Add max active postgres requests

src/config.ts

@@ -76,7 +76,8 @@ addDefaults(config, {
         port: 5432,
         max: 10,
         idleTimeoutMillis: 10000,
-        maxTries: 3
+        maxTries: 3,
+        maxActiveRequests: -1
     },
     postgresReadOnly: {
         enabled: false,

src/databases/Postgres.ts

@@ -3,7 +3,7 @@ import { IDatabase, QueryOption, QueryType } from "./IDatabase";
 import { Client, Pool, QueryResult, types } from "pg";
 
 import fs from "fs";
-import { CustomPostgresConfig, CustomPostgresReadOnlyConfig } from "../types/config.model";
+import { CustomPostgresReadOnlyConfig, CustomWritePostgresConfig } from "../types/config.model";
 import { timeoutPomise, PromiseWithState, savePromiseState, nextFulfilment } from "../utils/promise";
 
 // return numeric (pg_type oid=1700) as float
@@ -22,7 +22,7 @@ export interface DatabaseConfig {
     fileNamePrefix: string,
     readOnly: boolean,
     createDbIfNotExists: boolean,
-    postgres: CustomPostgresConfig,
+    postgres: CustomWritePostgresConfig,
     postgresReadOnly: CustomPostgresReadOnlyConfig
 }
 
@@ -105,6 +105,10 @@ export class Postgres implements IDatabase {
 
         Logger.debug(`prepare (postgres): type: ${type}, query: ${query}, params: ${params}`);
 
+        if (this.activePostgresRequests > this.config.postgres.maxActiveRequests) {
+            throw new Error("Too many active postgres requests");
+        }
+
         const pendingQueries: PromiseWithState<QueryResult<any>>[] = [];
         let tries = 0;
         let lastPool: Pool = null;

src/types/config.model.ts

@@ -19,6 +19,10 @@ export interface CustomPostgresConfig extends PoolConfig {
     maxTries: number;
 }
 
+export interface CustomWritePostgresConfig extends CustomPostgresConfig {
+    maxActiveRequests: number;
+}
+
 export interface CustomPostgresReadOnlyConfig extends CustomPostgresConfig {
     weight: number;
     readTimeout: number;
@@ -71,7 +75,7 @@ export interface SBSConfig {
     redisRead?: RedisReadOnlyConfig;
     redisRateLimit: boolean;
     maxRewardTimePerSegmentInSeconds?: number;
-    postgres?: CustomPostgresConfig;
+    postgres?: CustomWritePostgresConfig;
     postgresReadOnly?: CustomPostgresReadOnlyConfig;
     dumpDatabase?: DumpDatabase;
     diskCacheURL: string;