Refactor Worker and ThreadSafeState (#3242)

* Split ThreadSafeState into State and GlobalState. State is a "local"
  state belonging to "Worker" while "GlobalState" is state shared by
  whole program.
* Update "Worker" and ops to use "GlobalState" where applicable
* Move and refactor "WorkerChannels" resource

16 files changed, 558 insertions, 415 deletions

diff --git a/cli/compilers/js.rs b/cli/compilers/js.rs
index 56c9b672e..af79690d6 100644
--- a/cli/compilers/js.rs
+++ b/cli/compilers/js.rs
@@ -2,7 +2,6 @@
 use crate::compilers::CompiledModule;
 use crate::compilers::CompiledModuleFuture;
 use crate::file_fetcher::SourceFile;
-use crate::state::ThreadSafeState;
 use std::str;
 
 pub struct JsCompiler {}
@@ -10,7 +9,6 @@ pub struct JsCompiler {}
 impl JsCompiler {
   pub fn compile_async(
     self: &Self,
-    _state: ThreadSafeState,
     source_file: &SourceFile,
   ) -> Box<CompiledModuleFuture> {
     let module = CompiledModule {
diff --git a/cli/compilers/json.rs b/cli/compilers/json.rs
index e61b38649..22a1d5f3d 100644
--- a/cli/compilers/json.rs
+++ b/cli/compilers/json.rs
@@ -2,7 +2,6 @@
 use crate::compilers::CompiledModule;
 use crate::compilers::CompiledModuleFuture;
 use crate::file_fetcher::SourceFile;
-use crate::state::ThreadSafeState;
 use deno::ErrBox;
 use regex::Regex;
 use std::str;
@@ -15,7 +14,6 @@ pub struct JsonCompiler {}
 impl JsonCompiler {
   pub fn compile_async(
     self: &Self,
-    _state: ThreadSafeState,
     source_file: &SourceFile,
   ) -> Box<CompiledModuleFuture> {
     let maybe_json_value: serde_json::Result<serde_json::Value> =
diff --git a/cli/compilers/ts.rs b/cli/compilers/ts.rs
index c2a4ccc4a..3c36f14c4 100644
--- a/cli/compilers/ts.rs
+++ b/cli/compilers/ts.rs
@@ -5,8 +5,8 @@ use crate::diagnostics::Diagnostic;
 use crate::disk_cache::DiskCache;
 use crate::file_fetcher::SourceFile;
 use crate::file_fetcher::SourceFileFetcher;
+use crate::global_state::ThreadSafeGlobalState;
 use crate::msg;
-use crate::resources;
 use crate::source_maps::SourceMapGetter;
 use crate::startup_data;
 use crate::state::*;
@@ -16,7 +16,7 @@ use deno::Buf;
 use deno::ErrBox;
 use deno::ModuleSpecifier;
 use futures::Future;
-use futures::Stream;
+use futures::IntoFuture;
 use regex::Regex;
 use std::collections::HashSet;
 use std::fs;
@@ -222,16 +222,20 @@ impl TsCompiler {
   }
 
   /// Create a new V8 worker with snapshot of TS compiler and setup compiler's runtime.
-  fn setup_worker(state: ThreadSafeState) -> Worker {
+  fn setup_worker(global_state: ThreadSafeGlobalState) -> Worker {
+    let worker_state = ThreadSafeState::new(global_state.clone(), None, true)
+      .expect("Unable to create worker state");
+
     // Count how many times we start the compiler worker.
-    state.metrics.compiler_starts.fetch_add(1, Ordering::SeqCst);
+    global_state
+      .metrics
+      .compiler_starts
+      .fetch_add(1, Ordering::SeqCst);
 
     let mut worker = Worker::new(
       "TS".to_string(),
       startup_data::compiler_isolate_init(),
-      // TODO(ry) Maybe we should use a separate state for the compiler.
-      // as was done previously.
-      state.clone(),
+      worker_state,
     );
     worker.execute("denoMain()").unwrap();
     worker.execute("workerMain()").unwrap();
@@ -241,7 +245,7 @@ impl TsCompiler {
 
   pub fn bundle_async(
     self: &Self,
-    state: ThreadSafeState,
+    global_state: ThreadSafeGlobalState,
     module_name: String,
     out_file: String,
   ) -> impl Future<Item = (), Error = ErrBox> {
@@ -253,25 +257,21 @@ impl TsCompiler {
     let root_names = vec![module_name.clone()];
     let req_msg = req(root_names, self.config.clone(), Some(out_file));
 
-    let worker = TsCompiler::setup_worker(state.clone());
-    let resource = worker.state.resource.clone();
-    let compiler_rid = resource.rid;
-    let first_msg_fut =
-      resources::post_message_to_worker(compiler_rid, req_msg)
-        .expect("Bad compiler rid")
-        .then(move |_| worker)
-        .then(move |result| {
-          if let Err(err) = result {
-            // TODO(ry) Need to forward the error instead of exiting.
-            eprintln!("{}", err.to_string());
-            std::process::exit(1);
-          }
-          debug!("Sent message to worker");
-          let stream_future =
-            resources::get_message_stream_from_worker(compiler_rid)
-              .into_future();
-          stream_future.map(|(f, _rest)| f).map_err(|(f, _rest)| f)
-        });
+    let worker = TsCompiler::setup_worker(global_state.clone());
+    let worker_ = worker.clone();
+    let first_msg_fut = worker
+      .post_message(req_msg)
+      .into_future()
+      .then(move |_| worker)
+      .then(move |result| {
+        if let Err(err) = result {
+          // TODO(ry) Need to forward the error instead of exiting.
+          eprintln!("{}", err.to_string());
+          std::process::exit(1);
+        }
+        debug!("Sent message to worker");
+        worker_.get_message()
+      });
 
     first_msg_fut.map_err(|_| panic!("not handled")).and_then(
       move |maybe_msg: Option<Buf>| {
@@ -312,7 +312,7 @@ impl TsCompiler {
   /// If compilation is required then new V8 worker is spawned with fresh TS compiler.
   pub fn compile_async(
     self: &Self,
-    state: ThreadSafeState,
+    global_state: ThreadSafeGlobalState,
     source_file: &SourceFile,
   ) -> Box<CompiledModuleFuture> {
     if self.has_compiled(&source_file.url) {
@@ -359,28 +359,26 @@ impl TsCompiler {
     let root_names = vec![module_url.to_string()];
     let req_msg = req(root_names, self.config.clone(), None);
 
-    let worker = TsCompiler::setup_worker(state.clone());
-    let compiling_job = state.progress.add("Compile", &module_url.to_string());
-    let state_ = state.clone();
-
-    let resource = worker.state.resource.clone();
-    let compiler_rid = resource.rid;
-    let first_msg_fut =
-      resources::post_message_to_worker(compiler_rid, req_msg)
-        .expect("Bad compiler rid")
-        .then(move |_| worker)
-        .then(move |result| {
-          if let Err(err) = result {
-            // TODO(ry) Need to forward the error instead of exiting.
-            eprintln!("{}", err.to_string());
-            std::process::exit(1);
-          }
-          debug!("Sent message to worker");
-          let stream_future =
-            resources::get_message_stream_from_worker(compiler_rid)
-              .into_future();
-          stream_future.map(|(f, _rest)| f).map_err(|(f, _rest)| f)
-        });
+    let worker = TsCompiler::setup_worker(global_state.clone());
+    let worker_ = worker.clone();
+    let compiling_job = global_state
+      .progress
+      .add("Compile", &module_url.to_string());
+    let global_state_ = global_state.clone();
+
+    let first_msg_fut = worker
+      .post_message(req_msg)
+      .into_future()
+      .then(move |_| worker)
+      .then(move |result| {
+        if let Err(err) = result {
+          // TODO(ry) Need to forward the error instead of exiting.
+          eprintln!("{}", err.to_string());
+          std::process::exit(1);
+        }
+        debug!("Sent message to worker");
+        worker_.get_message()
+      });
 
     let fut = first_msg_fut
       .map_err(|_| panic!("not handled"))
@@ -400,7 +398,7 @@ impl TsCompiler {
       .and_then(move |_| {
         // if we are this far it means compilation was successful and we can
         // load compiled filed from disk
-        state_
+        global_state_
           .ts_compiler
           .get_compiled_module(&source_file_.url)
           .map_err(|e| {
@@ -663,7 +661,7 @@ mod tests {
       source_code: include_bytes!("../tests/002_hello.ts").to_vec(),
     };
 
