feat(plugin): add manifest to allow for plugin configuration (#660)

* feat(plugins-manifest): Add a plugins manifest to allow for more configuration of plugins

* refactor(plugins-manifest): Better storage of plugin metadata in wasm_vm

* fix(plugins-manifest): Inherit permissions from run configuration

* refactor(plugins-manifest): Rename things for more clarity

- The Plugins/Plugin structs had "Config" appended to them to clarify
  that they're metadata about plugins, and not the plugins themselves.

- The PluginType::OncePerPane variant was renamed to be just
  PluginType::Pane, and the documentation clarified to explain what it
  is.

- The "service" nomenclature was completely removed in favor of
  "headless".

* refactor(plugins-manifest): Move security warning into start plugin

* refactor(plugins-manifest): Remove hack in favor of standard method

* refactor(plugins-manifest): Change display of plugin location

The only time that a plugin location is displayed in Zellij is the
border of the pane. Having `zellij:strider` display instead of just
`strider` was a little annoying, so we're stripping out the scheme
information from a locations display.

* refactor(plugins-manifest): Add a little more documentation

* fix(plugins-manifest): Formatting

Co-authored-by: Jesse Tuchsen <not@disclosing>

25 files changed, 832 insertions, 185 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 66a0b3cbc..bf4ae0fd9 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -749,6 +749,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
 [[package]]
+name = "form_urlencoded"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5fc25a87fa4fd2094bffb06925852034d90a17f0d1e05197d4956d3555752191"
+dependencies = [
+ "matches",
+ "percent-encoding",
+]
+
+[[package]]
 name = "fuchsia-cprng"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -971,6 +981,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9e0384b61958566e926dc50660321d12159025e767c18e043daf26b70104c39"
 
 [[package]]
+name = "idna"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "418a0a6fab821475f634efe3ccc45c013f742efe03d853e8d3355d5cb850ecf8"
+dependencies = [
+ "matches",
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
+[[package]]
 name = "indexmap"
 version = "1.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1207,6 +1228,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "matches"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3e378b66a060d48947b590737b30a1be76706c8dd7b8ba0f2fe3989c68a853f"
+
+[[package]]
 name = "memchr"
 version = "2.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -1433,6 +1460,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "percent-encoding"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
+
+[[package]]
 name = "pin-project-lite"
 version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2108,6 +2141,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "tinyvec"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "848a1e1181b9f6753b5e96a092749e29b11d19ede67dfbbd6c7dc7e0f49b5338"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
+
+[[package]]
 name = "tracing"
 version = "0.1.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2180,6 +2228,21 @@ dependencies = [
 ]
 
 [[package]]
+name = "unicode-bidi"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "246f4c42e67e7a4e3c6106ff716a5d067d4132a642840b242e357e468a2a0085"
+
+[[package]]
+name = "unicode-normalization"
+version = "0.1.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d54590932941a9e9266f0832deed84ebe1bf2e4c9e4a3554d393d18f5e854bf9"
+dependencies = [
+ "tinyvec",
+]
+
+[[package]]
 name = "unicode-segmentation"
 version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2207,6 +2270,19 @@ dependencies = [
 ]
 
