Implement custom deserializer for LambdaRequest

lambda-events/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "aws_lambda_events"
-version = "0.10.0"
+version = "0.11.0"
 description = "AWS Lambda event definitions"
 authors = [
   "Christian Legnitto <christian@legnitto.com>",

lambda-events/src/event/alb/mod.rs

@@ -9,6 +9,7 @@ use serde::{Deserialize, Serialize};
 /// `AlbTargetGroupRequest` contains data originating from the ALB Lambda target group integration
 #[derive(Clone, Debug, Default, Deserialize, PartialEq, Serialize)]
 #[serde(rename_all = "camelCase")]
+#[serde(deny_unknown_fields)]
 pub struct AlbTargetGroupRequest {
     #[serde(with = "http_method")]
     pub http_method: Method,

lambda-events/src/event/apigw/mod.rs

@@ -13,6 +13,7 @@ use std::collections::HashMap;
 /// `ApiGatewayProxyRequest` contains data coming from the API Gateway proxy
 #[derive(Clone, Debug, Default, Deserialize, PartialEq, Serialize)]
 #[serde(rename_all = "camelCase")]
+#[serde(deny_unknown_fields)]
 pub struct ApiGatewayProxyRequest<T1 = Value>
 where
     T1: DeserializeOwned,
@@ -118,12 +119,25 @@ where
 /// `ApiGatewayV2httpRequest` contains data coming from the new HTTP API Gateway
 #[derive(Clone, Debug, Default, Deserialize, PartialEq, Serialize)]
 #[serde(rename_all = "camelCase")]
+#[serde(deny_unknown_fields)]
 pub struct ApiGatewayV2httpRequest {
+    #[serde(default, rename = "type")]
+    pub kind: Option<String>,
+    #[serde(default)]
+    pub method_arn: Option<String>,
+    #[serde(with = "http_method", default = "default_http_method")]
+    pub http_method: Method,
+    #[serde(default)]
+    pub identity_source: Option<String>,
+    #[serde(default)]
+    pub authorization_token: Option<String>,
+    #[serde(default)]
+    pub resource: Option<String>,
     #[serde(default)]
     pub version: Option<String>,
     #[serde(default)]
     pub route_key: Option<String>,
-    #[serde(default)]
+    #[serde(default, alias = "path")]
     pub raw_path: Option<String>,
     #[serde(default)]
     pub raw_query_string: Option<String>,
@@ -319,6 +333,7 @@ pub struct ApiGatewayRequestIdentity {
 /// `ApiGatewayWebsocketProxyRequest` contains data coming from the API Gateway proxy
 #[derive(Clone, Debug, Default, Deserialize, PartialEq, Serialize)]
 #[serde(rename_all = "camelCase")]
+#[serde(deny_unknown_fields)]
 pub struct ApiGatewayWebsocketProxyRequest<T1 = Value, T2 = Value>
 where
     T1: DeserializeOwned,
@@ -747,6 +762,10 @@ pub struct IamPolicyStatement {
     pub resource: Vec<String>,
 }
 
+fn default_http_method() -> Method {
+    Method::GET
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -901,6 +920,8 @@ mod test {
         let output: String = serde_json::to_string(&parsed).unwrap();
         let reparsed: ApiGatewayV2httpRequest = serde_json::from_slice(output.as_bytes()).unwrap();
         assert_eq!(parsed, reparsed);
+        assert_eq!("REQUEST", parsed.kind.unwrap());
+        assert_eq!(Method::GET, parsed.http_method);
     }
 
     #[test]

