feat: 优化环境变量占位符替换逻辑，环境变量不存在时返回空字符串而非错误

Author: ZR233

ostool/src/run/uboot.rs

@@ -268,9 +268,11 @@ impl Runner {
 
     async fn run(&mut self) -> anyhow::Result<()> {
         let res = self._run().await;
-        if let Some(cmd) = self.config.board_power_off_cmd.clone() {
+        if let Some(ref cmd) = self.config.board_power_off_cmd
+            && !cmd.trim().is_empty()
+        {
             info!("Executing board power off command: {}", cmd);
-            let _ = self.ctx.shell_run_cmd(&cmd);
+            let _ = self.ctx.shell_run_cmd(cmd);
             info!("Board powered off");
         }
         res
@@ -285,21 +287,19 @@ impl Runner {
         info!("Starting U-Boot runner...");
 
         info!("kernel from: {}", kernel.display());
-        if self.config.net.is_some() {
-            tftp::run_tftp_server(&self.ctx)?;
-        }
 
         let ip_string = self.detect_tftp_ip();
 
+        if let Some(ip) = ip_string.as_ref() {
+            info!("TFTP server IP: {}", ip);
+            tftp::run_tftp_server(&self.ctx)?;
+        }
+
         info!(
             "Opening serial port: {} @ {}",
             self.config.serial, self.baud_rate
         );
 
-        if let Some(ref ip) = ip_string {
-            info!("TFTP server IP: {}", ip);
-        }
-
         let rx = serialport::new(&self.config.serial, self.baud_rate as _)
             .timeout(Duration::from_millis(200))
             .open()
@@ -314,7 +314,9 @@ impl Runner {
             Ok(uboot)
         });
 
-        if let Some(cmd) = self.config.board_reset_cmd.clone() {
+        if let Some(cmd) = self.config.board_reset_cmd.clone()
+            && !cmd.trim().is_empty()
+        {
             info!("Executing board reset command: {}", cmd);
             self.ctx.shell_run_cmd(&cmd)?;
         }
@@ -487,8 +489,8 @@ impl Runner {
             }
         }
 
-        if ip_string.is_empty() {
-            panic!("Cannot detect IP address for interface: {}", net.interface);
+        if ip_string.trim().is_empty() {
+            return None;
         }
 
         info!("TFTP : {}", ip_string);

ostool/src/utils.rs

@@ -168,15 +168,12 @@ pub fn replace_env_placeholders(input: &str) -> anyhow::Result<String> {
             if found_closing_brace && placeholder.starts_with("env:") {
                 let env_var_name = &placeholder[4..]; // 跳过 "env:"
 
-                // 获取环境变量值，如果不存在则返回错误
+                // 获取环境变量值，如果不存在则替换为空字符串
                 match env::var(env_var_name) {
                     Ok(value) => result.push_str(&value),
                     Err(_) => {
-                        return Err(anyhow::anyhow!(
-                            "环境变量 '{}' 未设置，无法替换占位符 ${{env:{}}}",
-                            env_var_name,
-                            env_var_name
-                        ));
+                        // 环境变量不存在时替换为空字符串，不返回错误
+                        result.push_str("");
                     }
                 }
             } else {
@@ -220,10 +217,10 @@ mod tests {
             "/home/test:/usr/local/bin"
         );
 
-        // 测试不存在的环境变量
+        // 测试不存在的环境变量 - 应该返回空字符串而不是错误
         let result = replace_env_placeholders("${env:NON_EXISTENT}");
-        assert!(result.is_err());
-        assert!(result.unwrap_err().to_string().contains("未设置"));
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), "");
 
         // 测试混合内容
         assert_eq!(
@@ -276,10 +273,10 @@ mod tests {
         assert_eq!(replace_env_placeholders("${env:").unwrap(), "${env:");
         assert_eq!(replace_env_placeholders("${env:VAR").unwrap(), "${env:VAR");
 
-        // 测试空的env变量名
+        // 测试空的env变量名 - 应该返回空字符串而不是错误
         let result = replace_env_placeholders("${env:}");
-        assert!(result.is_err());
-        assert!(result.unwrap_err().to_string().contains("未设置"));
+        assert!(result.is_ok());
+        assert_eq!(result.unwrap(), "");
 
         // 测试只包含$的字符串
         assert_eq!(replace_env_placeholders("$").unwrap(), "$");