feature: Add com.atproto.identity.resolveHandle to atproto-client

crates/atproto-client/src/com_atproto_identity.rs

···
+//! AT Protocol identity XRPC methods implementation.
+//!
+//! This module provides client implementations for com.atproto.identity namespace methods,
+//! including handle resolution functionality.
+
+use std::collections::HashMap;
+
+use anyhow::Result;
+use serde::{Deserialize, de::DeserializeOwned};
+
+use crate::{
+    client::{get_dpop_json, get_json, DPoPAuth}, errors::SimpleError, url::URLBuilder
+};
+
+/// Response from the com.atproto.identity.resolveHandle XRPC method.
+///
+/// This enum represents either a successful handle resolution containing a DID,
+/// or an error response from the server.
+#[cfg_attr(debug_assertions, derive(Debug))]
+#[derive(Deserialize, Clone)]
+#[serde(untagged)]
+pub enum ResolveHandleResponse {
+    /// Successful handle resolution response.
+    Response {
+        /// The DID that the handle resolves to.
+        did: String,
+
+        /// Additional fields not part of the standard response
+        #[serde(flatten)]
+        extra: HashMap<String, serde_json::Value>,
+    },
+
+    /// Error response from the server
+    Error(SimpleError),
+}
+
+/// Resolves an AT Protocol handle to its associated DID.
+///
+/// Makes an XRPC call to com.atproto.identity.resolveHandle to resolve
+/// a handle (e.g., "user.bsky.social") to its corresponding DID.
+///
+/// # Arguments
+///
+/// * `http_client` - The HTTP client to use for the request
+/// * `dpop_auth` - Optional DPoP authentication credentials
+/// * `base_url` - The base URL of the AT Protocol service
+/// * `handle` - The handle to resolve
+///
+/// # Returns
+///
+/// Returns a `ResolveHandleResponse` containing either the resolved DID
+/// or an error response from the server.
+pub async fn resolve_handle<T: DeserializeOwned>(
+    http_client: &reqwest::Client,
+    dpop_auth: Option<&DPoPAuth>,
+    base_url: &str,
+    handle: String,
+) -> Result<ResolveHandleResponse> {
+    let mut url_builder = URLBuilder::new(base_url);
+    url_builder.path("/xrpc/com.atproto.identity.resolveHandle");
+
+    url_builder.param("handle", &handle);
+
+    let url = url_builder.build();
+
+    if let Some(dpop_auth) = dpop_auth {
+        get_dpop_json(http_client, dpop_auth, &url)
+            .await
+            .and_then(|value| serde_json::from_value(value).map_err(|err| err.into()))
+    } else {
+        get_json(http_client, &url)
+            .await
+            .and_then(|value| serde_json::from_value(value).map_err(|err| err.into()))
+    }
+}

crates/atproto-client/src/lib.rs

···
 
 mod com_atproto_repo;
 mod com_atproto_server;
+mod com_atproto_identity;
 
 /// AT Protocol namespace modules.
 pub mod com {
···
         /// Server operations for AT Protocol authentication and session management.
         pub mod server {
             pub use crate::com_atproto_server::*;
+        }
+
+        /// Identity operations for AT Protocol handle and DID resolution.
+        pub mod identity {
+            pub use crate::com_atproto_identity::*;
         }
     }
 }