Figure 8.7 illustrates the different stages in the lifecycle of a workflow.
Locking and unlocking parameters
Figure 8.7: The life cycle of a workflow.
The first stage, workflow creation, was explained in Creating a workflow. The next stage, the installation of a workflow on a Workbench or Server is explained in Distributing and installing workflows). The final stage is the executation of the workflow via the Toolbox, just like other tools.
During the creation step, the workflow author can specify which parameters should be locked or unlocked. If a parameter is locked, it cannot be changed in the installation or the execution step. Conversely, if it is left open, that parameter can be changed, either when running the Workflow or when installing it. See Distributing and installing workflows). The lock icons shown in figure 8.4 specify whether the parameter is left open or whether it is locked.
By default, data parameters are unlocked. When installing the workflow on a different system to the one where it was created, the connection to the data needs to be re-established. This is only possible when the parameter is unlocked. Data parameters should only be locked if they should not be set, or if the workflow will only be installed in a setting where there is access to the same data in the same location as the system where the Workflow was created.