From a0adf68ffa258d21826fadd85464753ad1d867cb Mon Sep 17 00:00:00 2001
From: Chris Olszewski <chris.olszewski@vercel.com>
Date: Wed, 6 Nov 2024 11:16:37 -0500
Subject: [PATCH] feat(mfe): add env var indicating mfe proxy

---
 crates/turborepo-lib/src/micro_frontends.rs          |  6 ++++++
 .../turborepo-lib/src/task_graph/visitor/command.rs  | 12 ++++++++++++
 crates/turborepo-lib/src/task_graph/visitor/exec.rs  |  1 +
 3 files changed, 19 insertions(+)

diff --git a/crates/turborepo-lib/src/micro_frontends.rs b/crates/turborepo-lib/src/micro_frontends.rs
index 341e0b4e30ceb..8d5891e9725e6 100644
--- a/crates/turborepo-lib/src/micro_frontends.rs
+++ b/crates/turborepo-lib/src/micro_frontends.rs
@@ -49,4 +49,10 @@ impl MicroFrontendsConfigs {
     pub fn get(&self, package_name: &str) -> Option<&HashSet<TaskId<'static>>> {
         self.configs.get(package_name)
     }
+
+    pub fn task_has_mfe_proxy(&self, task_id: &TaskId) -> bool {
+        self.configs
+            .values()
+            .any(|dev_tasks| dev_tasks.contains(task_id))
+    }
 }
diff --git a/crates/turborepo-lib/src/task_graph/visitor/command.rs b/crates/turborepo-lib/src/task_graph/visitor/command.rs
index b211d57c60e92..17b2b315dff46 100644
--- a/crates/turborepo-lib/src/task_graph/visitor/command.rs
+++ b/crates/turborepo-lib/src/task_graph/visitor/command.rs
@@ -61,6 +61,7 @@ pub struct PackageGraphCommandProvider<'a> {
     package_graph: &'a PackageGraph,
     package_manager_binary: Result<PathBuf, which::Error>,
     task_args: TaskArgs<'a>,
+    mfe_configs: Option<&'a MicroFrontendsConfigs>,
 }
 
 impl<'a> PackageGraphCommandProvider<'a> {
@@ -68,6 +69,7 @@ impl<'a> PackageGraphCommandProvider<'a> {
         repo_root: &'a AbsoluteSystemPath,
         package_graph: &'a PackageGraph,
         task_args: TaskArgs<'a>,
+        mfe_configs: Option<&'a MicroFrontendsConfigs>,
     ) -> Self {
         let package_manager_binary = which::which(package_graph.package_manager().command());
         Self {
@@ -75,6 +77,7 @@ impl<'a> PackageGraphCommandProvider<'a> {
             package_graph,
             package_manager_binary,
             task_args,
+            mfe_configs,
         }
     }
 
@@ -126,6 +129,15 @@ impl<'a> CommandProvider for PackageGraphCommandProvider<'a> {
         cmd.env_clear();
         cmd.envs(environment.iter());
 
+        // If the task has an associated proxy, then we indicate this to the underlying
+        // task via an env var
+        if self
+            .mfe_configs
+            .map_or(false, |mfe_configs| mfe_configs.task_has_mfe_proxy(task_id))
+        {
+            cmd.env("TURBO_TASK_HAS_MFE_PROXY", "true");
+        }
+
         // We always open stdin and the visitor will close it depending on task
         // configuration
         cmd.open_stdin();
diff --git a/crates/turborepo-lib/src/task_graph/visitor/exec.rs b/crates/turborepo-lib/src/task_graph/visitor/exec.rs
index d41a34043dadf..0ba1c2a38d2d0 100644
--- a/crates/turborepo-lib/src/task_graph/visitor/exec.rs
+++ b/crates/turborepo-lib/src/task_graph/visitor/exec.rs
@@ -50,6 +50,7 @@ impl<'a> ExecContextFactory<'a> {
             visitor.repo_root,
             &visitor.package_graph,
             visitor.run_opts.task_args(),
+            visitor.micro_frontends_configs,
         );
         let mut command_factory = CommandFactory::new();
         if let Some(micro_frontends_configs) = visitor.micro_frontends_configs {