Separate api for getting tenant gitManager. (#14290)

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## Description
A lot of consumers of TenantManager.getTenant() across the Server
codebase need only the GitManager property of the returned ITenant
object. Constructing a tenant GitManager instance requires only the
tenant keys (which are already being cached), while retrieving the
tenant data involves a call to tenant DB. This change refactors out the
tenant GitManager instance construction into a separate API and switches
the callers of TenantManager.getTenant() that consume only the
GitManager property to this new API, so that they do not unnecessarily
incur a tenant DB call.

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server/routerlicious/packages/lambdas/src/deli/lambdaFactory.ts

@@ -86,8 +86,7 @@ export class DeliLambdaFactory extends EventEmitter implements IPartitionLambdaF
         let document: IDocument;
 
         try {
-            const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-            gitManager = tenant.gitManager;
+            gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
             // Lookup the last sequence number stored
             // TODO - is this storage specific to the orderer in place? Or can I generalize the output context?

server/routerlicious/packages/lambdas/src/scribe/lambdaFactory.ts

@@ -84,8 +84,7 @@ export class ScribeLambdaFactory extends EventEmitter implements IPartitionLambd
             LumberEventName.ScribeSessionResult, this.serviceConfiguration);
 
         try {
-            const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-            gitManager = tenant.gitManager;
+            gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
             summaryReader = new SummaryReader(tenantId, documentId, gitManager, this.enableWholeSummaryUpload);
             [latestSummary, document] = await Promise.all([

server/routerlicious/packages/lambdas/src/test/scribe/lambda.spec.ts

@@ -63,8 +63,7 @@ describe("Routerlicious", () => {
                 testKafka = new TestKafka();
                 testProducer = testKafka.createProducer();
                 testTenantManager = new TestTenantManager();
-                const tenant = await testTenantManager.getTenant(testTenantId, testDocumentId);
-                testGitManager = tenant.gitManager as GitManager;
+                testGitManager = (await testTenantManager.getTenantGitManager(testTenantId, testDocumentId)) as GitManager;
                 const createTreeEntry: ICreateTreeEntry[] = [];
                 const requestBody: ICreateTreeParams = {
                     tree: createTreeEntry,

server/routerlicious/packages/routerlicious-base/src/alfred/services/deltaService.ts

@@ -79,8 +79,7 @@ export class DeltaService implements IDeltaService {
         documentId: string,
         from?: number,
         to?: number) {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         const existingRef = await gitManager.getRef(encodeURIComponent(documentId));
         if (!existingRef) {

server/routerlicious/packages/services-core/src/tenant.ts

@@ -86,6 +86,11 @@ export interface ITenantManager {
      */
     getTenant(tenantId: string, documentId: string): Promise<ITenant>;
 
+    /**
+     * Retrieves GitManager instance for the given tenant
+     */
+    getTenantGitManager(tenantId: string, documentId: string): Promise<IGitManager>;
+
     /**
      * Verifies that the given auth token is valid. A rejected promise indicates an invalid token.
      */

server/routerlicious/packages/services-shared/src/storage.ts

@@ -121,8 +121,7 @@ export class DocumentStorage implements IDocumentStorage {
         values: [string, ICommittedProposal][],
         enableDiscovery: boolean = false,
     ): Promise<IDocumentDetails> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         const lumberjackProperties = {
             [BaseTelemetryProperties.tenantId]: tenantId,
@@ -258,30 +257,28 @@ export class DocumentStorage implements IDocumentStorage {
     }
 
     public async getVersions(tenantId: string, documentId: string, count: number): Promise<ICommitDetails[]> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         return gitManager.getCommits(documentId, count);
     }
 
     public async getVersion(tenantId: string, documentId: string, sha: string): Promise<ICommit> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         return gitManager.getCommit(sha);
     }
 
     public async getFullTree(tenantId: string, documentId: string): Promise<{ cache: IGitCache; code: string; }> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const versions = await tenant.gitManager.getCommits(documentId, 1);
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
+        const versions = await gitManager.getCommits(documentId, 1);
         if (versions.length === 0) {
             return {
                 cache: { blobs: [], commits: [], refs: { [documentId]: (null as unknown) as string }, trees: [] },
                 code: (null as unknown) as string,
             };
         }
 