lambda-events/src/fixtures/example-apigw-request.json

@@ -1,55 +1,95 @@
 {
 	"resource": "/{proxy+}",
-	  "path": "/hello/world",
-	  "httpMethod": "POST",
-	  "headers": {
-		  "Accept": "*/*",
-		  "Accept-Encoding": "gzip, deflate",
-		  "cache-control": "no-cache",
-		  "CloudFront-Forwarded-Proto": "https",
-		  "CloudFront-Is-Desktop-Viewer": "true",
-		  "CloudFront-Is-Mobile-Viewer": "false",
-		  "CloudFront-Is-SmartTV-Viewer": "false",
-		  "CloudFront-Is-Tablet-Viewer": "false",
-		  "CloudFront-Viewer-Country": "US",
-		  "Content-Type": "application/json",
-		  "headerName": "headerValue",
-		  "Host": "gy415nuibc.execute-api.us-east-1.amazonaws.com",
-		  "Postman-Token": "9f583ef0-ed83-4a38-aef3-eb9ce3f7a57f",
-		  "User-Agent": "PostmanRuntime/2.4.5",
-		  "Via": "1.1 d98420743a69852491bbdea73f7680bd.cloudfront.net (CloudFront)",
-		  "X-Amz-Cf-Id": "pn-PWIJc6thYnZm5P0NMgOUglL1DYtl0gdeJky8tqsg8iS_sgsKD1A==",
-		  "X-Forwarded-For": "54.240.196.186, 54.182.214.83",
-		  "X-Forwarded-Port": "443",
-		  "X-Forwarded-Proto": "https"
-    },
-    "multiValueHeaders": {
-        "Accept": ["*/*"],
-        "Accept-Encoding": ["gzip, deflate"],
-        "cache-control": ["no-cache"],
-        "CloudFront-Forwarded-Proto": ["https"],
-        "CloudFront-Is-Desktop-Viewer": ["true"],
-        "CloudFront-Is-Mobile-Viewer": ["false"],
-        "CloudFront-Is-SmartTV-Viewer": ["false"],
-        "CloudFront-Is-Tablet-Viewer": ["false"],
-        "CloudFront-Viewer-Country": ["US"],
-        "Content-Type": ["application/json"],
-        "headerName": ["headerValue"],
-        "Host": ["gy415nuibc.execute-api.us-east-1.amazonaws.com"],
-        "Postman-Token": ["9f583ef0-ed83-4a38-aef3-eb9ce3f7a57f"],
-        "User-Agent": ["PostmanRuntime/2.4.5"],
-        "Via": ["1.1 d98420743a69852491bbdea73f7680bd.cloudfront.net (CloudFront)"],
-        "X-Amz-Cf-Id": ["pn-PWIJc6thYnZm5P0NMgOUglL1DYtl0gdeJky8tqsg8iS_sgsKD1A=="],
-        "X-Forwarded-For": ["54.240.196.186, 54.182.214.83"],
-        "X-Forwarded-Port": ["443"],
-        "X-Forwarded-Proto": ["https"]
-    },
+	"path": "/hello/world",
+	"httpMethod": "POST",
+	"headers": {
+		"Accept": "*/*",
+		"Accept-Encoding": "gzip, deflate",
+		"cache-control": "no-cache",
+		"CloudFront-Forwarded-Proto": "https",
+		"CloudFront-Is-Desktop-Viewer": "true",
+		"CloudFront-Is-Mobile-Viewer": "false",
+		"CloudFront-Is-SmartTV-Viewer": "false",
+		"CloudFront-Is-Tablet-Viewer": "false",
