WorkflowService doesn't work with nodesEdges, edges, or any other top level entry

[kinow]

The current implementation of the WorkflowService is tailored for a GraphQL such as

{
  data: {
    workflow: {...},
    nodesEdges: {...},
    tasks: {....}
  }
}

The Vuex store has the methods to store the data.workflow object. And the service discards any other top level entry such as nodesEdges, tasks, etc. Picking only workflow.

But while reviewing cylc/cylc-flow#3337 & cylc/cylc-uiserver#70, and experimenting with Cylc UI to confirm nothing was broken, I noticed that the WorkflowService never populated the Vuex store.

We can work around it with GraphQL aliases, but it only works until another query is registered that overrides it by requesting workflows {}.

Maybe the WorkflowService would have to be renamed to GraphQLService, or simply refactored to store the data in the Vuex store, without picking any of its attributes.

[dwsutherland]

Both tasks and nodesEdges can be sub fields of workflows ... but this seems kinda restrictive (as each query will be binned into the workflows by force)... I would vote to use data