Allow disabling grpc at the build level

Cargo.toml

@@ -11,14 +11,18 @@ license = "MIT"
 keywords = ["nostr", "server"]
 categories = ["network-programming", "web-programming"]
 
+[features]
+default = ["grpc"]
+grpc = ["tonic", "prost", "tonic-build"]
+
 [dependencies]
 clap = { version = "4.0.32", features = ["env", "default", "derive"]}
 tracing = "0.1.37"
 tracing-appender = "0.2.2"
 tracing-subscriber = "0.3.16"
 tokio = { version = "1", features = ["full", "tracing", "signal"] }
-prost = "0.11"
+prost = { version = "0.11", optional = true }
-tonic = "0.8.3"
+tonic = { version = "0.8.3", optional = true }
 console-subscriber = "0.1.8"
 futures = "0.3"
 futures-util = "0.3"
@@ -63,4 +67,4 @@ log = "0.4"
 anyhow = "1"
 
 [build-dependencies]
-tonic-build = { version="0.8.3", features = ["prost"] }
+tonic-build = { version="0.8.3", features = ["prost"], optional = true }

build.rs

@@ -1,4 +1,5 @@
 fn main() -> Result<(), Box<dyn std::error::Error>> {
+    #[cfg(feature = "grpc")]
     tonic_build::configure()
         .build_server(false)
         .protoc_arg("--experimental_allow_proto3_optional")

src/db.rs

@@ -2,6 +2,7 @@
 use crate::config::Settings;
 use crate::error::{Error, Result};
 use crate::event::Event;
+#[cfg(feature = "grpc")]
 use crate::nauthz;
 use crate::notice::Notice;
 use crate::payment::PaymentMessage;
@@ -136,6 +137,7 @@ pub async fn db_writer(
     }
     // create a client if GRPC is enabled.
     // Check with externalized event admitter service, if one is defined.
+    #[cfg(feature = "grpc")]
     let mut grpc_client = if let Some(svr) = settings.grpc.event_admission_server {
         Some(nauthz::EventAuthzService::connect(&svr).await)
     } else {
@@ -345,11 +347,13 @@ pub async fn db_writer(
             }
         }
 
+        // GRPC check
+        #[cfg(feature = "grpc")]
+        {
             // nip05 address
             let nip05_address: Option<crate::nip05::Nip05Name> =
                 validation.and_then(|x| x.ok().map(|y| y.name));
 
-        // GRPC check
             if let Some(ref mut c) = grpc_client {
                 trace!("checking if grpc permits");
                 let grpc_start = Instant::now();
@@ -389,6 +393,7 @@ pub async fn db_writer(
                     }
                 }
             }
+        }
 
         // TODO: cache recent list of authors to remove a DB call.
         let start = Instant::now();

src/error.rs

@@ -66,6 +66,7 @@ pub enum Error {
     ChannelClosed,
     #[error("Authz error")]
     AuthzError,
+    #[cfg(feature = "grpc")]
     #[error("Tonic GRPC error")]
     TonicError(tonic::Status),
     #[error("Invalid AUTH message")]
@@ -151,6 +152,7 @@ impl From<config::ConfigError> for Error {
     }
 }
 
+#[cfg(feature = "grpc")]
 impl From<tonic::Status> for Error {
     /// Wrap Config error
     fn from(r: tonic::Status) -> Self {

src/lib.rs

@@ -8,6 +8,7 @@ pub mod error;
 pub mod event;
 pub mod hexrange;
 pub mod info;
+#[cfg(feature = "grpc")]
 pub mod nauthz;
 pub mod nip05;
 pub mod notice;