I am downloading a zip file from a site that uses basic authentication. The download seems to be going OK but when I try the unzip the file, it turns out to be empty. When I download the file by hand, it has several folders and files in it.
Here's what I am doing:
library(httr)
dest <- paste0(getwd(), "/data/weekly_2017-02-18.zip")
GET("https://www.example.com/weeklydata/weekly_2017-02-18.zip",
authenticate("myemail", "mypassword", "basic"),
write_disk(dest, overwrite = TRUE))
unzip(dest) # <-- THIS FAILS
What am I doing wrong?
unzip(dest)) <-- there is an extra closing bracket here
use:
unzipped <- unzip(dest)
Related
I wish to read into my environment a large CSV (~ 8Gb) but I am having issues.
My data is a publicly available dataset:
# CREATE A TEMP FILE TO STORE THE DOWNLOADED DATA
temp <- tempfile()
# DOWNLOAD THE FILE FROM THE CMS
download.file("https://download.cms.gov/nppes/NPPES_Data_Dissemination_February_2022.zip",
destfile = temp)
This is where I'm running into difficulty, I am unfamiliar with linux working directories and where temp folders are created.
When I use list.dir() or list.files() I don't see any reference to this temp file.
I am working in an R project and my working director is as follows:
getwd()
[1] "/home/myName/myProjectName"
I'm able to read in the first part of the file but my system crashes after about 4Gb.
# UNZIP THE NPI FILE
npi <- unz(temp, "npidata_pfile_20050523-20220213.csv")
I then came across this post which has a function for decompressing large zip files using the system2 unzip functionality. However due to my limited R knowledge and Linux experience I couldn't get the function to point to the downloaded file in the temp folder
checking the path for temp above I get the following path:
temp
[1] "/tmp/Rtmpl6SHIJ/file7e5e6c1fc693"
Using the system2 function from the link above I tried the following:
x <- decompress_file(directory = temp,
file = "NPPES_Data_Dissemination_February_2022.zip")
But get the following error about setting the working directory:
Any pointers to how I can get this file unzipped given it's size and read it into memory would be much appreciated.
It might be a file permission issue. To get around it work in a directory you're already in, or know you have access to.
# DOWNLOAD THE FILE
# to a directory you can access, and name the file. No need to overcomplicate this.
download.file("https://download.cms.gov/nppes/NPPES_Data_Dissemination_February_2022.zip",
destfile = "/home/myName/myProjectname/npi.csv")
# use the decompress function if you need to, though unzip might work
x <- decompress_file(directory = "/home/myName/myProjectname/",
file = "npi.zip")
# remove .zip file if you need the space back
file.remove("/home/myName/myProjectname/npi.zip")
temp is the path to the file, not just the directory. By default, tempfile does not add a file extension. It can be done by using tempfile(fileext = ".zip")
Consequently, decompress_file can not set the working directory to a file. Try this:
x <- decompress_file(directory = dirname(temp), file = basename(temp))
I'm hosting my first shiny app from www.shinyapps.io. My r script uses a glm I created locally that I have stored as a .RDS file.
How can I read this file into my application directly using a free file host such as dropbox or google drive? (or another better alternative?)
test<-readRDS(gzcon(url("https://www.dropbox.com/s/p3bk57sqvlra1ze/strModel.RDS?dl=0")))
however, I get the error:
Error in readRDS(gzcon(url("https://www.dropbox.com/s/p3bk57sqvlra1ze/strModel.RDS?dl=0"))) :
unknown input format
I assume this is because the URL doesn't lead directly to the file but rather a landing page for dropbox?
That being said, I can't seem to find any free file hosting sites that have that functionality.
As always, I'm sure the solution is very obvious, any help is appreciated.
I figured it out. Hosted the file in a GitHub repository. From there I was able to copy the link to the raw file and placed that link in the readRDS(gzcon(url())) wrappers.
Remotely reading using readRDS() can be disappointing. You might want to try this wrapper that saves the data set to a temporary location before reading it locally:
readRDS_remote <- function(file, quiet = TRUE) {
if (grepl("^http", file, ignore.case = TRUE)) {
# temp location
file_local <- file.path(tempdir(), basename(file))
# download the data set
download.file(file, file_local, quiet = quiet, mode = "wb")
file <- file_local
}
readRDS(file)
}
I am trying to save a zip file from the internet onto my computer. I can download the content straight into R with:
sfile <- "http://xweb.geos.ed.ac.uk/~smaccal1/ARCLake/v3_0/PL/ALID0001.zip"
temp <- tempfile()
download.file(sfile,temp)
From here, how can I then save that zipped file on my computer without having to open it in R by unzipping the folder and then using read.table
data <- read.table(unz(temp, "a1.dat"))
unlink(temp)
and then save that data. Essentially I would like to save the files directly from the web (still zipped). How can this be done?
