Embedding images in an e-mail with Microsoft365R

I'm trying to send an email with the Microsoft365R package. There's an embedded image I need in it. I've tried two ways:

library(Microsoft365R)

emails <- c("[email protected]")

for(i in emails){
my_outlook <- get_business_outlook()
my_email <- my_outlook$create_email()$
  set_body("<img src=`https://raw.githubusercontent.com/iagocnunes/test/main/002.png` alt=`image`>", content_type="html")$
  set_subject("Test")$
  set_recipients(to = i)$
  send()
}

And:

for(i in emails){
  my_outlook <- get_business_outlook()
  my_email <- my_outlook$create_email()$
    set_body("<b>test testing", content_type="html")$
    add_image("https://raw.githubusercontent.com/iagocnunes/test/main/002.png")$
    set_subject("Test")$
    set_recipients(to = i)$
    send()
}

In both the image fails to embed. Why is this happening and how can I get it right?

Solution

A few things could cause an image not to render as expected.

In this case, the backtick characters should be replaced with ' single quotes and it should work. E.g. this should work

library(Microsoft365R)

emails <- c("[email protected]")

for(i in emails){
my_outlook <- get_business_outlook()
my_email <- my_outlook$create_email()$
  set_body("<img src='https://raw.githubusercontent.com/iagocnunes/test/main/002.png' alt='image'>", content_type="html")$
  set_subject("Test")$
  set_recipients(to = i)$
  send()
}

A second thing that can cause images not to render as expected is if the image's mimetype isn't what it appears to be. Basically, we could reasonably assume that if a file has the extension .png, that its mimetype is also png. However, sometimes someone will have an unsupported image type, they'll rename it (giving it a different extension), but it won't change it's mimetype and so it won't render (this happened to me once with the webp file type). I checked your image's mimetype here and confirm it's mimetype is image/png, which is a supported type.

One last thing that could cause an image not to render (you already have this) is if the content_type="html" argument is missing in set_body() (see microsoft365R manual):

The object argument should be a filename, and the message content type will be set to "html"