blastula is an R package that can be used to send emails automatically. In addition, it can render Rmarkdown documents into emails, which can be sent later. The main challenge is to setup smtp server. In this post, I will show how to setup smtp server and send emails afterwards.

One can find more on blastula at github.

Install blastula

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install.packages("blastula")

Setup smtp server

Basically, one needs change settings in his email accounts to allow app-triggered actions, and this sometimes involves decreasing security levels, so may not be ideal. Here, I will describe settings for office365 and gmail smtp servers, and the credentials are based on App passwords, so it will not compromise email account securities overall.

office365 smtp server

Here I will use the email account ‘example@live.com’ as an example. And the steps are as follows:

1. enable 2-step verification by logging into the email account under security settings. One can follow this link for more details.

2. create app password. After enabling 2-step verification, one will see ‘App passwords’ under ‘Advanced security options’. Simply click ‘Create a new app password’ to get an app password. Record this password or keep the page open because we will use this password in next step. More details can be found at here.

3. store SMTP credentials in system’s key-value store.

   Run the following R code to store the credentials

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   create_smtp_creds_key( id = "my.office365", user = "example@live.com", host="smtp.office365.com", port=587, use_ssl = TRUE, overwrite=T )

   The above command will prompt to input password, just copy and paste the ‘app password’ from the prior step into the field, and click submit.

   Note that the ‘id’ argument provides a unique name for using the smtp server when sending emails (see next section).

   You may also use create_smtp_creds_file() to store credentials in a file, but it is not secure.

Gmail smtp server

Similar to office365 server setting, the setting for Gmail smtp server also includes the steps of enabling 2-step verification, generating app password, and storing the credentials.

Here, I use the gmail account ‘example@gmail.com’ as an example.

1. enable 2-step verification in gmail account. One can do so by visiting this page and under ‘Signing in to Google’. Follow instructions to finish it.

2. generate app password. After prior step, one can create app password by visiting google security page again. More details can be found here.

3. store smtp server credentials, using the following R code

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   create_smtp_creds_key( id = "my.gmail", user = "example@gmail.com", host="smtp.gmail.com", port=465, use_ssl = TRUE, overwrite=T )

   Here my.gmail is the id of the gmail server and can be called by using the function creds_key().

Prepare email

There are multiple ways to create emails. Here are a list of functions:

Here I will use compose_email to create an email object.

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header_text<-"This is an email header"

body_text<-"Hello,

This is body text.
"

footer_text<-"Footer is here"

email<-compose_email(body=body_text, header=header_text, footer=footer_text)

Send email

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# use office365 smtp server
email %>%
  smtp_send(
    to = "jesus@example.com",
    from = "example@live.com",
    subject = "An automatic email from office365 server",
    credentials = creds_key("my.office365")
  )

# or use gmail smtp server
email %>%
  smtp_send(
    to = "jesus@example.com",
    from = "example@gmail.com",
    subject = "An automatic email from gmail server",
    credentials = creds_key("my.gmail")
  )

Note that the email accounts from school or work may not allow settings like above, so the methods described here only work for accouts that allow one to change account security settings.

That is it. Happy R programming 😄.

References

1. blastula github page: https://github.com/rstudio/blastula

2. blastula vignette: https://cran.r-project.org/web/packages/blastula/vignettes/sending_using_smtp.html

Last modified on 2021-09-06