[#3141] config parsers boilerplate

src/lib/dhcp/option4_dnr.cc

@@ -48,6 +48,11 @@ Option4Dnr::pack(OutputBuffer& buf, bool check) const {
 
 void
 Option4Dnr::unpack(OptionBufferConstIter begin, OptionBufferConstIter end) {
+    if (convenient_notation_) {
+        // parse convenient notation
+        std::string config_txt = std::string(begin, end);
+        parseConfigData(config_txt);
+    } else {
         setData(begin, end);
         while (begin != end) {
             DnrInstance dnr_instance(V4);
@@ -86,6 +91,7 @@ Option4Dnr::unpack(OptionBufferConstIter begin, OptionBufferConstIter end) {
             addDnrInstance(dnr_instance);
         }
     }
+}
 
 std::string
 Option4Dnr::toText(int indent) const {
@@ -119,6 +125,11 @@ Option4Dnr::addDnrInstance(DnrInstance& dnr_instance) {
     dnr_instances_.push_back(dnr_instance);
 }
 
+void
+Option4Dnr::parseConfigData(const std::string& config_txt) {
+    // TBD
+}
+
 const std::unordered_set<std::string> DnrInstance::FORBIDDEN_SVC_PARAMS = {"ipv4hint", "ipv6hint"};
 
 DnrInstance::DnrInstance(Option::Universe universe)

src/lib/dhcp/option4_dnr.h

@@ -546,6 +546,17 @@ private:
     /// @brief Flag stating whether the %Option was constructed with a convenient notation string,
     /// that needs custom parsing, or binary data.
     bool convenient_notation_;
+
+    /// @brief Parses a convenient notation of the option data, which may be used in config.
+    ///
+    /// As an alternative to the binary format,
+    /// we provide convenience option definition as a string in format:
+    /// TBD
+    ///
+    /// @param config_txt convenient notation of the option data received as string
+    ///
+    /// @throw BadValue Thrown in case parser found wrong format of received string.
+    void parseConfigData(const std::string& config_txt);
 };
 
 /// A pointer to the @c OptionDnr4 object.

src/lib/dhcp/option6_dnr.cc

@@ -55,6 +55,11 @@ Option6Dnr::packAddresses(util::OutputBuffer& buf) const {
 
 void
 Option6Dnr::unpack(OptionBufferConstIter begin, OptionBufferConstIter end) {
+    if (convenient_notation_) {
+        // parse convenient notation
+        std::string config_txt = std::string(begin, end);
+        parseConfigData(config_txt);
+    } else {
         if (std::distance(begin, end) < getMinimalLength()) {
             isc_throw(OutOfRange, getLogPrefix()
                                       << "data truncated to size " << std::distance(begin, end));
@@ -81,6 +86,7 @@ Option6Dnr::unpack(OptionBufferConstIter begin, OptionBufferConstIter end) {
         // SvcParams (variable length) field is last.
         unpackSvcParams(begin, end);
     }
+}
 
 std::string
 Option6Dnr::toText(int indent) const {
@@ -143,5 +149,10 @@ Option6Dnr::unpackAddresses(OptionBufferConstIter& begin, OptionBufferConstIter
     }
 }
 
+void
+Option6Dnr::parseConfigData(const std::string& config_txt){
+    // TBD
+}
+
 }  // namespace dhcp
 }  // namespace isc

src/lib/dhcp/option6_dnr.h

@@ -146,6 +146,17 @@ private:
     /// @brief Flag stating whether the %Option was constructed with a convenient notation string,
     /// that needs custom parsing, or binary data.
     bool convenient_notation_;
+
+    /// @brief Parses a convenient notation of the option data, which may be used in config.
+    ///
+    /// As an alternative to the binary format,
+    /// we provide convenience option definition as a string in format:
+    /// TBD
+    ///
+    /// @param config_txt convenient notation of the option data received as string
+    ///
+    /// @throw BadValue Thrown in case parser found wrong format of received string.
+    void parseConfigData(const std::string& config_txt);
 };
 
 /// A pointer to the @c Option6Dnr object.