Add support for Direct Lambda Resolver event format

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

@@ -117,6 +117,112 @@ where
     pub ttl_override: Option<i64>,
 }
 
+/// `AppSyncResolverEvent` represents the default payload structure sent by AWS AppSync
+/// when using **Direct Lambda Resolvers** (i.e., when both request and response mapping
+/// templates are disabled).
+///
+/// This structure includes the full AppSync **Context object**, as described in the
+/// [AppSync Direct Lambda resolver reference](https://docs.aws.amazon.com/appsync/latest/devguide/direct-lambda-reference.html).
+///
+/// It is recommended when working without VTL templates and relying on the standard
+/// AppSync-to-Lambda event format.
+///
+/// See also:
+/// - [AppSync resolver mapping template context reference](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-context-reference.html)
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+pub struct AppSyncDirectResolverEvent<TArguments = Value, TSource = Value, TStash = Value>
+where
+    TArguments: Serialize + DeserializeOwned,
+    TSource: Serialize + DeserializeOwned,
+    TStash: Serialize + DeserializeOwned,
+{
+    #[serde(bound = "")]
+    pub arguments: Option<TArguments>,
+    pub identity: Option<AppSyncIdentity>,
+    #[serde(bound = "")]
+    pub source: Option<TSource>,
+    pub request: AppSyncRequest,
+    pub info: AppSyncInfo,
+    #[serde(default)]
+    pub prev: Option<AppSyncPrevResult>,
+    #[serde(bound = "")]
+    pub stash: TStash,
+}
+
+/// `AppSyncRequest` contains request-related metadata for a resolver invocation,
+/// including client-sent headers and optional custom domain name.
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AppSyncRequest {
+    #[serde(deserialize_with = "deserialize_lambda_map")]
+    #[serde(default)]
+    #[serde(bound = "")]
+    pub headers: HashMap<String, Option<String>>,
+    #[serde(default)]
+    pub domain_name: Option<String>,
+}
+
+/// `AppSyncInfo` contains metadata about the current GraphQL field being resolved.
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AppSyncInfo<T = Value>
+where
+    T: Serialize + DeserializeOwned,
+{
+    #[serde(default)]
+    pub selection_set_list: Vec<String>,
+    #[serde(rename = "selectionSetGraphQL")]
+    pub selection_set_graphql: String,
+    pub parent_type_name: String,
+    pub field_name: String,
+    #[serde(bound = "")]
+    pub variables: T,
+}
+
+/// `AppSyncPrevResult` contains the result of the previous step in a pipeline resolver.
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+pub struct AppSyncPrevResult<T = Value>
+where
+    T: Serialize + DeserializeOwned,
+{
+    #[serde(bound = "")]
+    pub result: T,
+}
+
+/// `AppSyncIdentity` represents the identity of the caller as determined by the
+/// configured AppSync authorization mechanism (IAM, Cognito, OIDC, or Lambda).
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+#[serde(untagged, rename_all = "camelCase")]
+pub enum AppSyncIdentity {
+    IAM(AppSyncIamIdentity),
+    Cognito(AppSyncCognitoIdentity),
+    OIDC(AppSyncIdentityOIDC),
+    Lambda(AppSyncIdentityLambda),
+}
+
+/// `AppSyncIdentityOIDC` represents identity information when using OIDC-based authorization.
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+pub struct AppSyncIdentityOIDC<T = Value>
+where
+    T: Serialize + DeserializeOwned,
+{
+    #[serde(bound = "")]
+    pub claims: T,
+    pub issuer: String,
+    pub sub: String,
+}
+
+/// `AppSyncIdentityLambda` represents identity information when using AWS Lambda
+#[derive(Debug, Clone, Eq, PartialEq, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AppSyncIdentityLambda<T = Value>
+where
+    T: Serialize + DeserializeOwned,
+{
+    #[serde(bound = "")]
+    pub resolver_context: T,
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -160,4 +266,14 @@ mod test {
         let reparsed: AppSyncLambdaAuthorizerResponse = serde_json::from_slice(output.as_bytes()).unwrap();
         assert_eq!(parsed, reparsed);
     }
+
+    #[test]
+    #[cfg(feature = "appsync")]
+    fn example_appsync_direct_resolver() {
+        let data = include_bytes!("../../fixtures/example-appsync-direct-resolver.json");
+        let parsed: AppSyncDirectResolverEvent = serde_json::from_slice(data).unwrap();
+        let output: String = serde_json::to_string(&parsed).unwrap();
+        let reparsed: AppSyncDirectResolverEvent = serde_json::from_slice(output.as_bytes()).unwrap();
+        assert_eq!(parsed, reparsed);
+    }
 }

lambda-events/src/fixtures/example-appsync-direct-resolver.json

@@ -0,0 +1,64 @@
+{
+    "arguments": {
+        "input": "foo"
+    },
+    "identity": {
+        "sourceIp": [
+            "x.x.x.x"
+        ],
+        "userArn": "arn:aws:iam::123456789012:user/appsync",
+        "accountId": "666666666666",
+        "user": "AIDAAAAAAAAAAAAAAAAAA"
+    },
+    "info": {
+        "fieldName": "greet",
+        "parentTypeName": "Query",
+        "selectionSetGraphQL": "",
+        "selectionSetList": [],
+        "variables": {
+            "inputVar": "foo"
+        }
+    },
+    "prev": null,
+    "request": {
+        "domainName": null,
+        "headers": {
+            "accept": "application/json, text/plain, */*",
+            "accept-encoding": "gzip, deflate, br, zstd",
+            "accept-language": "en-US,en;q=0.9,ja;q=0.8,en-GB;q=0.7",
+            "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-asn": "17676",
+            "cloudfront-viewer-country": "JP",
+            "content-length": "40",
+            "content-type": "application/json",
+            "host": "2ojpkjk2ejb57l7stgad5o4qiq.appsync-api.ap-northeast-1.amazonaws.com",
+            "origin": "https://ap-northeast-1.console.aws.amazon.com",
+            "priority": "u=1, i",
+            "referer": "https://ap-northeast-1.console.aws.amazon.com/",
+            "sec-ch-ua": "\"Not)A;Brand\";v=\"8\", \"Chromium\";v=\"138\", \"Microsoft Edge\";v=\"138\"",
+            "sec-ch-ua-mobile": "?0",
+            "sec-ch-ua-platform": "\"Windows\"",
+            "sec-fetch-dest": "empty",
+            "sec-fetch-mode": "cors",
+            "sec-fetch-site": "cross-site",
+            "user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36 Edg/138.0.0.0",
+            "via": "2.0 ee337d4db5c7ebfdc8ec0798a1ede776.cloudfront.net (CloudFront)",
+            "x-amz-cf-id": "O3ZflUCq6_TzxjouyYB3zg7-kl7Ze-gXbniM2jJ3hAOfDFpPMGRu3Q==",
+            "x-amz-user-agent": "AWS-Console-AppSync/",
+            "x-amzn-appsync-is-vpce-request": "false",
+            "x-amzn-remote-ip": "x.x.x.x",
+            "x-amzn-requestid": "7ada8740-bbf4-49e8-bf45-f10b3d67159b",
+            "x-amzn-trace-id": "Root=1-68713e21-7a03739120ad60703e794b22",
+            "x-api-key": "***",
+            "x-forwarded-for": "***",
+            "x-forwarded-port": "443",
+            "x-forwarded-proto": "https"
+        }
+    },
+    "source": null,
+    "stash": {}
+}