capnp and protoc versioning

veilid-core/build.rs

@@ -1,4 +1,102 @@
+use std::path::PathBuf;
+use std::process::{Command, Stdio};
+
+fn get_workspace_dir() -> PathBuf {
+    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .join("..")
+        .canonicalize()
+        .expect("want workspace dir")
+}
+fn get_desired_capnp_version_string() -> String {
+    std::fs::read_to_string(get_workspace_dir().join(".capnp_version"))
+        .expect("should find .capnp_version file")
+        .trim()
+        .to_owned()
+}
+
+fn get_capnp_version_string() -> String {
+    let output = Command::new("capnpc")
+        .arg("--version")
+        .stdout(Stdio::piped())
+        .output()
+        .expect("capnpc was not in the PATH");
+    let s = String::from_utf8(output.stdout)
+        .expect("'capnpc --version' output was not a valid string")
+        .trim()
+        .to_owned();
+
+    if !s.starts_with("Cap'n Proto version ") {
+        panic!("invalid capnpc version string: {}", s);
+    }
+    s[20..].to_owned()
+}
+
+fn get_desired_protoc_version_string() -> String {
+    std::fs::read_to_string(get_workspace_dir().join(".protoc_version"))
+        .expect("should find .protoc_version file")
+        .trim()
+        .to_owned()
+}
+
+fn get_protoc_version_string() -> String {
+    let output = Command::new("protoc")
+        .arg("--version")
+        .stdout(Stdio::piped())
+        .output()
+        .expect("protoc was not in the PATH");
+    let s = String::from_utf8(output.stdout)
+        .expect("'protoc --version' output was not a valid string")
+        .trim()
+        .to_owned();
+
+    if !s.starts_with("libprotoc ") {
+        panic!("invalid protoc version string: {}", s);
+    }
+    s[10..].to_owned()
+}
+
 fn main() {
+    let desired_capnp_version_string = get_desired_capnp_version_string();
+    let capnp_version_string = get_capnp_version_string();
+    let desired_protoc_version_string = get_desired_protoc_version_string();
+    let protoc_version_string = get_protoc_version_string();
+
+    // Check capnp version
+    let desired_capnp_major_version =
+        usize::from_str_radix(desired_capnp_version_string.split_once(".").unwrap().0, 10)
+            .expect("should be valid int");
+
+    if usize::from_str_radix(capnp_version_string.split_once(".").unwrap().0, 10)
+        .expect("should be valid int")
+        != desired_capnp_major_version
+    {
+        panic!(
+            "capnproto version should be major version 1, preferably {} but is {}",
+            desired_capnp_version_string, capnp_version_string
+        );
+    } else if capnp_version_string != desired_capnp_version_string {
+        println!(
+            "capnproto version may be untested: {}",
+            capnp_version_string
+        );
+    }
+
+    // Check protoc version
+    let desired_protoc_major_version =
+        usize::from_str_radix(desired_protoc_version_string.split_once(".").unwrap().0, 10)
+            .expect("should be valid int");
+    if usize::from_str_radix(protoc_version_string.split_once(".").unwrap().0, 10)
+        .expect("should be valid int")
+        < desired_protoc_major_version
+    {
+        panic!(
+            "capnproto version should be at least major version {} but is {}",
+            desired_protoc_major_version, protoc_version_string
+        );
+    } else if protoc_version_string != desired_protoc_version_string {
+        println!("protoc version may be untested: {}", protoc_version_string);
+    }
+
     ::capnpc::CompilerCommand::new()
         .file("proto/veilid.capnp")
         .run()