Fix duplicate postgres database connection issue (#2961)

* refactor pg-promise to connect as a singleton

* update import path for db functions

* fix other imports

* couple more spots that needed the change

* fix typing

* fix tests after merge

* remove logs

* iron out merge issues

* remove unneeded export

containers/ecr-viewer/src/app/api/conditions/service.ts

@@ -1,15 +1,15 @@
 import { NextResponse } from "next/server";
-import pgPromise from "pg-promise";
-import { database } from "../services/postgres_db";
-import { get_pool } from "../services/sqlserver_db";
 import sql from "mssql";
+import { get_pool } from "../services/sqlserver_db";
+import { getDB } from "../services/postgres_db";
 
 /**
  * Retrieves all unique conditions from the ecr_rr_conditions table in the PostgreSQL database.
  * @returns A promise resolving to a NextResponse object.
  * @throws An error if the connection to the PostgreSQL database fails.
  */
 export const get_conditions_postgres = async () => {
+  const { database, pgPromise } = getDB();
   const { ParameterizedQuery: PQ } = pgPromise;
 
   try {
@@ -19,8 +19,9 @@ export const get_conditions_postgres = async () => {
       });
 
       const conditions = await t.any(getConditions);
+
       return NextResponse.json(
-        conditions.map((c) => c.condition),
+        conditions.map((c: any) => c.condition),
         { status: 200 },
       );
     });

containers/ecr-viewer/src/app/api/fhir-data/fhir-data-service.ts

@@ -1,15 +1,16 @@
 import { NextRequest, NextResponse } from "next/server";
-import pgPromise from "pg-promise";
 import { GetObjectCommand } from "@aws-sdk/client-s3";
 import {
   BlobClient,
   BlobDownloadResponseParsed,
   BlobServiceClient,
 } from "@azure/storage-blob";
 import { loadYamlConfig, streamToJson } from "../utils";
-import { database } from "../services/postgres_db";
+import { getDB } from "../services/postgres_db";
 import { s3Client } from "../services/s3Client";
 
+const { database, pgPromise } = getDB();
+
 /**
  * Retrieves FHIR data from PostgreSQL database based on eCR ID.
  * @param request - The NextRequest object containing the request information.

containers/ecr-viewer/src/app/api/save-fhir-data/save-fhir-data-service.ts

@@ -1,7 +1,6 @@
 import { BlobServiceClient } from "@azure/storage-blob";
 import { NextResponse } from "next/server";
-import pgPromise from "pg-promise";
-import { database, db_url } from "../services/postgres_db";
+import { getDB } from "../services/postgres_db";
 import { PutObjectCommand, PutObjectCommandOutput } from "@aws-sdk/client-s3";
 import { Bundle } from "fhir/r4";
 import { S3_SOURCE, AZURE_SOURCE, POSTGRES_SOURCE } from "@/app/api/utils";
@@ -11,6 +10,8 @@ import { BundleExtendedMetadata, BundleMetadata } from "./types";
 import { s3Client } from "../services/s3Client";
 import { get_pool } from "../services/sqlserver_db";
 
+const { database, pgPromise } = getDB();
+
 /**
  * Saves a FHIR bundle to a postgres database.
  * @async
@@ -38,7 +39,7 @@ export const saveToPostgres = async (fhirBundle: Bundle, ecrId: string) => {
     console.error("Error inserting data to database:", error);
     return NextResponse.json(
       {
-        message: `Failed to insert data to database. ${error.message} url: ${db_url}`,
+        message: `Failed to insert data to database. ${error.message}`,
       },
       { status: 500 },
     );

containers/ecr-viewer/src/app/api/services/postgres_db.ts

@@ -1,4 +1,41 @@
 import pgp from "pg-promise";
 
-export const db_url = process.env.DATABASE_URL || "";
-export const database = pgp()(db_url);
+/**
+ * Global scope singleton creator for pgPromise
+ * @async
+ * @function createSingleton
+ * @param name A name for your singleton
+ * @param create Anonymous function containing what you want singleton-ized
+ * @returns A singleton of the provided object
+ */
+const createSingleton = <T>(name: string, create: () => T): T => {
+  const s = Symbol.for(name);
+  let scope = (global as any)[s];
+  if (!scope) {
+    scope = { ...create() };
+    (global as any)[s] = scope;
+  }
+  return scope;
+};
+
+const pgPromise = pgp();
+const db_url = process.env.DATABASE_URL || "";
+
+interface IDatabaseScope {
+  database: pgp.IDatabase<any>;
+  pgPromise: pgp.IMain;
+}
+
+/**
+ * Provides access to pgPromise DB singleton
+ * @function getDB
+ * @returns A singleton of the pgPromise DB connection
+ */
+export const getDB = (): IDatabaseScope => {
+  return createSingleton<IDatabaseScope>("my-app-database-space", () => {
+    return {
+      database: pgPromise(db_url),
+      pgPromise,
+    };
+  });
+};

containers/ecr-viewer/src/app/api/tests/conditions.service.test.ts

@@ -2,7 +2,7 @@ import {
   get_conditions_postgres,
   get_conditions_sqlserver,
 } from "@/app/api/conditions/service";
-import { database } from "@/app/api/services/postgres_db";
+import { getDB } from "../services/postgres_db";
 import { NextResponse } from "next/server";
 