 [[package]]
+name = "url"
+version = "2.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a507c383b2d33b5fc35d1861e77e6b383d158b2da5e14fe51b83dfedf6fd578c"
+dependencies = [
+ "form_urlencoded",
+ "idna",
+ "matches",
+ "percent-encoding",
+ "serde",
+]
+
+[[package]]
 name = "utf8parse"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -2680,6 +2756,7 @@ dependencies = [
  "serde_json",
  "typetag",
  "unicode-width",
+ "url",
  "wasmer",
  "wasmer-wasi",
  "zellij-utils",
@@ -2720,6 +2797,7 @@ dependencies = [
  "nix",
  "once_cell",
  "serde",
+ "serde_json",
  "serde_yaml",
  "signal-hook 0.3.9",
  "strip-ansi-escapes",
@@ -2728,6 +2806,7 @@ dependencies = [
  "tempfile",
  "termion",
  "unicode-width",
+ "url",
  "vte 0.10.1",
  "zellij-tile",
 ]
diff --git a/zellij-client/src/lib.rs b/zellij-client/src/lib.rs
index bd2c63768..b4d63d274 100644
--- a/zellij-client/src/lib.rs
+++ b/zellij-client/src/lib.rs
@@ -138,6 +138,7 @@ pub fn start_client(
                 Box::new(opts),
                 Box::new(config_options.clone()),
                 layout.unwrap(),
+                Some(config.plugins.clone()),
             )
         }
     };
diff --git a/zellij-server/Cargo.toml b/zellij-server/Cargo.toml
index bc0abe310..c9f98ecf1 100644
--- a/zellij-server/Cargo.toml
+++ b/zellij-server/Cargo.toml
@@ -16,6 +16,7 @@ byteorder = "1.4.3"
 daemonize = "0.4.1"
 serde_json = "1.0"
 unicode-width = "0.1.8"
+url = "2.2.2"
 wasmer = "1.0.0"
 wasmer-wasi = "1.0.0"
 cassowary = "0.3.0"
diff --git a/zellij-server/src/lib.rs b/zellij-server/src/lib.rs
index 419aae4f6..36569522e 100644
--- a/zellij-server/src/lib.rs
+++ b/zellij-server/src/lib.rs
@@ -38,6 +38,7 @@ use zellij_utils::{
         get_mode_info,
         layout::LayoutFromYaml,
         options::Options,
+        plugins::PluginsConfig,
     },
     ipc::{ClientAttributes, ClientToServerMsg, ExitReason, ServerToClientMsg},
     setup::get_default_data_dir,
@@ -46,7 +47,13 @@ use zellij_utils::{
 /// Instructions related to server-side application
 #[derive(Debug, Clone)]
 pub(crate) enum ServerInstruction {
-    NewClient(ClientAttributes, Box<CliArgs>, Box<Options>, LayoutFromYaml),
+    NewClient(
+        ClientAttributes,
+        Box<CliArgs>,
+        Box<Options>,
+        LayoutFromYaml,
+        Option<PluginsConfig>,
+    ),
     Render(Option<String>),
     UnblockInputThread,
     ClientExit,
@@ -58,8 +65,8 @@ pub(crate) enum ServerInstruction {
 impl From<ClientToServerMsg> for ServerInstruction {
     fn from(instruction: ClientToServerMsg) -> Self {
         match instruction {
-            ClientToServerMsg::NewClient(attrs, opts, options, layout) => {
-                ServerInstruction::NewClient(attrs, opts, options, layout)
+            ClientToServerMsg::NewClient(attrs, opts, options, layout, plugins) => {
+                ServerInstruction::NewClient(attrs, opts, options, layout, plugins)
             }
             ClientToServerMsg::AttachClient(attrs, force, options) => {
                 ServerInstruction::AttachClient(attrs, force, options)
@@ -193,15 +200,24 @@ pub fn start_server(os_input: Box<dyn ServerOsApi>, socket_path: PathBuf) {
         let (instruction, mut err_ctx) = server_receiver.recv().unwrap();
         err_ctx.add_call(ContextType::IPCServer((&instruction).into()));
         match instruction {
-            ServerInstruction::NewClient(client_attributes, opts, config_options, layout) => {
+            ServerInstruction::NewClient(
+                client_attributes,
+                opts,
+                config_options,
+                layout,
+                plugins,
+            ) => {
                 let session = init_session(
                     os_input.clone(),
-                    opts,
-                    config_options.clone(),
                     to_server.clone(),
                     client_attributes,
                     session_state.clone(),
-                    layout.clone(),
+                    SessionOptions {
+                        opts,
+                        layout: layout.clone(),
+                        plugins,
+                        config_options: config_options.clone(),
+                    },
                 );
                 *session_data.write().unwrap() = Some(session);
                 *session_state.write().unwrap() = SessionState::Attached;
@@ -302,15 +318,26 @@ pub fn start_server(os_input: Box<dyn ServerOsApi>, socket_path: PathBuf) {
     drop(std::fs::remove_file(&socket_path));
 }
 