+		"CloudFront-Viewer-Country": "US",
+		"Content-Type": "application/json",
+		"headerName": "headerValue",
+		"Host": "gy415nuibc.execute-api.us-east-1.amazonaws.com",
+		"Postman-Token": "9f583ef0-ed83-4a38-aef3-eb9ce3f7a57f",
+		"User-Agent": "PostmanRuntime/2.4.5",
+		"Via": "1.1 d98420743a69852491bbdea73f7680bd.cloudfront.net (CloudFront)",
+		"X-Amz-Cf-Id": "pn-PWIJc6thYnZm5P0NMgOUglL1DYtl0gdeJky8tqsg8iS_sgsKD1A==",
+		"X-Forwarded-For": "54.240.196.186, 54.182.214.83",
+		"X-Forwarded-Port": "443",
+		"X-Forwarded-Proto": "https"
+	},
+	"multiValueHeaders": {
+		"Accept": [
+			"*/*"
+		],
+		"Accept-Encoding": [
+			"gzip, deflate"
+		],
+		"cache-control": [
+			"no-cache"
+		],
+		"CloudFront-Forwarded-Proto": [
+			"https"
+		],
+		"CloudFront-Is-Desktop-Viewer": [
+			"true"
+		],
+		"CloudFront-Is-Mobile-Viewer": [
+			"false"
+		],
+		"CloudFront-Is-SmartTV-Viewer": [
+			"false"
+		],
+		"CloudFront-Is-Tablet-Viewer": [
+			"false"
+		],
+		"CloudFront-Viewer-Country": [
+			"US"
+		],
+		"Content-Type": [
+			"application/json"
+		],
+		"headerName": [
+			"headerValue"
+		],
+		"Host": [
+			"gy415nuibc.execute-api.us-east-1.amazonaws.com"
+		],
+		"Postman-Token": [
+			"9f583ef0-ed83-4a38-aef3-eb9ce3f7a57f"
+		],
+		"User-Agent": [
+			"PostmanRuntime/2.4.5"
+		],
+		"Via": [
+			"1.1 d98420743a69852491bbdea73f7680bd.cloudfront.net (CloudFront)"
+		],
+		"X-Amz-Cf-Id": [
+			"pn-PWIJc6thYnZm5P0NMgOUglL1DYtl0gdeJky8tqsg8iS_sgsKD1A=="
+		],
+		"X-Forwarded-For": [
+			"54.240.196.186, 54.182.214.83"
+		],
+		"X-Forwarded-Port": [
+			"443"
+		],
+		"X-Forwarded-Proto": [
+			"https"
+		]
+	},
 	"queryStringParameters": {
 		"name": "me"
-    },
-    "multiValueQueryStringParameters": {
-        "name": ["me"]
-    },
+	},
+	"multiValueQueryStringParameters": {
+		"name": [
+			"me"
+		]
+	},
 	"pathParameters": {
 		"proxy": "hello/world"
 	},
@@ -70,9 +110,9 @@
 			"accountId": "theAccountId",
 			"cognitoIdentityId": "theCognitoIdentityId",
 			"caller": "theCaller",
-            "apiKey": "theApiKey",
-            "apiKeyId": "theApiKeyId",
-            "accessKey": "ANEXAMPLEOFACCESSKEY",
+			"apiKey": "theApiKey",
+			"apiKeyId": "theApiKeyId",
+			"accessKey": "ANEXAMPLEOFACCESSKEY",
 			"sourceIp": "192.168.196.186",
 			"cognitoAuthenticationType": "theCognitoAuthenticationType",
 			"cognitoAuthenticationProvider": "theCognitoAuthenticationProvider",
@@ -92,5 +132,4 @@
 		"apiId": "gy415nuibc"
 	},
 	"body": "{\r\n\t\"a\": 1\r\n}"
-}
-
+}

