Add rsyslog plugin and tests

src/sonic-eventd/rsyslog_plugin/main.cpp

@@ -0,0 +1,49 @@
+#include <iostream>
+#include <unistd.h>
+#include "rsyslog_plugin.h"
+#include "syslog_parser.h"
+
+using namespace std;
+
+void showUsage() {
+    cerr << "Usage for rsyslog_plugin: " << " <option(s)> SOURCES\n"
+        << "Options:\n"
+        << "\t-r,required,type=string\t\tPath to regex file"
+        << "\t-m,required,type=string\t\tYANG module name of source generating syslog message"
+        << endl;
+}
+
+int main(int argc, char** argv) {
+    string regex_path;
+    string module_name;
+    int option_val;
+
+    while((option_val = getopt(argc, argv, "r:m:")) != -1) {
+        switch(option_val) {
+            case 'r':
+                if(optarg != NULL) {
+                    regex_path = optarg;
+                }
+                break;
+            case 'm':
+                if(optarg != NULL) {
+                    module_name = optarg;
+                }
+                break;
+            default:
+                showUsage();
+                return 1;
+        }
+    }
+
+    if(regex_path.empty() || module_name.empty()) { // Missing required rc path
+        showUsage();
+        return 1;
+    }
+
+    SyslogParser* parser = new SyslogParser({}, json::array());
+    RsyslogPlugin* plugin = new RsyslogPlugin(parser, module_name, regex_path);
+
+    plugin->run();
+    return 0;
+}

src/sonic-eventd/rsyslog_plugin/rsyslog_plugin.cpp

@@ -0,0 +1,77 @@
+#include <ios>
+#include <iostream>
+#include <vector>
+#include <fstream>
+#include <regex>
+#include "rsyslog_plugin.h"
+#include "common/logger.h"
+#include "common/json.hpp"
+#include "common/events.h"
+
+using namespace std;
+using namespace swss;
+using json = nlohmann::json;
+
+void RsyslogPlugin::onMessage(string msg) {
+    string tag = "";
+    event_params_t param_dict;
+    if(!parser->parseMessage(msg, tag, param_dict)) {
+        SWSS_LOG_INFO("%s was not able to be parsed into a structured event\n", msg.c_str());
+    } else {
+	int return_code = event_publish(fetchHandle(), tag, &param_dict);
+	if (return_code != 0) {
+            SWSS_LOG_INFO("rsyslog_plugin was not able to publish event for %s\n", tag.c_str());
+	}
+    }
+}
+
+[[noreturn]] void RsyslogPlugin::run() {
+    while(true) {
+        string line;
+        getline(cin, line);
+        if(line.empty()) {
+            continue;
+        }
+        onMessage(line);
+    }
+}
+
+bool RsyslogPlugin::createRegexList() {
+    fstream regex_file;
+    regex_file.open(regex_path, ios::in);
+    if (!regex_file) {
+        SWSS_LOG_ERROR("No such path exists: %s for source %s\n", regex_path.c_str(), module_name.c_str());
+        return false;
+    }
+    try {
+        regex_file >> parser->regex_list;
+    } catch (exception& exception) {
+        SWSS_LOG_ERROR("Invalid JSON file: %s, throws exception: %s\n", regex_path.c_str(), exception.what());
+        return false;
+    }
+
+    string regex_string = "";
+    regex expression;
+
+    for(long unsigned int i = 0; i < parser->regex_list.size(); i++) {
+        try {
+            regex_string = parser->regex_list[i]["regex"];
+            regex expr(regex_string);
+            expression = expr;
+        } catch (exception& exception) {
+            SWSS_LOG_ERROR("Invalid regex, throws exception: %s\n", exception.what());
+            return false;
+        }
+        parser->expressions.push_back(expression);
+    }
+    regex_file.close();
+    return true;
+}
+
+
+RsyslogPlugin::RsyslogPlugin(SyslogParser* syslog_parser, string mod_name, string path) {
+    parser = syslog_parser;
+    module_name = mod_name;
+    regex_path = path;
+    onInit();
+}