+pub struct SessionOptions {
+    pub opts: Box<CliArgs>,
+    pub config_options: Box<Options>,
+    pub layout: LayoutFromYaml,
+    pub plugins: Option<PluginsConfig>,
+}
+
 fn init_session(
     os_input: Box<dyn ServerOsApi>,
-    opts: Box<CliArgs>,
-    config_options: Box<Options>,
     to_server: SenderWithContext<ServerInstruction>,
     client_attributes: ClientAttributes,
     session_state: Arc<RwLock<SessionState>>,
-    layout: LayoutFromYaml,
+    options: SessionOptions,
 ) -> SessionMetaData {
+    let SessionOptions {
+        opts,
+        config_options,
+        layout,
+        plugins,
+    } = options;
     let (to_screen, screen_receiver): ChannelWithContext<ScreenInstruction> = channels::unbounded();
     let to_screen = SenderWithContext::new(to_screen);
 
@@ -394,7 +421,7 @@ fn init_session(
             );
             let store = Store::default();
 
-            move || wasm_thread_main(plugin_bus, store, data_dir)
+            move || wasm_thread_main(plugin_bus, store, data_dir, plugins.unwrap_or_default())
         })
         .unwrap();
     SessionMetaData {
diff --git a/zellij-server/src/pty.rs b/zellij-server/src/pty.rs
index e37e60621..761b1702f 100644
--- a/zellij-server/src/pty.rs
+++ b/zellij-server/src/pty.rs
@@ -65,6 +65,8 @@ pub(crate) struct Pty {
     task_handles: HashMap<RawFd, JoinHandle<()>>,
 }
 
+use std::convert::TryFrom;
+
 pub(crate) fn pty_thread_main(mut pty: Pty, layout: LayoutFromYaml) {
     loop {
         let (event, mut err_ctx) = pty.bus.recv().expect("failed to receive event on channel");
@@ -104,7 +106,10 @@ pub(crate) fn pty_thread_main(mut pty: Pty, layout: LayoutFromYaml) {
                 });
 
                 let merged_layout = layout.template.clone().insert_tab_layout(tab_layout);
-                pty.spawn_terminals_for_layout(merged_layout.into(), terminal_action.clone());
+                let layout: Layout =
+                    Layout::try_from(merged_layout).unwrap_or_else(|err| panic!("{}", err));
+
+                pty.spawn_terminals_for_layout(layout, terminal_action.clone());
 
                 if let Some(tab_name) = tab_name {
                     // clear current name at first
diff --git a/zellij-server/src/tab.rs b/zellij-server/src/tab.rs
index 62e0a2cb5..fa62cfce9 100644
--- a/zellij-server/src/tab.rs
+++ b/zellij-server/src/tab.rs
@@ -322,23 +322,18 @@ impl Tab {
 
         for (layout, position_and_size) in positions_and_size {
             // A plugin pane
-            if let Some(Run::Plugin(Some(plugin))) = &layout.run {
+            if let Some(Run::Plugin(run)) = layout.run.clone() {
                 let (pid_tx, pid_rx) = channel();
+                let pane_title = run.location.to_string();
                 self.senders
-                    .send_to_plugin(PluginInstruction::Load(
-                        pid_tx,
-                        plugin.path.clone(),
-                        tab_index,
-                        plugin._allow_exec_host_cmd,
-                    ))
+                    .send_to_plugin(PluginInstruction::Load(pid_tx, run, tab_index))
                     .unwrap();
                 let pid = pid_rx.recv().unwrap();
-                let title = String::from(plugin.path.as_path().as_os_str().to_string_lossy());
                 let mut new_plugin = PluginPane::new(
                     pid,
                     *position_and_size,
                     self.senders.to_plugin.as_ref().unwrap().clone(),
-                    title,
+                    pane_title,
                 );
                 new_plugin.set_borderless(layout.borderless);
                 self.panes.insert(PaneId::Plugin(pid), Box::new(new_plugin));
diff --git a/zellij-server/src/unit/screen_tests.rs b/zellij-server/src/unit/screen_tests.rs
index aeea671ba..e1df2c64c 100644
--- a/zellij-server/src/unit/screen_tests.rs
+++ b/zellij-server/src/unit/screen_tests.rs
@@ -5,6 +5,7 @@ use crate::{
     thread_bus::Bus,
     SessionState,
 };
+use std::convert::TryInto;
 use std::path::PathBuf;
 use std::sync::{Arc, RwLock};
 use zellij_utils::input::command::TerminalAction;
@@ -101,7 +102,7 @@ fn create_new_screen(size: Size) -> Screen {
 }
 
