Message ingestion (not tested)

crates/utils/Cargo.toml

@@ -13,6 +13,7 @@ serde = { version = "1.0", features = ["derive"]}
 tracing = "0.1"
 mail-auth = { git = "https://github.com/stalwartlabs/mail-auth" }
 smtp-proto = { git = "https://github.com/stalwartlabs/smtp-proto" }
+mail-send = { git = "https://github.com/stalwartlabs/mail-send", default-features = false, features = ["cram-md5", "skip-ehlo"] }
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 tracing-appender = "0.2"
 tracing-opentelemetry = "0.18.0"

crates/utils/src/ipc.rs

@@ -0,0 +1,116 @@
+use std::{borrow::Cow, path::PathBuf};
+
+use mail_send::Credentials;
+use tokio::{fs, io::AsyncReadExt, sync::oneshot};
+
+pub enum DeliveryEvent {
+    Ingest {
+        message: IngestMessage,
+        result_tx: oneshot::Sender<Vec<DeliveryResult>>,
+    },
+    Lookup(LookupItem),
+    Stop,
+}
+
+pub struct IngestMessage {
+    pub sender_address: String,
+    pub recipients: Vec<String>,
+    pub message_path: PathBuf,
+    pub message_size: usize,
+}
+
+#[derive(Debug, Clone)]
+pub enum DeliveryResult {
+    Success,
+    TemporaryFailure {
+        reason: Cow<'static, str>,
+    },
+    PermanentFailure {
+        code: [u8; 3],
+        reason: Cow<'static, str>,
+    },
+}
+
+#[derive(Clone, PartialEq, Eq, Hash)]
+pub enum Item {
+    IsAccount(String),
+    Authenticate(Credentials<String>),
+    Verify(String),
+    Expand(String),
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum LookupResult {
+    True,
+    False,
+    Values(Vec<String>),
+}
+
+#[derive(Debug)]
+pub struct LookupItem {
+    pub item: Item,
+    pub result: oneshot::Sender<LookupResult>,
+}
+
+impl From<LookupResult> for bool {
+    fn from(value: LookupResult) -> Self {
+        matches!(value, LookupResult::True | LookupResult::Values(_))
+    }
+}
+
+impl From<bool> for LookupResult {
+    fn from(value: bool) -> Self {
+        if value {
+            LookupResult::True
+        } else {
+            LookupResult::False
+        }
+    }
+}
+
+impl From<Vec<String>> for LookupResult {
+    fn from(value: Vec<String>) -> Self {
+        if !value.is_empty() {
+            LookupResult::Values(value)
+        } else {
+            LookupResult::False
+        }
+    }
+}
+
+impl core::fmt::Debug for Item {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::IsAccount(arg0) => f.debug_tuple("Rcpt").field(arg0).finish(),
+            Self::Authenticate(_) => f.debug_tuple("Auth").finish(),
+            Self::Expand(arg0) => f.debug_tuple("Expn").field(arg0).finish(),
+            Self::Verify(arg0) => f.debug_tuple("Vrfy").field(arg0).finish(),
+        }
+    }
+}
+
+impl IngestMessage {
+    pub async fn read_message(&self) -> Result<Vec<u8>, ()> {
+        let mut raw_message = vec![0u8; self.message_size];
+        let mut file = fs::File::open(&self.message_path).await.map_err(|err| {
+            tracing::error!(
+                context = "read_message",
+                event = "error",
+                "Failed to open message file {}: {}",
+                self.message_path.display(),
+                err
+            );
+        })?;
+        file.read_exact(&mut raw_message).await.map_err(|err| {
+            tracing::error!(
+                context = "read_message",
+                event = "error",
+                "Failed to read {} bytes file {} from disk: {}",
+                self.message_size,
+                self.message_path.display(),
+                err
+            );
+        })?;
+        Ok(raw_message)
+    }
+}

crates/utils/src/lib.rs

@@ -27,6 +27,7 @@ use config::Config;
 
 pub mod codec;
 pub mod config;
+pub mod ipc;
 pub mod listener;
 pub mod map;