Client for VSCode Debug Plugin (#829)

core/Cargo.toml

@@ -18,6 +18,7 @@ otel = ["dep:opentelemetry", "dep:opentelemetry_sdk", "dep:opentelemetry-otlp",
     "dep:opentelemetry-prometheus", "dep:hyper", "dep:hyper-util", "dep:http-body-util"]
 tokio-console = ["console-subscriber"]
 ephemeral-server = ["dep:flate2", "dep:reqwest", "dep:tar", "dep:zip"]
+debug-plugin = ["dep:reqwest"]
 
 [dependencies]
 anyhow = "1.0"

core/src/debug_client.rs

@@ -0,0 +1,78 @@
+//! Defines an http client that is used for the VSCode debug plugin and any other associated
+//! machinery.
+
+use anyhow::Context;
+use hyper::http::HeaderValue;
+use prost::Message;
+use reqwest::{self, header::HeaderMap};
+use std::time::Duration;
+use temporal_sdk_core_protos::temporal::api::history::v1::History;
+use url::Url;
+
+/// A client for interacting with the VSCode debug plugin
+#[derive(Clone)]
+pub struct DebugClient {
+    /// URL for the local instance of the debugger server
+    debugger_url: Url,
+    client: reqwest::Client,
+}
+
+#[derive(Clone, serde::Serialize)]
+struct WFTStartedMsg {
+    event_id: i64,
+}
+
+impl DebugClient {
+    /// Create a new instance of a DebugClient with the specified url and client name/version
+    /// strings.
+    pub fn new(
+        url: String,
+        client_name: &str,
+        client_version: &str,
+    ) -> Result<DebugClient, anyhow::Error> {
+        let mut client = reqwest::ClientBuilder::new();
+        client = client.default_headers({
+            let mut hm = HeaderMap::new();
+            hm.insert("temporal-client-name", HeaderValue::from_str(client_name)?);
+            hm.insert(
+                "temporal-client-version",
+                HeaderValue::from_str(client_version)?,
+            );
+            hm
+        });
+        let client = client.build()?;
+        Ok(DebugClient {
+            debugger_url: Url::parse(&url).context(
+                "debugger url malformed, is the TEMPORAL_DEBUGGER_PLUGIN_URL env var correct?",
+            )?,
+            client,
+        })
+    }
+
+    /// Get the history from the instance of the debug plugin server
+    pub async fn get_history(&self) -> Result<History, anyhow::Error> {
+        let url = self.debugger_url.join("history")?;
+        let resp = self.client.get(url).send().await?;
+
+        let bytes = resp.bytes().await?;
+        Ok(History::decode(bytes)?)
+    }
+
+    /// Post to current-wft-started to tell the debug plugin which event we've most recently made it
+    /// to
+    pub async fn post_wft_started(
+        &self,
+        event_id: &i64,
+    ) -> Result<reqwest::Response, anyhow::Error> {
+        let url = self.debugger_url.join("current-wft-started")?;
+        Ok(self
+            .client
+            .get(url)
+            .timeout(Duration::from_secs(5))
+            .json(&WFTStartedMsg {
+                event_id: *event_id,
+            })
+            .send()
+            .await?)
+    }
+}

core/src/lib.rs

@@ -12,6 +12,8 @@ extern crate tracing;
 extern crate core;
 
 mod abstractions;
+#[cfg(feature = "debug-plugin")]
+pub mod debug_client;
 #[cfg(feature = "ephemeral-server")]
 pub mod ephemeral_server;
 mod internal_flags;