speedtest2slack.sh

#!/usr/bin/env bash

set -euo pipefail

run_speedtest() {
  speedtest -f json
}

to_slack_message() {
  jq -c --argjson threshold "$1" '
    if .type == "result" then . else halt end | {
      ping: (.ping.latency + 0.5) | floor,
      download: (.download.bandwidth / 125000) | floor,
      upload: (.upload.bandwidth / 125000) | floor,
      server: .server,
      url: .result.url
    } | {
      text: [
        if .download < $threshold then
          "<!channel> :rotating_light: *Slow connection*"
        else
          empty
        end,
        "*Ping* \(.ping) ms *↓* \(.download) Mbps *↑* \(.upload) Mbps",
        "*Server* \(.server.name) - \(.server.location)",
        .url
      ] | join("\n")
    }
  '
}

send_message() {
  curl \
    -fsSL \
    -X POST \
    -H 'Content-Type: application/json' \
    -d "$1" \
    "$SLACK_WEBHOOK_URL"
}

check_args() {
  if [[ "${1:-}" =~ [^0-9] ]]; then
    echo "Error: The threshold must be a positive integer." >&2
    exit 1
  elif [[ ! "${SLACK_WEBHOOK_URL:-}" =~ ^https?:// ]]; then
    echo "Error: The environment variable SLACK_WEBHOOK_URL must be a URL." >&2
    exit 1
  fi
}

main() {
  check_args "$@"

  local body
  body="$(run_speedtest | to_slack_message "${1:-0}")"

  send_message "$body"
}

main "$@"