Causal Chain

Generating Workflows

Automation and management tasks are usually characterized by a sequence of actions. In practice, it makes little sense to initiate only one action and launch a subsequent one based on it at a later time. To bundle different tasks, StackStorm uses workflows that assign actions to a higher level of automation and coordinate their execution by running the right action at the right time with the right input. Information can be passed into and processed in such an execution thread. Like actions, you manage workflows in the automation library and fall back on the configurations stored there, if necessary. In principle, a workflow can even be made up of other workflows.

StackStorm supports two workflow variants: ActionChain and Orquesta. ActionChain is the older variant that uses simple syntax to define a chain of actions. The disadvantage of this variant is that complex workflows are not possible. Orquesta is a new workflow engine that recognizes sequential workflows or complex workflows with forks, links, and sophisticated data transformations and queries. The developers advise that you use Orquesta.

StackStorm provides various tools for creating workflows. In the open source variant, you have to make use of console-based development. The commercial StackStorm variant is known as Extreme Workflow Composer [4] (Figure 3), which has an integrated visual editor you can use to design actions and their sequence in a drag-and-drop process.

Figure 3: The commercial StackStorm variant Extreme Workflow Composer provides a visual editor that simplifies the configuration and management of workflows.

StackStorm is under active development and will see further continuous development. The roadmap [5] summarizes planned innovations. However, advance announcements at press time did not go beyond those of the current version 3.3.0.

Conclusions

StackStorm is pursuing a highly interesting approach that significantly simplifies the automation of complex IT infrastructures. The limitation to events and service states could prove to be a disadvantage. Approaches that can act in event-dependent and -independent ways might be a better solution.