#183: Error handling for the connection object being made before star…

…t_db_capturing() (#186)

NAMESPACE

@@ -3,6 +3,7 @@
 export(.db_mock_paths)
 export(.dittodb_env)
 export(capture_db_requests)
+export(check_db_path)
 export(check_for_pkg)
 export(clean_statement)
 export(dbMockConnect)

NEWS.md

@@ -1,4 +1,5 @@
 # dittodb (development version)
+* Improved error messages for connections made before running `start_db_capture()`. (#183)
 * Added to the `dbplyr` unique table names that are ignored to work with the newest `dbplyr` table names. (#188)
 
 # dittodb 0.1.7

R/capture-requests.R

@@ -202,6 +202,8 @@ dbConnectTrace <- quote({
 })
 
 dbSendQueryTrace <- quote({
+  check_db_path(.dittodb_env)
+
   if (dittodb_debug_level(2)) {
     message(
       "The statement: \n", statement,
@@ -222,6 +224,7 @@ dbSendQueryTrace <- quote({
 })
 
 dbListTablesTrace <- quote({
+  check_db_path(.dittodb_env)
   thing <- returnValue()
   dput(
     thing,
@@ -231,6 +234,7 @@ dbListTablesTrace <- quote({
 })
 
 dbListFieldsTrace <- quote({
+  check_db_path(.dittodb_env)
   thing <- returnValue()
   name <- sanitize_table_id(name, ...)
   dput(
@@ -241,6 +245,7 @@ dbListFieldsTrace <- quote({
 })
 
 dbExistsTableTrace <- quote({
+  check_db_path(.dittodb_env)
   thing <- returnValue()
   name <- sanitize_table_id(name, ...)
   dput(
@@ -429,3 +434,26 @@ get_redactor <- function() {
 
   return(NULL)
 }
+
+#' Check dittodb environment path
+#'
+#' This function should generally not be used, but must be exported for the
+#' query recording function to work properly
+#'
+#' @param .dittodb_env Environment object
+#'
+#' @return `NULL`, invisibly.
+#' @export
+check_db_path <- function(.dittodb_env) {
+  if (is.null(.dittodb_env$db_path)) {
+    rlang::abort(
+      message = c("Database capture failed",
+        "*" = "The database connection object was created before calling 'start_db_capturing()'",
+        "*" = "Please ensure the connection is created after calling 'start_db_capturing()'."
+      ),
+      call = rlang::caller_env()
+    )
+  }
+
+  return(invisible())
+}

tests/testthat/test-a-recording.R

@@ -43,3 +43,41 @@ test_that("We can specify the path when starting capture", {
   dbDisconnect(con)
   stop_db_capturing()
 })
+
+test_that("dbGetQuery error checking", {
+  # Check to make sure con was not created before start_db_capturing()
+  suppressMessages(con <- nycflights13_create_sqlite(verbose = FALSE))
+
+  start_db_capturing()
+
+  # Testthat sets this to "tests/testthat//_memory_"
+  # Setting this to NULL so it will mimic a developers experience
+  .dittodb_env$db_path <- NULL
+
+  regex_db <- "^Database capture failed"
+
+  error_get_query <- expect_error(
+    object = dbGetQuery(con, "SELECT * FROM airlines"),
+    regexp = regex_db
+  )
+
+  testthat_transition(
+    old = expect_error(dbListTables(con), regex_db),
+    new = expect_error(expect_error(dbListTables(con)), regex_db)
+  )
+
+  testthat_transition(
+    old = expect_error(dbListFields(con, "airlines"), regex_db),
+    new = expect_error(expect_error(dbListFields(con, "airlines")), regex_db)
+  )
+
+  testthat_transition(
+    old = expect_error(dbExistsTable(con, "airlines"), regex_db),
+    new = expect_error(expect_error(dbExistsTable(con, "airlines")), regex_db)
+  )
+
+  error_tbl <- expect_error(dplyr::tbl(con, "airlines"), regex_db)
+
+  suppressWarnings(dbDisconnect(con))
+  stop_db_capturing()
+})