Merge pull request #186 from tegonal/feature/askWithTimeout

introduce askWithTimeout and reuse in askYesOrNo

src/utility/ask.sh

@@ -48,18 +48,17 @@ function askYesOrNo() {
 	local -r question=$1
 	shift || die "could not shift by 1"
 
-	# shellcheck disable=SC2059			# the question itself can have %s thus we use it in the format string
-	printf "\n\033[0;36m$question\033[0m y/[N]:" "$@"
+	local -r askYesOrNo_timeout=20
 	local answer='n'
-	local -r timeout=20
-	set +e
-	read -t "$timeout" -r answer
-	local lastResult=$?
-	set -e
-	if ((lastResult > 128)); then
+
+	# shellcheck disable=SC2317   # called by name
+	function askYesOrNo_noAnswerCallback() {
 		printf "\n"
-		logInfo "no user interaction after %s seconds, going to interpret that as a 'no'." "$timeout"
-	fi
+		logInfo "no user interaction after %s seconds, going to interpret that as a 'no'." "$askYesOrNo_timeout"
+	}
+
+	# shellcheck disable=SC2059			# the question itself can have %s thus we use it in the format string
+	askWithTimeout "\033[0;36m$question\033[0m y/[n]:" "$askYesOrNo_timeout" askYesOrNo_noAnswerCallback answer "" "$@"
 	if [[ $answer == y ]] || [[ $answer == Y ]]; then
 		return 0
 	elif [[ $answer == n ]] || [[ $answer == N ]]; then
@@ -69,3 +68,49 @@ function askYesOrNo() {
 		return 1
 	fi
 }
+
+function askWithTimeout() {
+	if (($# < 5)); then
+		logError "At least five arguments need to be passed to askWithTimeout, given \033[0;36m%s\033[0m\n" "$#"
+		echo >&2 '1: question   	the question which the user should answer'
+		echo >&2 '2: timeout			timeout in seconds after which we will call noAnswerFn'
+		echo >&2 '3: noAnswerFn		callback used in case we did not get an answer from the user'
+		echo >&2 '4: outVarName		name of output variable used to pass back the result'
+		echo >&2 '5: readArgs 		additional args passed to read'
+		echo >&2 '6... args...  	arguments for the question (question is printed with printf)'
+		printStackTrace
+		exit 9
+	fi
+	# prefixing all variables here as plan to write the answer to an variable which is not in scope of this function
+	# i.e. if we don't prefix and one using the same name for outVarName as a variable local to this function, then we
+	# would just assign a value to the local function instead of the variable defined outside this function. The prefix
+	# prevents such a clash in most likely all cases -- otherwise the user is to blame ;)
+	local -r askWithTimeout_question=$1
+	local -r askWithTimeout_timeout=$2
+	local -r askWithTimeout_noAnswerFn=$3
+	local -r askWithTimeout_outVarName=$4
+	local -r askWithTimeout_readArgs=$5
+	shift 5 || die "could not shift by 5"
+
+	exitIfArgIsNotFunction "$askWithTimeout_noAnswerFn" 3
+	# shellcheck disable=SC2059			# the question itself can have %s thus we use it in the format string
+	printf "\n$askWithTimeout_question " "$@"
+	local askWithTimeout_answer=''
+	set +e
+	if [[ -n $askWithTimeout_readArgs ]]; then
+		read -t "$askWithTimeout_timeout" "${askWithTimeout_readArgs?}" -r askWithTimeout_answer
+	else
+		read -t "$askWithTimeout_timeout" -r askWithTimeout_answer
+	fi
+
+	local askWithTimeout_lastResult=$?
+	set -e
+	if ((askWithTimeout_lastResult > 128)); then
+		"$askWithTimeout_noAnswerFn"
+	elif [[ $askWithTimeout_lastResult -eq 0 ]]; then
+		# that's where the black magic happens, we are assigning to a global (not local to this function) variable here
+		printf -v "$askWithTimeout_outVarName" "%s" "$askWithTimeout_answer" || die "could not assign value to $askWithTimeout_outVarName"
+	else
+		return "$askWithTimeout_lastResult"
+	fi
+}

src/utility/parse-args.sh

@@ -172,7 +172,7 @@ function parseArgumentsInternal {
 					printStackTrace
 					exit 9
 				fi
-				# that's where the black magic happens, we are assigning to global variables here
+				# that's where the black magic happens, we are assigning to global (not local to this function) variables here
 				printf -v "$parseArguments_paramName" "%s" "$2" || die "could not assign value to $parseArguments_paramName"
 				parseArguments_expectedName=1
 				((++parseArguments_numOfArgumentsParsed))