allow configuring saml in configuration.yml

modules/auth_saml/README.md

@@ -4,27 +4,76 @@
 
 This plugin provides the [OmniAuth SAML strategy](https://github.com/omniauth/omniauth-saml) into OpenProject.
 
-## Installation
+## Configuration
 
-Add the following entries to your `Gemfile.plugins` in your OpenProject root directory:
+The configuration can be provided in one of three ways:
 
-    gem 'openproject-auth_plugins', git: 'https://github.com/finnlabs/openproject-auth_plugins', branch: 'stable'
-    gem "openproject-auth_saml", git: 'https://github.com/finnlabs/openproject-auth_saml', branch: 'stable'
+* configuration.yml file
+* Environment variables
+* settings.yml file
 
-## Requirements
+Whatever means are chosen, the plugin simply passes all options to omniauth-saml. See [their configuration
+documentation](https://github.com/omniauth/omniauth-saml#usage) for further details.
 
-* [omniauth-saml gem](https://github.com/omniauth/omniauth-saml) >= 1.4.0
-* [OpenProject](https://www.openproject.org) >= 5.0
-* [openproject-auth_plugins](https://github.com/opf/openproject-auth_plugins)
+### configuration.yml file
 
-## Configuration
+The file
+
+```bash
+config/configuration.yml
+```
+
+can be extended to include the necessary settings. Everything belonging to the `saml` key will be made available to the plugin.
+
+```yaml
+saml:
+  my_saml:
+    name: "your-provider-name"
+    display_name: "My SAML provider"
+    # Use the default SAML icon
+    icon: "auth_provider-saml.png"
+    # omniauth-saml config
+    assertion_consumer_service_url: "consumer_service_url"
+    issuer: "issuer"
+    idp_sso_target_url: "idp_sso_target_url"
+    idp_cert_fingerprint: "E7:91:B2:E1:..."
+    attribute_statements:
+      email: ['mailPrimaryAddress']
+      name: ['gecos']
+      first_name: ['givenName']
+      last_name: ['sn']
+      admin: ['openproject-isadmin']
+```
+
+### Environment variables
+
+As with all the rest of the OpenProject configuration settings, the saml configuration can be provided via environment variables.
+
+E.g.
+
+```bash
+OPENPROJECT_SAML_MY__SAML_NAME="your-provider-name"
+OPENPROJECT_SAML_MY__SAML_DISPLAY__NAME="My SAML provider"
+...
+OPENPROJECT_SAML_MY__SAML_ATTRIBUTE__STATEMENTS_ADMIN="['openproject-isadmin']"
+```
+
+Please note that every underscore (`_`) in the original configuration key has to be replaced by a duplicate underscore
+(`__`) in the environment variable as the single underscore denotes namespaces.
+
+### settings.yml file
+
+For backwards compatibility, having a dedicated settings.yml is also supported.
 
 To add your own SAML strategy provider(s), create the following settings file (relative to your OpenProject root):
 
+```bash
 config/plugins/auth_saml/settings.yml
+```
 	
 with the following contents:
 
+```yaml
 your-provider-name:
   name: "your-provider-name"
   display_name: "My SAML provider"
@@ -41,6 +90,7 @@ with the following contents:
     first_name: ['givenName']
     last_name: ['sn']
     admin: ['openproject-isadmin']
+```
 
 The plugin simply passes all options to omniauth-saml. See [their configuration
 documentation](https://github.com/omniauth/omniauth-saml#usage) for further
@@ -51,14 +101,6 @@ details.
 To add a custom icon to be rendered as your omniauth provider icon, add an
 image asset to OpenProject and reference it in your `settings.yml`:
 
+```bash
 icon: "my/asset/path/to/icon.png"
-	
-## Copyrights & License
-
-OpenProject SAML Auth is completely free and open source and released under the
-[MIT
-License](https://github.com/finnlabs/openproject-auth_saml/blob/dev/LICENSE).
-
-Copyright (c) 2016 OpenProject GmbH
-
-The default provider icon is a combination of icons from [Font Awesome by Dave Gandy](http://fontawesome.io).
+```

modules/auth_saml/lib/open_project/auth_saml/engine.rb

@@ -31,12 +31,19 @@ module OpenProject
       end
 
       register_auth_providers do
-        settings = Rails.root.join('config', 'plugins', 'auth_saml', 'settings.yml')
-        if settings.exist?
-          Rails.logger.info("[auth_saml] Registering saml integration from 'config/plugins/auth_saml/settings.yml'")
-          providers = YAML::load(File.open(settings)).symbolize_keys
+        configuration = if OpenProject::Configuration['saml'].present?
+                          Rails.logger.info("[auth_saml] Registering saml integration from configuration.yml")
+
+                          OpenProject::Configuration['saml']
+                        elsif (settings = Rails.root.join('config', 'plugins', 'auth_saml', 'settings.yml')).exist?
+                          Rails.logger.info("[auth_saml] Registering saml integration from settings file")
+
+                          YAML::load(File.open(settings)).symbolize_keys
+                        end
+
+        if configuration
           strategy :saml do
-            providers.values.map do |h|
+            configuration.values.map do |h|
               h[:openproject_attribute_map] = Proc.new do |auth|
                 {
                   login: auth[:uid],