Update app to run on Ruby v3

Gemfile

@@ -7,3 +7,4 @@ gem 'dotenv'
 gem 'jwt'
 gem 'xero-ruby'
 gem 'byebug'
+gem 'rackup'

Gemfile.lock

@@ -1,95 +1,106 @@
 GIT
   remote: https://github.com/sinatra/sinatra.git
-  revision: f57acefddade9710d7ca3c7a508d4484e90aacdd
+  revision: e56f657bed6c3b1cb5492e7a8cf995013c4388b5
   specs:
-    rack-protection (2.1.0)
-      rack
-    sinatra (2.1.0)
-      mustermann (~> 1.0)
-      rack (~> 2.2)
-      rack-protection (= 2.1.0)
-      tilt (~> 2.0)
-    sinatra-contrib (2.1.0)
-      multi_json
-      mustermann (~> 1.0)
-      rack-protection (= 2.1.0)
-      sinatra (= 2.1.0)
+    rack-protection (3.2.0)
+      base64 (>= 0.1.0)
+      rack (>= 3.0.0, < 4)
+    sinatra (3.2.0)
+      mustermann (~> 3.0)
+      rack (>= 3.0.0, < 4)
+      rack-protection (= 3.2.0)
+      rack-session (>= 2.0.0, < 3)
       tilt (~> 2.0)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (7.0.2.3)
+    activesupport (7.1.2)
+      base64
+      bigdecimal
       concurrent-ruby (~> 1.0, >= 1.0.2)
+      connection_pool (>= 2.2.5)
+      drb
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
+      mutex_m
       tzinfo (~> 2.0)
     aes_key_wrap (1.1.0)
-    bindata (2.4.10)
+    base64 (0.2.0)
+    bigdecimal (3.1.5)
+    bindata (2.4.15)
     byebug (11.1.3)
-    concurrent-ruby (1.1.10)
-    dotenv (2.7.6)
-    faraday (1.10.0)
-      faraday-em_http (~> 1.0)
-      faraday-em_synchrony (~> 1.0)
-      faraday-excon (~> 1.1)
-      faraday-httpclient (~> 1.0)
-      faraday-multipart (~> 1.0)
-      faraday-net_http (~> 1.0)
-      faraday-net_http_persistent (~> 1.0)
-      faraday-patron (~> 1.0)
-      faraday-rack (~> 1.0)
-      faraday-retry (~> 1.0)
-      ruby2_keywords (>= 0.0.4)
-    faraday-em_http (1.0.0)
-    faraday-em_synchrony (1.0.0)
-    faraday-excon (1.1.0)
-    faraday-httpclient (1.0.1)
-    faraday-multipart (1.0.3)
-      multipart-post (>= 1.2, < 3)
-    faraday-net_http (1.0.1)
-    faraday-net_http_persistent (1.2.0)
-    faraday-patron (1.0.0)
-    faraday-rack (1.0.0)
-    faraday-retry (1.0.3)
-    haml (5.1.2)
-      temple (>= 0.8.0)
+    concurrent-ruby (1.2.3)
+    connection_pool (2.4.1)
+    dotenv (2.8.1)
+    drb (2.2.0)
+      ruby2_keywords
+    faraday (2.9.0)
+      faraday-net_http (>= 2.0, < 3.2)
+    faraday-follow_redirects (0.3.0)
+      faraday (>= 1, < 3)
+    faraday-net_http (3.1.0)
+      net-http
+    haml (6.3.0)
+      temple (>= 0.8.2)
+      thor
       tilt
-    i18n (1.10.0)
+    i18n (1.14.1)
       concurrent-ruby (~> 1.0)
-    json (2.6.1)
-    json-jwt (1.13.0)
+    json (2.7.1)
+    json-jwt (1.16.5)
       activesupport (>= 4.2)
       aes_key_wrap
+      base64
       bindata
-    jwt (2.3.0)
-    minitest (5.15.0)
-    multi_json (1.14.1)
-    multipart-post (2.1.1)
-    mustermann (1.1.1)
+      faraday (~> 2.0)
+      faraday-follow_redirects
+    jwt (2.7.1)
+    minitest (5.21.1)
+    multi_json (1.15.0)
+    mustermann (3.0.0)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.3)
+    mutex_m (0.2.0)
+    net-http (0.4.1)
+      uri
+    rack (3.0.8)
+    rack-session (2.0.0)
+      rack (>= 3.0.0)
+    rackup (2.1.0)
+      rack (>= 3)
+      webrick (~> 1.8)
     ruby2_keywords (0.0.5)
-    temple (0.8.2)
-    tilt (2.0.10)
-    tzinfo (2.0.4)
+    sinatra-contrib (3.2.0)
+      multi_json (>= 0.0.2)
+      mustermann (~> 3.0)
+      rack-protection (= 3.2.0)
+      sinatra (= 3.2.0)
+      tilt (~> 2.0)
+    temple (0.10.3)
+    thor (1.3.0)
+    tilt (2.3.0)
+    tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    xero-ruby (3.7.1)
-      faraday (~> 1.0, >= 1.0.1)
+    uri (0.13.0)
+    webrick (1.8.1)
+    xero-ruby (4.3.1)
+      faraday (>= 2.0, < 3.0)
       json (~> 2.1, >= 2.1.0)
-      json-jwt (~> 1.5, >= 1.5.2)
+      json-jwt (~> 1.16, >= 1.16.3)
 
 PLATFORMS
+  arm64-darwin-23
   ruby
 
 DEPENDENCIES
   byebug
   dotenv
   haml
   jwt
+  rackup
   sinatra!
   sinatra-contrib
   xero-ruby
 
 BUNDLED WITH
-   2.3.9
+   2.5.4

README.md

@@ -3,10 +3,10 @@ This is a basic application showing how to get started with the Xero's official
 *It uses [Sinatra](https://github.com/sinatra/sinatra) which is a DSL for creating simple web applications in Ruby with minimal effort*
 
 # Getting Started
-### 1) Make sure you have at least Ruby 2.7 [installed](https://www.ruby-lang.org/en/documentation/installation/)
+### 1) This app is tested with Ruby [3.3.0](https://www.ruby-lang.org/en/documentation/installation/)
 ```bash
 ruby -v
-ruby 2.7.0
+ruby 3.3.0
 ```
 
 ### 2) Create an app in Xero's developer portal

views/layout.haml

@@ -11,7 +11,7 @@
 
       .flex-container
         .main
-          = yield
+          = yield.html_safe
         %nav.sidebar-nav
           %ul
             %li