6 files changed, 106 insertions, 0 deletions
diff --git a/runtime/js/40_plugins.js b/runtime/js/40_plugins.js
new file mode 100644
index 000000000..0796fd5ce
--- /dev/null
+++ b/runtime/js/40_plugins.js
@@ -0,0 +1,16 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+"use strict";
+
+((window) => {
+  const core = window.Deno.core;
+
+  function openPlugin(filename) {
+    const rid = core.opSync("op_open_plugin", filename);
+    core.syncOpsCache();
+    return rid;
+  }
+
+  window.__bootstrap.plugins = {
+    openPlugin,
+  };
+})(this);
diff --git a/runtime/js/90_deno_ns.js b/runtime/js/90_deno_ns.js
index 89c9ef060..e4d0b00f2 100644
--- a/runtime/js/90_deno_ns.js
+++ b/runtime/js/90_deno_ns.js
@@ -109,6 +109,7 @@
     Signal: __bootstrap.signals.Signal,
     SignalStream: __bootstrap.signals.SignalStream,
     emit: __bootstrap.compilerApi.emit,
+    openPlugin: __bootstrap.plugins.openPlugin,
     kill: __bootstrap.process.kill,
     setRaw: __bootstrap.tty.setRaw,
     consoleSize: __bootstrap.tty.consoleSize,
diff --git a/runtime/ops/mod.rs b/runtime/ops/mod.rs
index 7b0832618..c94020780 100644
--- a/runtime/ops/mod.rs
+++ b/runtime/ops/mod.rs
@@ -5,6 +5,7 @@ pub mod fs_events;
 pub mod io;
 pub mod os;
 pub mod permissions;
+pub mod plugin;
 pub mod process;
 pub mod runtime;
 pub mod signal;
diff --git a/runtime/ops/plugin.rs b/runtime/ops/plugin.rs
new file mode 100644
index 000000000..cc3bf93d5
--- /dev/null
+++ b/runtime/ops/plugin.rs
@@ -0,0 +1,86 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+use crate::permissions::Permissions;
+use deno_core::error::AnyError;
+use deno_core::op_sync;
+use deno_core::Extension;
+use deno_core::OpState;
+use deno_core::Resource;
+use deno_core::ResourceId;
+use dlopen::symbor::Library;
+use log::debug;
+use std::borrow::Cow;
+use std::mem;
+use std::path::PathBuf;
+use std::rc::Rc;
+
+/// A default `init` function for plugins which mimics the way the internal
+/// extensions are initalized. Plugins currently do not support all extension
+/// features and are most likely not going to in the future. Currently only
+/// `init_state` and `init_ops` are supported while `init_middleware` and `init_js`
+/// are not. Currently the `PluginResource` does not support being closed due to
+/// certain risks in unloading the dynamic library without unloading dependent
+/// functions and resources.
+pub type InitFn = fn() -> Extension;
+
+pub fn init() -> Extension {
+  Extension::builder()
+    .ops(vec![("op_open_plugin", op_sync(op_open_plugin))])
+    .build()
+}
+
+pub fn op_open_plugin(
+  state: &mut OpState,
+  filename: String,
+  _: (),
+) -> Result<ResourceId, AnyError> {
+  let filename = PathBuf::from(&filename);
+
+  super::check_unstable(state, "Deno.openPlugin");
+  let permissions = state.borrow_mut::<Permissions>();
+  permissions.plugin.check()?;
+
+  debug!("Loading Plugin: {:#?}", filename);
+  let plugin_lib = Library::open(filename).map(Rc::new)?;
+  let plugin_resource = PluginResource::new(&plugin_lib);
+
+  // Forgets the plugin_lib value to prevent segfaults when the process exits
+  mem::forget(plugin_lib);
+
+  let init = *unsafe { plugin_resource.0.symbol::<InitFn>("init") }?;
+  let rid = state.resource_table.add(plugin_resource);
+  let mut extension = init();
+
+  if !extension.init_js().is_empty() {
+    panic!("Plugins do not support loading js");
+  }
+
+  if extension.init_middleware().is_some() {
+    panic!("Plugins do not support middleware");
+  }
+
+  extension.init_state(state)?;
+  let ops = extension.init_ops().unwrap_or_default();
+  for (name, opfn) in ops {
+    state.op_table.register_op(name, opfn);
+  }
+
+  Ok(rid)
+}
+
+struct PluginResource(Rc<Library>);
+
+impl Resource for PluginResource {
+  fn name(&self) -> Cow<str> {
+    "plugin".into()
+  }
+
+  fn close(self: Rc<Self>) {
+    unimplemented!();
+  }
+}
+
+impl PluginResource {
+  fn new(lib: &Rc<Library>) -> Self {
+    Self(lib.clone())
+  }
+}
diff --git a/runtime/web_worker.rs b/runtime/web_worker.rs
index 1fcd57dc2..57a8142be 100644
--- a/runtime/web_worker.rs
+++ b/runtime/web_worker.rs
@@ -335,6 +335,7 @@ impl WebWorker {
         deno_net::init::<Permissions>(options.unstable),
         ops::os::init(),
         ops::permissions::init(),
+        ops::plugin::init(),
         ops::process::init(),
         ops::signal::init(),
         ops::tty::init(),
diff --git a/runtime/worker.rs b/runtime/worker.rs
index 543eae6f6..91810449d 100644
--- a/runtime/worker.rs
+++ b/runtime/worker.rs
@@ -126,6 +126,7 @@ impl MainWorker {
       deno_net::init::<Permissions>(options.unstable),
       ops::os::init(),
       ops::permissions::init(),
+      ops::plugin::init(),
       ops::process::init(),
       ops::signal::init(),
       ops::tty::init(),