feat(network): ensure protoc version >=3.15 (#1991)

crates/papyrus_network/build.rs

@@ -1,13 +1,37 @@
-use std::io::Result;
+use std::env;
+use std::io::{Error, ErrorKind, Result};
+use std::process::Command;
 
 fn main() -> Result<()> {
     println!("Building");
-    prost_build::compile_protos(
-        &[
-            "src/protobuf_messages/proto/p2p/proto/header.proto",
-            "src/protobuf_messages/proto/p2p/proto/state.proto",
-        ],
-        &["src/protobuf_messages/proto/"],
-    )?;
-    Ok(())
+    let protoc = env::var("PROTOC").unwrap_or("protoc".to_string());
+
+    let protoc_version = String::from_utf8_lossy(
+        &Command::new(protoc).arg("--version").output().expect("Protoc is not installed.").stdout,
+    )
+    .to_string();
+
+    let parts: Vec<&str> = protoc_version.split_whitespace().collect();
+    let protoc_version_str = parts.get(1).expect("Failed to determine protoc version");
+    let mut protoc_version_parts = protoc_version_str
+        .split('.')
+        .map(|part| part.parse::<u32>().expect("Error parsing protoc version"));
+    let major = protoc_version_parts.next().expect("Protoc version did not have a major number");
+    let minor = protoc_version_parts.next().unwrap_or_default();
+
+    if major < 3 || (major == 3 && minor < 15) {
+        Err(Error::new(
+            ErrorKind::Other,
+            "protoc version is too old. version 3.15.x or greater is needed.",
+        ))
+    } else {
+        prost_build::compile_protos(
+            &[
+                "src/protobuf_messages/proto/p2p/proto/header.proto",
+                "src/protobuf_messages/proto/p2p/proto/state.proto",
+            ],
+            &["src/protobuf_messages/proto/"],
+        )?;
+        Ok(())
+    }
 }