(log) File watching with citrus-framework - citrus-framework

Question

Is there a way and/or what are best practices to watch log files from the System Under Test?
My requirement is to validate presence/absence of log entries according known patterns produced by the SUT.
Thank you very much!

Answer 1

Well, I don't think there is a Citrus tool specifically designed for that. But I think that is a really good idea. You could open an issue and ask for this feature.
Meanwhile, here is a solution that we have used in one of our projects to check if the applicaiton log contained specific strings that were generated by our test.
sleep(2000),
echo("Searching the log..."),
new AbstractTestAction() {
#Override
public void doExecute(TestContext context) {
try {
String logfile = FileUtils.getFileContentAsString(Paths.get("target", "my-super-service.log").toAbsolutePath().normalize());
if (!logfile.contains("ExpectedException: ... | Details: BOOM!.")) {
throw new RuntimeException("Missing exceptions in log");
}
} catch (IOException e) {
throw new RuntimeException("Unable to get log");
}
}
}
OR you can replace that simple contains with a more elegant solution:
String grepResult = grepForLine(LOGFILE_PATH, ".*: SupermanMissingException.*");
if (grepResult == null) {
throw new RuntimeException("Expected error log entry not found");
}
The function goes over each line searching for a match to the regex supplied.
public String grepForLine(Path path, String regex) {
Pattern regexp = Pattern.compile(regex);
Matcher matcher = regexp.matcher("");
String msg = null;
try (
BufferedReader reader = Files.newBufferedReader(path, Charset.defaultCharset());
LineNumberReader lineReader = new LineNumberReader(reader)
) {
String line;
while ((line = lineReader.readLine()) != null) {
matcher.reset(line); //reset the input
if (matcher.find()) {
msg = "Line " + lineReader.getLineNumber() + " contains the error log: " + line;
}
}
} catch (IOException e) {
throw new RuntimeException(e);
}
return msg;
}