Additional OAuth2 providers (#1010)

* add google+

* sort signin oauth2 providers based on the name so order is always the same

* update auth tip for google+

* add gitlab provider

* add bitbucket provider (and some go fmt)

* add twitter provider

* add facebook provider

* add dropbox provider

* add openid connect provider incl. new format of tips section in "Add New Source"

* lower the amount of disk storage for each session to prevent issues while building cross platform (and disk overflow)

* imports according to goimport and code style

* make it possible to set custom urls to gitlab and github provider (only these could have a different host)

* split up oauth2 into multiple files

* small typo in comment

* fix indention

* fix indentation

* fix new line before external import

* fix layout of signin part

* update "broken" dependency

3 files changed, 92 insertions, 3 deletions

diff --git a/templates/admin/auth/edit.tmpl b/templates/admin/auth/edit.tmpl
index ea5104b79f..3c74b2ad17 100644
--- a/templates/admin/auth/edit.tmpl
+++ b/templates/admin/auth/edit.tmpl
@@ -164,6 +164,39 @@
 						<label for="oauth2_secret">{{.i18n.Tr "admin.auths.oauth2_clientSecret"}}</label>
 						<input id="oauth2_secret" name="oauth2_secret" value="{{$cfg.ClientSecret}}" required>
 					</div>
+					<div class="open_id_connect_auto_discovery_url required field">
+						<label for="open_id_connect_auto_discovery_url">{{.i18n.Tr "admin.auths.openIdConnectAutoDiscoveryURL"}}</label>
+						<input id="open_id_connect_auto_discovery_url" name="open_id_connect_auto_discovery_url" value="{{$cfg.OpenIDConnectAutoDiscoveryURL}}">
+					</div>
+
+					<div class="oauth2_use_custom_url inline field">
+						<div class="ui checkbox">
+							<label><strong>{{.i18n.Tr "admin.auths.oauth2_use_custom_url"}}</strong></label>
+							<input id="oauth2_use_custom_url" name="oauth2_use_custom_url" type="checkbox" {{if $cfg.CustomURLMapping}}checked{{end}}>
+						</div>
+					</div>
+					<div class="oauth2_use_custom_url_field oauth2_auth_url required field">
+						<label for="oauth2_auth_url">{{.i18n.Tr "admin.auths.oauth2_authURL"}}</label>
+						<input id="oauth2_auth_url" name="oauth2_auth_url" value="{{if $cfg.CustomURLMapping}}{{$cfg.CustomURLMapping.AuthURL}}v{{end}}">
+					</div>
+					<div class="oauth2_use_custom_url_field oauth2_token_url required field">
+						<label for="oauth2_token_url">{{.i18n.Tr "admin.auths.oauth2_tokenURL"}}</label>
+						<input id="oauth2_token_url" name="oauth2_token_url" value="{{if $cfg.CustomURLMapping}}{{$cfg.CustomURLMapping.TokenURL}}{{end}}">
+					</div>
+					<div class="oauth2_use_custom_url_field oauth2_profile_url required field">
+						<label for="oauth2_profile_url">{{.i18n.Tr "admin.auths.oauth2_profileURL"}}</label>
+						<input id="oauth2_profile_url" name="oauth2_profile_url" value="{{if $cfg.CustomURLMapping}}{{$cfg.CustomURLMapping.ProfileURL}}{{end}}">
+					</div>
+					<div class="oauth2_use_custom_url_field oauth2_email_url required field">
+						<label for="oauth2_email_url">{{.i18n.Tr "admin.auths.oauth2_emailURL"}}</label>
+						<input id="oauth2_email_url" name="oauth2_email_url" value="{{if $cfg.CustomURLMapping}}{{$cfg.CustomURLMapping.EmailURL}}{{end}}">
+					</div>
+					{{if .OAuth2DefaultCustomURLMappings}}{{range $key, $value := .OAuth2DefaultCustomURLMappings}}
+					<input id="{{$key}}_token_url" value="{{$value.TokenURL}}" type="hidden" />
+					<input id="{{$key}}_auth_url" value="{{$value.AuthURL}}" type="hidden" />
+					<input id="{{$key}}_profile_url" value="{{$value.ProfileURL}}" type="hidden" />
+					<input id="{{$key}}_email_url" value="{{$value.EmailURL}}" type="hidden" />
+					{{end}}{{end}}
 				{{end}}
 
