refactor: switch to async (#15)

BREAKING CHANGE: Switch to using async/await

Author: vasco-santos

Diff for: README.md

@@ -17,11 +17,17 @@
 
 ## Table of Contents
 
-- [Install](#install)
-- [Usage](#usage)
-- [API](#api)
-- [Contribute](#contribute)
-- [License](#license)
+  - [Lead Maintainer](#lead-maintainer)
+  - [Table of Contents](#table-of-contents)
+    - [Install](#install)
+  - [Usage](#usage)
+  - [API](#api)
+      - [Setup](#setup)
+      - [Get](#get)
+      - [Put](#put)
+      - [Unsubscribe](#unsubscribe)
+  - [Contribute](#contribute)
+  - [License](#license)
 
 ### Install
 
@@ -62,22 +68,21 @@ const dsPubsub = new DatastorePubsub(pubsub, datastore, peerId, validator)
 #### Get
 
 ```js
-dsPubsub.get(key, callback)
+const buf = await dsPubsub.get(key)
 ```
 
 Try to subscribe a topic with Pubsub and receive the current local value if available.
 
 Arguments:
 
 - `key` (Buffer): a key representing a unique identifier of the object to subscribe.
-- `callback` (function): operation result.
 
-`callback` must follow `function (err, data) {}` signature, where `err` is an error if the operation was not successful. If no `err` is received, a `data` is received containing the most recent known record stored (`Buffer`).
+Returns `Promise<Buffer>` containing the most recent known record stored.
 
 #### Put
 
 ```js
-dsPubsub.put(key, val, callback)
+await dsPubsub.put(key, val)
 ```
 
 Publishes a value through pubsub.
@@ -86,14 +91,13 @@ Arguments:
 
 - `key` (Buffer): a key representing a unique identifier of the object to publish.
 - `val` (Buffer): value to be propagated.
-- `callback` (function): operation result.
 
-`callback` must follow `function (err) {}` signature, where `err` is an error if the operation was not successful.
+Returns `Promise<void>`
 
 #### Unsubscribe
 
 ```js
-dsPubsub.unsubscribe(key, callback)
+await dsPubsub.unsubscribe(key)
 ```
 
 Unsubscribe a previously subscribe value.
@@ -102,6 +106,8 @@ Arguments:
 
 - `key` (Buffer): a key representing a unique identifier of the object to publish.
 
+Returns `Promise<void>`
+
 ## Contribute
 
 Feel free to join in. All welcome. Open an [issue](https://github.com/ipfs/js-ipns/issues)!

Diff for: package.json

@@ -32,22 +32,23 @@
   },
   "homepage": "https://github.com/ipfs/js-datastore-pubsub#readme",
   "dependencies": {
-    "assert": "^1.4.1",
-    "async": "^2.6.2",
     "debug": "^4.1.1",
-    "err-code": "^1.1.2",
-    "interface-datastore": "~0.6.0",
+    "err-code": "^2.0.0",
+    "interface-datastore": "~0.7.0",
     "multibase": "~0.6.0"
   },
   "devDependencies": {
-    "aegir": "^18.1.1",
+    "aegir": "^20.0.0",
     "chai": "^4.2.0",
+    "delay": "^4.3.0",
     "detect-node": "^2.0.4",
     "dirty-chai": "^2.0.1",
-    "ipfs": "~0.34.4",
-    "ipfsd-ctl": "~0.42.0",
-    "libp2p-record": "~0.6.2",
-    "sinon": "^7.2.4"
+    "ipfs": "~0.37.0",
+    "ipfs-http-client": "^33.0.0",
+    "ipfsd-ctl": "^0.47.2",
+    "libp2p-record": "~0.7.0",
+    "promisify-es6": "^1.0.3",
+    "sinon": "^7.4.1"
   },
   "contributors": [
     "Vasco Santos <vasco.santos@ua.pt>",