Update resolvers, add examples for oauth

Cargo.toml

@@ -61,6 +61,7 @@ sha2 = "0.10.8"
 
 # Networking
 futures = { version = "0.3.30", default-features = false, features = ["alloc"] }
+hickory-resolver = "0.24.1"
 http = "1.1.0"
 tokio = { version = "1.39", default-features = false }
 

atrium-oauth/oauth-client/Cargo.toml

@@ -21,6 +21,7 @@ base64.workspace = true
 chrono.workspace = true
 ecdsa = { workspace = true, features = ["signing"] }
 elliptic-curve = { workspace = true }
+futures.workspace = true
 jose-jwa.workspace = true
 jose-jwk = { workspace = true, features = ["p256"] }
 p256 = { workspace = true, features = ["ecdsa"] }
@@ -33,6 +34,7 @@ sha2.workspace = true
 thiserror.workspace = true
 
 [dev-dependencies]
+hickory-resolver.workspace = true
 tokio = { workspace = true, features = ["macros", "rt-multi-thread"] }
 
 [features]

atrium-oauth/oauth-client/examples/main.rs

@@ -0,0 +1,88 @@
+use atrium_oauth_client::identity::handle::{DnsTxtResolver, HandleResolverImpl};
+use atrium_oauth_client::identity::DidResolverConfig;
+use atrium_oauth_client::identity::HandleResolverConfig;
+use atrium_oauth_client::store::state::MemoryStateStore;
+use atrium_oauth_client::{
+    AtprotoLocalhostClientMetadata, AuthorizeOptions, OAuthClient, OAuthClientConfig,
+    OAuthResolverConfig,
+};
+use atrium_xrpc::http::Uri;
+use hickory_resolver::TokioAsyncResolver;
+use std::io::{stdin, stdout, BufRead, Write};
+use std::sync::Arc;
+
+struct HickoryDnsTxtResolver {
+    resolver: TokioAsyncResolver,
+}
+
+impl HickoryDnsTxtResolver {
+    pub fn new() -> Self {
+        Self {
+            resolver: TokioAsyncResolver::tokio_from_system_conf()
+                .expect("failed to create resolver"),
+        }
+    }
+}
+
+#[async_trait::async_trait]
+impl DnsTxtResolver for HickoryDnsTxtResolver {
+    async fn resolve(
+        &self,
+        query: &str,
+    ) -> core::result::Result<Vec<String>, Box<dyn std::error::Error + Send + Sync + 'static>> {
+        Ok(self
+            .resolver
+            .txt_lookup(query)
+            .await?
+            .iter()
+            .map(|txt| txt.to_string())
+            .collect())
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let config = OAuthClientConfig {
+        client_metadata: AtprotoLocalhostClientMetadata {
+            redirect_uris: vec!["http://127.0.0.1".to_string()],
+        },
+        keys: None,
+        resolver: OAuthResolverConfig {
+            did: DidResolverConfig::default(),
+            handle: HandleResolverConfig {
+                r#impl: HandleResolverImpl::Atproto(Arc::new(HickoryDnsTxtResolver::new())),
+            },
+        },
+        state_store: MemoryStateStore::default(),
+    };
+    let client = OAuthClient::new(config)?;
+    println!(
+        "Authorization url: {}",
+        client
+            .authorize(
+                std::env::var("HANDLE").unwrap_or(String::from("https://bsky.social")),
+                AuthorizeOptions {
+                    scopes: Some(vec![String::from("atproto")]),
+                    ..Default::default()
+                }
+            )
+            .await?
+    );
+
+    // Click the URL and sign in,
+    // then copy and paste the URL like “http://127.0.0.1/?iss=...&code=...” after it is redirected.
+
+    print!("Redirected url: ");
+    stdout().lock().flush()?;
+    let mut url = String::new();
+    stdin().lock().read_line(&mut url)?;
+
+    let uri = url.trim().parse::<Uri>()?;
+    let params = serde_html_form::from_str(uri.query().unwrap())?;
+    println!(
+        "{}",
+        serde_json::to_string_pretty(&client.callback(params).await?)?
+    );
+
+    Ok(())
+}

atrium-oauth/oauth-client/src/error.rs

@@ -7,7 +7,7 @@ pub enum Error {
     #[error(transparent)]
     Keyset(#[from] crate::keyset::Error),
     #[error(transparent)]
-    Resolver(#[from] crate::resolver::Error),
+    Identity(#[from] crate::identity::Error),
     #[error(transparent)]
     ServerAgent(#[from] crate::server_agent::Error),
     #[error("authorize error: {0}")]