 				<div class="inline field {{if not .Source.IsSMTP}}hide{{end}}">
diff --git a/templates/admin/auth/new.tmpl b/templates/admin/auth/new.tmpl
index a18a782fc1..00239b0462 100644
--- a/templates/admin/auth/new.tmpl
+++ b/templates/admin/auth/new.tmpl
@@ -80,8 +80,29 @@
 		<div class="ui attached segment">
 			<h5>GMail Settings:</h5>
 			<p>Host: smtp.gmail.com, Port: 587, Enable TLS Encryption: true</p>
-			<h5>OAuth GitHub:</h5>
-			<p>{{.i18n.Tr "admin.auths.tip.github"}}</p>
+
+			<h5>{{.i18n.Tr "admin.auths.tips.oauth2.general"}}:</h5>
+			<p>{{.i18n.Tr "admin.auths.tips.oauth2.general.tip"}}</p>
+
+			<h5 class="ui top attached header">{{.i18n.Tr "admin.auths.tip.oauth2_provider"}}</h5>
+			<div class="ui attached segment">
+				<li>Bitbucket</li>
+				<span>{{.i18n.Tr "admin.auths.tip.bitbucket"}}</span>
+				<li>Dropbox</li>
+				<span>{{.i18n.Tr "admin.auths.tip.dropbox"}}</span>
+				<li>Facebook</li>
+				<span>{{.i18n.Tr "admin.auths.tip.facebook"}}</span>
+				<li>GitHub</li>
+				<span>{{.i18n.Tr "admin.auths.tip.github"}}</span>
+				<li>GitLab</li>
+				<span>{{.i18n.Tr "admin.auths.tip.gitlab"}}</span>
+				<li>Google+</li>
+				<span>{{.i18n.Tr "admin.auths.tip.google_plus"}}</span>
+				<li>OpenID Connect</li>
+				<span>{{.i18n.Tr "admin.auths.tip.openid_connect"}}</span>
+				<li>Twitter</li>
+				<span>{{.i18n.Tr "admin.auths.tip.twitter"}}</span>
+			</div>
 		</div>
 	</div>
 </div>
diff --git a/templates/admin/auth/source/oauth.tmpl b/templates/admin/auth/source/oauth.tmpl
index 4d8e12e028..5d585c04dc 100644
--- a/templates/admin/auth/source/oauth.tmpl
+++ b/templates/admin/auth/source/oauth.tmpl
@@ -20,4 +20,39 @@
 		<label for="oauth2_secret">{{.i18n.Tr "admin.auths.oauth2_clientSecret"}}</label>
 		<input id="oauth2_secret" name="oauth2_secret" value="{{.oauth2_secret}}">
 	</div>
-</div>
+	<div class="open_id_connect_auto_discovery_url required field">
+		<label for="open_id_connect_auto_discovery_url">{{.i18n.Tr "admin.auths.openIdConnectAutoDiscoveryURL"}}</label>
+		<input id="open_id_connect_auto_discovery_url" name="open_id_connect_auto_discovery_url" value="{{.open_id_connect_auto_discovery_url}}">
+	</div>
+
+	<div class="oauth2_use_custom_url inline field">
+		<div class="ui checkbox">
+			<label><strong>{{.i18n.Tr "admin.auths.oauth2_use_custom_url"}}</strong></label>
+			<input id="oauth2_use_custom_url" name="oauth2_use_custom_url" type="checkbox">
+		</div>
+	</div>
+	<div class="oauth2_use_custom_url_field oauth2_auth_url required field">
+		<label for="oauth2_auth_url">{{.i18n.Tr "admin.auths.oauth2_authURL"}}</label>
+		<input id="oauth2_auth_url" name="oauth2_auth_url" value="{{.oauth2_auth_url}}">
+	</div>
+	<div class="oauth2_use_custom_url_field oauth2_token_url required field">
+		<label for="oauth2_token_url">{{.i18n.Tr "admin.auths.oauth2_tokenURL"}}</label>
+		<input id="oauth2_token_url" name="oauth2_token_url" value="{{.oauth2_token_url}}">
+	</div>
+	<div class="oauth2_use_custom_url_field oauth2_profile_url required field">
+		<label for="oauth2_profile_url">{{.i18n.Tr "admin.auths.oauth2_profileURL"}}</label>
+		<input id="oauth2_profile_url" name="oauth2_profile_url" value="{{.oauth2_profile_url}}">
+	</div>
+	<div class="oauth2_use_custom_url_field oauth2_email_url required field">
+		<label for="oauth2_email_url">{{.i18n.Tr "admin.auths.oauth2_emailURL"}}</label>
+		<input id="oauth2_email_url" name="oauth2_email_url" value="{{.oauth2_email_url}}">
+	</div>
+	{{if .OAuth2DefaultCustomURLMappings}}
+		{{range $key, $value := .OAuth2DefaultCustomURLMappings}}
+			<input id="{{$key}}_token_url" value="{{$value.TokenURL}}" type="hidden" />
+			<input id="{{$key}}_auth_url" value="{{$value.AuthURL}}" type="hidden" />
+			<input id="{{$key}}_profile_url" value="{{$value.ProfileURL}}" type="hidden" />
+			<input id="{{$key}}_email_url" value="{{$value.EmailURL}}" type="hidden" />
+		{{end}}
+	{{end}}
+</div>
\ No newline at end of file