-        const fullTree = await tenant.gitManager.getFullTree(versions[0].sha);
+        const fullTree = await gitManager.getFullTree(versions[0].sha);
 
         let code: string = (null as unknown) as string;
         if (fullTree.quorumValues) {
@@ -373,8 +370,7 @@ export class DocumentStorage implements IDocumentStorage {
     }
 
     private async readFromSummary(tenantId: string, documentId: string): Promise<boolean> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
         const existingRef = await gitManager.getRef(encodeURIComponent(documentId));
         if (existingRef) {
             // Fetch ops from logTail and insert into deltas collection.

server/routerlicious/packages/services/src/tenant.ts

@@ -9,6 +9,7 @@ import {
     ICredentials,
     BasicRestWrapper,
     getAuthorizationTokenFromCredentials,
+    IGitManager,
 } from "@fluidframework/server-services-client";
 import { generateToken, getCorrelationId } from "@fluidframework/server-services-utils";
 import * as core from "@fluidframework/server-services-core";
@@ -19,7 +20,7 @@ export class Tenant implements core.ITenant {
         return this.config.id;
     }
 
-    public get gitManager(): GitManager {
+    public get gitManager(): IGitManager {
         return this.manager;
     }
 
@@ -31,7 +32,7 @@ export class Tenant implements core.ITenant {
         return this.config.orderer;
     }
 
-    constructor(private readonly config: core.ITenantConfig, private readonly manager: GitManager) {
+    constructor(private readonly config: core.ITenantConfig, private readonly manager: IGitManager) {
     }
 }
 
@@ -53,10 +54,18 @@ export class TenantManager implements core.ITenantManager {
 
     public async getTenant(tenantId: string, documentId: string, includeDisabledTenant = false): Promise<core.ITenant> {
         const restWrapper = new BasicRestWrapper();
-        const [details, key] = await Promise.all([
+        const [details, gitManager] = await Promise.all([
             restWrapper.get<core.ITenantConfig>(`${this.endpoint}/api/tenants/${tenantId}`,
             { includeDisabledTenant }),
-            this.getKey(tenantId, includeDisabledTenant)]);
+            this.getTenantGitManager(tenantId, documentId, includeDisabledTenant)]);
+
+        const tenant = new Tenant(details, gitManager);
+
+        return tenant;
+    }
+
+    public async getTenantGitManager(tenantId: string, documentId: string, includeDisabledTenant = false): Promise<IGitManager> {
+        const key = await this.getKey(tenantId, includeDisabledTenant);
 
         const defaultQueryString = {
             token: fromUtf8ToBase64(`${tenantId}`),
@@ -88,9 +97,8 @@ export class TenantManager implements core.ITenantManager {
             false,
             tenantRestWrapper);
         const gitManager = new GitManager(historian);
-        const tenant = new Tenant(details, gitManager);
 
-        return tenant;
+        return gitManager;
     }
 
     public async verifyToken(tenantId: string, token: string): Promise<void> {

server/routerlicious/packages/test-utils/src/testDocumentStorage.ts

@@ -65,8 +65,7 @@ export class TestDocumentStorage implements IDocumentStorage {
         values: [string, ICommittedProposal][],
         enableDiscovery: boolean = false,
     ): Promise<IDocumentDetails> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         const blobsShaCache = new Set<string>();
         const handle = await writeSummaryTree(gitManager, summary, blobsShaCache, undefined);
@@ -180,15 +179,13 @@ export class TestDocumentStorage implements IDocumentStorage {
     }
 
     public async getVersions(tenantId: string, documentId: string, count: number): Promise<ICommitDetails[]> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         return gitManager.getCommits(documentId, count);
     }
 
     public async getVersion(tenantId: string, documentId: string, sha: string): Promise<ICommit> {
-        const tenant = await this.tenantManager.getTenant(tenantId, documentId);
-        const gitManager = tenant.gitManager;
+        const gitManager = await this.tenantManager.getTenantGitManager(tenantId, documentId);
 
         return gitManager.getCommit(sha);
     }

server/routerlicious/packages/test-utils/src/testTenantManager.ts

@@ -71,6 +71,10 @@ export class TestTenantManager implements ITenantManager {
         return this.tenant;
     }
 
+    public async getTenantGitManager(tenantId: string, documentId: string): Promise<GitManager> {
+        return this.tenant.gitManager;
+    }
+
     public async getKey(tenantId: string): Promise<string> {
         return "test";
     }