add switch module

1 files changed, 71 insertions, 0 deletions

diff --git a/src/modules/switch.rs b/src/modules/switch.rs
new file mode 100644
index 0000000..bbb9e98
--- /dev/null
+++ b/src/modules/switch.rs
@@ -0,0 +1,71 @@
+use super::{Node, NodeContext, NodeKind, NodeRequest, NodeResponse};
+use crate::{config::DynNode, error::ServiceError};
+use anyhow::Result;
+use futures::Future;
+use headers::{HeaderMapExt, Upgrade};
+use hyper::Method;
+use serde::Deserialize;
+use std::{pin::Pin, sync::Arc};
+
+pub struct SwitchKind;
+
+#[derive(Deserialize)]
+pub struct Switch {
+    condition: Condition,
+    case_true: DynNode,
+    case_false: DynNode,
+}
+
+impl NodeKind for SwitchKind {
+    fn name(&self) -> &'static str {
+        "switch"
+    }
+    fn instanciate(&self, config: serde_yaml::Value) -> Result<Arc<dyn Node>> {
+        Ok(Arc::new(serde_yaml::from_value::<Switch>(config)?))
+    }
+}
+
+impl Node for Switch {
+    fn handle<'a>(
+        &'a self,
+        context: &'a mut NodeContext,
+        request: NodeRequest,
+    ) -> Pin<Box<dyn Future<Output = Result<NodeResponse, ServiceError>> + Send + Sync + 'a>> {
+        Box::pin(async move {
+            let cond = self.condition.test(&request);
+            if cond {
+                &self.case_true
+            } else {
+                &self.case_false
+            }
+            .handle(context, request)
+            .await
+        })
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(rename_all = "snake_case")]
+enum Condition {
+    IsWebsocketUpgrade,
+    IsPost,
+    IsGet,
+    HasHeader(String),
+    PathStartsWith(String),
+    PathIs(String),
+}
+
+impl Condition {
+    pub fn test(&self, req: &NodeRequest) -> bool {
+        match self {
+            Condition::IsWebsocketUpgrade => {
+                req.headers().typed_get::<Upgrade>() == Some(Upgrade::websocket())
+            }
+            Condition::HasHeader(name) => req.headers().contains_key(name),
+            Condition::PathStartsWith(path_prefix) => req.uri().path().starts_with(path_prefix),
+            Condition::PathIs(path) => req.uri().path() == path,
+            Condition::IsPost => req.method() == Method::POST,
+            Condition::IsGet => req.method() == Method::GET,
+        }
+    }
+}