Script to analyse Gmail message sizes by from/to/subject, useful when you're running out of space in the free tier

gmail_message_size_analysis.R

# Script to analyse Gmail message sizes by from/to/subject

# 1. Download Gmail from Google Takeout, specifically the folders "Inbox",
# "Archived", "Sent", and "Bin".
# 2. Extract it into the working directory.  It should create the folders
# Takeout/Mail
# 3. Run this script in the working directory

library(tidyverse)
library(tm.plugin.mail)
library(fs)
library(processx)
library(sitools) # For Gigabyte ggplot2 scale
library(here)

box_data <- function(box, overwrite = FALSE, sender = TRUE, recipients = FALSE) {
  unbox <- here("data", tolower(box))
  mbox <- here("Takeout", "Mail", paste0(box, ".mbox"))

  dir_create(unbox)
  if (overwrite) {
    if (dir_exists(unbox)) dir_delete(unbox)

    cat("Splitting mbox file\n")
    system(paste0("perl -pe 'open STDOUT, \">", unbox, "/\".++$n if /^From /' < ", mbox))
  }


  # Collect the file names
  cat("Collecting file names\n")
  files <- dir_ls(unbox, full.names = TRUE)

  # Collect the file sizes
  cat("Collecting file sizes\n")
  size <- tibble(file = files, size = file_size(files))

  if (sender) {
    # Collect the "From:" addresses
    cat("Collecting sender details\n")
    from <-
      run(
        "rg",
        c(
          "--no-heading", # No empty lines between matches
          "--with-filename", # Filename beside every match
          "--no-line-number",
          "-i", # Case insensitive
          "-m", 1, # Return only the first match
          "(^from: ?)(.*)", # Address and sometimes name of sender
          "--replace", "$2", # Don't return the "From: " prefix
          unbox
        )
      ) %>%
      pluck("stdout") %>%
      read_lines() %>%
      tibble(string = .) %>%
      separate(
        col = string,
        into = c(
          "file",
          "from"
        ),
        sep = ":",
        extra = "merge"
      )
  } else {
    from <- tibble(file = character(0), from = character(0))
  }

  if (recipients) {
    # Collect the "From:" addresses
    cat("Collecting recipient details\n")
    to <-
      run(
        "rg",
        c(
          "--no-heading", # No empty lines between matches
          "--with-filename", # Filename beside every match
          "--no-line-number",
          "-i", # Case insensitive
          "-m", 1, # Return only the first match
          "(^to: ?)(.*)", # Address and sometimes name of sender
          "--replace", "$2", # Don't return the "From: " prefix
          unbox
        )
      ) %>%
      pluck("stdout") %>%
      read_lines() %>%
      tibble(string = .) %>%
      separate(
        col = string,
        into = c(
          "file",
          "to"
        ),
        sep = ":",
        extra = "merge"
      )
  } else {
    to <- tibble(file = character(0), to = character(0))
  }

  # Collect the "Subject:"
  cat("Collecting subjects\n")
  subject <-
    run(
      "rg",
      c(
        "--no-heading", # No empty lines between matches
        "--with-filename", # Filename beside every match
        "--no-line-number",
        "-i", # Case insensitive
        "-m", 1, # Return only the first match
        "(^subject: ?)(.*)", # Address and sometimes name of sender
        "--replace", "$2", # Don't return the "From: " prefix
        unbox
      )
    ) %>%
    pluck("stdout") %>%
    read_lines() %>%
    tibble(string = .) %>%
    separate(
      col = string,
      into = c(
        "file",
        "subject"
      ),
      sep = ":",
      extra = "merge"
    )

  cat("Returning dataset\n")

  size %>%
    left_join(from, by = "file") %>%
    left_join(to, by = "file") %>%
    left_join(subject, by = "file")
}

inbox <- box_data("Inbox")
bin <- box_data("Bin")
archived <- box_data("Archived")
sent <- box_data("Sent", sender = FALSE, recipients = TRUE)

all <- bind_rows(
  inbox = inbox, bin = bin, archived = archived, sent = sent,
  .id = "box"
)