Remove `use_connection` (#1859)

* feat: remove use_connection

* fix: clear old test

1 files changed, 17 insertions, 50 deletions

diff --git a/docs/docs/connections.md b/docs/docs/connections.md
index f58da10..4382cef 100644
--- a/docs/docs/connections.md
+++ b/docs/docs/connections.md
@@ -3,61 +3,20 @@ title: "RQ: Connections"
 layout: docs
 ---
 
-Although RQ features the `use_connection()` command for convenience, it
-is deprecated, since it pollutes the global namespace.  Instead, prefer explicit
-connection management using the `with Connection(...):` context manager, or
-pass in Redis connection references to queues directly.
+### The connection parameter
 
-
-## Single Redis connection (easy)
-
-<div class="warning">
-    <img style="float: right; margin-right: -60px; margin-top: -38px" src="/img/warning.png" />
-    <strong>Note:</strong>
-    <p>
-        The use of <code>use_connection</code> is deprecated.
-        Please don't use <code>use_connection</code> in your scripts.
-        Instead, use explicit connection management.
-    </p>
-</div>
-
-In development mode, to connect to a default, local Redis server:
-
-```python
-from rq import use_connection
-use_connection()
-```
-
-In production, to connect to a specific Redis server:
+Each RQ object (queues, workers, jobs) has a `connection` keyword
+argument that can be passed to the constructor - this is the recommended way of handling connections.
 
 ```python
 from redis import Redis
-from rq import use_connection
+from rq import Queue
 
-redis = Redis('my.host.org', 6789, password='secret')
-use_connection(redis)
+redis = Redis('localhost', 6789)
+q = Queue(connection=redis)
 ```
 
-Be aware of the fact that `use_connection` pollutes the global namespace.  It
-also implies that you can only ever use a single connection.
-
-
-## Multiple Redis connections
-
-However, the single connection pattern facilitates only those cases where you
-connect to a single Redis instance, and where you affect global context (by
-replacing the existing connection with the `use_connection()` call).  You can
-only use this pattern when you are in full control of your web stack.
-
-In any other situation, or when you want to use multiple connections, you
-should use `Connection` contexts or pass connections around explicitly.
-
-
-### Explicit connections (precise, but tedious)
-
-Each RQ object instance (queues, workers, jobs) has a `connection` keyword
-argument that can be passed to the constructor.  Using this, you don't need to
-use `use_connection()`.  Instead, you can create your queues like this:
+This pattern allows for different connections to be passed to different objects:
 
 ```python
 from rq import Queue
@@ -73,11 +32,19 @@ q2 = Queue('bar', connection=conn2)
 Every job that is enqueued on a queue will know what connection it belongs to.
 The same goes for the workers.
 
-This approach is very precise, but rather verbose, and therefore, tedious.
-
 
 ### Connection contexts (precise and concise)
 
+<div class="warning">
+    <img style="float: right; margin-right: -60px; margin-top: -38px" src="/img/warning.png" />
+    <strong>Note:</strong>
+    <p>
+        The use of <code>Connection</code> context manager is deprecated.
+        Please don't use <code>Connection</code> in your scripts.
+        Instead, use explicit connection management.
+    </p>
+</div>
+
 There is a better approach if you want to use multiple connections, though.
 Each RQ object instance, upon creation, will use the topmost Redis connection
 on the RQ connection stack, which is a mechanism to temporarily replace the