Rose Suite Configurations


The following documentation reflects installing and running a Cylc workflow, and assumes that you have Cylc and the Cylc Rose plugin installed.

To check:

$ cylc version --long
8.0.0 (/path/to/install)

      cylc-rose       1.0.0   ~/cylc-rose

Rose application configurations can be used to encapsulate the environment and resources required by a Cylc task.

Similarly Rose suite configurations can be used to do the same for a workflow.

Configuration Format

A Rose suite configuration is a Cylc source directory containing a rose-suite.conf file.

The rose-suite.conf file is written in the same format as the rose-app.conf file. Its main configuration sections are:


Environment variables for use by the workflow scheduler.

rose-suite.conf[template variables]

Generic variables for use in the flow.cylc file.


Files and resources to be installed in the run directory when the suite is run.


At Rose 2/Cylc 8, using the rose-suite.conf[template variables] section is the recommended way of working. Cylc will select a templating language based on the hashbang line at the start of the the flow.cylc file.

At Rose 2019/Cylc 7, these variables were instead set in sections called rose-suite.conf[jinja2:suite.rc] and rose-suite.conf[empy:suite.rc]. These are still supported to ease the transition to Rose 2, but should not be used for new suite configurations.

In the following example the template variable WORLD is set in the rose-suite.conf file. This can then be used in the flow.cylc file:

[template variables]
        R1 = hello_{{ WORLD }}

    [[hello_{{ WORLD }}]]
        script = echo "hello {{ WORLD }}"

Using a Rose workflow configuration with Cylc 8

See also

This section acts to demonstrate how Cylc 8 can be used to install Rose configurations for Cylc workflows. It is not designed to comprehensively explain the usage of Cylc.

Rose configurations are installed alongside Cylc workflows by cylc install, if a rose-suite.conf file is present.

Using a Rose Configuration for a Cylc 8 workflow.
# Assuming that the example above was developed in ~/cylc-src/my-workflow
cylc validate my-workflow    # Checks that the workflow configuration is valid
cylc install my-workflow     # Installs workflow to ~/cylc-run/my-workflow
cylc play my-workflow        # Plays the workflow.
cylc config my-workflow      # Look at the workflow with template vars filled in.


In this tutorial we will create a Rose Suite Configuration for the weather-forecasting workflow.

  1. Create a new Cylc workflow

    Create a copy of the weather-forecasting workflow by running:

    rose tutorial rose-suite-tutorial ~/cylc-src/rose-suite-tutorial
    cd ~/cylc-src/rose-suite-tutorial


    If you haven’t ever used Cylc 8 you may need to create the source directory. (mkdir ~/cylc-src)

  2. Create a Rose suite configuration

    Create a blank rose-suite.conf file:

    touch rose-suite.conf

    You now have a Rose suite configuration. A rose-suite.conf file does not need to have anything in it.

    There are three things defined in the flow.cylc file which it might be useful to be able to configure:


    The list of weather stations to gather observations from.


    The spatial resolution of the forecast model.


    The geographical limits of the model.

    Define these settings in the rose-suite.conf file by adding the following lines:

    [template variables]
    station="camborne", "heathrow", "shetland", "aldergrove"

    Note that template variable strings must be quoted.

  3. Tell the workflow what language to use when templating

    Add a hashbang line to the flow.cylc file to tell it to use Jinja2 to process template variables:

    + #!jinja2
        UTC mode = True
  4. Write suite metadata

    Create a meta/rose-meta.conf file and write some metadata for the settings defined in the rose-suite.conf file.

    • station is a list of unlimited length.

    • RESOLUTION is a “real” number.

    • DOMAIN is a list of four integers.


    [template variables=station]
    [template variables=RESOLUTION]
    [template variables=DOMAIN]

    Validate the metadata:

    rose metadata-check -C meta/

    Open the rose config-edit GUI. You should see suite conf in the panel on the left-hand side of the window. This will contain the template variables we have just defined.

  5. Use suite variables in the flow.cylc file

    Next we need to make use of these settings in the flow.cylc file.

    We need to change the RESOLUTION and DOMAIN settings in the [runtime][root][environment] section which would otherwise override the variables we have just defined in the rose-suite.conf file, like so:

             # These environment variables will be available to all tasks.
                 # The dimensions of each grid cell in degrees.
    -            RESOLUTION = 0.2
    +            RESOLUTION = {{ RESOLUTION }}
                 # The area to generate forecasts for (lng1, lat1, lng2, lat2).
    -            DOMAIN = -12,48,5,61  # Do not change!
    +            DOMAIN = {{ DOMAIN | join(", ") }}

    We have written out the DOMAIN list using the Jinja2 join filter to write the commas between the list items. We can do the same for station:

         UTC mode = True
     [task parameters]
        # A list of the weather stations we will be fetching observations from.
    -   station = camborne, heathrow, shetland, aldergrove
    +   station = {{ station | join(", ") }}
        # A list of the sites we will be generating forecasts for.
        site = exeter
  6. Install the workflow

    This workflow is not ready to play yet but you can check that it is valid with cylc validate:

    cylc validate .

