Added support for configurable regular expressions

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required (VERSION 3.7)
 project (expandurl-mastodon
-         VERSION 0.8.2
+         VERSION 0.9.0
          LANGUAGES CXX
 )
 

src/expandurl-mastodon.hpp

@@ -63,6 +63,15 @@ const string expand(const string &url);
  */
 const string strip(const string &url);
 
+/*!
+ *  @brief  Initialize replacements for URLs
+ *
+ *          If no replacements are found in the config file, a default list is
+ *          inserted.
+ *
+ */
+const void init_replacements();
+
 
 class Listener
 {

src/main.cpp

@@ -52,13 +52,15 @@ void signal_handler(int signum)
 
 int main(int argc, char *argv[])
 {
+    signal(SIGINT, signal_handler);
+    signal(SIGTERM, signal_handler);
+
     if (!configfile.read())
     {
         syslog(LOG_WARNING, "Could not open %s.", configfile.get_filepath().c_str());
     }
+    init_replacements();
 
-    signal(SIGINT, signal_handler);
-    signal(SIGTERM, signal_handler);
     curlpp::initialize();
     openlog("expandurl-mastodon", LOG_CONS | LOG_NDELAY | LOG_PID, LOG_LOCAL1);
     syslog(LOG_NOTICE, "Program started by user %d", getuid());

src/url.cpp

@@ -77,23 +77,39 @@ const string expand(const string &url)
 
 const string strip(const string &url)
 {
-    using replace_pair = std::pair<const std::regex, const std::string>;
     using namespace std::regex_constants;
+    Json::Value &config = configfile.get_json();
     string newurl = url;
 
-    const std::array<const replace_pair, 5> replace_array =
+    for (auto it = config["replace"].begin(); it != config["replace"].end();
-    {{
+         ++it)
-        { std::regex("[\\?&]utm_[^&]+", icase), "" },                   // Google
-        { std::regex("[\\?&]wtmc=[^&]+", icase), "" },                  // Twitter?
-        { std::regex("[\\?&]__twitter_impression=[^&]+", icase), "" },  // Twitter?
-        { std::regex("[\\?&]wt_zmc=[^&]+", icase), "" },                // Twitter?
-        { std::regex("//amp\\.", icase), "//" }                         // AMP
-    }};
-
-    for (const replace_pair &pair : replace_array)
     {
-        newurl = std::regex_replace(newurl, pair.first, pair.second);
+        newurl = std::regex_replace(newurl,
+                                    std::regex(it.name(), icase),
+                                    (*it).asString());
     }
 
     return newurl;
 }
+
+const void init_replacements()
+{
+    using replace_pair = std::pair<const std::string, const std::string>;
+    Json::Value &config = configfile.get_json();
+    if (config["replace"].isNull())
+    {
+        const std::array<const replace_pair, 5> replace_array =
+        {{
+            { "[\\?&]utm_[^&]+", "" },                      // Google
+            { "[\\?&]wtmc=[^&]+", "" },                     // Twitter?
+            { "[\\?&]__twitter_impression=[^&]+", "" },     // Twitter?
+            { "[\\?&]wt_zmc=[^&]+", "" },                   // Twitter?
+            { "//amp\\.", "//" }                            // AMP
+        }};
+
+        for (const replace_pair &pair : replace_array)
+        {
+            config["replace"][pair.first] = pair.second;
+        }
+    }
+}