Factor out handler, allow strings as port numbers to simplify Jinja2 templates

netpod/src/netpod.rs

@@ -220,8 +220,11 @@ pub struct ChannelArchiver {
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct Node {
     pub host: String,
+    // TODO for `listen` and the ports, would be great to allow a default on Cluster level.
     pub listen: String,
+    #[serde(deserialize_with = "port_from_any")]
     pub port: u16,
+    #[serde(deserialize_with = "port_from_any")]
     pub port_raw: u16,
     pub cache_base_path: PathBuf,
     pub sf_databuffer: Option<SfDatabuffer>,
@@ -229,6 +232,58 @@ pub struct Node {
     pub channel_archiver: Option<ChannelArchiver>,
 }
 
+struct Visit1 {}
+
+impl<'de> serde::de::Visitor<'de> for Visit1 {
+    type Value = u16;
+
+    fn expecting(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        write!(fmt, "a tcp port number, in numeric or string form.")
+    }
+
+    fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        if v > u16::MAX as u64 {
+            Err(serde::de::Error::invalid_type(
+                serde::de::Unexpected::Unsigned(v),
+                &self,
+            ))
+        } else {
+            self.visit_i64(v as i64)
+        }
+    }
+
+    fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        if v < 1 || v > u16::MAX as i64 {
+            Err(serde::de::Error::invalid_type(serde::de::Unexpected::Signed(v), &self))
+        } else {
+            Ok(v as u16)
+        }
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: serde::de::Error,
+    {
+        match v.parse::<u16>() {
+            Err(_) => Err(serde::de::Error::invalid_type(serde::de::Unexpected::Str(v), &self)),
+            Ok(v) => Ok(v),
+        }
+    }
+}
+
+fn port_from_any<'de, D>(de: D) -> Result<u16, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    de.deserialize_any(Visit1 {})
+}
+
 impl Node {
     // TODO needed? Could `sf_databuffer` be None?
     pub fn dummy() -> Self {