-    let mock_state = ThreadSafeState::mock(vec![
+    let mock_state = ThreadSafeGlobalState::mock(vec![
       String::from("deno"),
       String::from("hello.js"),
     ]);
@@ -696,7 +694,7 @@ mod tests {
       .unwrap()
       .to_string();
 
-    let state = ThreadSafeState::mock(vec![
+    let state = ThreadSafeGlobalState::mock(vec![
       String::from("deno"),
       p.to_string_lossy().into(),
       String::from("$deno$/bundle.js"),
diff --git a/cli/global_state.rs b/cli/global_state.rs
new file mode 100644
index 000000000..3e102cb4e
--- /dev/null
+++ b/cli/global_state.rs
@@ -0,0 +1,247 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+use crate::compilers::CompiledModule;
+use crate::compilers::JsCompiler;
+use crate::compilers::JsonCompiler;
+use crate::compilers::TsCompiler;
+use crate::deno_dir;
+use crate::deno_error::permission_denied;
+use crate::file_fetcher::SourceFileFetcher;
+use crate::flags;
+use crate::lockfile::Lockfile;
+use crate::metrics::Metrics;
+use crate::msg;
+use crate::permissions::DenoPermissions;
+use crate::progress::Progress;
+use deno::ErrBox;
+use deno::ModuleSpecifier;
+use futures::Future;
+use std;
+use std::env;
+use std::ops::Deref;
+use std::str;
+use std::sync::Arc;
+use std::sync::Mutex;
+
+/// Holds state of the program and can be accessed by V8 isolate.
+pub struct ThreadSafeGlobalState(Arc<GlobalState>);
+
+/// This structure represents state of single "deno" program.
+///
+/// It is shared by all created workers (thus V8 isolates).
+#[cfg_attr(feature = "cargo-clippy", allow(stutter))]
+pub struct GlobalState {
+  /// Vector of CLI arguments - these are user script arguments, all Deno specific flags are removed.
+  pub argv: Vec<String>,
+  /// Flags parsed from `argv` contents.
+  pub flags: flags::DenoFlags,
+  /// Entry script parsed from CLI arguments.
+  pub main_module: Option<ModuleSpecifier>,
+  /// Permissions parsed from `flags`.
+  pub permissions: DenoPermissions,
+  pub dir: deno_dir::DenoDir,
+  pub metrics: Metrics,
+  pub progress: Progress,
+  pub file_fetcher: SourceFileFetcher,
+  pub js_compiler: JsCompiler,
+  pub json_compiler: JsonCompiler,
+  pub ts_compiler: TsCompiler,
+  pub lockfile: Option<Mutex<Lockfile>>,
+}
+
+impl Clone for ThreadSafeGlobalState {
+  fn clone(&self) -> Self {
+    ThreadSafeGlobalState(self.0.clone())
+  }
+}
+
+impl Deref for ThreadSafeGlobalState {
+  type Target = Arc<GlobalState>;
+  fn deref(&self) -> &Self::Target {
+    &self.0
+  }
+}
+
+impl ThreadSafeGlobalState {
+  pub fn new(
+    flags: flags::DenoFlags,
+    argv_rest: Vec<String>,
+    progress: Progress,
+  ) -> Result<Self, ErrBox> {
+    let custom_root = env::var("DENO_DIR").map(String::into).ok();
+    let dir = deno_dir::DenoDir::new(custom_root)?;
+
+    let file_fetcher = SourceFileFetcher::new(
+      dir.deps_cache.clone(),
+      progress.clone(),
+      !flags.reload,
+      flags.cache_blacklist.clone(),
+      flags.no_fetch,
+    )?;
+
+    let ts_compiler = TsCompiler::new(
+      file_fetcher.clone(),
+      dir.gen_cache.clone(),
+      !flags.reload,
+      flags.config_path.clone(),
+    )?;
+
+    let main_module: Option<ModuleSpecifier> = if argv_rest.len() <= 1 {
+      None
+    } else {
+      let root_specifier = argv_rest[1].clone();
+      Some(ModuleSpecifier::resolve_url_or_path(&root_specifier)?)
+    };
+
+    // Note: reads lazily from disk on first call to lockfile.check()
+    let lockfile = if let Some(filename) = &flags.lock {
+      Some(Mutex::new(Lockfile::new(filename.to_string())))
+    } else {
+      None
+    };
+
+    let state = GlobalState {
+      main_module,
+      dir,
+      argv: argv_rest,
+      permissions: DenoPermissions::from_flags(&flags),
+      flags,
+      metrics: Metrics::default(),
+      progress,
+      file_fetcher,
+      ts_compiler,
+      js_compiler: JsCompiler {},
+      json_compiler: JsonCompiler {},
+      lockfile,
+    };
+
+    Ok(ThreadSafeGlobalState(Arc::new(state)))
+  }
+
+  pub fn fetch_compiled_module(
+    self: &Self,
+    module_specifier: &ModuleSpecifier,
+  ) -> impl Future<Item = CompiledModule, Error = ErrBox> {
+    let state1 = self.clone();
+    let state2 = self.clone();
+
+    self
+      .file_fetcher
+      .fetch_source_file_async(&module_specifier)
+      .and_then(move |out| match out.media_type {
+        msg::MediaType::Unknown => state1.js_compiler.compile_async(&out),
+        msg::MediaType::Json => state1.json_compiler.compile_async(&out),
+        msg::MediaType::TypeScript
+        | msg::MediaType::TSX
+        | msg::MediaType::JSX => {
+          state1.ts_compiler.compile_async(state1.clone(), &out)
+        }
+        msg::MediaType::JavaScript => {
+          if state1.ts_compiler.compile_js {
+            state1.ts_compiler.compile_async(state1.clone(), &out)
+          } else {
+            state1.js_compiler.compile_async(&out)
+          }
+        }
+      })
+      .and_then(move |compiled_module| {
+        if let Some(ref lockfile) = state2.lockfile {
+          let mut g = lockfile.lock().unwrap();
+          if state2.flags.lock_write {
+            g.insert(&compiled_module);
+          } else if !g.check(&compiled_module)? {
+            eprintln!(
+              "Subresource integrety check failed --lock={}\n{}",
+              g.filename, compiled_module.name
+            );
+            std::process::exit(10);
+          }
+        }
+        Ok(compiled_module)
+      })
+  }
+
+  #[inline]
+  pub fn check_read(&self, filename: &str) -> Result<(), ErrBox> {
+    self.permissions.check_read(filename)
+  }
+
+  #[inline]
+  pub fn check_write(&self, filename: &str) -> Result<(), ErrBox> {
+    self.permissions.check_write(filename)
+  }
+
+  #[inline]
+  pub fn check_env(&self) -> Result<(), ErrBox> {
+    self.permissions.check_env()
+  }
+
+  #[inline]
+  pub fn check_net(&self, hostname: &str, port: u16) -> Result<(), ErrBox> {
+    self.permissions.check_net(hostname, port)
+  }
+
+  #[inline]
+  pub fn check_net_url(&self, url: &url::Url) -> Result<(), ErrBox> {
+    self.permissions.check_net_url(url)
+  }
+
+  #[inline]
+  pub fn check_run(&self) -> Result<(), ErrBox> {
+    self.permissions.check_run()
+  }
+
+  pub fn check_dyn_import(
+    self: &Self,
+    module_specifier: &ModuleSpecifier,
+  ) -> Result<(), ErrBox> {
+    let u = module_specifier.as_url();
+    match u.scheme() {
+      "http" | "https" => {
+        self.check_net_url(u)?;
+        Ok(())
+      }
+      "file" => {
+        let filename = u
+          .to_file_path()
+          .unwrap()
+          .into_os_string()
+          .into_string()
+          .unwrap();
+        self.check_read(&filename)?;
+        Ok(())
+      }
+      _ => Err(permission_denied()),
+    }
+  }
+
+  #[cfg(test)]
+  pub fn mock(argv: Vec<String>) -> ThreadSafeGlobalState {
+    ThreadSafeGlobalState::new(
+      flags::DenoFlags::default(),
+      argv,
+      Progress::new(),
+    )
+    .unwrap()
+  }
+}
+
+#[test]
+fn thread_safe() {
+  fn f<S: Send + Sync>(_: S) {}
+  f(ThreadSafeGlobalState::mock(vec![
+    String::from("./deno"),
+    String::from("hello.js"),
+  ]));
+}
+
+#[test]
+fn import_map_given_for_repl() {
+  let _result = ThreadSafeGlobalState::new(
+    flags::DenoFlags {
+      import_map_path: Some("import_map.json".to_string()),
+      ..flags::DenoFlags::default()
+    },
+    vec![String::from("./deno")],
+    Progress::new(),
+  );
+}
diff --git a/cli/js/workers.ts b/cli/js/workers.ts
index 281fe619f..37061063f 100644
--- a/cli/js/workers.ts
+++ b/cli/js/workers.ts
@@ -65,7 +65,6 @@ export function postMessage(data: any): void {
 export async function getMessage(): Promise<any> {
   log("getMessage");
   const res = await sendAsync(dispatch.OP_WORKER_GET_MESSAGE);
-
   if (res.data != null) {
     return decodeMessage(new Uint8Array(res.data));
   } else {
diff --git a/cli/lib.rs b/cli/lib.rs
index 4f5319508..b6922c591 100644
--- a/cli/lib.rs
+++ b/cli/lib.rs
@@ -15,6 +15,7 @@ extern crate nix;
 extern crate rand;
 extern crate serde;
 extern crate serde_derive;
+extern crate tokio;
 extern crate url;
 