src/sonic-eventd/rsyslog_plugin/rsyslog_plugin.h

@@ -0,0 +1,43 @@
+#ifndef RSYSLOG_PLUGIN_H
+#define RSYSLOG_PLUGIN_H
+
+#include <string>
+#include <fstream>
+#include "syslog_parser.h"
+#include "common/logger.h"
+#include "common/events.h"
+
+using namespace std;
+using json = nlohmann::json;
+
+/**
+ * Rsyslog Plugin will utilize an instance of a syslog parser to read syslog messages from rsyslog.d and will continuously read from stdin
+ * A plugin instance is created for each container/host.
+ *
+ */
+
+class RsyslogPlugin {
+public:
+    RsyslogPlugin(SyslogParser* syslog_parser, string mod_name, string path);
+    void onMessage(string msg);
+    void run();
+    bool createRegexList();
+    event_handle_t fetchHandle() {
+        return event_handle;
+    }
+    SyslogParser* parser;
+private:
+    string regex_path;
+    string module_name;
+    event_handle_t event_handle;
+
+    bool onInit() {
+        event_handle = events_init_publisher(module_name);
+        int return_code = createRegexList();
+	return (event_handle != NULL || return_code == 0); 
+    }
+
+};
+
+#endif
+

src/sonic-eventd/rsyslog_plugin/syslog_parser.cpp

@@ -0,0 +1,49 @@
+#include <iostream>
+#include <ios>
+#include <fstream>
+#include <regex>
+#include "syslog_parser.h"
+#include "common/logger.h"
+
+
+using namespace std;
+/**
+ * Parses syslog message and returns structured event
+ *
+ * @param nessage us syslog message being fed in by rsyslog.d
+ * @return return structured event json for publishing
+ *
+*/
+
+bool SyslogParser::parseMessage(string message, string& event_tag, event_params_t& param_map) {
+    for(long unsigned int i = 0; i < regex_list.size(); i++) {
+        smatch match_results;
+	regex_search(message, match_results, expressions[i]);
+	vector<string> groups;
+	vector<string> params;
+	try {
+	    event_tag = regex_list[i]["tag"];
+	    vector<string> p = regex_list[i]["params"];
+	    params = p;
+	} catch (exception& exception) {
+	    SWSS_LOG_ERROR("Invalid regex list, throws exception: %s\n", exception.what());
+	    return false;
+	}
+	// first match in groups is entire message
+	for(long unsigned int j = 1; j < match_results.size(); j++) {
+	    groups.push_back(match_results.str(j));
+	}
+	if (groups.size() == params.size()) { // found matching regex
+            transform(params.begin(), params.end(), groups.begin(), inserter(param_map, param_map.end()), [](string a, string b) {
+	        return make_pair(a,b);
+	    });
+	    return true;
+	}
+    }
+    return false;
+}
+
+SyslogParser::SyslogParser(vector<regex> regex_expressions, json list) {
+    expressions = regex_expressions;
+    regex_list = list;
+}

src/sonic-eventd/rsyslog_plugin/syslog_parser.h

@@ -0,0 +1,28 @@
+#ifndef SYSLOG_PARSER_H
+#define SYSLOG_PARSER_H
+
+#include <vector>
+#include <string>
+#include <regex>
+#include "common/json.hpp"
+#include "common/events.h"
+
+using namespace std;
+using json = nlohmann::json;
+
+/**
+ * Syslog Parser is responsible for parsing log messages fed by rsyslog.d and returns
+ * matched result to rsyslog_plugin to use with events publish API
+ *
+ */
+
+class SyslogParser {
+public:
+    SyslogParser(vector<regex> regex_expressions, json list);
+    bool parseMessage(string message, string& tag, event_params_t& param_dict);
+
+    vector<regex> expressions;
+    json regex_list = json::array();
+};
+
+#endif

