drive_read()?

[tiernanmartin]

Is there a way to read a data object out of a dribble (similar to readr::read() or googlesheets::gs_read())?

[jennybc]

Not yet but it could happen. Question is: what sort of object do you read it into? Sheets are one thing and will be handled by googlesheets. But what else might you want to read straight into an R object? 🤔 Curious to hear the use you have in mind.

[tiernanmartin]

While I do use Google Drive to create and edit spreadsheets, I also use it as cloud-based data storage for file formats that aren't editable through the Drive interface. These file formats include .csv, .md, .rds, .zip, .gpkg, etc.

So I guess I'd like a function that could serve a wrapper around the read_* functions, giving them access to my Drive account.

Something like:

## this code is for illustration purpose - not a functional reprex

# Upload file to Drive
write.csv(chickwts, "chickwts.csv")
drive_chickwts <- drive_upload("chickwts.csv")

# Read that file back into R
drive_read(obj = drive_chickwts , fun = read_csv, fun_args = list()) # fun_args would be passed to the read function's params

[jennybc]

It's been a while but if you still care about this @tiernanmartin, I'd love to hear if it meets your needs.

See #363. There are tons of examples, which I may have to move to an article, because they involve packages that googledrive has no formal relationship with.

[tiernanmartin]

Nice! This looks great.

I am not sure whether it will meet my particular needs. I work with a lot of geopackage (.gpkg) files that I store on google drive, and my naïve attempt to access one of those with this new function returned an error.

Here's a reprex:

library(tidyverse)
library(sf)
library(googledrive)

nc <- st_read(system.file("shape/nc.shp", package="sf"))

st_write(nc, "nc.gpkg")

nc_in_drive <- drive_upload("nc.gpkg")

drive_read(nc_in_drive) %>% 
  st_read()

## Error in CPL_read_ogr(dsn, layer, query, as.character(options), quiet,  : 
## Expecting a single value: [extent=167936].
## In addition: Warning message:
## In if (nchar(dsn) < 1) { :
## the condition has length > 1 and only the first element will be used

[jennybc]

I'm looking at the docs for sf::st_read():

https://r-spatial.github.io/sf/reference/st_read.html

The first argument dsn is documented as:

data source name (interpretation varies by driver - for some drivers, dsn is a file name, but may also be a folder, or contain the name and access credentials of a database); in case of GeoJSON, dsn may be the character string holding the geojson data. It can also be an open database connection.

It does not surprise me that piping the result of drive_read() directly into this does not work.

For this to "just work", you need to see that the primary input can be a raw vector, which is presumably what you're getting from drive_read() here. (If you re-install from #363, you should get some messaging around how as is being set.)

It is possible that by explicitly requesting as = "string" you might have success, if this branch is relevant to your usage: "in case of GeoJSON, dsn may be the character string holding the geojson data".

drive_read() can only provide ready-to-use input for functions that are already prepared to handle raw or string input. Otherwise, you really do just need to download a file and feed it to the next function.

[jennybc]

A great example of the type of function that drive_read() can pipe right into is readr::read_csv(). Its primary input file is documented like so (bold is mine)

Either a path to a file, a connection, or literal data (either a single string or a raw vector).

[jennybc]

Note that textConnection() can potentially be inserted as an adapter between string output from drive_read() and a function that accepts a connection.

[tiernanmartin]

Thanks for these suggestions, Jenny.

I played around with a couple combinations of file types but I didn't come across any that worked. I am ok with that. Your documentation is very clear about what types of files are supported, so I was not really expecting it to "just work" with something exotic like a geopackage. I appreciate you taking the time to brainstorm some possible approaches--and who knows maybe someone else will chime in with a solution at some point.

Thanks for bringing drive_read() to life.

Issue closed! +1

[jennybc]

I’m going to reopen and let the PR merge close this. We might use this issue as a demo re: PR review in an upcoming group meeting.