 mod checksum;
@@ -28,12 +29,14 @@ mod file_fetcher;
 pub mod flags;
 pub mod fmt_errors;
 mod fs;
+mod global_state;
 mod global_timer;
 mod http_body;
 mod http_util;
 mod import_map;
 mod js;
 mod lockfile;
+mod metrics;
 pub mod msg;
 pub mod ops;
 pub mod permissions;
@@ -55,6 +58,7 @@ pub mod worker;
 
 use crate::deno_error::js_check;
 use crate::deno_error::print_err_and_exit;
+use crate::global_state::ThreadSafeGlobalState;
 use crate::progress::Progress;
 use crate::state::ThreadSafeState;
 use crate::worker::Worker;
@@ -97,11 +101,13 @@ impl log::Log for Logger {
 fn create_worker_and_state(
   flags: DenoFlags,
   argv: Vec<String>,
-) -> (Worker, ThreadSafeState) {
+) -> (Worker, ThreadSafeGlobalState) {
   use crate::shell::Shell;
   use std::sync::Arc;
   use std::sync::Mutex;
+
   let shell = Arc::new(Mutex::new(Shell::new()));
+
   let progress = Progress::new();
   progress.set_callback(move |_done, _completed, _total, status, msg| {
     if !status.is_empty() {
@@ -109,17 +115,23 @@ fn create_worker_and_state(
       s.status(status, msg).expect("shell problem");
     }
   });
-  // TODO(kevinkassimo): maybe make include_deno_namespace also configurable?
-  let state = ThreadSafeState::new(flags, argv, progress, true)
+
+  let global_state = ThreadSafeGlobalState::new(flags, argv, progress)
     .map_err(deno_error::print_err_and_exit)
     .unwrap();
-  let worker = Worker::new(
-    "main".to_string(),
-    startup_data::deno_isolate_init(),
-    state.clone(),
-  );
 
-  (worker, state)
+  let state = ThreadSafeState::new(
+    global_state.clone(),
+    global_state.main_module.clone(),
+    true,
+  )
+  .map_err(deno_error::print_err_and_exit)
+  .unwrap();
+
+  let worker =
+    Worker::new("main".to_string(), startup_data::deno_isolate_init(), state);
+
+  (worker, global_state)
 }
 
 fn types_command() {
@@ -128,7 +140,7 @@ fn types_command() {
 }
 
 fn print_cache_info(worker: Worker) {
-  let state = worker.state;
+  let state = &worker.state.global_state;
 
   println!(
     "{} {:?}",
@@ -151,10 +163,11 @@ pub fn print_file_info(
   worker: Worker,
   module_specifier: &ModuleSpecifier,
 ) -> impl Future<Item = Worker, Error = ()> {
+  let global_state_ = worker.state.global_state.clone();
   let state_ = worker.state.clone();
   let module_specifier_ = module_specifier.clone();
 
-  state_
+  global_state_
     .file_fetcher
     .fetch_source_file_async(&module_specifier)
     .map_err(|err| println!("{}", err))
@@ -171,7 +184,7 @@ pub fn print_file_info(
         msg::enum_name_media_type(out.media_type)
       );
 
-      state_
+      global_state_
         .clone()
         .fetch_compiled_module(&module_specifier_)
         .map_err(|e| {
@@ -182,9 +195,9 @@ pub fn print_file_info(
         .and_then(move |compiled| {
           if out.media_type == msg::MediaType::TypeScript
             || (out.media_type == msg::MediaType::JavaScript
-              && state_.ts_compiler.compile_js)
+              && global_state_.ts_compiler.compile_js)
           {
-            let compiled_source_file = state_
+            let compiled_source_file = global_state_
               .ts_compiler
               .get_compiled_source_file(&out.url)
               .unwrap();
@@ -196,7 +209,7 @@ pub fn print_file_info(
             );
           }
 
-          if let Ok(source_map) = state_
+          if let Ok(source_map) = global_state_
             .clone()
             .ts_compiler
             .get_source_map_file(&module_specifier_)
@@ -209,7 +222,7 @@ pub fn print_file_info(
           }
 
           if let Some(deps) =
-            worker.state.modules.lock().unwrap().deps(&compiled.name)
+            state_.modules.lock().unwrap().deps(&compiled.name)
           {
             println!("{}{}", colors::bold("deps:\n".to_string()), deps.name);
             if let Some(ref depsdeps) = deps.deps {
@@ -236,7 +249,7 @@ fn info_command(flags: DenoFlags, argv: Vec<String>) {
     return print_cache_info(worker);
   }
 
-  let main_module = state.main_module().unwrap();
+  let main_module = state.main_module.as_ref().unwrap().clone();
   let main_future = lazy(move || {
     // Setup runtime.
     js_check(worker.execute("denoMain()"));
@@ -259,7 +272,7 @@ fn info_command(flags: DenoFlags, argv: Vec<String>) {
 fn fetch_command(flags: DenoFlags, argv: Vec<String>) {
   let (mut worker, state) = create_worker_and_state(flags, argv.clone());
 
