In ProvTools/provDebugR: A Time-Travelling Debugger

Installation

Version 3.5.0 or later of R is required.

devtools is needed for installation:

install.packages("devtools")

Installation of all required packages (can be copied and pasted):

install.packages("provParseR")
install.packages("provGraphR")
install.packages("rdtLite")
devtools::install_github("End-to-end-provenance/provDebugR")

provDebugR also imports: httr igraph jsonlite methods testthat textutils

Initialisation

provDebugR must be initialised using one of the following functions before the rest of its suite of functions becomes available. prov.debug.run prov.debug * prov.debug.file

`prov.debug.run(script, ...)`

prov.debug.run takes in the path to an R or Rmd script and executes the script using rdtLite to collect provenance before initialising the debugger.

library(provDebugR)
prov.debug.run("myScript.R", snapshot.size = 100)

`prov.debug()`

Alternatively, if rdtLite's prov.run function was just called, the provenence stored in memory can be used directly to initialise the debugger.

library(rdtLite)
library(provDebugR)
prov.run("myScript.R", snapshot.size = 100)
prov.debug()

`prov.debug.file`

Lastly, the debugger may also be initialised using a PROV-JSON provenance file.

library(rdtLite)
prov.debug.file("provJsonFileName.json")

Other provDebugR Functions

After the debugger has been initialised, the rest of provDebugR's suite of functions may be used.

`debug.error`

This functions returns the backwards lineage of (steps leading up to) the error, if any. The error may then be searched for on Stack Overflow.

`debug.line`

This function enables the user to see what the queried line(s) immediate inputs and outputs are, if any.

`debug.lineage`

This function returns the forwards or backwards lineage of the data object(s) queried. The forwards lineage shows how the data object was used, and the backwards lineage shows how it was produced.

`debug.state`

This function returns the state at the line(s) queried, after the line had been executed. The state is the list of all variables and their values in the environment at the queried line.