[R-pkg-devel] download.file and https

[Paul Gilbert]

(This problem with download.file() affects quantmod, and possibly 
several other packages. e.g. getSymbols('M2',src='FRED') fails.)

I think the St Louis Fed has moved to using https for connections, and I 
believe all the US government web sites are doing this. An http request 
is automatically switched to https. The default download.file method 
does not seem to handle this, but method="wget" does:

 >  tmp <- tempfile()
 > 
download.file("http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv", 
destfile = tmp)
trying URL 
'http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv'
Error in 
download.file("http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv", 
  :
   cannot open URL 
'http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv'
 >
 >
 > 
download.file("http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv", 
destfile = tmp, method="wget")
--2015-07-02 22:29:49-- 
http://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv
Resolving research.stlouisfed.org (research.stlouisfed.org)... 65.89.18.120
Connecting to research.stlouisfed.org 
(research.stlouisfed.org)|65.89.18.120|:80... connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: 
https://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv 
[following]
--2015-07-02 22:29:49-- 
https://research.stlouisfed.org/fred2/series/M2/downloaddata/M2.csv
Connecting to research.stlouisfed.org 
(research.stlouisfed.org)|65.89.18.120|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [text/x-comma-separated-values]
Saving to: ‘/tmp/RtmpOX7kA1/file1ba639d7fd0f’

     [ <=>                                   ] 34,519       178KB/s   in 
0.2s

2015-07-02 22:29:50 (178 KB/s) - ‘/tmp/RtmpOX7kA1/file1ba639d7fd0f’ 
saved [34519]

Paul