-  let main_module = state.main_module().unwrap();
+  let main_module = state.main_module.as_ref().unwrap().clone();
   let main_future = lazy(move || {
     // Setup runtime.
     js_check(worker.execute("denoMain()"));
@@ -307,7 +320,7 @@ fn eval_command(flags: DenoFlags, argv: Vec<String>) {
 fn bundle_command(flags: DenoFlags, argv: Vec<String>) {
   let (worker, state) = create_worker_and_state(flags, argv);
 
-  let main_module = state.main_module().unwrap();
+  let main_module = state.main_module.as_ref().unwrap().clone();
   assert!(state.argv.len() >= 3);
   let out_file = state.argv[2].clone();
   debug!(">>>>> bundle_async START");
@@ -353,7 +366,7 @@ fn run_script(flags: DenoFlags, argv: Vec<String>) {
   let use_current_thread = flags.current_thread;
   let (mut worker, state) = create_worker_and_state(flags, argv);
 
-  let main_module = state.main_module().unwrap();
+  let main_module = state.main_module.as_ref().unwrap().clone();
   // Normal situation of executing a module.
   let main_future = lazy(move || {
     // Setup runtime.
diff --git a/cli/metrics.rs b/cli/metrics.rs
new file mode 100644
index 000000000..d1e7567b9
--- /dev/null
+++ b/cli/metrics.rs
@@ -0,0 +1,12 @@
+use std::sync::atomic::AtomicUsize;
+
+#[derive(Default)]
+pub struct Metrics {
+  pub ops_dispatched: AtomicUsize,
+  pub ops_completed: AtomicUsize,
+  pub bytes_sent_control: AtomicUsize,
+  pub bytes_sent_data: AtomicUsize,
+  pub bytes_received: AtomicUsize,
+  pub resolve_count: AtomicUsize,
+  pub compiler_starts: AtomicUsize,
+}
diff --git a/cli/ops/compiler.rs b/cli/ops/compiler.rs
index 720eb65fc..e7d38f364 100644
--- a/cli/ops/compiler.rs
+++ b/cli/ops/compiler.rs
@@ -4,6 +4,7 @@ use crate::futures::future::join_all;
 use crate::futures::Future;
 use crate::ops::json_op;
 use crate::state::ThreadSafeState;
+use deno::Loader;
 use deno::*;
 
 pub fn init(i: &mut Isolate, s: &ThreadSafeState) {
@@ -36,7 +37,7 @@ fn op_cache(
   let module_specifier = ModuleSpecifier::resolve_url(&args.module_id)
     .expect("Should be valid module specifier");
 
-  state.ts_compiler.cache_compiler_output(
+  state.global_state.ts_compiler.cache_compiler_output(
     &module_specifier,
     &args.extension,
     &args.contents,
@@ -67,6 +68,7 @@ fn op_fetch_source_files(
     let resolved_specifier =
       state.resolve(specifier, &args.referrer, false, is_dyn_import)?;
     let fut = state
+      .global_state
       .file_fetcher
       .fetch_source_file_async(&resolved_specifier);
     futures.push(fut);
diff --git a/cli/ops/errors.rs b/cli/ops/errors.rs
index 2d786b97d..3d94c05c4 100644
--- a/cli/ops/errors.rs
+++ b/cli/ops/errors.rs
@@ -30,7 +30,7 @@ fn op_format_error(
   _zero_copy: Option<PinnedBuf>,
 ) -> Result<JsonOp, ErrBox> {
   let args: FormatErrorArgs = serde_json::from_value(args)?;
-  let error = JSError::from_json(&args.error, &state.ts_compiler);
+  let error = JSError::from_json(&args.error, &state.global_state.ts_compiler);
 
   Ok(JsonOp::Sync(json!({
     "error": error.to_string(),
@@ -57,7 +57,7 @@ fn op_apply_source_map(
     args.line.into(),
     args.column.into(),
     &mut mappings_map,
-    &state.ts_compiler,
+    &state.global_state.ts_compiler,
   );
 
   Ok(JsonOp::Sync(json!({
diff --git a/cli/ops/os.rs b/cli/ops/os.rs
index c50b8eedb..78fd940de 100644
--- a/cli/ops/os.rs
+++ b/cli/ops/os.rs
@@ -7,7 +7,6 @@ use crate::state::ThreadSafeState;
 use crate::version;
 use atty;
 use deno::*;
-use log;
 use std::collections::HashMap;
 use std::env;
 use sys_info;
@@ -40,16 +39,15 @@ fn op_start(
   _args: Value,
   _zero_copy: Option<PinnedBuf>,
 ) -> Result<JsonOp, ErrBox> {
+  let gs = &state.global_state;
+
   Ok(JsonOp::Sync(json!({
     "cwd": deno_fs::normalize_path(&env::current_dir().unwrap()),
     "pid": std::process::id(),
-    "argv": state.argv,
-    "mainModule": state.main_module().map(|x| x.as_str().to_string()),
-    "debugFlag": state
-      .flags
-      .log_level
-      .map_or(false, |l| l == log::Level::Debug),
-    "versionFlag": state.flags.version,
+    "argv": gs.argv,
+    "mainModule": gs.main_module.as_ref().map(|x| x.to_string()),
+    "debugFlag": gs.flags.log_level.map_or(false, |l| l == log::Level::Debug),
+    "versionFlag": gs.flags.version,
     "v8Version": version::v8(),
     "denoVersion": version::DENO,
     "tsVersion": version::TYPESCRIPT,
diff --git a/cli/ops/repl.rs b/cli/ops/repl.rs
index 6644ab159..4a3ba68d4 100644
--- a/cli/ops/repl.rs
+++ b/cli/ops/repl.rs
@@ -44,7 +44,8 @@ fn op_repl_start(
   let args: ReplStartArgs = serde_json::from_value(args)?;
 
   debug!("op_repl_start {}", args.history_file);
-  let history_path = repl::history_path(&state.dir, &args.history_file);
+  let history_path =
+    repl::history_path(&state.global_state.dir, &args.history_file);
   let repl = repl::Repl::new(history_path);
   let resource = ReplResource(Arc::new(Mutex::new(repl)));
   let mut table = resources::lock_resource_table();
diff --git a/cli/ops/workers.rs b/cli/ops/workers.rs
index 809aa5d9b..f6dcf8042 100644
--- a/cli/ops/workers.rs
+++ b/cli/ops/workers.rs
@@ -4,7 +4,6 @@ use crate::deno_error::js_check;
 use crate::deno_error::DenoError;
 use crate::deno_error::ErrorKind;
 use crate::ops::json_op;
-use crate::resources;
 use crate::startup_data;
 use crate::state::ThreadSafeState;
 use crate::worker::Worker;
@@ -12,6 +11,7 @@ use deno::*;
 use futures;
 use futures::Async;
 use futures::Future;
+use futures::IntoFuture;
 use futures::Sink;
 use futures::Stream;
 use std;
@@ -48,18 +48,17 @@ pub fn init(i: &mut Isolate, s: &ThreadSafeState) {
 }
 
 struct GetMessageFuture {
-  pub state: ThreadSafeState,
+  state: ThreadSafeState,
 }
 
 impl Future for GetMessageFuture {
   type Item = Option<Buf>;
-  type Error = ();
+  type Error = ErrBox;
 
   fn poll(&mut self) -> Result<Async<Self::Item>, Self::Error> {
-    let mut wc = self.state.worker_channels.lock().unwrap();
-    wc.1
-      .poll()
-      .map_err(|err| panic!("worker_channel recv err {:?}", err))
+    let mut channels = self.state.worker_channels.lock().unwrap();
+    let receiver = &mut channels.receiver;
+    receiver.poll().map_err(ErrBox::from)
   }
 }
 
