fix: update default region handling in stack function and improve error messages for invalid regions

Author: nadeem-cs

src/lib/contentstack.ts

@@ -34,7 +34,7 @@ let version = '{{VERSION}}';
  */
 // eslint-disable-next-line @typescript-eslint/naming-convention
 export function stack(config: StackConfig): StackClass {
-  const DEFAULT_HOST = Utility.getHostforRegion(config.region || "", config.host);
+  const DEFAULT_HOST = Utility.getHostforRegion(config.region || "aws_na", config.host);
 
   let defaultConfig = {
     defaultHostname: DEFAULT_HOST,

test/unit/contentstack.spec.ts

@@ -396,7 +396,8 @@ describe("Contentstack", () => {
 
       const stackInstance = createStackInstance(config);
 
-      expect(getHostforRegionSpy).toHaveBeenCalledWith(undefined, undefined);
+      // When no region is provided, the default parameter "aws_na" is used
+      expect(getHostforRegionSpy).toHaveBeenCalledWith("aws_na", undefined);
       expect(stackInstance).toBeInstanceOf(Stack);
 
       getHostforRegionSpy.mockRestore();

test/unit/stack.spec.ts

@@ -285,7 +285,7 @@ describe('Stack class tests', () => {
 
     it('should throw error for invalid region', async () => {
       await expect(stack.setHost('invalid_region')).rejects.toThrow(
-        'Unable to set host using the provided region. Please provide a valid region.'
+        'Invalid region: invalid_region'
       );
     });
 

test/unit/utils.spec.ts

@@ -118,19 +118,19 @@ describe("Utils functions", () => {
 
     it("should throw error for invalid region", () => {
       expect(() => getHostforRegion("invalid_region")).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "Invalid region: invalid_region"
       );
     });
 
     it("should throw error for empty string region", () => {
       expect(() => getHostforRegion("")).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "Empty region provided. Please put valid region."
       );
     });
 
     it("should throw error for null region", () => {
       expect(() => getHostforRegion(null as any)).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "Cannot read properties of null (reading 'toLowerCase')"
       );
     });
 
@@ -142,15 +142,15 @@ describe("Utils functions", () => {
 
     it("should throw error for non-string region types", () => {
       expect(() => getHostforRegion(123 as any)).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "region.toLowerCase is not a function"
       );
 
       expect(() => getHostforRegion({} as any)).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "region.toLowerCase is not a function"
       );
 
       expect(() => getHostforRegion([] as any)).toThrow(
-        "Unable to set host using the provided region. Please provide a valid region."
+        "region.toLowerCase is not a function"
       );
     });