Remove global Cache (#448)

* Update to use Rust 2018.

* Update examples and use Rust 2018.

* Pass cache via `Context` around instead of being global.

* Remove `lazy_static` from `cache`-feature.

* Update examples to use `Context`'s cache.

* Replace cache's update-timeout-setting with `update_cache_timeout`.

* Update documentation to stop using global cache.

* Move `HttpAndCache` to `lib.rs`.

* Add `__nonexhaustive`-field to `CacheAndHttp`.

* Add `__nonexhaustive` in `CacheAndHttp`-initialisers.

* Avoid `__nonexhaustive`-usage in doctest.

* Remove unnecessary comma in `cfg`-attribute.

3 files changed, 19 insertions, 1 deletions

diff --git a/src/client/bridge/gateway/shard_manager.rs b/src/client/bridge/gateway/shard_manager.rs
index 45926ef..579b003 100644
--- a/src/client/bridge/gateway/shard_manager.rs
+++ b/src/client/bridge/gateway/shard_manager.rs
@@ -1,5 +1,6 @@
 use crate::gateway::InterMessage;
 use crate::internal::prelude::*;
+use crate::CacheAndHttp;
 use parking_lot::Mutex;
 use std::{
     collections::{HashMap, VecDeque},
@@ -50,14 +51,17 @@ use crate::client::bridge::voice::ClientVoiceManager;
 /// # use serenity::client::bridge::voice::ClientVoiceManager;
 /// # #[cfg(feature = "voice")]
 /// # use serenity::model::id::UserId;
+/// # #[cfg(feature = "cache")]
+/// # use serenity::cache::Cache;
 /// #
 /// # #[cfg(feature = "framework")]
 /// # fn try_main() -> Result<(), Box<Error>> {
 /// #
-/// use parking_lot::Mutex;
+/// use parking_lot::{Mutex, RwLock};
 /// use serenity::client::bridge::gateway::{ShardManager, ShardManagerOptions};
 /// use serenity::client::EventHandler;
 /// use serenity::http;
+/// use serenity::CacheAndHttp;
 /// use std::sync::Arc;
 /// use std::env;
 /// use threadpool::ThreadPool;
@@ -76,6 +80,7 @@ use crate::client::bridge::voice::ClientVoiceManager;
 /// let event_handler = Arc::new(Handler);
 /// let framework = Arc::new(Mutex::new(None));
 /// let threadpool = ThreadPool::with_name("my threadpool".to_owned(), 5);
+/// let cache_and_http = Arc::new(CacheAndHttp::default());
 ///
 /// ShardManager::new(ShardManagerOptions {
 ///     data: &data,
@@ -92,6 +97,7 @@ use crate::client::bridge::voice::ClientVoiceManager;
 ///     # #[cfg(feature = "voice")]
 ///     # voice_manager: &Arc::new(Mutex::new(ClientVoiceManager::new(0, UserId(0)))),
 ///     ws_url: &gateway_url,
+///     cache_and_http: &cache_and_http,
 /// });
 /// #     Ok(())
 /// # }
@@ -151,6 +157,7 @@ impl ShardManager {
             #[cfg(feature = "voice")]
             voice_manager: Arc::clone(opt.voice_manager),
             ws_url: Arc::clone(opt.ws_url),
+            cache_and_http: Arc::clone(&opt.cache_and_http),
         };
 
         thread::spawn(move || {
@@ -362,4 +369,5 @@ pub struct ShardManagerOptions<'a, H: EventHandler + Send + Sync + 'static> {
     #[cfg(feature = "voice")]
     pub voice_manager: &'a Arc<Mutex<ClientVoiceManager>>,
     pub ws_url: &'a Arc<Mutex<String>>,
+    pub cache_and_http: &'a Arc<CacheAndHttp>,
 }
diff --git a/src/client/bridge/gateway/shard_queuer.rs b/src/client/bridge/gateway/shard_queuer.rs
index 5152249..12df4c8 100644
--- a/src/client/bridge/gateway/shard_queuer.rs
+++ b/src/client/bridge/gateway/shard_queuer.rs
@@ -1,5 +1,6 @@
 use crate::gateway::Shard;
 use crate::internal::prelude::*;
+use crate::CacheAndHttp;
 use parking_lot::Mutex;
 use std::{
     collections::{HashMap, VecDeque},
@@ -85,6 +86,7 @@ pub struct ShardQueuer<H: EventHandler + Send + Sync + 'static> {
     pub voice_manager: Arc<Mutex<ClientVoiceManager>>,
     /// A copy of the URI to use to connect to the gateway.
     pub ws_url: Arc<Mutex<String>>,
+    pub cache_and_http: Arc<CacheAndHttp>,
 }
 
 impl<H: EventHandler + Send + Sync + 'static> ShardQueuer<H> {
@@ -188,6 +190,7 @@ impl<H: EventHandler + Send + Sync + 'static> ShardQueuer<H> {
             #[cfg(feature = "voice")]
             voice_manager: Arc::clone(&self.voice_manager),
             shard,
+            cache_and_http: Arc::clone(&self.cache_and_http),
         });
 
         let runner_info = ShardRunnerInfo {
diff --git a/src/client/bridge/gateway/shard_runner.rs b/src/client/bridge/gateway/shard_runner.rs
index 5e2a1ff..fe71462 100644
--- a/src/client/bridge/gateway/shard_runner.rs
+++ b/src/client/bridge/gateway/shard_runner.rs
@@ -2,6 +2,7 @@ use crate::gateway::{InterMessage, ReconnectType, Shard, ShardAction};
 use crate::internal::prelude::*;
 use crate::internal::ws_impl::{ReceiverExt, SenderExt};
 use crate::model::event::{Event, GatewayEvent};
+use crate::CacheAndHttp;
 use parking_lot::Mutex;
 use serde::Deserialize;
 use std::{
@@ -32,6 +33,7 @@ use crate::framework::Framework;
 #[cfg(feature = "voice")]
 use super::super::voice::ClientVoiceManager;
 
+
 /// A runner for managing a [`Shard`] and its respective WebSocket client.
 ///
 /// [`Shard`]: ../../../gateway/struct.Shard.html
@@ -49,6 +51,7 @@ pub struct ShardRunner<H: EventHandler + Send + Sync + 'static> {
     threadpool: ThreadPool,
     #[cfg(feature = "voice")]
     voice_manager: Arc<Mutex<ClientVoiceManager>>,
+    cache_and_http: Arc<CacheAndHttp>,
 }
 
 impl<H: EventHandler + Send + Sync + 'static> ShardRunner<H> {
@@ -68,6 +71,7 @@ impl<H: EventHandler + Send + Sync + 'static> ShardRunner<H> {
             threadpool: opt.threadpool,
             #[cfg(feature = "voice")]
             voice_manager: opt.voice_manager,
+            cache_and_http: opt.cache_and_http,
         }
     }
 
@@ -212,6 +216,7 @@ impl<H: EventHandler + Send + Sync + 'static> ShardRunner<H> {
             &self.runner_tx,
             &self.threadpool,
             self.shard.shard_info()[0],
+            Arc::clone(&self.cache_and_http),
         );
     }
 
@@ -493,4 +498,6 @@ pub struct ShardRunnerOptions<H: EventHandler + Send + Sync + 'static> {
     pub threadpool: ThreadPool,
     #[cfg(feature = "voice")]
     pub voice_manager: Arc<Mutex<ClientVoiceManager>>,
+    #[cfg(feature = "cache")]
+    pub cache_and_http: Arc<CacheAndHttp>,
 }