Merge pull request #33 from Azure/enewman/fix-empty-override-file

Enewman/fix empty override file

Author: EMaher

src/lib/config-loader.ts

@@ -32,7 +32,7 @@ function assertStringArray(value: unknown, fieldName: string): string[] {
 export async function loadFilterConfig(filePath: string): Promise<FilterConfig | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
+    const parsed = (yaml.load(content) ?? {}) as Record<string, unknown>;
 
     // Validate structure — each field must be an array of strings
     const config: FilterConfig = {};
@@ -104,13 +104,10 @@ export async function loadFilterConfig(filePath: string): Promise<FilterConfig |
 export async function loadOverrideConfig(filePath: string): Promise<OverrideConfig | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
-    
-    // Return as-is; validation will happen during publish when applied
-    const config = parsed as OverrideConfig;
+    const parsed = (yaml.load(content) ?? {}) as OverrideConfig;
 
     logger.debug(`Loaded override config from ${filePath}`);
-    return config;
+    return parsed;
   } catch (error) {
     if ((error as NodeJS.ErrnoException).code === 'ENOENT') {
       logger.debug(`Override config file not found: ${filePath}`);
@@ -127,7 +124,7 @@ export async function loadOverrideConfig(filePath: string): Promise<OverrideConf
 export async function loadOTelConfig(filePath: string): Promise<Record<string, unknown> | undefined> {
   try {
     const content = await fs.readFile(filePath, 'utf-8');
-    const parsed = yaml.load(content) as Record<string, unknown>;
+    const parsed = (yaml.load(content) ?? {}) as Record<string, unknown>;
 
     logger.debug(`Loaded OTel config from ${filePath}`);
     return parsed;

src/lib/logger.ts

@@ -56,13 +56,22 @@ function isSensitiveKey(key: string): boolean {
 
 /**
  * Recursively sanitize a value, replacing sensitive fields with '***'.
- * Handles objects, arrays, and inline bearer tokens in strings.
+ * Handles objects, arrays, inline bearer tokens in strings, and Error objects.
  */
 function sanitize(value: unknown): unknown {
   if (typeof value === 'string') {
     // Redact inline bearer tokens (e.g. "Bearer eyJ...")
     return value.replace(/Bearer\s+[A-Za-z0-9\-._~+/]+=*/gi, 'Bearer ***');
   }
+  if (value instanceof Error) {
+    // Convert Error objects to a serializable form
+    return {
+      name: sanitize(value.name),
+      message: sanitize(value.message),
+      stack: value.stack === undefined ? undefined : sanitize(value.stack),
+      ...(value.cause ? { cause: sanitize(value.cause) } : {}),
+    };
+  }
   if (Array.isArray(value)) {
     return value.map((item) => sanitize(item));
   }

tests/unit/lib/config-loader.test.ts

@@ -49,6 +49,24 @@ tagNames:
       expect(config).toBeDefined();
     });
 
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadFilterConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only comments', async () => {
+      const filePath = path.join(tmpDir, 'comments.yaml');
+      await fs.writeFile(filePath, '# This is a comment\n# Another comment', 'utf-8');
+
+      const config = await loadFilterConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
     it('should throw for invalid type (non-array field)', async () => {
       const content = `
 apiNames: "not-an-array"
@@ -123,6 +141,24 @@ backends:
       const config = await loadOverrideConfig(path.join(tmpDir, 'nonexistent.yaml'));
       expect(config).toBeUndefined();
     });
+
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadOverrideConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only comments', async () => {
+      const filePath = path.join(tmpDir, 'comments.yaml');
+      await fs.writeFile(filePath, '# Override config\n# TODO: add overrides', 'utf-8');
+
+      const config = await loadOverrideConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
   });
 
   describe('loadOTelConfig', () => {
@@ -148,5 +184,23 @@ service:
       const config = await loadOTelConfig(path.join(tmpDir, 'nonexistent.yaml'));
       expect(config).toBeUndefined();
     });
+
+    it('should handle completely empty file', async () => {
+      const filePath = path.join(tmpDir, 'blank.yaml');
+      await fs.writeFile(filePath, '', 'utf-8');
+
+      const config = await loadOTelConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
+
+    it('should handle file with only whitespace', async () => {
+      const filePath = path.join(tmpDir, 'whitespace.yaml');
+      await fs.writeFile(filePath, '   \n  \n  ', 'utf-8');
+
+      const config = await loadOTelConfig(filePath);
+      expect(config).toBeDefined();
+      expect(config).toEqual({});
+    });
   });
 });

tests/unit/lib/logger.test.ts

@@ -146,6 +146,27 @@ describe('Logger', () => {
       expect(output).toContain('test');
       expect(output).toContain('42');
     });
+
+    it('should serialize Error objects with message and stack', () => {
+      const error = new Error('Something went wrong');
+      loggerInstance.error('Error occurred:', error);
+      const output = stderrSpy.mock.calls[0]![0] as string;
+      expect(output).toContain('Something went wrong');
+      expect(output).toContain('"name":"Error"');
+      expect(output).toContain('"message":"Something went wrong"');
+      // Stack trace should be present (not testing exact format)
+      expect(output).toContain('"stack"');
+    });
+
+    it('should serialize Error objects with cause', () => {
+      const innerError = new Error('Inner error');
+      const outerError = new Error('Outer error', { cause: innerError });
+      loggerInstance.error('Nested error:', outerError);
+      const output = stderrSpy.mock.calls[0]![0] as string;
+      expect(output).toContain('Outer error');
+      expect(output).toContain('Inner error');
+      expect(output).toContain('"cause"');
+    });
   });
 
   describe('non-ASCII punctuation normalization', () => {