transferring dataframes including column specifications

[PietrH]

Currently the workflow for transferring data between etnservice and etn-client is as follows:

graph LR;
   etnservice --> rob[R Object]
   rob --> JSON
   JSON --> rob2[parsed JSON R Object]

etnservice produces an R object, that is converted into JSON by the opencpu request (/json suffix in the url), and then parsed back into an R object by etn-client.

However, in this translation certain information gets lost, in this case the column specification. Which means that etn-client has no way of knowing what class the different columns are in tabular data for example.

Implementing column parsing on the client side is prone to errors, because the client doesn't have database access.

[PietrH]

We are now using the two step transfer method of using OpenCPU

sequenceDiagram

client ->> OpenCPU: POST function + arguments
activate OpenCPU
OpenCPU -->> client: list of object paths
client ->> OpenCPU: GET rda path
OpenCPU -->> client: response rda object
deactivate OpenCPU