Add option to format output as json

Cargo.lock

@@ -220,6 +220,7 @@ dependencies = [
  "log",
  "pnet",
  "serde",
+ "serde_json",
  "serde_yaml",
  "tokio",
 ]
@@ -730,6 +731,18 @@ dependencies = [
  "syn 2.0.72",
 ]
 
+[[package]]
+name = "serde_json"
+version = "1.0.127"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8043c06d9f82bd7271361ed64f415fe5e12a77fdb52e573e7f06a516dea329ad"
+dependencies = [
+ "itoa",
+ "memchr",
+ "ryu",
+ "serde",
+]
+
 [[package]]
 name = "serde_yaml"
 version = "0.9.34+deprecated"

Cargo.toml

@@ -13,5 +13,6 @@ ipnetwork = "0.20.0"
 log = "0.4.22"
 pnet = "0.35.0"
 serde = { version = "1.0.209", features = ["derive"] }
+serde_json = "1.0.127"
 serde_yaml = "0.9.34"
 tokio = { version = "1.39.3", features = ["macros", "net", "rt-multi-thread"] }

src/main.rs

@@ -38,6 +38,9 @@ const DHCP_RELAY_AGENT_AND_SERVER_PORT: u16 = 547;
 struct Cli {
     /// Network interface name used for DHCPv6
     interface: String,
+    /// Format output as json
+    #[arg(long)]
+    json: bool,
 }
 
 #[derive(Serialize)]
@@ -154,9 +157,17 @@ async fn main() -> Result<()>{
     };
 
     let message_map = message_to_map(&response_msg);
-    let message_map_yaml = serde_yaml::to_string(&message_map)
-        .context("Unable to format message to yaml")?;
-    println!("{}", message_map_yaml);
+
+    if cli.json {
+        let message_map_json = serde_json::to_string(&message_map)
+            .context("Unable to format message to json")?;
+        println!("{}", message_map_json);
+    }
+    else {
+        let message_map_yaml = serde_yaml::to_string(&message_map)
+            .context("Unable to format message to yaml")?;
+        println!("{}", message_map_yaml);
+    }
 
     Ok(())
 }