fn try_from()

in lambda-runtime/src/types.rs [124:166]
40 lines of code
3 McCabe index (conditional complexity)

    fn try_from(headers: HeaderMap) -> Result<Self, Self::Error> {
        let client_context: Option<ClientContext> = if let Some(value) = headers.get("lambda-runtime-client-context") {
            serde_json::from_str(value.to_str()?)?
        } else {
            None
        };

        let identity: Option<CognitoIdentity> = if let Some(value) = headers.get("lambda-runtime-cognito-identity") {
            serde_json::from_str(value.to_str()?)?
        } else {
            None
        };

        let ctx = Context {
            request_id: headers
                .get("lambda-runtime-aws-request-id")
                .expect("missing lambda-runtime-aws-request-id header")
                .to_str()?
                .to_owned(),
            deadline: headers
                .get("lambda-runtime-deadline-ms")
                .expect("missing lambda-runtime-deadline-ms header")
                .to_str()?
                .parse::<u64>()?,
            invoked_function_arn: headers
                .get("lambda-runtime-invoked-function-arn")
                .unwrap_or(&HeaderValue::from_static(
                    "No header lambda-runtime-invoked-function-arn found.",
                ))
                .to_str()?
                .to_owned(),
            xray_trace_id: headers
                .get("lambda-runtime-trace-id")
                .unwrap_or(&HeaderValue::from_static(""))
                .to_str()?
                .to_owned(),
            client_context,
            identity,
            ..Default::default()
        };

        Ok(ctx)
    }