Initial repository setup and core files added

Add configuration, documentation, code of conduct, contributing guide, license, and README files. Set up .gitignore, coverage config, GitHub issue templates, pull request template, and initial source code, scripts, and tests for DeepLX optimized for Cloudflare Workers.

tests/lib/errorHandler.test.ts

@@ -0,0 +1,141 @@
+/**
+ * Tests for error handling functionality
+ */
+
+import { createErrorResponse } from "../../src/lib/errorHandler";
+
+describe("Error Handler Module", () => {
+  describe("createErrorResponse", () => {
+    it("should handle generic errors", () => {
+      const error = new Error("Generic error message");
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBeGreaterThanOrEqual(400);
+      expect(result.response.data).toBeNull();
+      expect(result.httpStatus).toBeGreaterThanOrEqual(400);
+    });
+
+    it("should handle errors with status codes", () => {
+      const error = new Error("Bad request");
+      (error as any).status = 400;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(400);
+      expect(result.httpStatus).toBe(400);
+    });
+
+    it("should handle errors with code property", () => {
+      const error = new Error("Rate limit exceeded");
+      (error as any).code = 429;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(429);
+      expect(result.httpStatus).toBe(429);
+    });
+
+    it("should handle timeout errors", () => {
+      const error = new Error("Request timeout after 30 seconds");
+      (error as any).status = 408;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(408);
+      expect(result.httpStatus).toBe(408);
+    });
+
+    it("should handle network errors", () => {
+      const error = new Error("Network error");
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBeGreaterThanOrEqual(500);
+      expect(result.httpStatus).toBeGreaterThanOrEqual(500);
+    });
+
+    it("should handle DeepL API errors", () => {
+      const error = new Error(
+        "DeepL API error: Invalid request format (Code: 1156049)"
+      );
+      (error as any).code = 1156049;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(1156049);
+    });
+
+    it("should include context information", () => {
+      const error = new Error("Test error");
+      const context = {
+        endpoint: "/translate",
+        clientIP: "192.168.1.1",
+      };
+
+      const result = createErrorResponse(error, context);
+
+      expect(result.response.code).toBeGreaterThanOrEqual(400);
+      expect(result.response.data).toBeNull();
+    });
+
+    it("should handle non-Error objects", () => {
+      const result1 = createErrorResponse("String error");
+      expect(result1.response.code).toBeGreaterThanOrEqual(400);
+
+      const result2 = createErrorResponse({ message: "Object error" });
+      expect(result2.response.code).toBeGreaterThanOrEqual(400);
+
+      const result3 = createErrorResponse(null);
+      expect(result3.response.code).toBeGreaterThanOrEqual(400);
+    });
+
+    it("should handle rate limiting errors specifically", () => {
+      const error = new Error("Rate limit exceeded");
+      (error as any).code = 429;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(429);
+      expect(result.httpStatus).toBe(429);
+    });
+
+    it("should handle server errors", () => {
+      const error = new Error("Internal server error");
+      (error as any).status = 500;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(500);
+      expect(result.httpStatus).toBe(500);
+    });
+
+    it("should handle authentication errors", () => {
+      const error = new Error("Unauthorized");
+      (error as any).status = 401;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(401);
+      expect(result.httpStatus).toBe(401);
+    });
+
+    it("should handle payload too large errors", () => {
+      const error = new Error("Request payload too large");
+      (error as any).status = 413;
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBe(413);
+      expect(result.httpStatus).toBe(413);
+    });
+
+    it("should provide default error when no message available", () => {
+      const error = new Error();
+
+      const result = createErrorResponse(error);
+
+      expect(result.response.code).toBeGreaterThanOrEqual(400);
+      expect(result.response.data).toBeNull();
+    });
+  });
+});