feat(fs): Reimplement with different data model

TODO:
- Write documentation.
- Implement announcing & querying replicas on mainline DHT.
    - After querying, implement node discovery and joining document swarms.

Cargo.toml

@@ -10,12 +10,17 @@ async-trait = "0.1.79"
 bincode = "1.3.3"
 bytes = "1.6.0"
 chrono = "0.4.37"
+derive_more = "0.99.17"
+futures = "0.3.30"
+hex = "0.4.3"
 iroh = "0.13.0"
+iroh-mainline-content-discovery = "0.5.0"
+mainline = "1.4.0"
 miette = { version = "7.2.0", features = ["fancy"] }
 path-clean = "1.0.1"
 quic-rpc = "0.7.0"
 rand_core = "0.6.4"
 serde = "1.0.197"
+sha3 = "0.10.8"
 thiserror = "1.0.58"
-vfs = { version = "0.12.0", features = ["async-vfs"] }
-wnfs = "0.2.2"
+tokio = "1.37.0"

src/discovery.rs

@@ -0,0 +1,102 @@
+use crate::error::OkuDiscoveryError;
+use futures::StreamExt;
+use iroh::{
+    bytes::{Hash, HashAndFormat},
+    sync::NamespaceId,
+    ticket::BlobTicket,
+};
+use iroh_mainline_content_discovery::protocol::{Query, QueryFlags};
+use iroh_mainline_content_discovery::to_infohash;
+use iroh_mainline_content_discovery::UdpDiscovery;
+use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4};
+use std::{error::Error, str::FromStr};
+
+/*
+The `ContentRequest` enum is derived from the `ContentArg` enum in the `iroh-examples` repository (https://github.com/n0-computer/iroh-examples/blob/6f184933efa72eec1d8cf2e8d07905650c0fdb46/content-discovery/iroh-mainline-content-discovery-cli/src/args.rs#L23).
+*/
+#[derive(Debug, Clone, derive_more::From)]
+/// A request for content, which can be a raw hash, a hash and format pair, or a blob ticket.
+pub enum ContentRequest {
+    /// A raw hash.
+    Hash(Hash),
+    /// A hash and format pair.
+    HashAndFormat(HashAndFormat),
+    /// A blob ticket.
+    Ticket(BlobTicket),
+}
+
+impl ContentRequest {
+    /// Get the hash and format pair for this content request.
+    pub fn hash_and_format(&self) -> HashAndFormat {
+        match self {
+            ContentRequest::Hash(hash) => HashAndFormat::raw(*hash),
+            ContentRequest::HashAndFormat(haf) => *haf,
+            ContentRequest::Ticket(ticket) => HashAndFormat {
+                hash: ticket.hash(),
+                format: ticket.format(),
+            },
+        }
+    }
+}
+
+impl FromStr for ContentRequest {
+    type Err = Box<dyn Error>;
+    fn from_str(s: &str) -> Result<Self, Box<dyn Error>> {
+        if let Ok(hash) = Hash::from_str(s) {
+            Ok(hash.into())
+        } else if let Ok(haf) = HashAndFormat::from_str(s) {
+            Ok(haf.into())
+        } else if let Ok(ticket) = BlobTicket::from_str(s) {
+            Ok(ticket.into())
+        } else {
+            Err(OkuDiscoveryError::InvalidHashAndFormat.into())
+        }
+    }
+}
+
+async fn query_dht(
+    content: ContentRequest,
+    partial: bool,
+    verified: bool,
+    udp_port: Option<u16>,
+) -> Result<(), Box<dyn Error>> {
+    let bind_addr = SocketAddr::V4(SocketAddrV4::new(
+        Ipv4Addr::UNSPECIFIED,
+        udp_port.unwrap_or_default(),
+    ));
+    let discovery = UdpDiscovery::new(bind_addr).await?;
+    let dht = mainline::Dht::default();
+    let q = Query {
+        content: content.hash_and_format(),
+        flags: QueryFlags {
+            complete: !partial,
+            verified: verified,
+        },
+    };
+    println!("content corresponds to infohash {}", to_infohash(q.content));
+
+    let mut stream = discovery.query_dht(dht, q).await?;
+    while let Some(announce) = stream.next().await {
+        if announce.verify().is_ok() {
+            println!("found verified provider {}", announce.host);
+        } else {
+            println!("got wrong signed announce!");
+        }
+    }
+    Ok(())
+}
+
+pub async fn query_fs_entry(
+    id: NamespaceId,
+    partial: bool,
+    verified: bool,
+    udp_port: Option<u16>,
+) -> Result<(), Box<dyn Error>> {
+    query_dht(
+        ContentRequest::Hash(Hash::new(id)),
+        partial,
+        verified,
+        udp_port,
+    )
+    .await
+}

src/error.rs

@@ -41,3 +41,10 @@ pub enum OkuFsError {
     /// File system root has not been loaded.
     RootNotLoaded,
 }
+
+#[derive(Error, Debug, Diagnostic)]
+pub enum OkuDiscoveryError {
+    #[error("Invalid hash and format.")]
+    #[diagnostic(code(discovery::invalid_hash_and_format), url(docsrs))]
+    InvalidHashAndFormat,
+}