Update genkeys() interface

DESCRIPTION

@@ -21,10 +21,14 @@ LazyData: true
 BugReports: https://github.com/SurgicalInformatics/encryptr/issues
 URL: https://github.com/SurgicalInformatics/encryptr
 Imports:
+    askpass,
     dplyr,
     knitr,
     openssl,
     purrr,
     readr,
     rlang
 RoxygenNote: 6.1.0
+Suggests: 
+    testthat,
+    withr

R/genkeys.R

@@ -10,6 +10,8 @@
 #'   reason.
 #' @param public_key_name Character string. Do not change default unless good
 #'   reason.
+#' @param password Password for private key. This password cannot be recovered
+#'   if lost, so please store the password in a safe location.
 #'
 #' @return Two files containing the public key and encrypted private key are
 #'   written to the working directory.
@@ -19,7 +21,9 @@
 #'
 #' @examples
 #' genkeys()
-genkeys <- function(private_key_name = "id_rsa", public_key_name = "id_rsa.pub"){
+genkeys <- function(private_key_name = "id_rsa",
+                    public_key_name = paste0(private_key_name, ".pub"),
+                    password = ask_pass()){
   if(file.exists(private_key_name)){
     stop("Private key file with this name already exists. Delete it or change file name.")
   }
@@ -30,11 +34,14 @@ genkeys <- function(private_key_name = "id_rsa", public_key_name = "id_rsa.pub")
   key <- openssl::rsa_keygen()
   pubkey <- as.list(key)$pubkey
 
-  openssl::write_pem(key,
-                     "id_rsa",
-                     password = openssl::askpass(prompt = "Please choose a password for your private key.
-                                                 This password CANNOT be recovered if lost.
-                                                 Please store the password in a safe location."))
-  openssl::write_pem(pubkey,
-                     "id_rsa.pub")
+  openssl::write_pem(key, private_key_name, password = password)
+  openssl::write_pem(pubkey, public_key_name)
+}
+
+ask_pass <- function() {
+  askpass::askpass(prompt = paste(
+    "Please choose a password for your private key.",
+    "This password CANNOT be recovered if lost.",
+    "Please store the password in a safe location.",
+    sep = "\n"))
 }

tests/testthat.R

@@ -0,0 +1,4 @@
+library(testthat)
+library(encryptr)
+
+test_check("encryptr")

tests/testthat/test-genkeys.R

@@ -0,0 +1,54 @@
+context("test-genkeys")
+
+# Run tests in temp directory
+# https://github.com/r-lib/testthat/issues/664#issuecomment-340809997
+
+dir_empty <- function(x){
+  unlink(x, recursive = TRUE, force = TRUE)
+  dir.create(x)
+}
+
+test_with_dir <- function(desc, ...){
+  new <- tempfile()
+  dir_empty(new)
+  withr::with_dir( # or local_dir()
+    new = new,
+    code = {
+      tmp <- capture.output(
+        testthat::test_that(desc = desc, ...)
+      )
+    }
+  )
+  invisible()
+}
+
+test_with_dir("genkeys() defaults create id_rsa and id_rsa.pub", {
+  genkeys(password = NULL)
+  expect_true(file.exists("id_rsa"))
+  expect_true(file.exists("id_rsa.pub"))
+})
+
+test_with_dir("genkeys() errors if files already exist", {
+  file.create("id_rsa.pub")
+  expect_error(genkeys(password = NULL), regexp = "Public key .+ exists")
+  file.create("id_rsa")
+  expect_error(genkeys(password = NULL), regexp = "Private key .+ exists")
+})
+
+test_with_dir("genkeys() creates keys with requested names", {
+  genkeys("custom", password = NULL)
+  expect_true(file.exists("custom"))
+  expect_true(file.exists("custom.pub"))
+
+  genkeys("public", "private", password = NULL)
+  expect_true(file.exists("public"))
+  expect_true(file.exists("private"))
+})
+
+test_with_dir("genkeys() uses password argument", {
+  genkeys(password = "testpassword")
+  check_message <- "Message"
+  x <- openssl::rsa_encrypt(charToRaw(check_message), "id_rsa.pub")
+  y <- openssl::rsa_decrypt(x, "id_rsa", "testpassword")
+  expect_equal(rawToChar(y), check_message)
+})