fix: update returned Job with API-determined location in getMetadata (#900)

Author: laljikanjareeya

src/job.ts

@@ -126,10 +126,7 @@ class Job extends Operation {
     options?: QueryResultsOptions
   ) => ResourceStream<RowMetadata>;
   constructor(bigQuery: BigQuery, id: string, options?: JobOptions) {
-    let location;
-    if (options && options.location) {
-      location = options.location;
-    }
+    let location: string;
 
     const methods = {
       /**
@@ -222,7 +219,11 @@ class Job extends Operation {
        */
       getMetadata: {
         reqOpts: {
-          qs: {location},
+          qs: {
+            get location() {
+              return location;
+            },
+          },
         },
       },
     };
@@ -234,6 +235,15 @@ class Job extends Operation {
       methods,
     });
 
+    Object.defineProperty(this, 'location', {
+      get() {
+        return location;
+      },
+      set(_location) {
+        location = _location;
+      },
+    });
+
     this.bigQuery = bigQuery;
 
     if (options && options.location) {

test/job.ts

@@ -150,6 +150,18 @@ describe('BigQuery/Job', () => {
         },
       });
     });
+
+    it('should update the location after initializing job object', () => {
+      const job = new Job(BIGQUERY, JOB_ID);
+      job.location = LOCATION;
+      const calledWith = job.calledWith_[0];
+
+      assert.deepStrictEqual(calledWith.methods.getMetadata, {
+        reqOpts: {
+          qs: {location: LOCATION},
+        },
+      });
+    });
   });
 
   describe('cancel', () => {