Replace regex for reading AWS files with iniparse

Gemfile

@@ -7,6 +7,7 @@ group :development do
   # gem dependency because we expect to be installed within the
   # Vagrant environment itself using `vagrant plugin`.
   gem "vagrant", :git => "https://github.com/mitchellh/vagrant.git"
+  gem 'iniparse', '~> 1.4', '>= 1.4.2'
 end
 
 group :plugins do

lib/vagrant-aws/config.rb

@@ -1,4 +1,5 @@
 require "vagrant"
+require "iniparse"
 
 module VagrantPlugins
   module AWS
@@ -505,7 +506,9 @@ module VagrantPlugins
             aws_config = location + 'config'
             aws_creds = location + 'credentials'
           end
-          aws_region, aws_id, aws_secret, aws_token = read_aws_files(profile, aws_config, aws_creds)
+          if File.exist?(aws_config) and File.exist?(aws_creds)
+            aws_region, aws_id, aws_secret, aws_token = read_aws_files(profile, aws_config, aws_creds)
+          end
         end
         aws_region = nil if aws_region == ''
         aws_id     = nil if aws_id == ''
@@ -519,37 +522,25 @@ module VagrantPlugins
       private
 
       def read_aws_files(profile, aws_config, aws_creds)
-        # profile line to match in the config file
-        pat = ''
+        # determine section in config ini file
         if profile == 'default'
-          pat = '\[default\]'
+          ini_profile = profile
         else
-          pat = '\[profile ' + profile + '\]'
-        end
-        # read config file for selected profile
-        begin
-          data = File.read(aws_config)
-          regex = Regexp.new('^' + pat + '$\n^region\s*=\s*(.*)$')
-          aws_region = regex.match(data)[1]
-        rescue
-          aws_region = ''
+          ini_profile = 'profile ' + profile
         end
+        # get info from config ini file for selected profile
+        data = File.read(aws_config)
+        doc_cfg = IniParse.parse(data)
+        aws_region = doc_cfg[ini_profile]['region']
 
-        # profile line to match in the credentials file
-        pat = '\[' + profile + '\]'
-        # read credentials file for selected profile
-        begin
-          aws_token = ''
-          data = File.read(aws_creds)
-          regex = Regexp.new('^' + pat + '$\n^aws_access_key_id\s*=\s*(.*)$\naws_secret_access_key\s*=\s*(.*)$(\n^aws_session_token\s*=\s*(.*)$)?')
-          matches = regex.match(data)
-          aws_id = matches[1]
-          aws_secret = matches[2]
-          aws_token = matches[4]
-        rescue
-          aws_id = ''
-          aws_secret = ''
-        end
+        # determine section in credentials ini file
+        ini_profile = profile
+        # get info from credentials ini file for selected profile
+        data = File.read(aws_creds)
+        doc_cfg = IniParse.parse(data)
+        aws_id = doc_cfg[ini_profile]['aws_access_key_id']
+        aws_secret = doc_cfg[ini_profile]['aws_secret_access_key']
+        aws_token = doc_cfg[ini_profile]['aws_session_token']
 
         return aws_region, aws_id, aws_secret, aws_token
       end

spec/vagrant-aws/config_spec.rb

@@ -190,6 +190,7 @@ aws_session_token= TOKuser3
 
     context "without EC2 credential environment variables but with AWS_CONFIG_FILE and AWS_SHARED_CREDENTIALS_FILE set" do
       subject do
+        allow(File).to receive(:exist?).and_return(true)
         allow(File).to receive(:read).with(filename_cfg).and_return(data_cfg)
         allow(File).to receive(:read).with(filename_keys).and_return(data_keys)
         ENV.stub(:[]).with("AWS_CONFIG_FILE").and_return(sh_filename_cfg)
@@ -208,6 +209,7 @@ aws_session_token= TOKuser3
 
     context "without any credential environment variables and fallback to default profile at default location" do
       subject do
+        allow(File).to receive(:exist?).and_return(true)
         allow(File).to receive(:read).with(filename_cfg).and_return(data_cfg)
         allow(File).to receive(:read).with(filename_keys).and_return(data_keys)
         instance.tap do |o|
@@ -221,6 +223,7 @@ aws_session_token= TOKuser3
 
     context "without any credential environment variables and chosing a profile" do
       subject do
+        allow(File).to receive(:exist?).and_return(true)
         allow(File).to receive(:read).with(filename_cfg).and_return(data_cfg)
         allow(File).to receive(:read).with(filename_keys).and_return(data_keys)
         instance.aws_profile = "user3"