src/sonic-eventd/rsyslog_plugin_tests/rsyslog_plugin_ut.cpp

@@ -0,0 +1,125 @@
+#include <iostream>
+#include <fstream>
+#include <regex>
+#include "gtest/gtest.h"
+#include "common/json.hpp"
+#include "common/events.h"
+#include "rsyslog_plugin/rsyslog_plugin.h"
+#include "rsyslog_plugin/syslog_parser.h"
+
+using namespace std;
+using json = nlohmann::json;
+
+RsyslogPlugin* plugin = NULL;
+
+json j_list_1 = json::array();
+json j_list_2 = json::array();
+vector<regex> test_expressions_1;
+vector<regex> test_expressions_2;
+
+void createTests() {
+    string regex_string_1 = "timestamp (.*) message (.*) other_data (.*)";
+    string regex_string_2 = "no match";
+
+    json j_test_1;
+    j_test_1["tag"] = "test_tag_1";
+    j_test_1["regex"] = regex_string_1;
+    j_test_1["params"] = { "timestamp", "message", "other_data" };
+    j_list_1.push_back(j_test_1);
+
+    json j_test_2;
+    j_test_2["tag"] = "test_tag_2";
+    j_test_2["regex"] = regex_string_2;
+    j_test_2["params"] = {};
+    j_list_2.push_back(j_test_2);
+
+    regex expression_1(regex_string_1);
+    test_expressions_1.push_back(expression_1);
+    regex expression_2(regex_string_2);
+    test_expressions_2.push_back(expression_2);
+}
+
+
+TEST(syslog_parser, matching_regex) {
+    createTests();
+    string tag = "";
+    event_params_t param_dict;
+
+    event_params_t expected_dict;
+    expected_dict["timestamp"] = "test_timestamp";
+    expected_dict["message"] = "test_message";
+    expected_dict["other_data"] = "test_data";
+
+    SyslogParser* parser = new SyslogParser(test_expressions_1, j_list_1);
+
+    bool success = parser->parseMessage("timestamp test_timestamp message test_message other_data test_data", tag, param_dict);
+    EXPECT_EQ(true, success);
+    EXPECT_EQ("test_tag_1", tag);
+    EXPECT_EQ(expected_dict, param_dict);
+
+    delete parser;
+}
+
+TEST(syslog_parser, no_matching_regex) {
+    string tag = "";
+    event_params_t param_dict;
+    SyslogParser* parser = new SyslogParser(test_expressions_2, j_list_2);
+    bool success = parser->parseMessage("Test Message", tag, param_dict);
+    EXPECT_EQ(false, success);
+    delete parser;
+}
+
+
+void createPlugin(string path) {
+    SyslogParser* testParser = new SyslogParser({}, json::array());
+    plugin = new RsyslogPlugin(testParser, "test_mod_name", path);
+}
+
+TEST(rsyslog_plugin, createRegexList_invalidJS0N) {
+    createPlugin("./test_regex_1.rc.json");
+    if(plugin != NULL) {
+        EXPECT_EQ(false, plugin->createRegexList());
+    }
+    delete plugin;
+}
+
+TEST(rsyslog_plugin, createRegexList_missingRegex) {
+    createPlugin("./test_regex_3.rc.json");
+    if(plugin != NULL) {
+	EXPECT_EQ(false, plugin->createRegexList());
+    }
+    delete plugin;
+}
+
+TEST(rsyslog_plugin, createRegexList_invalidRegex) {
+    createPlugin("./test_regex_4.rc.json");
+    if(plugin != NULL) {
+	EXPECT_EQ(false, plugin->createRegexList());
+    }
+    delete plugin;
+}
+
+TEST(rsyslog_plugin, createRegexList_validRegex) {
+    createPlugin("./test_regex_2.rc.json");
+    if(plugin != NULL) {
+	auto parser = plugin->parser;
+	EXPECT_EQ(1, parser->regex_list.size());
+	EXPECT_EQ(1, parser->expressions.size());
+
+	ifstream infile("test_syslogs.txt");
+	string log_message;
+	bool parse_result;
+
+	while(infile >> log_message >> parse_result) {
+	    string tag = "";
+	    event_params_t param_dict;
+	    EXPECT_EQ(parse_result, parser->parseMessage(log_message, tag, param_dict));
+	}
+    }
+    delete plugin;
+}
+
+int main(int argc, char* argv[]) {
+    testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}

src/sonic-eventd/rsyslog_plugin_tests/test_regex_1.rc.json

@@ -0,0 +1 @@
+*

src/sonic-eventd/rsyslog_plugin_tests/test_regex_2.rc.json

@@ -0,0 +1,7 @@
+[
+    {
+        "tag": "bgp-state",
+	"regex": "([a-zA-Z]{3} [0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2}.[0-9]{0,6}) .* %ADJCHANGE: neighbor (.*) (Up|Down) .*",
+	"params": [ "timestamp", "neighbor_ip", "state" ]
+    }
+]

src/sonic-eventd/rsyslog_plugin_tests/test_regex_3.rc.json

@@ -0,0 +1,6 @@
+[
+    {
+        "tag": "TEST-TAG-NO-REGEX",
+	"param": []
+    }
+]