=== Conditions in conditional flows

As was mentioned in <<_execution-requirements, Execution requirements>>, _Condition_ executions can be only contained in _Conditional_ subflow.
If all _Condition_ executions evaluate as true, then the _Conditional_ sub-flow acts as _Required_.
You can process the next execution in the _Conditional_ sub-flow.
If some executions included in the _Conditional_ sub-flow evaluate as false, then the whole sub-flow is considered as _Disabled_.

==== Available conditions

`Condition - User Role`::
This execution has the ability to determine if the user has a role defined by _User role_ field.
If the user has the required role, the execution is considered as true and other executions are evaluated.
The administrator has to define the following fields:

Alias:::
Describes a name of the execution, which will be shown in the authentication flow.

User role:::
Role the user should have to execute this flow.
To specify an application role the syntax is `appname.approle` (for example `myapp.myrole`).

`Condition - User Configured`::
This checks if the other executions in the flow are configured for the user.
The Execution requirements section includes an example of the OTP form.

`Condition - User Attribute`::
This checks if the user has set up the required attribute.
There is a possibility to negate output, which means the user should not have the attribute.
The xref:proc-configuring-user-attributes_{context}[User Attributes] section shows how to add a custom attribute.
You can provide these fields:

Alias:::
Describes a name of the execution, which will be shown in the authentication flow.

Attribute name:::
Name of the attribute to check.

Expected attribute value:::
Expected value in the attribute.

Negate output:::
You can negate the output.
In other words, the attribute should not be present.

==== Explicitly deny/allow access in conditional flows

You can allow or deny access to resources in a conditional flow.
The two authenticators `Deny Access` and `Allow Access` control access to the resources by conditions.

`Allow Access`::
Authenticator will always successfully authenticate.
This authenticator is not configurable.

`Deny Access`::
Access will always be denied.
You can define an error message, which will be shown to the user.
You can provide these fields:

Alias:::
Describes a name of the execution, which will be shown in the authentication flow.

Error message:::
Error message which will be shown to the user.
The error message could be provided as a particular message or as a property in order to use it with localization.
(i.e. "_You do not have the role 'admin'._", _my-property-deny_ in messages properties)
Leave blank for the default message defined as property `access-denied`.

Here is an example how to deny access to all users who do not have the role `role1` and show an error message defined by a property `deny-role1`.
This example includes `Condition - User Role` and `Deny Access` executions.

.Browser flow
image:images/deny-access-flow.png[Deny access flow]

.Condition - user role configuration
image:images/deny-access-role-condition.png[Deny access role settings]

.Configuration of the `Deny Access` is really easy. You can specify an arbitrary Alias and required message like this:
image:images/deny-access-execution-cond.png[Deny access execution settings]

The last thing is defining the property with an error message in the login theme `messages_en.properties` (for English):

[source]
----
deny-role1 = You do not have required role!
----