@@ -93,12 +92,10 @@ fn op_worker_post_message(
   data: Option<PinnedBuf>,
 ) -> Result<JsonOp, ErrBox> {
   let d = Vec::from(data.unwrap().as_ref()).into_boxed_slice();
-
-  let tx = {
-    let wc = state.worker_channels.lock().unwrap();
-    wc.0.clone()
-  };
-  tx.send(d)
+  let mut channels = state.worker_channels.lock().unwrap();
+  let sender = &mut channels.sender;
+  sender
+    .send(d)
     .wait()
     .map_err(|e| DenoError::new(ErrorKind::Other, e.to_string()))?;
 
@@ -132,28 +129,23 @@ fn op_create_worker(
 
   let parent_state = state.clone();
 
+  // TODO(bartlomieju): Isn't this wrong?
   let mut module_specifier = ModuleSpecifier::resolve_url_or_path(specifier)?;
-
-  let mut child_argv = parent_state.argv.clone();
-
   if !has_source_code {
-    if let Some(module) = state.main_module() {
-      module_specifier =
-        ModuleSpecifier::resolve_import(specifier, &module.to_string())?;
-      child_argv[1] = module_specifier.to_string();
+    if let Some(referrer) = parent_state.main_module.as_ref() {
+      let referrer = referrer.clone().to_string();
+      module_specifier = ModuleSpecifier::resolve_import(specifier, &referrer)?;
     }
   }
 
   let child_state = ThreadSafeState::new(
-    parent_state.flags.clone(),
-    child_argv,
-    parent_state.progress.clone(),
+    state.global_state.clone(),
+    Some(module_specifier.clone()),
     include_deno_namespace,
   )?;
-  let rid = child_state.resource.rid;
+  let rid = child_state.rid;
   let name = format!("USER-WORKER-{}", specifier);
   let deno_main_call = format!("denoMain({})", include_deno_namespace);
-
   let mut worker =
     Worker::new(name, startup_data::deno_isolate_init(), child_state);
   js_check(worker.execute(&deno_main_call));
@@ -201,9 +193,8 @@ fn op_host_get_worker_closed(
     worker.clone()
   };
 
-  let op = Box::new(
-    shared_worker_future.then(move |_result| futures::future::ok(json!({}))),
-  );
+  let op =
+    shared_worker_future.then(move |_result| futures::future::ok(json!({})));
 
   Ok(JsonOp::Async(Box::new(op)))
 }
@@ -222,7 +213,7 @@ fn op_host_get_message(
   let args: HostGetMessageArgs = serde_json::from_value(args)?;
 
   let rid = args.rid as u32;
-  let op = resources::get_message_from_worker(rid)
+  let op = Worker::get_message_from_resource(rid)
     .map_err(move |_| -> ErrBox { unimplemented!() })
     .and_then(move |maybe_buf| {
       futures::future::ok(json!({
@@ -250,7 +241,9 @@ fn op_host_post_message(
 
   let d = Vec::from(data.unwrap().as_ref()).into_boxed_slice();
 
-  resources::post_message_to_worker(rid, d)?
+  // TODO: rename to post_message_to_child(rid, d)
+  Worker::post_message_to_resource(rid, d)
+    .into_future()
     .wait()
     .map_err(|e| DenoError::new(ErrorKind::Other, e.to_string()))?;
 
diff --git a/cli/permissions.rs b/cli/permissions.rs
index af4c960d7..1a470f551 100644
--- a/cli/permissions.rs
+++ b/cli/permissions.rs
@@ -52,7 +52,7 @@ impl fmt::Display for PermissionAccessorState {
   }
 }
 
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct PermissionAccessor {
   state: Arc<AtomicUsize>,
 }
@@ -110,7 +110,7 @@ impl Default for PermissionAccessor {
   }
 }
 
-#[derive(Debug, Default)]
+#[derive(Clone, Debug, Default)]
 pub struct DenoPermissions {
   // Keep in sync with cli/js/permissions.ts
   pub allow_read: PermissionAccessor,
diff --git a/cli/resources.rs b/cli/resources.rs
index 4df4e1798..ba7795f5d 100644
--- a/cli/resources.rs
+++ b/cli/resources.rs
@@ -11,9 +11,6 @@
 use crate::deno_error;
 use crate::deno_error::bad_resource;
 use crate::http_body::HttpBody;
-use crate::state::WorkerChannels;
-
-use deno::Buf;
 use deno::ErrBox;
 pub use deno::Resource as CoreResource;
 pub use deno::ResourceId;
@@ -22,8 +19,6 @@ use deno::ResourceTable;
 use futures;
 use futures::Future;
 use futures::Poll;
-use futures::Sink;
-use futures::Stream;
 use reqwest::r#async::Decoder as ReqwestDecoder;
 use std;
 use std::io::{Error, Read, Seek, SeekFrom, Write};
@@ -34,7 +29,6 @@ use std::sync::MutexGuard;
 use tokio;
 use tokio::io::{AsyncRead, AsyncWrite};
 use tokio::net::TcpStream;
-use tokio::sync::mpsc;
 use tokio_process;
 use tokio_rustls::client::TlsStream as ClientTlsStream;
 use tokio_rustls::server::TlsStream as ServerTlsStream;
@@ -101,7 +95,6 @@ enum CliResource {
   ChildStdin(tokio_process::ChildStdin),
   ChildStdout(tokio_process::ChildStdout),
   ChildStderr(tokio_process::ChildStderr),
-  Worker(WorkerChannels),
 }
 
 impl CoreResource for CliResource {
@@ -133,7 +126,6 @@ impl CoreResource for CliResource {
       CliResource::ChildStdin(_) => "childStdin",
       CliResource::ChildStdout(_) => "childStdout",
       CliResource::ChildStderr(_) => "childStderr",
-      CliResource::Worker(_) => "worker",
     }
   }
 }
@@ -372,78 +364,6 @@ pub fn add_reqwest_body(body: ReqwestDecoder) -> Resource {
   Resource { rid }
 }
 
