DSL: add System.regex_match()

refs #7587

doc/18-library-reference.md

@@ -587,6 +587,65 @@ true
 false
 ```
 
+### regex\_match <a id="global-functions-regex_match"></a>
+
+Signature:
+
+```
+function regex_match(pattern, value)
+```
+
+If the regular expression `pattern` matches the string `value`,
+returns an array with the first match inside the whole string
+and the submatches of the match declared with parentheses.
+
+Otherwise returns null.
+
+Examples:
+
+```
+$ icinga2 console
+Icinga 2 (version: v2.13.0)
+<1> => regex_match("foo", "bar")
+null
+<2> => regex_match("foo", "foo")
+[ "foo" ]
+<3> => regex_match("f(o)o", "foo")
+[ "foo", "o" ]
+```
+
+```
+object Host "example.com" {
+  check_command = "passive"
+
+  vars.http_urls = [
+    "http://monitor.example.com/icingaweb2",
+    "https://logs.example.com",
+    "http://cloud.example.com:5000"
+  ]
+}
+
+apply Service "http-" for (url in host.vars.http_urls) {
+  check_command = "http"
+
+  var match = regex_match({{{http(s?)://([^:/]+)((?::\d+)?)((?:/.*)?)}}}, url)
+
+  if (match[1]) {
+    vars.http_ssl = true
+  }
+
+  vars.http_address = match[2]
+
+  if (match[3]) {
+    vars.http_port = match[3].substr(1)
+  }
+
+  if (match[4]) {
+    vars.http_uri = match[4]
+  }
+}
+```
+
 ### sleep <a id="global-functions-sleep"></a>
 
 Signature:

lib/base/scriptutils.cpp

@@ -18,6 +18,7 @@
 #include <boost/regex.hpp>
 #include <algorithm>
 #include <set>
+#include <utility>
 #ifdef _WIN32
 #include <msi.h>
 #endif /* _WIN32 */
@@ -25,6 +26,7 @@
 using namespace icinga;
 
 REGISTER_SAFE_FUNCTION(System, regex, &ScriptUtils::Regex, "pattern:text:mode");
+REGISTER_SAFE_FUNCTION(System, regex_match, &ScriptUtils::RegexMatch, "pattern:text");
 REGISTER_SAFE_FUNCTION(System, match, &ScriptUtils::Match, "pattern:text:mode");
 REGISTER_SAFE_FUNCTION(System, cidr_match, &ScriptUtils::CidrMatch, "pattern:ip:mode");
 REGISTER_SAFE_FUNCTION(System, len, &ScriptUtils::Len, "value");
@@ -148,6 +150,27 @@ bool ScriptUtils::Regex(const std::vector<Value>& args)
 	}
 }
 
+Array::Ptr ScriptUtils::RegexMatch(const String& pattern, const String& text)
+{
+	boost::regex expr (pattern.GetData());
+	boost::smatch what;
+
+	if (!boost::regex_search(text.GetData(), what, expr)) {
+		return nullptr;
+	}
+
+	Array::Ptr res = new Array();
+	ObjectLock oLock (res);
+
+	res->Reserve(what.size());
+
+	for (auto& submatch : what) {
+		res->Add(String(submatch.str()));
+	}
+
+	return std::move(res);
+}
+
 bool ScriptUtils::Match(const std::vector<Value>& args)
 {
 	if (args.size() < 2)

lib/base/scriptutils.hpp

@@ -24,6 +24,7 @@ public:
 	static double CastNumber(const Value& value);
 	static bool CastBool(const Value& value);
 	static bool Regex(const std::vector<Value>& args);
+	static Array::Ptr RegexMatch(const String& pattern, const String& text);
 	static bool Match(const std::vector<Value>& args);
 	static bool CidrMatch(const std::vector<Value>& args);
 	static double Len(const Value& value);

test/config-ops.cpp

@@ -158,6 +158,12 @@ BOOST_AUTO_TEST_CASE(advanced)
 	expr = ConfigCompiler::CompileText("<test>", R"(regex("^Hello", "Hello World"))");
 	BOOST_CHECK(expr->Evaluate(frame).GetValue());
 
+	expr = ConfigCompiler::CompileText("<test>", R"(regex_match("f(o)o", "foo") == [ "foo", "o" ])");
+	BOOST_CHECK(expr->Evaluate(frame).GetValue());
+
+	expr = ConfigCompiler::CompileText("<test>", R"(var nl = regex_match("f(o)o", "bar"); nl == null && typeof(nl) == Object)");
+	BOOST_CHECK(expr->Evaluate(frame).GetValue());
+
 	expr = ConfigCompiler::CompileText("<test>", "__boost_test()");
 	BOOST_CHECK_THROW(expr->Evaluate(frame).GetValue(), ScriptError);