lambda-http/Cargo.toml

@@ -40,7 +40,7 @@ percent-encoding = "2.2"
 
 [dependencies.aws_lambda_events]
 path = "../lambda-events"
-version = "0.10.0"
+version = "0.11.0"
 default-features = false
 features = ["alb", "apigw"]
 

lambda-http/src/deserializer.rs

@@ -0,0 +1,117 @@
+use crate::request::LambdaRequest;
+use aws_lambda_events::{
+    alb::AlbTargetGroupRequest,
+    apigw::{ApiGatewayProxyRequest, ApiGatewayV2httpRequest, ApiGatewayWebsocketProxyRequest},
+};
+use serde::{de::Error, Deserialize};
+
+const ERROR_CONTEXT: &str = "this function expects a JSON payload from Amazon API Gateway, Amazon Elastic Load Balancer, or AWS Lambda Function URLs, but the data doesn't match any of those services' events";
+
+impl<'de> Deserialize<'de> for LambdaRequest {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let content = match serde::__private::de::Content::deserialize(deserializer) {
+            Ok(content) => content,
+            Err(err) => return Err(err),
+        };
+        #[cfg(feature = "apigw_rest")]
+        if let Ok(res) =
+            ApiGatewayProxyRequest::deserialize(serde::__private::de::ContentRefDeserializer::<D::Error>::new(&content))
+        {
+            return Ok(LambdaRequest::ApiGatewayV1(res));
+        }
+        #[cfg(feature = "apigw_http")]
+        if let Ok(res) = ApiGatewayV2httpRequest::deserialize(
+            serde::__private::de::ContentRefDeserializer::<D::Error>::new(&content),
+        ) {
+            return Ok(LambdaRequest::ApiGatewayV2(res));
+        }
+        #[cfg(feature = "alb")]
+        if let Ok(res) =
+            AlbTargetGroupRequest::deserialize(serde::__private::de::ContentRefDeserializer::<D::Error>::new(&content))
+        {
+            return Ok(LambdaRequest::Alb(res));
+        }
+        #[cfg(feature = "apigw_websockets")]
+        if let Ok(res) = ApiGatewayWebsocketProxyRequest::deserialize(serde::__private::de::ContentRefDeserializer::<
+            D::Error,
+        >::new(&content))
+        {
+            return Ok(LambdaRequest::WebSocket(res));
+        }
+
+        Err(Error::custom(ERROR_CONTEXT))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_deserialize_apigw_rest() {
+        let data = include_bytes!("../../lambda-events/src/fixtures/example-apigw-request.json");
+
+        let req: LambdaRequest = serde_json::from_slice(data).expect("failed to deserialze apigw rest data");
+        match req {
+            LambdaRequest::ApiGatewayV1(req) => {
+                assert_eq!("12345678912", req.request_context.account_id.unwrap());
+            }
+            other => panic!("unexpected request variant: {:?}", other),
+        }
+    }
+
+    #[test]
+    fn test_deserialize_apigw_http() {
+        let data = include_bytes!("../../lambda-events/src/fixtures/example-apigw-v2-request-iam.json");
+
+        let req: LambdaRequest = serde_json::from_slice(data).expect("failed to deserialze apigw http data");
+        match req {
+            LambdaRequest::ApiGatewayV2(req) => {
+                assert_eq!("123456789012", req.request_context.account_id.unwrap());
+            }
+            other => panic!("unexpected request variant: {:?}", other),
+        }
+    }
+
+    #[test]
+    fn test_deserialize_alb() {
+        let data = include_bytes!(
+            "../../lambda-events/src/fixtures/example-alb-lambda-target-request-multivalue-headers.json"
+        );
+
+        let req: LambdaRequest = serde_json::from_slice(data).expect("failed to deserialze alb rest data");
+        match req {
+            LambdaRequest::Alb(req) => {
+                assert_eq!(
+                    "arn:aws:elasticloadbalancing:us-east-1:123456789012:targetgroup/lambda-target/abcdefgh",
+                    req.request_context.elb.target_group_arn.unwrap()
+                );
+            }
+            other => panic!("unexpected request variant: {:?}", other),
+        }
+    }
+
+    #[test]
+    fn test_deserialize_apigw_websocket() {
+        let data =
+            include_bytes!("../../lambda-events/src/fixtures/example-apigw-websocket-request-without-method.json");
+
+        let req: LambdaRequest = serde_json::from_slice(data).expect("failed to deserialze apigw websocket data");
+        match req {
+            LambdaRequest::WebSocket(req) => {
+                assert_eq!("CONNECT", req.request_context.event_type.unwrap());
+            }
+            other => panic!("unexpected request variant: {:?}", other),
+        }
+    }
+
+    #[test]
+    fn test_deserialize_error() {
+        let err = serde_json::from_str::<LambdaRequest>("{\"command\": \"hi\"}").unwrap_err();
+
+        assert_eq!(ERROR_CONTEXT, err.to_string());
+    }
+}

lambda-http/src/lib.rs

@@ -70,6 +70,7 @@ pub use lambda_runtime::{self, service_fn, tower, Context, Error, Service};
 use request::RequestFuture;
 use response::ResponseFuture;
 
+mod deserializer;
 pub mod ext;
 pub mod request;
 mod response;

lambda-http/src/request.rs

@@ -20,8 +20,10 @@ use aws_lambda_events::apigw::{ApiGatewayWebsocketProxyRequest, ApiGatewayWebsoc
 use aws_lambda_events::{encodings::Body, query_map::QueryMap};
 use http::header::HeaderName;
 use http::{HeaderMap, HeaderValue};
+
 use serde::{Deserialize, Serialize};
 use serde_json::error::Error as JsonError;
+
 use std::future::Future;
 use std::pin::Pin;
 use std::{env, io::Read, mem};
@@ -33,8 +35,7 @@ use url::Url;
 /// This is not intended to be a type consumed by crate users directly. The order
 /// of the variants are notable. Serde will try to deserialize in this order.
 #[doc(hidden)]
-#[derive(Deserialize, Debug)]
-#[serde(untagged)]
+#[derive(Debug)]
 pub enum LambdaRequest {
     #[cfg(feature = "apigw_rest")]
     ApiGatewayV1(ApiGatewayProxyRequest),