[dont merge] support both apigw and alb events as http::{Request,Response} (cargo features)

lambda-http/Cargo.toml

@@ -31,3 +31,7 @@ serde_urlencoded = "0.5"
 log = "^0.4"
 simple_logger = "^1"
 
+[features]
+default = ['apigw', 'alb']
+apigw = []
+alb = []

lambda-http/src/ext.rs

@@ -251,6 +251,7 @@ mod tests {
             foo: String,
             baz: usize,
         }
+
         let lambda_request: LambdaRequest<'_> = LambdaRequest {
             path: "/foo".into(),
             headers,

lambda-http/src/lib.rs

@@ -100,9 +100,17 @@ where
     let mut func = f;
     lambda::start(
         |req: LambdaRequest<'_>, ctx: Context| {
-            let is_alb = req.request_context.is_alb();
-            func.run(req.into(), ctx)
-                .map(|resp| LambdaResponse::from_response(is_alb, resp.into_response()))
+            #[cfg(feature = "alb")]
+            {
+                let is_alb = req.request_context.is_alb();
+                func.run(req.into(), ctx)
+                    .map(|resp| LambdaResponse::from_response(is_alb, resp.into_response()))
+            }
+            #[cfg(not(feature = "alb"))]
+            {
+                func.run(req.into(), ctx)
+                    .map(|resp| LambdaResponse::from_response(false, resp.into_response()))
+            }
         },
         runtime,
     )

lambda-http/src/request.rs

@@ -44,10 +44,10 @@ pub(crate) struct LambdaRequest<'a> {
     /// the `lambda.multi_value_headers.enabled` target group setting turned on
     #[serde(default, deserialize_with = "nullable_default")]
     pub(crate) multi_value_query_string_parameters: StrMap,
-    /// ALB events do not have path parameters.
+    #[cfg(feature = "apigw")]
     #[serde(default, deserialize_with = "nullable_default")]
     pub(crate) path_parameters: StrMap,
-    /// ALB events do not have stage variables.
+    #[cfg(feature = "apigw")]
     #[serde(default, deserialize_with = "nullable_default")]
     pub(crate) stage_variables: StrMap,
     pub(crate) body: Option<Cow<'a, str>>,
@@ -58,6 +58,7 @@ pub(crate) struct LambdaRequest<'a> {
 
 /// Event request context as an enumeration of request contexts
 /// for both ALB and API Gateway http events
+#[cfg(all(feature = "apigw", feature = "alb"))]
 #[derive(Deserialize, Debug, Clone)]
 #[serde(untagged)]
 pub enum RequestContext {
@@ -81,6 +82,17 @@ pub enum RequestContext {
     Alb { elb: Elb },
 }
 
+/// ALB request context
+#[cfg(all(feature = "alb", not(all(feature = "apigw", feature = "alb"))))]
+#[derive(Default, Deserialize, Debug, Clone)]
+#[serde(rename_all = "camelCase")]
+pub struct RequestContext {
+    pub elb: Elb,
+}
+
+/// Api Gateway request context
+#[cfg(all(feature = "apigw", not(all(feature = "apigw", feature = "alb"))))]
+#[derive(Default, Deserialize, Debug, Clone)]
 impl Default for RequestContext {
     fn default() -> Self {
         RequestContext::ApiGateway {
@@ -97,16 +109,6 @@ impl Default for RequestContext {
     }
 }
 
-impl RequestContext {
-    /// Return true if this request context represents an ALB request
-    pub fn is_alb(&self) -> bool {
-        match self {
-            RequestContext::Alb { .. } => true,
-            _ => false,
-        }
-    }
-}
-
 /// Elastic load balancer context information
 #[derive(Deserialize, Debug, Default, Clone)]
 #[serde(rename_all = "camelCase")]
@@ -115,6 +117,41 @@ pub struct Elb {
     pub target_group_arn: String,
 }
 
+#[cfg(all(feature = "apigw", feature = "alb"))]
+impl Default for RequestContext {
+    fn default() -> Self {
+        RequestContext::ApiGateway {
+            account_id: Default::default(),
+            resource_id: Default::default(),
+            stage: Default::default(),
+            request_id: Default::default(),
+            resource_path: Default::default(),
+            http_method: Default::default(),
+            authorizer: Default::default(),
+            api_id: Default::default(),
+            identity: Default::default(),
+        }
+    }
+}
+
+#[cfg(feature = "alb")]
+impl RequestContext {
+    /// Return true if this request context represents an ALB request
+    pub fn is_alb(&self) -> bool {
+        #[cfg(all(feature = "apigw", feature = "alb"))]
+        {
+            match self {
+                RequestContext::Alb { .. } => true,
+                _ => false,
+            }
+        }
+        #[cfg(all(feature = "alb", not(all(feature = "apigw", feature = "alb"))))]
+        {
+            true
+        }
+    }
+}
+
 /// Identity assoicated with API Gateway request
 #[derive(Deserialize, Debug, Default, Clone)]
 #[serde(rename_all = "camelCase")]
@@ -336,6 +373,7 @@ mod tests {
     fn requests_convert() {
         let mut headers = HeaderMap::new();
         headers.insert("Host", "www.rust-lang.org".parse().unwrap());
+
         let lambda_request: LambdaRequest<'_> = LambdaRequest {
             path: "/foo".into(),
             headers,
@@ -348,6 +386,7 @@ mod tests {
         assert_eq!(expected.method(), actual.method());
     }
 
+    #[cfg(feature = "apigw")]
     #[test]
     fn deserializes_apigw_request_events() {
         // from the docs
@@ -357,6 +396,7 @@ mod tests {
         assert!(result.is_ok(), format!("event was not parsed as expected {:?}", result));
     }
 
+    #[cfg(feature = "alb")]
     #[test]
     fn deserialize_alb_request_events() {
         // from the docs
@@ -366,6 +406,7 @@ mod tests {
         assert!(result.is_ok(), format!("event was not parsed as expected {:?}", result));
     }
 
+    #[cfg(feature = "apigw")]
     #[test]
     fn deserializes_apigw_multi_value_request_events() {
         // from docs
@@ -388,6 +429,7 @@ mod tests {
         );
     }
 
+    #[cfg(feature = "alb")]
     #[test]
     fn deserializes_alb_multi_value_request_events() {
         // from docs

lambda-http/src/response.rs

@@ -19,6 +19,7 @@ pub(crate) struct LambdaResponse {
     pub status_code: u16,
     // ALB requires a statusDescription i.e. "200 OK" field but API Gateway returns an error
     // when one is provided. only populate this for ALB responses
+    #[cfg(feature = "alb")]
     #[serde(skip_serializing_if = "Option::is_none")]
     pub status_description: Option<String>,
     #[serde(serialize_with = "serialize_headers")]
@@ -36,6 +37,7 @@ impl Default for LambdaResponse {
     fn default() -> Self {
         Self {
             status_code: 200,
+            #[cfg(feature = "alb")]
             status_description: Default::default(),
             headers: Default::default(),
             multi_value_headers: Default::default(),
@@ -88,6 +90,7 @@ impl LambdaResponse {
         };
         Self {
             status_code: parts.status.as_u16(),
+            #[cfg(feature = "alb")]
             status_description: if is_alb {
                 Some(format!(
                     "{} {}",