-pub fn add_worker(wc: WorkerChannels) -> Resource {
-  let mut table = lock_resource_table();
-  let rid = table.add(Box::new(CliResource::Worker(wc)));
-  Resource { rid }
-}
-
-/// Post message to worker as a host or privilged overlord
-pub fn post_message_to_worker(
-  rid: ResourceId,
-  buf: Buf,
-) -> Result<futures::sink::Send<mpsc::Sender<Buf>>, ErrBox> {
-  let mut table = lock_resource_table();
-  let repr = table.get_mut::<CliResource>(rid).ok_or_else(bad_resource)?;
-  match repr {
-    CliResource::Worker(ref mut wc) => {
-      let sender = wc.0.clone();
-      Ok(sender.send(buf))
-    }
-    _ => Err(bad_resource()),
-  }
-}
-
-pub struct WorkerReceiver {
-  rid: ResourceId,
-}
-
-// Invert the dumbness that tokio_process causes by making Child itself a future.
-impl Future for WorkerReceiver {
-  type Item = Option<Buf>;
-  type Error = ErrBox;
-
-  fn poll(&mut self) -> Poll<Option<Buf>, ErrBox> {
-    let mut table = lock_resource_table();
-    let repr = table
-      .get_mut::<CliResource>(self.rid)
-      .ok_or_else(bad_resource)?;
-    match repr {
-      CliResource::Worker(ref mut wc) => wc.1.poll().map_err(ErrBox::from),
-      _ => Err(bad_resource()),
-    }
-  }
-}
-
-pub fn get_message_from_worker(rid: ResourceId) -> WorkerReceiver {
-  WorkerReceiver { rid }
-}
-
-pub struct WorkerReceiverStream {
-  rid: ResourceId,
-}
-
-// Invert the dumbness that tokio_process causes by making Child itself a future.
-impl Stream for WorkerReceiverStream {
-  type Item = Buf;
-  type Error = ErrBox;
-
-  fn poll(&mut self) -> Poll<Option<Buf>, ErrBox> {
-    let mut table = lock_resource_table();
-    let repr = table
-      .get_mut::<CliResource>(self.rid)
-      .ok_or_else(bad_resource)?;
-    match repr {
-      CliResource::Worker(ref mut wc) => wc.1.poll().map_err(ErrBox::from),
-      _ => Err(bad_resource()),
-    }
-  }
-}
-
-pub fn get_message_stream_from_worker(rid: ResourceId) -> WorkerReceiverStream {
-  WorkerReceiverStream { rid }
-}
-
 pub struct ChildResources {
   pub child_rid: Option<ResourceId>,
   pub stdin_rid: Option<ResourceId>,
diff --git a/cli/state.rs b/cli/state.rs
index 1f44f254f..544c199b8 100644
--- a/cli/state.rs
+++ b/cli/state.rs
@@ -1,22 +1,15 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
-use crate::compilers::CompiledModule;
-use crate::compilers::JsCompiler;
-use crate::compilers::JsonCompiler;
-use crate::compilers::TsCompiler;
-use crate::deno_dir;
 use crate::deno_error::permission_denied;
-use crate::file_fetcher::SourceFileFetcher;
-use crate::flags;
+use crate::global_state::ThreadSafeGlobalState;
 use crate::global_timer::GlobalTimer;
 use crate::import_map::ImportMap;
-use crate::lockfile::Lockfile;
-use crate::msg;
+use crate::metrics::Metrics;
 use crate::ops::JsonOp;
 use crate::permissions::DenoPermissions;
-use crate::progress::Progress;
 use crate::resources;
 use crate::resources::ResourceId;
 use crate::worker::Worker;
+use crate::worker::WorkerChannels;
 use deno::Buf;
 use deno::CoreOp;
 use deno::ErrBox;
@@ -31,31 +24,18 @@ use rand::SeedableRng;
 use serde_json::Value;
 use std;
 use std::collections::HashMap;
-use std::env;
 use std::ops::Deref;
 use std::str;
-use std::sync::atomic::{AtomicUsize, Ordering};
+use std::sync::atomic::Ordering;
 use std::sync::Arc;
 use std::sync::Mutex;
 use std::time::Instant;
 use tokio::sync::mpsc as async_mpsc;
 
-pub type WorkerSender = async_mpsc::Sender<Buf>;
-pub type WorkerReceiver = async_mpsc::Receiver<Buf>;
-pub type WorkerChannels = (WorkerSender, WorkerReceiver);
+// TODO: hold references to concrete Workers instead of shared futures of
+// those workers?
 pub type UserWorkerTable = HashMap<ResourceId, Shared<Worker>>;
 
-#[derive(Default)]
-pub struct Metrics {
-  pub ops_dispatched: AtomicUsize,
-  pub ops_completed: AtomicUsize,
-  pub bytes_sent_control: AtomicUsize,
-  pub bytes_sent_data: AtomicUsize,
-  pub bytes_received: AtomicUsize,
-  pub resolve_count: AtomicUsize,
-  pub compiler_starts: AtomicUsize,
-}
-
 /// Isolate cannot be passed between threads but ThreadSafeState can.
 /// ThreadSafeState satisfies Send and Sync. So any state that needs to be
 /// accessed outside the main V8 thread should be inside ThreadSafeState.
@@ -63,34 +43,22 @@ pub struct ThreadSafeState(Arc<State>);
 
 #[cfg_attr(feature = "cargo-clippy", allow(stutter))]
 pub struct State {
+  pub global_state: ThreadSafeGlobalState,
   pub modules: Arc<Mutex<deno::Modules>>,
-  pub main_module: Option<ModuleSpecifier>,
-  pub dir: deno_dir::DenoDir,
-  pub argv: Vec<String>,
   pub permissions: DenoPermissions,
-  pub flags: flags::DenoFlags,
+  pub main_module: Option<ModuleSpecifier>,
+  pub worker_channels: Mutex<WorkerChannels>,
   /// When flags contains a `.import_map_path` option, the content of the
   /// import map file will be resolved and set.
   pub import_map: Option<ImportMap>,
   pub metrics: Metrics,
-  pub worker_channels: Mutex<WorkerChannels>,
   pub global_timer: Mutex<GlobalTimer>,
   pub workers: Mutex<UserWorkerTable>,
   pub start_time: Instant,
   /// A reference to this worker's resource.
-  pub resource: resources::Resource,
-  /// Reference to global progress bar.
-  pub progress: Progress,
+  pub rid: ResourceId,
   pub seeded_rng: Option<Mutex<StdRng>>,
-
-  pub file_fetcher: SourceFileFetcher,
-  pub js_compiler: JsCompiler,
-  pub json_compiler: JsonCompiler,
-  pub ts_compiler: TsCompiler,
-
   pub include_deno_namespace: bool,
-
-  pub lockfile: Option<Mutex<Lockfile>>,
 }
 
 impl Clone for ThreadSafeState {
@@ -195,158 +163,74 @@ impl Loader for ThreadSafeState {
   ) -> Box<deno::SourceCodeInfoFuture> {
     self.metrics.resolve_count.fetch_add(1, Ordering::SeqCst);
     let module_url_specified = module_specifier.to_string();
-    Box::new(self.fetch_compiled_module(module_specifier).map(
-      |compiled_module| deno::SourceCodeInfo {
+    let fut = self
+      .global_state
+      .fetch_compiled_module(module_specifier)
+      .map(|compiled_module| deno::SourceCodeInfo {
         // Real module name, might be different from initial specifier
         // due to redirections.
         code: compiled_module.code,
         module_url_specified,
         module_url_found: compiled_module.name,
-      },
-    ))
+      });
+
+    Box::new(fut)
   }
 }
 
 impl ThreadSafeState {
   pub fn new(
-    flags: flags::DenoFlags,
-    argv_rest: Vec<String>,
-    progress: Progress,
+    global_state: ThreadSafeGlobalState,
+    main_module: Option<ModuleSpecifier>,
     include_deno_namespace: bool,
   ) -> Result<Self, ErrBox> {
-    let custom_root = env::var("DENO_DIR").map(String::into).ok();
-
     let (worker_in_tx, worker_in_rx) = async_mpsc::channel::<Buf>(1);
     let (worker_out_tx, worker_out_rx) = async_mpsc::channel::<Buf>(1);
-    let internal_channels = (worker_out_tx, worker_in_rx);
-    let external_channels = (worker_in_tx, worker_out_rx);
-    let resource = resources::add_worker(external_channels);
-
-    let dir = deno_dir::DenoDir::new(custom_root)?;
-
-    let file_fetcher = SourceFileFetcher::new(
-      dir.deps_cache.clone(),
-      progress.clone(),
-      !flags.reload,
-      flags.cache_blacklist.clone(),
-      flags.no_fetch,
-    )?;
-
-    let ts_compiler = TsCompiler::new(
-      file_fetcher.clone(),
-      dir.gen_cache.clone(),
-      !flags.reload,
-      flags.config_path.clone(),
-    )?;
-
-    let main_module: Option<ModuleSpecifier> = if argv_rest.len() <= 1 {
-      None
-    } else {
-      let root_specifier = argv_rest[1].clone();
-      Some(ModuleSpecifier::resolve_url_or_path(&root_specifier)?)
+    let internal_channels = WorkerChannels {
+      sender: worker_out_tx,
+      receiver: worker_in_rx,
     };
-
-    let import_map: Option<ImportMap> = match &flags.import_map_path {
-      None => None,
-      Some(file_path) => Some(ImportMap::load(file_path)?),
+    let external_channels = WorkerChannels {
+      sender: worker_in_tx,
+      receiver: worker_out_rx,
     };
 
