Ensure thrift field IDs are within range (#302)

* Ensure thrift field IDs are within range

Signed-off-by: Vikrant Puppala <vikrant.puppala@databricks.com>

* fmt

Signed-off-by: Vikrant Puppala <vikrant.puppala@databricks.com>

---------

Signed-off-by: Vikrant Puppala <vikrant.puppala@databricks.com>

Author: vikrantpuppala

tests/unit/thrift-field-id-validation.test.ts

@@ -0,0 +1,86 @@
+import * as fs from 'fs';
+import * as path from 'path';
+import { expect } from 'chai';
+
+/**
+ * Validates that all Thrift-generated classes comply with field ID constraints.
+ *
+ * Field IDs in Thrift must stay below 3329 to avoid conflicts with reserved ranges and ensure
+ * compatibility with various Thrift implementations and protocols.
+ */
+describe('Thrift Field ID Validation', () => {
+  const MAX_ALLOWED_FIELD_ID = 3329;
+  const THRIFT_DIR = path.join(__dirname, '../../thrift');
+
+  it('should ensure all Thrift field IDs are within allowed range', () => {
+    const violations: string[] = [];
+
+    // Get all JavaScript files in the thrift directory
+    const thriftFiles = fs
+      .readdirSync(THRIFT_DIR)
+      .filter((file) => file.endsWith('.js'))
+      .map((file) => path.join(THRIFT_DIR, file));
+
+    expect(thriftFiles.length).to.be.greaterThan(0, 'No Thrift JavaScript files found');
+
+    for (const filePath of thriftFiles) {
+      const fileName = path.basename(filePath);
+      const fileContent = fs.readFileSync(filePath, 'utf8');
+
+      // Extract field IDs from both read and write functions
+      const fieldIds = extractFieldIds(fileContent);
+
+      for (const fieldId of fieldIds) {
+        if (fieldId >= MAX_ALLOWED_FIELD_ID) {
+          violations.push(
+            `${fileName}: Field ID ${fieldId} exceeds maximum allowed value of ${MAX_ALLOWED_FIELD_ID - 1}`,
+          );
+        }
+      }
+    }
+
+    if (violations.length > 0) {
+      const errorMessage = [
+        `Found Thrift field IDs that exceed the maximum allowed value of ${MAX_ALLOWED_FIELD_ID - 1}.`,
+        'This can cause compatibility issues and conflicts with reserved ID ranges.',
+        'Violations found:',
+        ...violations.map((v) => `  - ${v}`),
+      ].join('\n');
+
+      throw new Error(errorMessage);
+    }
+  });
+});
+
+/**
+ * Extracts all field IDs from the given Thrift JavaScript file content.
+ * Looks for field IDs in both read functions (case statements) and write functions (writeFieldBegin calls).
+ */
+function extractFieldIds(fileContent: string): number[] {
+  const fieldIds = new Set<number>();
+
+  // Pattern 1: Extract field IDs from case statements in read functions
+  // Example: case 1281:
+  const casePattern = /case\s+(\d+):/g;
+  let match;
+
+  while ((match = casePattern.exec(fileContent)) !== null) {
+    const fieldId = parseInt(match[1], 10);
+    if (!isNaN(fieldId)) {
+      fieldIds.add(fieldId);
+    }
+  }
+
+  // Pattern 2: Extract field IDs from writeFieldBegin calls in write functions
+  // Example: output.writeFieldBegin('errorDetailsJson', Thrift.Type.STRING, 1281);
+  const writeFieldPattern = /writeFieldBegin\([^,]+,\s*[^,]+,\s*(\d+)\)/g;
+
+  while ((match = writeFieldPattern.exec(fileContent)) !== null) {
+    const fieldId = parseInt(match[1], 10);
+    if (!isNaN(fieldId)) {
+      fieldIds.add(fieldId);
+    }
+  }
+
+  return Array.from(fieldIds).sort((a, b) => a - b);
+}