 fn new_tab(screen: &mut Screen, pid: i32) {
-    screen.apply_layout(LayoutTemplate::default().into(), vec![pid]);
+    screen.apply_layout(LayoutTemplate::default().try_into().unwrap(), vec![pid]);
 }
 
 #[test]
diff --git a/zellij-server/src/unit/tab_tests.rs b/zellij-server/src/unit/tab_tests.rs
index de5c10670..7f0fa71f8 100644
--- a/zellij-server/src/unit/tab_tests.rs
+++ b/zellij-server/src/unit/tab_tests.rs
@@ -6,6 +6,7 @@ use crate::{
     thread_bus::ThreadSenders,
     SessionState,
 };
+use std::convert::TryInto;
 use std::path::PathBuf;
 use std::sync::{Arc, RwLock};
 use zellij_utils::input::layout::LayoutTemplate;
@@ -101,7 +102,11 @@ fn create_new_tab(size: Size) -> Tab {
         session_state,
         true, // draw pane frames
     );
-    tab.apply_layout(LayoutTemplate::default().into(), vec![1], index);
+    tab.apply_layout(
+        LayoutTemplate::default().try_into().unwrap(),
+        vec![1],
+        index,
+    );
     tab
 }
 
diff --git a/zellij-server/src/wasm_vm.rs b/zellij-server/src/wasm_vm.rs
index 40967c5a3..1d67e8477 100644
--- a/zellij-server/src/wasm_vm.rs
+++ b/zellij-server/src/wasm_vm.rs
@@ -1,7 +1,7 @@
-use log::{info, warn};
+use log::{debug, info, warn};
 use std::collections::{HashMap, HashSet};
 use std::fs;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::process;
 use std::str::FromStr;
 use std::sync::{mpsc::Sender, Arc, Mutex};
@@ -9,6 +9,7 @@ use std::thread;
 use std::time::{Duration, Instant};
 
 use serde::{de::DeserializeOwned, Serialize};
+use url::Url;
 use wasmer::{
     imports, ChainableNamedResolver, Function, ImportObject, Instance, Module, Store, Value,
     WasmerEnv,
@@ -24,12 +25,17 @@ use crate::{
     thread_bus::{Bus, ThreadSenders},
 };
 use zellij_utils::errors::{ContextType, PluginContext};
-use zellij_utils::{input::command::TerminalAction, serde, zellij_tile};
+use zellij_utils::{
+    input::command::TerminalAction,
+    input::layout::RunPlugin,
+    input::plugins::{PluginConfig, PluginType, PluginsConfig},
+    serde, zellij_tile,
+};
 
 #[derive(Clone, Debug)]
 pub(crate) enum PluginInstruction {
-    Load(Sender<u32>, PathBuf, usize, bool), // tx_pid, path_of_plugin , tab_index, allow_exec_host_cmd
-    Update(Option<u32>, Event),              // Focused plugin / broadcast, event data
+    Load(Sender<u32>, RunPlugin, usize), // tx_pid, plugin metadata, tab_index
+    Update(Option<u32>, Event),          // Focused plugin / broadcast, event data
     Render(Sender<String>, u32, usize, usize), // String buffer, plugin id, rows, cols
     Unload(u32),
     Exit,
@@ -50,83 +56,62 @@ impl From<&PluginInstruction> for PluginContext {
 #[derive(WasmerEnv, Clone)]
 pub(crate) struct PluginEnv {
     pub plugin_id: u32,
-    pub tab_index: usize,
+    pub plugin: PluginConfig,
     pub senders: ThreadSenders,
     pub wasi_env: WasiEnv,
     pub subscriptions: Arc<Mutex<HashSet<EventType>>>,
-    // FIXME: Once permission system is ready, this could be removed
-    pub _allow_exec_host_cmd: bool,
     plugin_own_data_dir: PathBuf,
 }
 
