feat: add Rust FFI integration for last 5 blocks fetching

Author: sntntn

goCode/goApp/main.go

@@ -6,10 +6,14 @@ package main
 
 // fetch_transactions je Rust funkcija koja vraca podatke o transakcijama iz poslednjeg bloka
 char* fetch_transactions(const char* rpc_url);
+
+// fetch_last_5_blocks je Rust funkcija koja vraca podatke o transakciji maksimalnog potrosenog gasa u poslednjih 5 blokova
+char* fetch_last_5_blocks(const char* rpc_url);
 */
 import "C"
 
 import (
+	"encoding/json"
 	"fmt"
 	"unsafe"
 
@@ -21,28 +25,49 @@ import (
 
 func main() {
 
-	rpcURL, recipientAddress, privateKeyHex := config.LoadEnv()
+	rpcTestnetURL, rpcMainnetURL, recipientAddress, privateKeyHex := config.LoadEnv()
 
-	blockNumber := rpc.GetLatestBlock(rpcURL)
+	blockNumber := rpc.GetLatestBlock(rpcTestnetURL)
 	fmt.Println(blockNumber)
 	fmt.Println()
 
 	fakeBalance := utilis.EthToHex(100) // 100 ETH
-	transaction.SetFakeBalance(rpcURL, recipientAddress, fakeBalance)
+	transaction.SetFakeBalance(rpcTestnetURL, recipientAddress, fakeBalance)
 
 	sendEth := 1
-	transaction.SendTransaction(rpcURL, recipientAddress, int64(sendEth), privateKeyHex)
+	transaction.SendTransaction(rpcTestnetURL, recipientAddress, int64(sendEth), privateKeyHex)
 
-	//---------------------------
+	// === Deo koji zove Rust FFI za transakcije ===
 	fmt.Println()
 
-	cRpcURL := C.CString(rpcURL)
-	defer C.free(unsafe.Pointer(cRpcURL))
+	cRpcTestnetURL := C.CString(rpcTestnetURL)
+	defer C.free(unsafe.Pointer(cRpcTestnetURL))
 
-	result := C.fetch_transactions(cRpcURL)
+	result := C.fetch_transactions(cRpcTestnetURL)
 	defer C.free(unsafe.Pointer(result))
 
 	goResult := C.GoString(result)
 	fmt.Println("Rust FFI: Podaci o transakcijama iz poslednjeg bloka:\n", goResult)
 
+	// === Deo koji zove Rust FFI za 5 blokova ===
+	fmt.Println()
+
+	cRpcMainnetURL := C.CString(rpcMainnetURL)
+	defer C.free(unsafe.Pointer(cRpcMainnetURL))
+
+	resultArray := C.fetch_last_5_blocks(cRpcMainnetURL)
+	defer C.free(unsafe.Pointer(resultArray))
+	goArray := C.GoString(resultArray)
+
+	var summaries []rpc.TxSummary
+	err := json.Unmarshal([]byte(goArray), &summaries)
+	if err != nil {
+		fmt.Println("Greska pri parsiranju JSON-a iz Rust-a:", err)
+		return
+	}
+
+	for _, s := range summaries {
+		fmt.Printf("Blok %s | TX %s | Gas %d | %.3f%% u bloku\n",
+			s.BlockNumber, s.TxHash, s.GasUsed, s.PercentInBlock)
+	}
 }

goCode/internal/config/config.go

@@ -7,7 +7,7 @@ import (
 	"github.com/joho/godotenv"
 )
 
-func LoadEnv() (string, string, string) {
+func LoadEnv() (string, string, string, string) {
 	err := godotenv.Load("../.env")
 	if err != nil {
 		log.Fatal("Greska pri ucitavanju .env fajla")
@@ -18,6 +18,11 @@ func LoadEnv() (string, string, string) {
 		log.Fatal("Nedostaje RPC_TESTNET_URL u .env fajlu")
 	}
 
+	rpcMainnetURL := os.Getenv("RPC_MAINNET_URL")
+	if rpcTestnetURL == "" {
+		log.Fatal("Nedostaje RPC_TESTNET_URL u .env fajlu")
+	}
+
 	recipient := os.Getenv("RECIPIENT_ADDRESS")
 	if recipient == "" {
 		log.Fatal("Nedostaje RECIPIENT_ADDRESS u .env fajlu")
@@ -28,5 +33,5 @@ func LoadEnv() (string, string, string) {
 		log.Fatal("Nedostaje PRIVATE_KEY u .env fajlu")
 	}
 
-	return rpcTestnetURL, recipient, privateKeyHex
+	return rpcTestnetURL, rpcMainnetURL, recipient, privateKeyHex
 }

goCode/internal/rpc/types.go

@@ -30,3 +30,10 @@ type Transaction struct {
 	Gas      string `json:"gas"`
 	GasPrice string `json:"gasPrice"`
 }
+
+type TxSummary struct {
+	BlockNumber    uint64  `json:"block_number"`
+	TxHash         string  `json:"tx_hash"`
+	GasUsed        uint64  `json:"gas_used"`
+	PercentInBlock float64 `json:"percent_in_block"`
+}

rustCode/src/lib.rs

@@ -2,9 +2,10 @@ pub mod models;
 pub mod rpc;
 pub mod utils;
 
-use crate::rpc::fetch::fetch_latest_block;
+use crate::rpc::fetch::{fetch_latest_block, fetch_last_5_blocks_and_receipts};
 use std::ffi::CString;
 use std::os::raw::c_char;
+use crate::utils::hex_to_u64;
 
 #[no_mangle]
 pub extern "C" fn fetch_transactions(rpc_url: *const c_char) -> *mut c_char {
@@ -34,3 +35,19 @@ pub extern "C" fn fetch_transactions(rpc_url: *const c_char) -> *mut c_char {
     // Vracanje C stringa koji Go moze koristiti
     c_str_result.into_raw()
 }
+
+#[no_mangle]
+pub extern "C" fn fetch_last_5_blocks(rpc_url: *const c_char) -> *mut c_char {
+    let c_rpc = unsafe { std::ffi::CStr::from_ptr(rpc_url) };
+    let rpc_url_str = c_rpc.to_str().unwrap();
+
+    let runtime = tokio::runtime::Runtime::new().unwrap();
+    let latest_block = runtime.block_on(fetch_latest_block(rpc_url_str, true));
+    let latest_block_number = hex_to_u64(&latest_block.number);
+
+    let summaries = runtime.block_on(fetch_last_5_blocks_and_receipts(rpc_url_str.to_string(), latest_block_number));
+
+    let json_str = serde_json::to_string(&summaries).unwrap();
+    let c_str_result = CString::new(json_str).unwrap();
+    c_str_result.into_raw()
+}

rustCode/src/models/mod.rs

@@ -44,6 +44,7 @@ pub struct TransactionReceipt {
     pub cumulative_gas_used: String,
 }
 
+#[derive(serde::Serialize)]
 pub struct TxSummary {
     pub block_number: String,
     pub tx_hash: String,