fix: broken database option when using replication, changes introduce…

…d by #4753 (#4826)

src/connection/Connection.ts

@@ -518,10 +518,26 @@ export class Connection {
         const migrations = connectionMetadataBuilder.buildMigrations(this.options.migrations || []);
         ObjectUtils.assign(this, { migrations: migrations });
 
-        this.driver.database = <string> this.options.database;
+        this.driver.database = this.getDatabaseName();
 
         // validate all created entity metadatas to make sure user created entities are valid and correct
         entityMetadataValidator.validateMany(this.entityMetadatas.filter(metadata => metadata.tableType !== "view"), this.driver);
     }
 
+    // This database name property is nested for replication configs.
+    protected getDatabaseName(): string {
+    const options = this.options;
+    switch (options.type) {
+        case "mysql" :
+        case "mariadb" :
+        case "postgres":
+        case "cockroachdb":
+        case "mssql":
+        case "oracle":
+            return (options.replication ? options.replication.master.database : options.database) as string;
+        default:
+            return options.database as string;
+    }
+}
+
 }

test/github-issues/4753/entity/User.ts

@@ -0,0 +1,10 @@
+import { Entity, Column, PrimaryGeneratedColumn } from "../../../../src";
+
+@Entity()
+export class User {
+    @PrimaryGeneratedColumn()
+    id: number;
+
+    @Column()
+    name: string;
+}

test/github-issues/4753/issue-4753.ts

@@ -0,0 +1,33 @@
+import { getConnectionManager } from "../../../src";
+import { Connection } from "../../../src/connection/Connection";
+import { closeTestingConnections } from "../../utils/test-utils";
+import { User } from "./entity/User";
+
+describe("github issues > #4753 MySQL Replication Config broken", () => {
+    let connections: Connection[] = [];
+    after(() => closeTestingConnections(connections));
+
+    it("should connect without error when using replication", async () => {
+        const connection = getConnectionManager().create({
+            type: "mysql",
+            replication: {
+                master: {
+                    username: "test",
+                    password: "test",
+                    database: "test"
+                },
+                slaves: [
+                    {
+                        username: "test",
+                        password: "test",
+                        database: "test"
+                    }
+                ]
+            },
+            entities: [User]
+        });
+        connections.push(connection);
+        await connection.connect();
+        connection.isConnected.should.be.true;
+    });
+});