12. Get started with Nextflow Tower¶
12.1 Basic concepts¶
Nextflow Tower is the centralized command post for data management and workflows. It brings monitoring, logging and observability to distributed workflows and simplifies the deployment of workflows on any cloud, cluster or laptop. In Tower terminology, a workflow is what we've been working on so far, and pipelines are pre-configured workflows that can be used by all users in a workspace. It is composed of a workflow repository, launch parameters, and a compute environment. We'll stick to these definitions in this section.
Nextflow tower core features include:
- The launching of pre-configured pipelines with ease.
- Programmatic integration to meet the needs of an organization.
- Publishing pipelines to shared workspaces.
- Management of the infrastructure required to run data analysis at scale.
You can use Tower via either the
-with-tower option while using the
nextflow run command, through the online GUI or through the API.
12.2.1 Via the
nextflow run command¶
Create an account and login into Tower.
1. Create a new token
You can access your tokens from the Settings drop-down menu:
2. Name your token
3. Save your token safely
Copy and keep your new token in a safe place.
4. Export your token
Once your token has been created, open a terminal and type:
eyxxxxxxxxxxxxxxxQ1ZTE= is the token you have just created.
nextflow -version. Bearer tokens require Nextflow version 20.10.0 or later and can be set with the second command shown above. You can change the version if necessary.
To submit a pipeline to a Workspace using the Nextflow command-line tool, add the workspace ID to your environment. For example:
The workspace ID can be found on the organization’s Workspaces overview page.
5. Run Nextflow with tower
Run your Nextflow workflows as usual with the addition of the
You will see and be able to monitor your Nextflow jobs in Tower.
To configure and execute Nextflow jobs in Cloud environments, visit the Compute environments section.
Run the RNA-Seq
script7.nf using the
-with-tower flag, after correctly completing the token settings outlined above.
Go to https://tower.nf/, login, then click the run tab, and select the run that you just submitted. If you can’t find it, double check your token was entered correctly.
12.2.2 Via online GUI¶
To run using the GUI, there are three main steps:
- Create an account and login into Tower, available free of charge, at tower.nf.
- Create and configure a new compute environment.
- Start launching pipelines.
184.108.40.206 Configuring your compute environment¶
Tower uses the concept of Compute Environments to define the execution platform where a workflow will run.
It supports the launching of workflows into a growing number of cloud and on-premise infrastructures.
Each compute environment must be pre-configured to enable Tower to submit tasks. You can read more on how to set up each environment using the links below.
The following guides describe how to configure each of these compute environments.
220.127.116.11 Selecting a default compute environment¶
If you have more than one Compute Environment, you can select which one will be used by default when launching a pipeline.
- Navigate to your compute environments.
- Choose your default environment by selecting the Make primary button.
You are now ready to launch workflows with your primary compute environment.
Launchpad makes it easy for any workspace user to launch a pre-configured pipeline.
A pipeline is a repository containing a Nextflow workflow, a compute environment and workflow parameters.
18.104.22.168 Pipeline Parameters Form¶
Launchpad automatically detects the presence of a
nextflow_schema.json in the root of the repository and dynamically creates a form where users can easily update the parameters.
The parameter forms view will appear if the pipeline has a Nextflow schema file for the parameters. Please refer to the Nextflow Schema guide to learn more about the schema file use-cases and how to create them.
This makes it trivial for users without any expertise in Nextflow to enter their workflow parameters and launch.
22.214.171.124 Adding a new pipeline¶
Adding a pipeline to the pre-saved workspace launchpad is detailed in full on the tower webpage docs.
In brief, these are the steps you need to follow to set up a pipeline.
- Select the Launchpad button in the navigation bar. This will open the Launch Form.
- Select a compute environment.
- Enter the repository of the workflow you want to launch. e.g. https://github.com/nf-core/rnaseq.git
- Select a workflow Revision number. The Git default branch (main/master) or
manifest.defaultBranchin the Nextflow configuration will be used by default.
- Set the Work directory location of the Nextflow work directory. The location associated with the compute environment will be selected by default.
- Enter the name(s) of each of the Nextflow Config profiles followed by the
Enterkey. See the Nextflow Config profiles documentation for more details.
Enter any workflow parameters in YAML or JSON format. YAML example:
Select Launch to begin the pipeline execution.
Nextflow workflows are simply Git repositories and can be changed to any public or private Git-hosting platform. See Git Integration in the Tower docs and Pipeline Sharing in the Nextflow docs for more details.
The credentials associated with the compute environment must be able to access the work directory.
In the configuration, the full path to a bucket must be specified with single quotes around strings and no quotes around booleans or numbers.
For advanced settings options check out this page.
There is also community support available if you get into trouble, join the Nextflow Slack by following this link.
To learn more about using the Tower API, visit the API section in this documentation.
12.3 Workspaces and Organizations¶
Nextflow Tower simplifies the development and execution of pipeline by providing a centralized interface for users and organizations.
Each user has a unique workspace where they can interact and manage all resources such as workflows, compute environments and credentials. Details of this can be found here.
Organisations can have multiple workspaces with customized access for specific organisation members and collaborators.
12.3.1 Organization resources¶
You can create your own organization and participant workspace by following the docs at tower.
Tower allows the creation of multiple organizations, each of which can contain multiple workspaces with shared users and resources. This allows any organization to customize and organize the usage of resources while maintaining an access control layer for users associated with a workspace.
12.3.2 Organization users¶
Any user can be added or removed from a particular organization or a workspace and can be allocated a specific access role within that workspace.
The Teams feature provides a way for organizations to group various users and participants together into teams. For example,
analysts, and apply access control to all the users within this team collectively.
For further information, please refer to the User Management section.
126.96.36.199 Setting up a new organization¶
Organizations are the top-level structure and contain Workspaces, Members, Teams and Collaborators.
To create a new Organization:
- Click on the dropdown next to your name and select New organization to open the creation dialog.
On the dialog, fill in the fields as per your organization. The Name and Full name fields are compulsory.
A valid name for the organization must follow a specific pattern. Please refer to the UI for further instructions.
The rest of the fields such as Description, Location, Website URL and Logo Url are optional.
Once the details are filled in, you can access the newly created organization using the organization’s page, which lists all of your organizations.
It is possible to change the values of the optional fields either using the Edit option on the organization’s page or by using the Settings tab within the organization page, provided that you are the Owner of the organization.
A list of all the included Members, Teams and Collaborators can be found on the organization page.