Error(s) in re-building vignettes:
  ...
--- re-building ‘correlation-utils.Rmd’ using rmarkdown
--- finished re-building ‘correlation-utils.Rmd’

--- re-building ‘covidcast.Rmd’ using rmarkdown

Quitting from lines 38-45 [unnamed-chunk-1] (covidcast.Rmd)
Error: processing vignette 'covidcast.Rmd' failed with diagnostics:
Internal Server Error (HTTP 500). Failed to fetch data from API anonymously.
--- failed re-building ‘covidcast.Rmd’

--- re-building ‘external-data.Rmd’ using rmarkdown
** Processing: /home/hornik/tmp/R.check/r-devel-clang/Work/PKGS/covidcast.Rcheck/vign_test/covidcast/vignettes/external-data_files/figure-html/unnamed-chunk-3-1.png
288x288 pixels, 3x8 bits/pixel, RGB
Input IDAT size = 20618 bytes
Input file size = 20720 bytes

Trying:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 17871
  zc = 9  zm = 8  zs = 1  f = 0
  zc = 1  zm = 8  zs = 2  f = 0
  zc = 9  zm = 8  zs = 3  f = 0
  zc = 9  zm = 8  zs = 0  f = 5
  zc = 9  zm = 8  zs = 1  f = 5
  zc = 1  zm = 8  zs = 2  f = 5
  zc = 9  zm = 8  zs = 3  f = 5
                               
Selecting parameters:
  zc = 9  zm = 8  zs = 0  f = 0		IDAT size = 17871

Output IDAT size = 17871 bytes (2747 bytes decrease)
Output file size = 17949 bytes (2771 bytes = 13.37% decrease)


Quitting from lines 94-100 [unnamed-chunk-4] (external-data.Rmd)
Error: processing vignette 'external-data.Rmd' failed with diagnostics:
Internal Server Error (HTTP 500). Failed to fetch data from API anonymously.
--- failed re-building ‘external-data.Rmd’

--- re-building ‘multi-signals.Rmd’ using rmarkdown
--- finished re-building ‘multi-signals.Rmd’

--- re-building ‘plotting-signals.Rmd’ using rmarkdown

Quitting from lines 24-35 [unnamed-chunk-1] (plotting-signals.Rmd)
Error: processing vignette 'plotting-signals.Rmd' failed with diagnostics:
Internal Server Error (HTTP 500). Failed to fetch data from API anonymously.
--- failed re-building ‘plotting-signals.Rmd’

SUMMARY: processing the following files failed:
  ‘covidcast.Rmd’ ‘external-data.Rmd’ ‘plotting-signals.Rmd’

Error: Vignette re-building failed.
Execution halted