Create device groups
Create a device group that matches the User-Agent header in Azion Console, then confirm it with a rule that adds a response header.
You can create a device group for an application in Azion Console, then confirm it with a rule that marks the responses to that group. A device group pairs a name with a regular expression, and the application compares the expression with the User-Agent header of each request.
To keep a separate cached copy of each object for every device group, set the variation in a cache setting instead. For more information, refer to Application Accelerator settings.
Prerequisites
- An application served by a workload. To create both, refer to Applications quickstart.
- Application Accelerator turned on for the application. The rule on this page reads the
${device_group}variable, which requires it. To turn it on, refer to Main Settings. - Access to Azion Console. To sign in, refer to Access Azion Console.
Create the device group
The device group in this section is named Mobile. Its expression matches any User-Agent header that contains Mobile, iPhone, or Android, because a match on part of the header is enough. Each application keeps its own device groups, in its Device Groups tab.
To create the device group in Azion Console:
Access Azion Console > Applications, and select the application.
In Name, enter Mobile. The name takes letters and numbers only, with no spaces. For any other character, the Console shows Name must be alphanumeric.
In the Match to User-Agent section, enter (Mobile|iPhone|Android) as the Regular Expression.
Azion Console shows Device Group successfully created, and the group appears in the Device Groups tab. For each field of a device group and the messages the form shows, refer to Device Groups.
Match the device group in a rule
A rule that reads ${device_group} applies its behaviors only to the requests of one device group. The rule in this section runs in the Response Phase. It adds the header Device-Is: Mobile device to each response sent to the Mobile group, so a response shows whether the group matched its request. The rule is a check: once the group is confirmed, you change its behavior or turn it off.
To create the rule in Azion Console:
Access Azion Console > Applications, and select the application.
In General, enter Device Group: Mobile as the Name.
In Phase, select Response Phase. A rule’s phase cannot change after you create the rule.
Under Criteria, select the variable ${device_group} and the operator is_equal, and enter Mobile as the argument.
Under Behaviors, select the behavior that adds a header to the response. In the API, its type is add_response_header.
Enter Device-Is: Mobile device as the argument. The Console refuses an argument that is not in the header-name: value format.
The rule appears in the Rules Engine tab, under the Response heading. For every variable, operator, and behavior a rule accepts, refer to Rules Engine for Applications.
Confirm the device group
The rule that reads ${device_group} marks each response to the Mobile group, so one request confirms whether the group matches a device. Send the request to the application from a device that the expression matches. A browser on a mobile device works, and so does any client that sets the User-Agent header to a matching value, such as iPhone Android.
The response carries the header the rule adds, device-is: Mobile device. A request whose User-Agent header the expression does not match receives no such header.
A new rule can take a few minutes to take effect, and until then no response carries the header. Send the request again before you change the rule or the expression.
Once the header appears, the device group is confirmed. Replace the behavior of the rule with the one the group is for, or turn off Active in the Status section of the rule so that it stops running. For more information, refer to Create an application rule.