers } from "../../types/generatedGraphQLTypes";
+
+/**
+ * Resolver function for the `ancestorTags` field of an `OrganizationTagUser`.
+ *
+ * This function retrieves the ancestor tags of a specific organization user tag by recursively finding
+ * each parent tag until the root tag (where parentTagId is null) is reached. It then reverses the order,
+ * appends the current tag at the end, and returns the final array of tags.
+ *
+ * @param parent - The parent object representing the user tag. It contains information about the tag, including its ID and parentTagId.
+ * @returns A promise that resolves to the ordered array of ancestor tag documents found in the database.
+ */
+export const ancestorTags: UserTagResolvers["ancestorTags"] = async (
+  parent,
+) => {
+  // Initialize an array to collect the ancestor tags
+  const ancestorTags: InterfaceOrganizationTagUser[] = [];
+
+  // Start with the current parentTagId
+  let currentParentId = parent.parentTagId;
+
+  // Traverse up the hierarchy to find all ancestorTags
+  while (currentParentId) {
+    const tag = await OrganizationTagUser.findById(currentParentId).lean();
+
+    if (!tag) break;
+
+    // Add the found tag to the ancestorTags array
+    ancestorTags.push(tag);
+
+    // Move up to the next parent
+    currentParentId = tag.parentTagId;
+  }
+
+  // Reverse the ancestorTags to have the root tag first, then append the current tag
+  ancestorTags.reverse();
+
+  return ancestorTags;
+};

src/resolvers/UserTag/index.ts

@@ -2,13 +2,15 @@ import type { UserTagResolvers } from "../../types/generatedGraphQLTypes";
 import { childTags } from "./childTags";
 import { organization } from "./organization";
 import { parentTag } from "./parentTag";
+import { ancestorTags } from "./ancestorTags";
 import { usersAssignedTo } from "./usersAssignedTo";
 import { usersToAssignTo } from "./usersToAssignTo";
 
 export const UserTag: UserTagResolvers = {
   childTags,
   organization,
   parentTag,
+  ancestorTags,
   usersAssignedTo,
   usersToAssignTo,
 };

src/typeDefs/types.ts

@@ -663,6 +663,10 @@ export const types = gql`
     """
     parentTag: UserTag
     """
+    A field to traverse the ancestor tags of this UserTag.
+    """
+    ancestorTags: [UserTag]
+    """
     A connection field to traverse a list of UserTag this UserTag is a
     parent to.
     """

src/types/generatedGraphQLTypes.ts

@@ -2995,6 +2995,8 @@ export type UserTag = {
   __typename?: 'UserTag';
   /** A field to get the mongodb object id identifier for this UserTag. */
   _id: Scalars['ID']['output'];
+  /** A field to traverse the ancestor tags of this UserTag. */
+  ancestorTags?: Maybe<Array<Maybe<UserTag>>>;
   /**
    * A connection field to traverse a list of UserTag this UserTag is a
    * parent to.
@@ -4699,6 +4701,7 @@ export type UserPhoneResolvers<ContextType = any, ParentType extends ResolversPa
 
 export type UserTagResolvers<ContextType = any, ParentType extends ResolversParentTypes['UserTag'] = ResolversParentTypes['UserTag']> = {
   _id?: Resolver<ResolversTypes['ID'], ParentType, ContextType>;
+  ancestorTags?: Resolver<Maybe<Array<Maybe<ResolversTypes['UserTag']>>>, ParentType, ContextType>;
   childTags?: Resolver<Maybe<ResolversTypes['UserTagsConnection']>, ParentType, ContextType, Partial<UserTagChildTagsArgs>>;
   name?: Resolver<ResolversTypes['String'], ParentType, ContextType>;
   organization?: Resolver<Maybe<ResolversTypes['Organization']>, ParentType, ContextType>;

tests/resolvers/UserTag/ancestorTags.spec.ts

@@ -0,0 +1,45 @@
+import "dotenv/config";
+import type mongoose from "mongoose";
+import { afterAll, beforeAll, describe, expect, it } from "vitest";
+import type {
+  InterfaceOrganizationTagUser} from "../../../src/models";
+import {
+  OrganizationTagUser,
+} from "../../../src/models";
+import { ancestorTags as ancestorTagsResolver } from "../../../src/resolvers/UserTag/ancestorTags";
+import { connect, disconnect } from "../../helpers/db";
+import type { TestUserTagType } from "../../helpers/tags";
+import { createTwoLevelTagsWithOrg } from "../../helpers/tags";
+import type { TestOrganizationType } from "../../helpers/userAndOrg";
+
+let MONGOOSE_INSTANCE: typeof mongoose;
+let testRootTag: TestUserTagType,
+  testSubTagLevel1: TestUserTagType,
+  testSubTagLevel2: TestUserTagType;
+let testOrganization: TestOrganizationType;
+
+beforeAll(async () => {
+  MONGOOSE_INSTANCE = await connect();
+  [, testOrganization, [testRootTag, testSubTagLevel1]] =
+    await createTwoLevelTagsWithOrg();
+
+  testSubTagLevel2 = await OrganizationTagUser.create({
+    name: "testSubTagLevel2",
+    parentTagId: testSubTagLevel1?._id,
+    organizationId: testOrganization?._id,
+  });
+});
+
+afterAll(async () => {
+  await disconnect(MONGOOSE_INSTANCE);
+});
+
+describe("resolvers -> Tag -> ancestorTags", () => {
+  it(`returns the correct ancestorTags array`, async () => {
+    const parent = testSubTagLevel2 as InterfaceOrganizationTagUser;
+
+    const payload = await ancestorTagsResolver?.(parent, {}, {});
+
+    expect(payload).toEqual([testRootTag, testSubTagLevel1]);
+  });
+});