 // Thread main --------------------------------------------------------------------------------------------------------
-pub(crate) fn wasm_thread_main(bus: Bus<PluginInstruction>, store: Store, data_dir: PathBuf) {
+pub(crate) fn wasm_thread_main(
+    bus: Bus<PluginInstruction>,
+    store: Store,
+    data_dir: PathBuf,
+    plugins: PluginsConfig,
+) {
     info!("Wasm main thread starts");
+
     let mut plugin_id = 0;
     let mut plugin_map = HashMap::new();
     let plugin_dir = data_dir.join("plugins/");
     let plugin_global_data_dir = plugin_dir.join("data");
     fs::create_dir_all(plugin_global_data_dir.as_path()).unwrap();
 
+    for plugin in plugins.iter() {
+        if let PluginType::Headless = plugin.run {
+            let (instance, plugin_env) = start_plugin(
+                plugin_id,
+                plugin,
+                0,
+                &bus,
+                &store,
+                &data_dir,
+                &plugin_global_data_dir,
+            );
+            plugin_map.insert(plugin_id, (instance, plugin_env));
+            plugin_id += 1;
+        }
+    }
+
     loop {
         let (event, mut err_ctx) = bus.recv().expect("failed to receive event on channel");
         err_ctx.add_call(ContextType::Plugin((&event).into()));
         match event {
-            PluginInstruction::Load(pid_tx, path, tab_index, _allow_exec_host_cmd) => {
-                let wasm_bytes = fs::read(&path)
-                    .or_else(|_| fs::read(&path.with_extension("wasm")))
-                    .or_else(|_| fs::read(&plugin_dir.join(&path).with_extension("wasm")))
-                    .unwrap_or_else(|_| panic!("cannot find plugin {}", &path.display()));
-
-                // FIXME: Cache this compiled module on disk. I could use `(de)serialize_to_file()` for that
-                let module = Module::new(&store, &wasm_bytes).unwrap();
-
-                let output = Pipe::new();
-                let input = Pipe::new();
-                let stderr = LoggingPipe::new(
-                    path.as_path().file_name().unwrap().to_str().unwrap(),
-                    plugin_id,
-                );
+            PluginInstruction::Load(pid_tx, run, tab_index) => {
+                let plugin = plugins
+                    .get(&run)
+                    .unwrap_or_else(|| panic!("Plugin {:?} could not be resolved", run));
 
-                let plugin_name = path.as_path().file_stem().unwrap();
-                let plugin_own_data_dir = plugin_global_data_dir.join(plugin_name);
-                fs::create_dir_all(&plugin_own_data_dir).unwrap();
-
-                let mut wasi_env = WasiState::new("Zellij")
-                    .env("CLICOLOR_FORCE", "1")
-                    .map_dir("/host", ".")
-                    .unwrap()
-                    .map_dir("/data", plugin_own_data_dir.as_path())
-                    .unwrap()
-                    .stdin(Box::new(input))
-                    .stdout(Box::new(output))
-                    .stderr(Box::new(stderr))
-                    .finalize()
-                    .unwrap();
-
-                let wasi = wasi_env.import_object(&module).unwrap();
-
-                if _allow_exec_host_cmd {
-                    info!("Plugin({:?}) is able to run any host command, this may lead to some security issues!", path);
-                }
-
-                let plugin_env = PluginEnv {
+                let (instance, plugin_env) = start_plugin(
                     plugin_id,
+                    &plugin,
                     tab_index,
-                    senders: bus.senders.clone(),
-                    wasi_env,
-                    subscriptions: Arc::new(Mutex::new(HashSet::new())),
-                    _allow_exec_host_cmd,
-                    plugin_own_data_dir,
-                };
-