One Little Thing: knitr::imgur_upload()

Yihui Xie 2017-09-15

Earlier this year, Nick Tierney wrote a blog post titled “Magic reprex”. I strongly recommend to you to read it. The credit mostly goes to Jenny Bryan (for the excellent reprex package), but I think this post is worth reading because it shares the joy of discovering little things, which is extremely valuable in my eyes.

Nick mentioned the function knitr::imgur_upload(), and this is one of the many little functions that I feel proud of in my packages. I love these little functions because they were relatively simple for me to write (at least the source code is usually very short), but can be surprisingly useful. This function can be used to upload an image file to, and it returns the URL of the image.

Jenny discovered this function and made good use of it: when you prepare a reproducible example (reprex), your plots in the example will be automatically uploaded, which makes it really hassle-free to prepare a reprex.

After Jenny finished the reprex package, she discovered my formatR::tidy_eval() function, which actually used the similar idea as reprex. I wrote it a few years ago but just like other little functions, I rarely actively promote them, so unless you read the documentation very carefully, you probably won’t notice them. I plan to write more posts in the “One Little Thing” series in the future.

P.S. I wrote the imgur_upload() function in early 2012 (a few days after knitr was first released to CRAN), when my only choices was the packages RCurl and XML. If I were to write it today, I’d probably use httr or curl and xml2 instead. If you want to rewrite it using these “modern” packages, please feel free to submit a pull request on GitHub. Christophe Dervieux has done it. Thank you!