Implementation

Dependencies

Class hierarchy

Command

An action that causes changes only internal to the CLI.

Operation

An action that causes one or more reads or writes against a DataONE Node.

main:

• Handle command line options.

• Capture and display internal and external exceptions.

CLI:

• Generic boiler plate for Python CLI apps.

• Simple command tokenizing and validation.

CommandProcessor:

• Manipulate the session.

• Create, then execute DataONE Read Operations.

• Create, then queue DataONE Write Operations.

• Execute queue of DataONE Write Operations.

• Display the results of DataONE Operations.

OperationMaker:

• Combine parameters from CommandProcessor and from the session into a DataONE Read or Write Operation.

OperationQueue:

• Hold a queue of DataONE Write Operations.

• Edit the queue.

• Display the queue.

OperationExecuter:

• Execute a DataONE Read Operation or a queue of Write Operations.

Utility classes

These are used throughout the main classes and so are kept out of main hierarchy for readability.

Notes

• Read operations are executed immediately.

• Write operations are queued and executed in a batch. The write queue can be edited.

• Write operations are decoupled from the session. Each write operation contains a copy of the relevant session variables at the time the operation was issued. Those variables are then used when the operation is executed.