RAGFlow go API server (#13240)

# RAGFlow Go Implementation Plan 🚀

This repository tracks the progress of porting RAGFlow to Go. We'll
implement core features and provide performance comparisons between
Python and Go versions.

## Implementation Checklist

- [x] User Management APIs
- [x] Dataset Management Operations
- [x] Retrieval Test
- [x] Chat Management Operations
- [x] Infinity Go SDK

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>
Co-authored-by: Yingfeng Zhang <yingfeng.zhang@gmail.com>

internal/cpp/rag_analyzer_c_test.cpp

@@ -0,0 +1,120 @@
+#include <iostream>
+#include <thread>
+#include <vector>
+#include <cassert>
+#include <cstring>
+#include "rag_analyzer_c_api.h"
+
+// Test case 1: Single thread, loop 1000 times
+void test_single_thread() {
+    std::cout << "Test 1: Single thread, 1000 iterations..." << std::endl;
+    
+    // Create analyzer instance
+    RAGAnalyzerHandle handle = RAGAnalyzer_Create(".");
+    assert(handle != nullptr && "Failed to create RAGAnalyzer");
+    
+    // Load the analyzer
+    int result = RAGAnalyzer_Load(handle);
+    if (result != 0) {
+        printf("Failed to load RAGAnalyzer: %d\n", result);
+    }
+    assert(result == 0 && "Failed to load RAGAnalyzer");
+    
+    const char* input = "rag";
+    bool all_passed = true;
+    
+    for (int i = 0; i < 1000; ++i) {
+        char* tokens = RAGAnalyzer_Tokenize(handle, input);
+        
+        if (tokens == nullptr || strlen(tokens) == 0) {
+            std::cerr << "Iteration " << i << ": Failed - returned empty or null string" << std::endl;
+            all_passed = false;
+        }
+        
+        // Free the returned string
+        if (tokens != nullptr) {
+            free(tokens);
+        }
+    }
+    
+    // Destroy analyzer instance
+    RAGAnalyzer_Destroy(handle);
+    
+    if (all_passed) {
+        std::cout << "Test 1: PASSED" << std::endl;
+    } else {
+        std::cout << "Test 1: FAILED" << std::endl;
+        exit(1);
+    }
+}
+
+// Test case 2: 16 threads, each loop 1000 times
+void test_multi_thread() {
+    std::cout << "Test 2: 32 threads, each 100000 iterations..." << std::endl;
+    
+    // Create analyzer instance (shared across threads)
+    RAGAnalyzerHandle handle = RAGAnalyzer_Create(".");
+    assert(handle != nullptr && "Failed to create RAGAnalyzer");
+    
+    // Load the analyzer
+    int result = RAGAnalyzer_Load(handle);
+    assert(result == 0 && "Failed to load RAGAnalyzer");
+    
+    const char* input = "rag";
+    const int num_threads = 32;
+    const int iterations_per_thread = 100000;
+    
+    std::vector<std::thread> threads;
+    std::vector<bool> thread_results(num_threads, true);
+    
+    for (int t = 0; t < num_threads; ++t) {
+        threads.emplace_back([&, t]() {
+            for (int i = 0; i < iterations_per_thread; ++i) {
+                char* tokens = RAGAnalyzer_Tokenize(handle, input);
+                
+                if (tokens == nullptr || strlen(tokens) == 0) {
+                    std::cerr << "Thread " << t << " Iteration " << i << ": Failed - returned empty or null string" << std::endl;
+                    thread_results[t] = false;
+                }
+                
+                // Free the returned string
+                if (tokens != nullptr) {
+                    free(tokens);
+                }
+            }
+        });
+    }
+    
+    // Wait for all threads to complete
+    for (auto& t : threads) {
+        t.join();
+    }
+    
+    // Destroy analyzer instance
+    RAGAnalyzer_Destroy(handle);
+    
+    bool all_passed = true;
+    for (int t = 0; t < num_threads; ++t) {
+        if (!thread_results[t]) {
+            all_passed = false;
+            break;
+        }
+    }
+    
+    if (all_passed) {
+        std::cout << "Test 2: PASSED" << std::endl;
+    } else {
+        std::cout << "Test 2: FAILED" << std::endl;
+        exit(1);
+    }
+}
+
+int main() {
+    std::cout << "=== RAGAnalyzer C API Test ===" << std::endl;
+    
+    test_single_thread();
+    // test_multi_thread();
+    
+    std::cout << "=== All tests PASSED ===" << std::endl;
+    return 0;
+}