You can use download.file to save the file in a specified location:
sfile <- "http://xweb.geos.ed.ac.uk/~smaccal1/ARCLake/v3_0/PL/ALID0001.zip"
download.file(sfile, destfile = "/path/to/myfile.zip")
I'm trying to download and extract a zip file using R. Whenever I do so I get the error message
Error in unzip(temp, list = TRUE) : 'exdir' does not exist
I'm using code based on the Stack Overflow question Using R to download zipped data file, extract, and import data
To give a simplified example:
# Create a temporary file
temp <- tempfile()
# Download ZIP archive into temporary file
download.file("http://cran.r-project.org/bin/windows/contrib/r-release/ggmap_2.2.zip",temp)
# ZIP is downloaded successfully:
# trying URL 'http://cran.r-project.org/bin/windows/contrib/r-release/ggmap_2.2.zip'
# Content type 'application/zip' length 4533970 bytes (4.3 Mb)
# opened URL
# downloaded 4.3 Mb
# Try to do something with the downloaded file
unzip(temp,list=TRUE)
# Error in unzip(temp, list = TRUE) : 'exdir' does not exist
What I've tried so far:
Accessing the temp file manually and unzipping it with 7zip: Can do this no problem, file is there and accessible.
Changing the temp directory to c:\temp. Again, the file is downloaded successfully, I can access it and unzip it with 7zip but R throws the exdir error message when it tries to access it.
R version 2.15.2
R-Studio version 0.97.306
Edit: The code works if I use unz instead of unzip but I haven't been able to figure out why one works and the other doesn't. From CRAN guidance:
unz reads (only) single files within zip files...
unzip extracts files from or list a zip archive
On a windows setup:
I had this error when I had exdir specified as a path. For me the solution was removing the trailing / or \\ in the path name.
Here's an example and it did create the new folder if it didn't already exist
locFile <- pathOfMyZipFile
outPath <- "Y:/Folders/MyFolder"
# OR
outPath <- "Y:\\Folders\\MyFolder"
unzip(locFile, exdir=outPath)
This can manifest another way, and the documentation doesn't make clear the cause. Your exdir cannot end in a "/", it must be just the name of the target folder.
For example, this was failing with 'exdir' does not exist:
unzip(temp, overwrite = F, exdir = "data_raw/system-data/")
And this worked fine:
unzip(temp, overwrite = F, exdir = "data_raw/system-data")
Presumably when unzip sees the "/" at the end of the exdir path it keeps looking; whereas omitting the "/" tells unzip "you've found it, unzip here".
A couple of years late but I still get this error when trying to use unzip(). It appears to be a bug because the man pages for unzip state if exdir is specified it will be created:
exdir The directory to extract files to (the equivalent of unzip -d).
It will be created if necessary.
A workaround I've been using is to manually create the necessary directory:
dir.create("directory")
unzip("file-to-unzip.zip", exdir = "directory/")
A pain, but it seems to work, at least for me.
I am using R3.2.1 on a Windows 7 machine.
The way I found to address this issue takes a few steps, but it works for me:
Create a vector that contains the name of the url from where you are downloading the file, e.g.
file_url <- "http://your.file.com/file_name.zip"
Use download.file to specify the url where you are downloading the file from (using your newly created vector), followed by the file name of the zipped file (that should be the last part of the url name). It will be saved as such in your working directory*, e.g.
download.file(file_url, "file_name.zip")
*If you are not sure of your working directory, you can use getwd() to check it. If you want to change your working directory, you can use setwd("C:users/username/...") to set it to what you want.
Use "unzip" to unzip the file into your working directory, with the name you will set using exdir, e.g.
unzip("file_name.zip", exdir = "file_name")
To check your work, you can use list.files, e.g.
list.files("file_name")
Hope this helps!
I would like to download a file directly into my working directory
I can do this to a temp directory:
download.file("http://www.abc.com/abc.zip",temp)
but what do I have to replace temp with to get it to download to the working directory?
If your url is in a variable, you can use basename to get the "filename" part out of it:
u <- "http://www.abc.com/abc.zip"
basename(u) # "abc.zip"
# downloads to current directory:
download.file(u, basename(u))
# downloads to subdirectory "foo":
download.file(u, file.path("foo", basename(u)))
The second argument of download.file() is destfile and it must be specified. I don't have a Windows machine to test this on, but both of these work on my linux box and I can't see why at least the second won't work on Windows too:
download.file("http://www.abc.com/abc.zip", "./abc.zip")
download.file("http://www.abc.com/abc.zip", "abc.zip")
The second of those indicates that if you just give a filename, the file will be download to the current working directory and saved under the stated name.