 // Mock dependencies
@@ -12,10 +12,9 @@ jest.mock("mssql", () => ({
   Request: jest.fn(),
 }));
 
+// Mock getDB and NextResponse
 jest.mock("../services/postgres_db", () => ({
-  database: {
-    tx: jest.fn(),
-  },
+  getDB: jest.fn(),
 }));
 
 jest.mock("next/server", () => ({
@@ -25,6 +24,22 @@ jest.mock("next/server", () => ({
 }));
 
 describe("get_conditions_postgres", () => {
+  const mockDatabase = {
+    tx: jest.fn(),
+  };
+
+  beforeEach(() => {
+    // Mock getDB to return the mock database
+    (getDB as jest.Mock).mockReturnValue({
+      database: mockDatabase,
+      pgPromise: {
+        ParameterizedQuery: jest.fn().mockImplementation(({ text }: any) => ({
+          text,
+        })),
+      },
+    });
+  });
+
   afterEach(() => {
     jest.clearAllMocks();
   });
@@ -35,17 +50,15 @@ describe("get_conditions_postgres", () => {
       { condition: "condition2" },
     ];
 
-    (database.tx as jest.Mock).mockImplementation(async (callback: any) => {
+    mockDatabase.tx.mockImplementation(async (callback: any) => {
       const t = {
         any: jest.fn().mockResolvedValue(mockConditions),
       };
       return callback(t);
     });
 
     (NextResponse.json as jest.Mock).mockImplementation(
-      (data: any, options: any) => {
-        return { data, options };
-      },
+      (data: any, options: any) => ({ data, options }),
     );
 
     const response = await get_conditions_postgres();
@@ -54,23 +67,24 @@ describe("get_conditions_postgres", () => {
       data: ["condition1", "condition2"],
       options: { status: 200 },
     });
+
     expect(NextResponse.json).toHaveBeenCalledWith(
       ["condition1", "condition2"],
       { status: 200 },
     );
+    expect(mockDatabase.tx).toHaveBeenCalledTimes(1);
   });
 
-  it("should handle error when database query fails", async () => {
+  it("should return an error response when database query fails", async () => {
     const errorMessage = "Database error";
 
-    (database.tx as jest.Mock).mockImplementation(async () => {
+    // Mock database.tx to throw an error
+    mockDatabase.tx.mockImplementation(async () => {
       throw new Error(errorMessage);
     });
 
     (NextResponse.json as jest.Mock).mockImplementation(
-      (data: any, options: any) => {
-        return { data, options };
-      },
+      (data: any, options: any) => ({ data, options }),
     );
 
     const response = await get_conditions_postgres();
@@ -79,10 +93,12 @@ describe("get_conditions_postgres", () => {
       data: { message: errorMessage },
       options: { status: 500 },
     });
+
     expect(NextResponse.json).toHaveBeenCalledWith(
       { message: errorMessage },
       { status: 500 },
     );
+    expect(mockDatabase.tx).toHaveBeenCalledTimes(1);
   });
 });
 

containers/ecr-viewer/src/app/services/listEcrDataService.ts

@@ -1,11 +1,12 @@
-import { database } from "@/app/api/services/postgres_db";
 import {
   convertUTCToLocalString,
   formatDate,
   formatDateTime,
 } from "@/app/services/formatService";
-import pgPromise from "pg-promise";
 import { get_pool } from "../api/services/sqlserver_db";
+import { getDB } from "../api/services/postgres_db";
+
+const { database, pgPromise } = getDB();
 
 export interface CoreMetadataModel {
   eicr_id: string;

containers/ecr-viewer/src/app/tests/listEcrDataService.test.tsx

@@ -8,21 +8,23 @@ import {
   generateSearchStatement,
   generateWhereStatementPostgres,
   getTotalEcrCount,
-  listEcrData,
   processCoreMetadata,
+  listEcrData,
 } from "../services/listEcrDataService";
+import { getDB } from "../api/services/postgres_db";
 import {
   convertUTCToLocalString,
   formatDate,
   formatDateTime,
 } from "../services/formatService";
-import { database } from "../api/services/postgres_db";
 import { get_pool } from "../api/services/sqlserver_db";
 
 jest.mock("../api/services/sqlserver_db", () => ({
   get_pool: jest.fn(),
 }));
 
+const { database } = getDB();
+
 describe("listEcrDataService", () => {
   describe("process Metadata", () => {
     it("should return an empty array when responseBody is empty", () => {