canvas-grades

#!/usr/bin/env ruby
# frozen_string_literal: true

# canvas-grades.rb
# Author: William Woodruff
# ------------------------
# Get a student's current term grades from Canvas.
# Tested on UMD ELMS. Requires an access token (/profile/settings).
# ------------------------
# This code is licensed by William Woodruff under the MIT License.
# http://opensource.org/licenses/MIT

require "json"
require "open-uri"

SEASON_MAPPING = {
  "Winter" => 0,
  "Spring" => 1,
  "Summer" => 2,
  "Fall" => 3,
}.freeze

def current_term(courses)
  terms = courses.map { |c| c["term"]["name"].split(" ") }
  year_terms = terms.select { |t| t[1].to_i == Time.now.year }.uniq

  current_term = year_terms.first
  year_terms.each do |term|
    if SEASON_MAPPING[term.first] > SEASON_MAPPING[current_term.first]
      current_term = term
    end
  end

  current_term.join(" ")
end

KEY = ENV["CANVAS_API_KEY"]
URL = "https://myelms.umd.edu/api/v1/courses?" \
  "enrollment_type=student" \
  "&state=available" \
  "&include[]=total_scores&include[]=term" \
  "&access_token=%<key>s"

abort("#{$PROGRAM_NAME}: Missing environment: CANVAS_API_KEY.") unless KEY

url = URL % { key: KEY }

begin
  response = JSON.parse(open(url).read)
rescue OpenURI::HTTPError => e
  abort "Fatal: #{e}"
end

current_courses = response.select do |course|
  course["term"]["name"] == current_term(response)
end

current_courses.each do |course|
  name = course["course_code"]
  grade = course["enrollments"].first["computed_current_score"]

  puts "#{name}: #{grade}"
end