-    let mut seeded_rng = None;
-    if let Some(seed) = flags.seed {
-      seeded_rng = Some(Mutex::new(StdRng::seed_from_u64(seed)));
-    };
+    let mut table = resources::lock_resource_table();
+    let rid = table.add(Box::new(external_channels));
 
-    let modules = Arc::new(Mutex::new(deno::Modules::new()));
+    let import_map: Option<ImportMap> =
+      match global_state.flags.import_map_path.as_ref() {
+        None => None,
+        Some(file_path) => Some(ImportMap::load(file_path)?),
+      };
 
-    // Note: reads lazily from disk on first call to lockfile.check()
-    let lockfile = if let Some(filename) = &flags.lock {
-      Some(Mutex::new(Lockfile::new(filename.to_string())))
-    } else {
-      None
+    let seeded_rng = match global_state.flags.seed {
+      Some(seed) => Some(Mutex::new(StdRng::seed_from_u64(seed))),
+      None => None,
     };
 
+    let modules = Arc::new(Mutex::new(deno::Modules::new()));
+    let permissions = global_state.permissions.clone();
+
     let state = State {
-      main_module,
+      global_state,
       modules,
-      dir,
-      argv: argv_rest,
-      permissions: DenoPermissions::from_flags(&flags),
-      flags,
+      main_module,
+      permissions,
       import_map,
-      metrics: Metrics::default(),
       worker_channels: Mutex::new(internal_channels),
+      metrics: Metrics::default(),
       global_timer: Mutex::new(GlobalTimer::new()),
       workers: Mutex::new(UserWorkerTable::new()),
       start_time: Instant::now(),
-      resource,
-      progress,
+      rid,
       seeded_rng,
-      file_fetcher,
-      ts_compiler,
-      js_compiler: JsCompiler {},
-      json_compiler: JsonCompiler {},
       include_deno_namespace,
-      lockfile,
     };
 
     Ok(ThreadSafeState(Arc::new(state)))
   }
 
-  pub fn fetch_compiled_module(
-    self: &Self,
-    module_specifier: &ModuleSpecifier,
-  ) -> impl Future<Item = CompiledModule, Error = ErrBox> {
-    let state1 = self.clone();
-    let state2 = self.clone();
-
-    self
-      .file_fetcher
-      .fetch_source_file_async(&module_specifier)
-      .and_then(move |out| match out.media_type {
-        msg::MediaType::Unknown => {
-          state1.js_compiler.compile_async(state1.clone(), &out)
-        }
-        msg::MediaType::Json => {
-          state1.json_compiler.compile_async(state1.clone(), &out)
-        }
-        msg::MediaType::TypeScript
-        | msg::MediaType::TSX
-        | msg::MediaType::JSX => {
-          state1.ts_compiler.compile_async(state1.clone(), &out)
-        }
-        msg::MediaType::JavaScript => {
-          if state1.ts_compiler.compile_js {
-            state1.ts_compiler.compile_async(state1.clone(), &out)
-          } else {
-            state1.js_compiler.compile_async(state1.clone(), &out)
-          }
-        }
-      })
-      .and_then(move |compiled_module| {
-        if let Some(ref lockfile) = state2.lockfile {
-          let mut g = lockfile.lock().unwrap();
-          if state2.flags.lock_write {
-            g.insert(&compiled_module);
-          } else if !g.check(&compiled_module)? {
-            eprintln!(
-              "Subresource integrety check failed --lock={}\n{}",
-              g.filename, compiled_module.name
-            );
-            std::process::exit(10);
-          }
-        }
-        Ok(compiled_module)
-      })
-  }
-
-  /// Read main module from argv
-  pub fn main_module(&self) -> Option<ModuleSpecifier> {
-    match &self.main_module {
-      Some(module_specifier) => Some(module_specifier.clone()),
-      None => None,
-    }
-  }
-
   #[inline]
   pub fn check_read(&self, filename: &str) -> Result<(), ErrBox> {
     self.permissions.check_read(filename)
@@ -403,10 +287,17 @@ impl ThreadSafeState {
 
   #[cfg(test)]
   pub fn mock(argv: Vec<String>) -> ThreadSafeState {
+    let module_specifier = if argv.is_empty() {
+      None
+    } else {
+      let module_specifier = ModuleSpecifier::resolve_url_or_path(&argv[0])
+        .expect("Invalid entry module");
+      Some(module_specifier)
+    };
+
     ThreadSafeState::new(
-      flags::DenoFlags::default(),
-      argv,
-      Progress::new(),
+      ThreadSafeGlobalState::mock(argv),
+      module_specifier,
       true,
     )
     .unwrap()
@@ -445,16 +336,3 @@ fn thread_safe() {
     String::from("hello.js"),
   ]));
 }
-
-#[test]
-fn import_map_given_for_repl() {
-  let _result = ThreadSafeState::new(
-    flags::DenoFlags {
-      import_map_path: Some("import_map.json".to_string()),
-      ..flags::DenoFlags::default()
-    },
-    vec![String::from("./deno")],
-    Progress::new(),
-    true,
-  );
-}
diff --git a/cli/worker.rs b/cli/worker.rs
index 4bb68fb95..90fb95af7 100644
--- a/cli/worker.rs
+++ b/cli/worker.rs
@@ -1,33 +1,57 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+use crate::deno_error::bad_resource;
 use crate::fmt_errors::JSError;
 use crate::ops;
+use crate::resources;
+use crate::resources::CoreResource;
+use crate::resources::ResourceId;
 use crate::state::ThreadSafeState;
 use deno;
+use deno::Buf;
 use deno::ErrBox;
 use deno::ModuleSpecifier;
 use deno::RecursiveLoad;
 use deno::StartupData;
 use futures::Async;
 use futures::Future;
+use futures::Poll;
+use futures::Sink;
+use futures::Stream;
 use std::env;
 use std::sync::Arc;
 use std::sync::Mutex;
+use tokio::sync::mpsc;
 use url::Url;
 
+/// Wraps mpsc channels into a generic resource so they can be referenced
+/// from ops and used to facilitate parent-child communication
+/// for workers.
+pub struct WorkerChannels {
+  pub sender: mpsc::Sender<Buf>,
+  pub receiver: mpsc::Receiver<Buf>,
+}
+
+impl CoreResource for WorkerChannels {
+  fn inspect_repr(&self) -> &str {
+    "worker"
+  }
+}
+
 /// Wraps deno::Isolate to provide source maps, ops for the CLI, and
-/// high-level module loading
+/// high-level module loading.
 #[derive(Clone)]
 pub struct Worker {
+  pub name: String,
   isolate: Arc<Mutex<deno::Isolate>>,
   pub state: ThreadSafeState,
 }
 
 impl Worker {
   pub fn new(
-    _name: String,
+    name: String,
     startup_data: StartupData,
     state: ThreadSafeState,
-  ) -> Worker {
+  ) -> Self {
     let isolate = Arc::new(Mutex::new(deno::Isolate::new(startup_data, false)));
     {
       let mut i = isolate.lock().unwrap();
@@ -61,12 +85,16 @@ impl Worker {
         Box::new(load_stream)
       });
 
-      let state_ = state.clone();
+      let global_state_ = state.global_state.clone();
       i.set_js_error_create(move |v8_exception| {
-        JSError::from_v8_exception(v8_exception, &state_.ts_compiler)
+        JSError::from_v8_exception(v8_exception, &global_state_.ts_compiler)
       })
     }
-    Self { isolate, state }
+    Self {
+      name,
+      isolate,
+      state,
+    }
   }
 
