fix: add block_height to status and prometheus (#250)

src/api/routes/status.ts

@@ -24,6 +24,8 @@ export const StatusRoutes: FastifyPluginCallback<
     },
     async (request, reply) => {
       const result = await fastify.db.sqlTransaction(async sql => {
+        const block_height = await fastify.db.getChainTipBlockHeight();
+
         const smartContracts: Record<string, number> = {};
         const contractCounts = await fastify.db.getSmartContractCounts();
         for (const row of contractCounts) {
@@ -45,6 +47,9 @@ export const StatusRoutes: FastifyPluginCallback<
         return {
           server_version: `token-metadata-api ${SERVER_VERSION.tag} (${SERVER_VERSION.branch}:${SERVER_VERSION.commit})`,
           status: 'ready',
+          chain_tip: {
+            block_height,
+          },
           tokens: tokenCounts.length ? tokens : undefined,
           token_contracts: contractCounts.length ? smartContracts : undefined,
           job_queue: jobCounts.length ? queue : undefined,

src/api/schemas.ts

@@ -310,6 +310,9 @@ export const ApiStatusResponse = Type.Object(
   {
     server_version: Type.String({ examples: ['token-metadata-api v0.0.1 (master:a1b2c3)'] }),
     status: Type.String({ examples: ['ready'] }),
+    chain_tip: Type.Object({
+      block_height: Type.Integer({ examples: [163541] }),
+    }),
     tokens: Type.Optional(
       Type.Object(
         {

src/pg/chainhook/chainhook-pg-store.ts

@@ -113,6 +113,10 @@ export class ChainhookPgStore extends BasePgStoreModule {
     );
   }
 
+  async updateChainTipBlockHeight(blockHeight: number): Promise<void> {
+    await this.sql`UPDATE chain_tip SET block_height = GREATEST(${blockHeight}, block_height)`;
+  }
+
   private async getLastIngestedBlockHeight(): Promise<number> {
     const result = await this.sql<{ block_height: number }[]>`SELECT block_height FROM chain_tip`;
     return result[0].block_height;
@@ -383,10 +387,6 @@ export class ChainhookPgStore extends BasePgStoreModule {
     throw new ContractNotFoundError();
   }
 
-  private async updateChainTipBlockHeight(blockHeight: number): Promise<void> {
-    await this.sql`UPDATE chain_tip SET block_height = GREATEST(${blockHeight}, block_height)`;
-  }
-
   private async enqueueDynamicTokensDueForRefresh(): Promise<void> {
     const interval = ENV.METADATA_DYNAMIC_TOKEN_REFRESH_INTERVAL.toString();
     await this.sql`

src/token-processor/token-processor-metrics.ts

@@ -2,6 +2,7 @@ import * as prom from 'prom-client';
 import { PgStore } from '../pg/pg-store';
 
 export class TokenProcessorMetrics {
+  readonly token_metadata_block_height: prom.Gauge;
   /** Job count divided by status */
   readonly token_metadata_job_count: prom.Gauge;
   /** Smart contract count divided by SIP number */
@@ -14,6 +15,14 @@ export class TokenProcessorMetrics {
   }
 
   private constructor(db: PgStore) {
+    this.token_metadata_block_height = new prom.Gauge({
+      name: `token_metadata_block_height`,
+      help: 'The most recent Bitcoin block height ingested by the API',
+      async collect() {
+        const height = await db.getChainTipBlockHeight();
+        this.set(height);
+      },
+    });
     this.token_metadata_job_count = new prom.Gauge({
       name: `token_metadata_job_count`,
       help: 'Job count divided by status',

tests/api/status.test.ts

@@ -30,6 +30,9 @@ describe('Status routes', () => {
     expect(json).toStrictEqual({
       server_version: 'token-metadata-api v0.0.1 (test:123456)',
       status: 'ready',
+      chain_tip: {
+        block_height: 1,
+      },
     });
     const noVersionResponse = await fastify.inject({ method: 'GET', url: '/metadata/' });
     expect(response.statusCode).toEqual(noVersionResponse.statusCode);
@@ -43,12 +46,16 @@ describe('Status routes', () => {
       DbSipNumber.sip009,
       1n
     );
+    await db.chainhook.updateChainTipBlockHeight(100);
 
     const response = await fastify.inject({ method: 'GET', url: '/metadata/v1/' });
     const json = response.json();
     expect(json).toStrictEqual({
       server_version: 'token-metadata-api v0.0.1 (test:123456)',
       status: 'ready',
+      chain_tip: {
+        block_height: 100,
+      },
       job_queue: {
         pending: 2,
       },