Data Item Dependencies

Both pre-process and in-process dependencies can be defined using the names of the data items defined in the project that the Agent is running. The Agent evaluates Data Item dependencies, both pre-process and in-process. For the pre-process dependencies, the Agent executes the package only if the evaluation of the data item comparison is true (if data_item_name < 3", for example). For in-process dependencies, the Agent waits for a specified length of time until the data item comparisons are true before executing the instructions that follow the dependencies. When the specified length of time is reached and the condition is still not true, the Agent sends an error code to the Axeda Platform.

For in-process dependencies defined using the Wait for Condition instruction, the agents wait for a specified length of time until the data item comparisons are true before it executes the instructions that follow the dependencies. When the specified length of time is reached and the condition is still not true, the Agent sends an error code to the Axeda Platform. To see the error text, select View | Package Deployments, select the package whose status is Error, and in the Assets tab, locate the asset, and read the error text in the Status column for the asset.

The Data Item and custom dependencies are grouped together for in-process dependencies. Each dependency must be true before the subsequent instructions are run (that is, they are AND'd together). The set of in-process dependencies has a timeout; if exceeded, the dependency is false, and the instruction set fails.

Note: Data items can be configured such that the Axeda Platform does NOT store them. Even though they are not stored, these data items are still visible in the Package wizard because the Axeda Gateway or Axeda Connector Agent runs the package and has all the data items, even if the Platform does not store them.