Fix/1178 mollie plugin

plugins/mollie/README.md

@@ -1,23 +1,32 @@
-FoodsoftMollie
-==============
+# FoodsoftMollie
 
-This project adds support for various online payment methods using Mollie to Foodsoft.
 
-* Make sure the gem is uncommented in foodsoft's `Gemfile`
-* Enter your Mollie account details in `config/app_config.yml`
+This plugin adds support for various online payment methods to Foodsoft, using [Mollie](https://www.mollie.com), a Dutch payment provider who offers this service in the European Economic Area (EEA).
+
+> Currently, `v1.0.1` ONLY iDEAL payments are supported
+
+## Setup
+
+* Make sure the `Mollie` gem is uncommented in foodsoft's [Gemfile](../../Gemfile).
+* Enter your Mollie account details in [config/app_config.yml](../../config/app_config.yml)`
 
 ```yaml
+  # Enable the plugin option
   use_mollie: true
   # Mollie payment settings
   mollie:
-    # API key for account: 1234567, website profile: FooInc
+    # API key for account as is provided by Mollie (check your Mollie dashboard)
     api_key: test_1234567890abcdef1234567890abcd
-    # Transaction fee as provided by mollie api (only EUR supported)
+    # Charge transaction fee as provided by mollie api 
+    # When false: fees are not added to the total amount so the coop will pay any fee related to the transaction
     charge_fees: true
-    currency: EUR # should match the foodcoop's currency
+    # Tax to apply on the fee (which is communicated by Mollie without tax!!)
+    tax: 21
+    # Only EUR supported (in the plugin at this time, Mollie does support other currencies) so this has to match the foodcoop's currency
+    currency: EUR
 ```
 
-When charge_fees is set true, the transaction fee will be added on each payment. At the moment fees are only supported with EUR.
+When charge_fees is set `true`, the transaction fee will be added on each payment. At the moment fees are only supported with EUR.
 It is disabled by default, meaning that the foodcoop will pay any transaction costs (out of the margin).
 
 To initiate a payment, redirect to `new_payments_mollie_path` at `/:foodcoop/payments/mollie/new`.
@@ -31,3 +40,37 @@ The following url parameters are recognised:
 This plugin also introduces the foodcoop config option `use_mollie`, which can
 be set to `false` to disable this plugin's functionality. May be useful in
 multicoop deployments.
+
+## Testing
+
+For testing it is helpful to allow Mollie to execute the callback, assuming you have an endpoint which can be reached, e.g. external address. See also [SSL](#ssl) as that is required by the Mollie callback.
+
+For this to work: add a file `callback_url.txt` in the `tmp` folder with a single line:
+
+```txt
+https://<your_external.address>
+```
+
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+!!! BE SURE TO USE THE MOLLIE TEST API_KEY WHEN TESTING
+!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+## SSL
+
+For properly testing Mollie with callbacks, `SSL/TLS` is required. 
+See for instance [Let's Encrypt](https://letsencrypt.org/docs/client-options/) to generate and configure SSL.
+
+We assume the default Webserver (Puma) here.
+
+> See your specific webserver, like Apache or Nginx, for details. 
+
+Start `RAILS` with SSL. 
+
+```bash
+bundle exec rails server --binding=0.0.0.0 -b 'ssl://0.0.0.0:3001?key=<some local place>/local-certs/privkey.pem&cert=some local place>/local-certs/fullchain.pem'
+```
+
+> !! Be aware that you should NEVER commit your certificates to the repository!!  
+
+Check the status to see if the webserver did start with SSL.
+Connect using `https://<your_external.address>/`