Prepare Progress Reports to Email with R, Canvas, and rcanvas

While neglecting my Python coursework this fall, I wrote an rstats package called rcanvas. rcanvas is an R client for the Canvas LMS API. It makes getting course data from your institution’s Canvas LMS easy, and I’ve utilized it in a variety of ways at work. And despite the Canvas Developer community’s tepid response, I am optimistic about its future. Perhaps a quick demonstration will help.

In this post, I will show how to prepare progress updates with R. This post only addresses getting the necessary data from Canvas, because Jenny Bryan already has a fantastic tutorial on sending the emails. Note: before reading on, make sure your CANVAS_API_TOKEN is an environment variable in your .Renviron.

First, we load the required packages:

library(rcanvas)
library(tidyverse) #wow, this line really is a thing a beauty

Next, we’ll obtain the course ids for the courses to which we wish to send updates. At work I would chain a filter() clause to get_course_list() to specify the precise courses, but that would be unique to me.

courses <- get_course_list()

courses is a data.frame with a variety of course information. To get each student’s current grade and email, we’ll have to make two separate calls to get_course_items() within a custom function before iterating through a vector of course ids.

get_grades_and_emails <- function(id) {
    grades <- get_course_items(id, "enrollments") %>%
        filter(role == "StudentEnrollment") %>%
        select(user.sis_user_id, user.name, grades.current_score, course_id)
    emails <- get_course_items(id, "users", include = "email") %>%
        select(sis_user_id, email)
    left_join(grades, emails, by = c("user.sis_user_id" = "sis_user_id")
}

safe_function <- possibly(get_grades_and_emails, NULL) #avoids error failing

student_data <- courses$id %>%
    map(safe_function) %>%
    bind_rows() %>%
    left_join(courses %>% select(id, course_code), #here we join the course name onto the data.frame
              by = c("course_id" = "id"))

student_data now contains all the necessary data: each student’s name, grade, email, and course name (or code). With sprintf(), you can construct a prose message that ties each of these elements in as stern or celebratory fashion as you wish.

More rcanvas functionality is forthcoming.