    You can then install the workflow with cylc install:

    cylc install rose-suite-tutorial

    Inspect the installed workflow, which you will find in the run directory, i.e:


    You should find all the files, plus the log directory, contained in the run directory.

Rose Applications In Rose Suite Configurations

In Cylc workflows, Rose applications are placed in an app/ directory which is copied across to the run directory with the rest of the suite by cylc install when the workflow configuration is installed.

When we run Rose applications from within Cylc workflows we use the rose task-run command rather than the rose app-run command.

When run, rose task-run searches for an application with the same name as the Cylc task in the app/ directory.

The rose task-run command also interfaces with Cylc to provide a few useful environment variables (see the command-line reference for details). The application will run in the work directory, just like for a regular Cylc task.

In this example the hello task will run the application located in app/hello/:

        script = rose task-run
default=echo "Hello World!"

The name of the application to run can be overridden using the --app-key command-line option or the ROSE_TASK_APP environment variable. For example the greetings task will run the hello app in the task defined below.

        script = rose task-run --app-key hello


In this practical we will take the forecast Rose application that we developed in the Metadata Tutorial and integrate it into the weather-forecasting workflow.

Move into the workflow source directory from the previous practical:

cd ~/cylc-src/rose-suite-tutorial

You will find a copy of the forecast application located in app/forecast.

  1. Create a test configuration for the forecast application.

    The forecast application comes with test data (in file/test-date), and is currently set up to work with this data.

    We will now adjust this configuration to make it work with real data generated by the Cylc workflow. It is useful to keep the ability to run the application using test data, so we won’t delete this configuration. Instead we will move it into an Optional Configuration so that we can run the application in “test mode” or “live mode”.

    Optional configurations are covered in more detail in the Optional Configurations Tutorial. For now all we need to know is that they enable us to store alternative configurations.

    Create an optional configuration called test inside the forecast application:

    mkdir app/forecast/opt
    touch app/forecast/opt/rose-app-test.conf

    This optional configuration is a regular Rose configuration file. Its settings will override those in the rose-app.conf file if requested.


    Take care not to confuse the rose-app.conf and rose-app-test.conf files used within this practical.

    Move the following environment variables from the app/forecast/rose-app.conf file into an [env] section in the app/forecast/opt/rose-app-test.conf file:





    • MAP_FILE



    • DOMAIN


    The rose-app-test.conf file should look like this:


    Run the application in “test mode” by providing the option --opt-conf-key=test to the rose app-run command:

    mkdir app/forecast/run
    cd app/forecast/run
    rose app-run --opt-conf-key=test -C ../
    cd ../../../

    You should see the stdout output of the Rose application. If there are any errors they will be marked with the [FAIL] prefix.

  2. Integrate the forecast application into the suite.

    We can now configure the forecast application to work with real data.

    We have moved the map template file (map-template.html) into the forecast application so we can delete the MAP_TEMPLATE environment variable from the [runtime]forecast section of the flow.cylc file.

    Copy the remaining environment variables defined in the forecast task within the flow.cylc file into the rose-app.conf file of the forecast application, replacing any values already specified if necessary. Remove the lines from the flow.cylc file when you are done.

    Remember, in Rose configuration files:

    • Spaces are not used around the equals (=) operator.

    • Ensure the environment variables are not quoted.

    The [env] section of your rose-app.conf file should now look like this:

    WIND_CYCLES=0, -3, -6

    Finally we need to change the forecast task to run rose task-run. The [runtime]forecast section of the flow.cylc file should now look like this:

        script = rose task-run
  3. Make changes to the configuration.

    Open the rose config-edit GUI and navigate to the suite conf > template variables panel.

    Change the RESOLUTION variable to 0.1

    Navigate to the forecast > env panel.

    Edit the WEIGHTING variable so that it is equal to the following list of values:

    0.7, 0.2, 0.1


    Click the “Add array element” button (+) to extend the number of elements assigned to WEIGHTING.

    Finally, save these settings via File > Save in the menu.

  4. Run the workflow.

    Validate, install, run and examine the workflow (use The Cylc GUI or The Cylc TUI):

    cylc validate ~/cylc-src/rose-suite-tutorial
    cylc install rose-suite-tutorial
    cylc play rose-suite-tutorial
  5. View output in Cylc Review.


    cylc review replaces the Rose Bush utility. It is a Cylc 7 command that can view Cylc 7 and Cylc 8 workflows.

    Either navigate to your site’s Cylc Review page if one has been set up, or start a Cylc Review server by running the following command and open the printed URL:

    cylc review start

    Navigate to your latest rose-suite-tutorial run and click the “task jobs list”. On this page you will see the tasks run by the suite, ordered from most to least recent. Near the top you should see an entry for the forecast task. On the right-hand side of the screen click job-map.html.

    As this file has a .html extension Cylc Review will render it. The raw text would be displayed otherwise.