add discovery topics to reorg (#117)

* add discovery topics to reorg
* added PayID discovery to sidebar
* Newline removed.
I need to get actual names for scenarios that are legally approved. Will do so in the near future.

Author: LoisRP

docs/payid-discovery.md

@@ -0,0 +1,45 @@
+---
+id: payid-discovery
+title: Discover a PayID
+sidebar_label: Discover a PayID
+---
+
+The PayID Discovery endpoint facilitates finding the PayID URI for a given PayID.
+
+## PayID discovery by a wallet application
+
+Suppose Alice wants to send Bob some XRP from a web-based wallet provider that Alice has an account on. Alice logs in to the wallet provider and enter Bob's PayID, such as `bob$receiver.example.com`, into the wallet UI to start the payment. If the wallet application is set up to use the PayID Discovery endpoint, the wallet application performs a WebFinger query that looks for the PayID Discovery service provider, like this:
+
+```
+GET /.well-known/webfinger?resource=payid%3Abob%24receiver.example.com
+HTTP/1.1
+Host: receiver.example.com
+```
+
+If the server for Bob's exchange, where Bob receives currency, supports the PayID Discovery endpoint, it responds like this:
+
+```
+ HTTP/1.1 200 OK
+ Access-Control-Allow-Origin: *
+ Content-Type: application/jrd+json
+
+ {
+   "subject" : "payid:bob$receiver.example.com",
+   "links" :
+   [
+     {
+       "rel": "https://payid.org/ns/payid-uri-template/1.0",
+       "template": "https://receiver.example.com/users/{acctpart}"
+     }
+   ]
+ }
+```
+
+Alice's wallet can then use the URL template found in the "template" property to assemble the specified PayId URL. Typically, this template might add a folder structure to the URL, such as `https://receiver.example.com/users/bob`. The server can be set up to use other URL formats, so long as the resulting URL is valid and represents Bob's PayID.
+
+## PayID discovery with a default template
+
+In this case, Alice's wallet application makes the same request as previously, but Bob's server does not support Webfinger, and returns `HTTP/1.1 404 NOT FOUND`.
+
+The wallet application then uses a default template to transform `bob$receiever.example.com`
+to `https://receiver.example.com/bob`. The wallet then uses this URL to continue making the payment. Alice's wallet proceeds to make the payment.

sidebars.js

@@ -21,6 +21,7 @@ module.exports = {
         'payid-reference-overview',
         'payid-cli',
         'verifiable-payid',
+        'payid-discovery',
         'payid-best-practices',
         'integrate-payid-users',
         'metrics',