Genericise the service to send any type of M

Signed-off-by: Adam Cattermole <[email protected]>

src/service.rs

@@ -1,9 +1,96 @@
 pub(crate) mod auth;
 pub(crate) mod rate_limit;
 
+use crate::configuration::ExtensionType;
+use crate::filter::http_context::TracingHeader;
+use crate::service::auth::{AUTH_METHOD_NAME, AUTH_SERVICE_NAME};
+use crate::service::rate_limit::{RATELIMIT_METHOD_NAME, RATELIMIT_SERVICE_NAME};
 use protobuf::Message;
-use proxy_wasm::types::Status;
+use proxy_wasm::hostcalls;
+use proxy_wasm::hostcalls::dispatch_grpc_call;
+use proxy_wasm::types::{Bytes, MapType, Status};
+use std::cell::OnceCell;
+use std::time::Duration;
 
-pub trait Service<M: Message> {
-    fn send(&self, message: M) -> Result<u32, Status>;
+pub struct GrpcServiceHandler {
+    endpoint: String,
+    service_name: String,
+    method_name: String,
+    tracing_headers: Vec<(TracingHeader, Bytes)>,
+}
+
+impl GrpcServiceHandler {
+    fn new_base(
+        endpoint: String,
+        service_name: &str,
+        method_name: &str,
+        tracing_headers: Vec<(TracingHeader, Bytes)>,
+    ) -> Self {
+        Self {
+            endpoint: endpoint.to_owned(),
+            service_name: service_name.to_owned(),
+            method_name: method_name.to_owned(),
+            tracing_headers,
+        }
+    }
+
+    pub fn new(
+        extension_type: ExtensionType,
+        endpoint: String,
+        tracing_headers: Vec<(TracingHeader, Bytes)>,
+    ) -> Self {
+        match extension_type {
+            ExtensionType::Auth => Self::new_base(
+                endpoint,
+                AUTH_SERVICE_NAME,
+                AUTH_METHOD_NAME,
+                tracing_headers,
+            ),
+            ExtensionType::RateLimit => Self::new_base(
+                endpoint,
+                RATELIMIT_SERVICE_NAME,
+                RATELIMIT_METHOD_NAME,
+                tracing_headers,
+            ),
+        }
+    }
+
+    pub fn send<M: Message>(&self, message: M) -> Result<u32, Status> {
+        let msg = Message::write_to_bytes(&message).unwrap();
+        let metadata = self
+            .tracing_headers
+            .iter()
+            .map(|(header, value)| (header.as_str(), value.as_slice()))
+            .collect();
+
+        dispatch_grpc_call(
+            self.endpoint.as_str(),
+            self.service_name.as_str(),
+            self.method_name.as_str(),
+            metadata,
+            Some(&msg),
+            Duration::from_secs(5),
+        )
+    }
+}
+
+pub struct TracingHeaderResolver {
+    tracing_headers: OnceCell<Vec<(TracingHeader, Bytes)>>,
+}
+
+impl TracingHeaderResolver {
+    pub fn get(&self) -> &Vec<(TracingHeader, Bytes)> {
+        self.tracing_headers.get_or_init(|| {
+            let mut headers = Vec::new();
+            for header in TracingHeader::all() {
+                if let Some(value) =
+                    hostcalls::get_map_value_bytes(MapType::HttpRequestHeaders, header.as_str())
+                        .unwrap()
+                {
+                    headers.push((header, value));
+                }
+            }
+            headers
+        })
+    }
 }

src/service/auth.rs

@@ -3,33 +3,20 @@ use crate::envoy::{
     Address, AttributeContext, AttributeContext_HttpRequest, AttributeContext_Peer,
     AttributeContext_Request, CheckRequest, Metadata, SocketAddress,
 };
-use crate::filter::http_context::TracingHeader;
-use crate::service::Service;
 use chrono::{DateTime, FixedOffset, Timelike};
 use protobuf::well_known_types::Timestamp;
 use protobuf::Message;
 use proxy_wasm::hostcalls;
-use proxy_wasm::hostcalls::dispatch_grpc_call;
-use proxy_wasm::types::{Bytes, MapType, Status};
+use proxy_wasm::types::MapType;
 use std::collections::HashMap;
-use std::time::Duration;
 
