From fa09ebfd829c28c1f1a92ec9381709f6903c67b1 Mon Sep 17 00:00:00 2001
From: Moritz Hedtke <13287984+mohe2015@users.noreply.github.com>
Date: Mon, 27 Apr 2020 22:31:26 +0200
Subject: [PATCH] Add example of combining providers to README.md
---
README.md | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)
diff --git a/README.md b/README.md
index f31d1905..3d6b8cfe 100644
--- a/README.md
+++ b/README.md
@@ -137,6 +137,50 @@ Now you understand how types are defined on a shared document. Next you can jump
to the [demo repository](https://github.com/yjs/yjs-demos) or continue reading
the API docs.
+### Example: Using and combining providers
+
+The most common way to combine providers is probably to combine some network provider with the local indexeddb provider:
+```typescript
+import * as Y from 'yjs'
+import { WebrtcProvider } from 'y-webrtc'
+import { IndexeddbPersistence } from 'y-indexeddb'
+
+async function main() {
+ const ydoc = new Y.Doc()
+
+ // this allows you to instantly get the (cached) documents data
+ let idbP = new IndexeddbPersistence('count-demo', ydoc)
+ await idbP.whenSynced
+
+ // this will sync between clients in the background, may be replaced by any network provider
+ let webP = new WebrtcProvider('count-demo', ydoc)
+ webP.connect()
+
+ // array of numbers which produce a sum
+ const yarray = ydoc.getArray('count')
+
+ // add 1 to the sum
+ yarray.push([1])
+
+ // observe changes of the sum
+ yarray.observe(event => {
+ // this will print updates from the network
+ console.log("new sum: " + yarray.toArray().reduce((a,b)=>(a+b)))
+ })
+
+ // print initial number (the cached one plus one)
+ let sum = yarray.toArray().reduce((a,b)=>(a+b))
+ console.log(sum)
+}
+main()
+
+```
+Example output:
+```bash
+32 # stored sum from indexeddb (with 1 already added to it)
+new sum: 38 # delayed new sum fetched from network
+```
+
## API
```js