   /// Same as execute2() but the filename defaults to "$CWD/__anonymous__".
@@ -106,7 +134,7 @@ impl Worker {
     )
     .get_future(isolate);
     recursive_load.and_then(move |id| -> Result<(), ErrBox> {
-      worker.state.progress.done();
+      worker.state.global_state.progress.done();
       if is_prefetch {
         Ok(())
       } else {
@@ -115,6 +143,37 @@ impl Worker {
       }
     })
   }
+
+  /// Post message to worker as a host or privileged overlord
+  pub fn post_message(self: &Self, buf: Buf) -> Result<Async<()>, ErrBox> {
+    Worker::post_message_to_resource(self.state.rid, buf)
+  }
+
+  pub fn post_message_to_resource(
+    rid: resources::ResourceId,
+    buf: Buf,
+  ) -> Result<Async<()>, ErrBox> {
+    debug!("post message to resource {}", rid);
+    let mut table = resources::lock_resource_table();
+    let worker = table
+      .get_mut::<WorkerChannels>(rid)
+      .ok_or_else(bad_resource)?;
+    let sender = &mut worker.sender;
+    sender
+      .send(buf)
+      .poll()
+      .map(|_| Async::Ready(()))
+      .map_err(ErrBox::from)
+  }
+
+  pub fn get_message(self: &Self) -> WorkerReceiver {
+    Worker::get_message_from_resource(self.state.rid)
+  }
+
+  pub fn get_message_from_resource(rid: ResourceId) -> WorkerReceiver {
+    debug!("get message from resource {}", rid);
+    WorkerReceiver { rid }
+  }
 }
 
 impl Future for Worker {
@@ -127,16 +186,39 @@ impl Future for Worker {
   }
 }
 
+/// This structure wraps worker's resource id to implement future
+/// that will return message received from worker or None
+/// if worker's channel has been closed.
+pub struct WorkerReceiver {
+  rid: ResourceId,
+}
+
+impl Future for WorkerReceiver {
+  type Item = Option<Buf>;
+  type Error = ErrBox;
+
+  fn poll(&mut self) -> Poll<Option<Buf>, ErrBox> {
+    let mut table = resources::lock_resource_table();
+    let worker = table
+      .get_mut::<WorkerChannels>(self.rid)
+      .ok_or_else(bad_resource)?;
+    let receiver = &mut worker.receiver;
+    receiver.poll().map_err(ErrBox::from)
+  }
+}
+
 #[cfg(test)]
 mod tests {
   use super::*;
   use crate::flags;
+  use crate::flags::DenoFlags;
+  use crate::global_state::ThreadSafeGlobalState;
   use crate::progress::Progress;
-  use crate::resources;
   use crate::startup_data;
   use crate::state::ThreadSafeState;
   use crate::tokio_util;
   use futures::future::lazy;
+  use futures::IntoFuture;
   use std::sync::atomic::Ordering;
 
   #[test]
@@ -149,13 +231,15 @@ mod tests {
     let module_specifier =
       ModuleSpecifier::resolve_url_or_path(&p.to_string_lossy()).unwrap();
     let argv = vec![String::from("./deno"), module_specifier.to_string()];
-    let state = ThreadSafeState::new(
+    let global_state = ThreadSafeGlobalState::new(
       flags::DenoFlags::default(),
       argv,
       Progress::new(),
-      true,
     )
     .unwrap();
+    let state =
+      ThreadSafeState::new(global_state, Some(module_specifier.clone()), true)
+        .unwrap();
     let state_ = state.clone();
     tokio_util::run(lazy(move || {
       let mut worker =
@@ -186,13 +270,12 @@ mod tests {
     let module_specifier =
       ModuleSpecifier::resolve_url_or_path(&p.to_string_lossy()).unwrap();
     let argv = vec![String::from("deno"), module_specifier.to_string()];
-    let state = ThreadSafeState::new(
-      flags::DenoFlags::default(),
-      argv,
-      Progress::new(),
-      true,
-    )
-    .unwrap();
+    let global_state =
+      ThreadSafeGlobalState::new(DenoFlags::default(), argv, Progress::new())
+        .unwrap();
+    let state =
+      ThreadSafeState::new(global_state, Some(module_specifier.clone()), true)
+        .unwrap();
     let state_ = state.clone();
     tokio_util::run(lazy(move || {
       let mut worker =
@@ -227,8 +310,15 @@ mod tests {
     let argv = vec![String::from("deno"), module_specifier.to_string()];
     let mut flags = flags::DenoFlags::default();
     flags.reload = true;
-    let state =
-      ThreadSafeState::new(flags, argv, Progress::new(), true).unwrap();
+    let global_state =
+      ThreadSafeGlobalState::new(flags, argv, Progress::new()).unwrap();
+    let state = ThreadSafeState::new(
+      global_state.clone(),
+      Some(module_specifier.clone()),
+      true,
+    )
+    .unwrap();
+    let global_state_ = global_state.clone();
     let state_ = state.clone();
     tokio_util::run(lazy(move || {
       let mut worker = Worker::new(
@@ -247,10 +337,12 @@ mod tests {
         })
     }));
 
-    let metrics = &state_.metrics;
-    assert_eq!(metrics.resolve_count.load(Ordering::SeqCst), 3);
+    assert_eq!(state_.metrics.resolve_count.load(Ordering::SeqCst), 3);
     // Check that we've only invoked the compiler once.
-    assert_eq!(metrics.compiler_starts.load(Ordering::SeqCst), 1);
+    assert_eq!(
+      global_state_.metrics.compiler_starts.load(Ordering::SeqCst),
+      1
+    );
     drop(http_server_guard);
   }
 
@@ -285,8 +377,9 @@ mod tests {
         "#;
       worker.execute(source).unwrap();
 
-      let resource = worker.state.resource.clone();
-      let resource_ = resource.clone();
+      let worker_ = worker.clone();
+      let rid = worker.state.rid;
+      let resource_ = resources::Resource { rid };
 
       tokio::spawn(lazy(move || {
         worker.then(move |r| -> Result<(), ()> {
@@ -298,14 +391,10 @@ mod tests {
 
       let msg = json!("hi").to_string().into_boxed_str().into_boxed_bytes();
 
-      let r = resources::post_message_to_worker(resource.rid, msg)
-        .expect("Bad resource")
-        .wait();
+      let r = worker_.post_message(msg).into_future().wait();
       assert!(r.is_ok());
 
-      let maybe_msg = resources::get_message_from_worker(resource.rid)
-        .wait()
-        .unwrap();
+      let maybe_msg = worker_.get_message().wait().unwrap();
       assert!(maybe_msg.is_some());
       // Check if message received is [1, 2, 3] in json
       assert_eq!(*maybe_msg.unwrap(), *b"[1,2,3]");
@@ -314,9 +403,7 @@ mod tests {
         .to_string()
         .into_boxed_str()
         .into_boxed_bytes();
-      let r = resources::post_message_to_worker(resource.rid, msg)
-        .expect("Bad resource")
-        .wait();
+      let r = worker_.post_message(msg).into_future().wait();
       assert!(r.is_ok());
     })
   }
@@ -329,8 +416,9 @@ mod tests {
         .execute("onmessage = () => { delete window.onmessage; }")
         .unwrap();
 
-      let resource = worker.state.resource.clone();
-      let rid = resource.rid;
+      let rid = worker.state.rid;
+      let resource = resources::Resource { rid };
+      let worker_ = worker.clone();
 
       let worker_future = worker
         .then(move |r| -> Result<(), ()> {
@@ -345,9 +433,7 @@ mod tests {
       tokio::spawn(lazy(move || worker_future_.then(|_| Ok(()))));
 
       let msg = json!("hi").to_string().into_boxed_str().into_boxed_bytes();
-      let r = resources::post_message_to_worker(rid, msg)
-        .expect("Bad resource")
-        .wait();
+      let r = worker_.post_message(msg).into_future().wait();
       assert!(r.is_ok());
       debug!("rid {:?}", rid);