-const AUTH_SERVICE_NAME: &str = "envoy.service.auth.v3.Authorization";
-const AUTH_METHOD_NAME: &str = "Check";
+pub const AUTH_DATA_ITEM: &str = "host";
+pub const AUTH_SERVICE_NAME: &str = "envoy.service.auth.v3.Authorization";
+pub const AUTH_METHOD_NAME: &str = "Check";
 
-pub struct AuthService {
-    endpoint: String,
-    tracing_headers: Vec<(TracingHeader, Bytes)>,
-}
+pub struct AuthService;
 
 impl AuthService {
-    pub fn new(endpoint: &str, metadata: Vec<(TracingHeader, Bytes)>) -> Self {
-        Self {
-            endpoint: String::from(endpoint),
-            tracing_headers: metadata,
-        }
-    }
-
     pub fn message(ce_host: String) -> CheckRequest {
         AuthService::build_check_req(ce_host)
     }
@@ -93,23 +80,3 @@ impl AuthService {
         peer
     }
 }
-
-impl Service<CheckRequest> for AuthService {
-    fn send(&self, message: CheckRequest) -> Result<u32, Status> {
-        let msg = Message::write_to_bytes(&message).unwrap(); // TODO(adam-cattermole): Error Handling
-        let metadata = self
-            .tracing_headers
-            .iter()
-            .map(|(header, value)| (header.as_str(), value.as_slice()))
-            .collect();
-
-        dispatch_grpc_call(
-            self.endpoint.as_str(),
-            AUTH_SERVICE_NAME,
-            AUTH_METHOD_NAME,
-            metadata,
-            Some(&msg),
-            Duration::from_secs(5),
-        )
-    }
-}

src/service/rate_limit.rs

@@ -1,26 +1,13 @@
 use crate::envoy::{RateLimitDescriptor, RateLimitRequest};
-use crate::filter::http_context::TracingHeader;
-use crate::service::Service;
 use protobuf::{Message, RepeatedField};
-use proxy_wasm::hostcalls::dispatch_grpc_call;
-use proxy_wasm::types::{Bytes, Status};
-use std::time::Duration;
 
-const RATELIMIT_SERVICE_NAME: &str = "envoy.service.ratelimit.v3.RateLimitService";
-const RATELIMIT_METHOD_NAME: &str = "ShouldRateLimit";
-pub struct RateLimitService {
-    endpoint: String,
-    tracing_headers: Vec<(TracingHeader, Bytes)>,
-}
+pub const RATELIMIT_DATA_ITEM: &str = "domain";
+pub const RATELIMIT_SERVICE_NAME: &str = "envoy.service.ratelimit.v3.RateLimitService";
+pub const RATELIMIT_METHOD_NAME: &str = "ShouldRateLimit";
 
-impl RateLimitService {
-    pub fn new(endpoint: &str, metadata: Vec<(TracingHeader, Bytes)>) -> Self {
-        Self {
-            endpoint: String::from(endpoint),
-            tracing_headers: metadata,
-        }
-    }
+pub struct RateLimitService;
 
+impl RateLimitService {
     pub fn message(
         domain: String,
         descriptors: RepeatedField<RateLimitDescriptor>,
@@ -35,26 +22,6 @@ impl RateLimitService {
     }
 }
 
-impl Service<RateLimitRequest> for RateLimitService {
-    fn send(&self, message: RateLimitRequest) -> Result<u32, Status> {
-        let msg = Message::write_to_bytes(&message).unwrap(); // TODO(didierofrivia): Error Handling
-        let metadata = self
-            .tracing_headers
-            .iter()
-            .map(|(header, value)| (header.as_str(), value.as_slice()))
-            .collect();
-
-        dispatch_grpc_call(
-            self.endpoint.as_str(),
-            RATELIMIT_SERVICE_NAME,
-            RATELIMIT_METHOD_NAME,
-            metadata,
-            Some(&msg),
-            Duration::from_secs(5),
-        )
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use crate::envoy::{RateLimitDescriptor, RateLimitDescriptor_Entry, RateLimitRequest};