[1781] introduced addRecordToNSEC3Zone interface to DB accessors.

this is the first step to support updating the NSEC3 namespace of a zone.
to help support various cases in addRRset() in a less expensive way,
introduced a helper RRParameterConverter class.
one simple test case was added to confirm the behavior.

src/lib/datasrc/database.cc

@@ -1191,31 +1191,80 @@ DatabaseUpdater::validateAddOrDelete(const char* const op_str,
     }
 }
 
+// This is a helper class used in adding/deleting RRsets to/from a database.
+// The purpose of this class is to provide conversion interface from various
+// parameters of the RRset to corresponding textual representations that the
+// underlying database interface expects.  The necessary parameters and how
+// to convert them depend on several things, such as whether it's NSEC3 related
+// or not, or whether journaling is requested.  In order to avoid unnecessary
+// conversion, this class also performs the conversion in a lazy manner.
+// Also, in order to avoid redundant conversion when the conversion is
+// requested for the same parameter multiple times, it remembers the
+// conversion result first time, and reuses it for subsequent requests
+// (this implicitly assumes copying std::string objects is not very expensive;
+// this is often the case in some common implementations that have
+// copy-on-write semantics for the string class).
+class RRParameterConverter {
+public:
+    RRParameterConverter(const AbstractRRset& rrset) : rrset_(rrset)
+    {}
+    const string& getName() {
+        if (name_.empty()) {
+            name_ = rrset_.getName().toText();
+        }
+        return (name_);
+    }
+    const string& getNSEC3Name() {
+        if (nsec3_name_.empty()) {
+            nsec3_name_ = rrset_.getName().split(0, 1).toText(true);
+        }
+        return (nsec3_name_);
+    }
+    const string& getRevName() {
+        if (revname_.empty()) {
+            revname_ = rrset_.getName().reverse().toText();
+        }
+        return (revname_);
+    }
+    const string& getTTL() {
+        if (ttl_.empty()) {
+            ttl_ = rrset_.getTTL().toText();
+        }
+        return (ttl_);
+    }
+    const string& getType() {
+        if (type_.empty()) {
+            type_ = rrset_.getType().toText();
+        }
+        return (type_);
+    }
+
+private:
+    string name_;
+    string nsec3_name_;
+    string revname_;
+    string ttl_;
+    string type_;
+    const AbstractRRset& rrset_;
+};
+
 void
 DatabaseUpdater::addRRset(const AbstractRRset& rrset) {
     validateAddOrDelete("add", rrset, DELETE, ADD);
 
     // It's guaranteed rrset has at least one RDATA at this point.
     RdataIteratorPtr it = rrset.getRdataIterator();
-
-    string columns[Accessor::ADD_COLUMN_COUNT]; // initialized with ""
-    columns[Accessor::ADD_NAME] = rrset.getName().toText();
-    columns[Accessor::ADD_REV_NAME] = rrset.getName().reverse().toText();
-    columns[Accessor::ADD_TTL] = rrset.getTTL().toText();
-    columns[Accessor::ADD_TYPE] = rrset.getType().toText();
-    string journal[Accessor::DIFF_PARAM_COUNT];
     if (journaling_) {
-        journal[Accessor::DIFF_NAME] = columns[Accessor::ADD_NAME];
-        journal[Accessor::DIFF_TYPE] = columns[Accessor::ADD_TYPE];
-        journal[Accessor::DIFF_TTL] = columns[Accessor::ADD_TTL];
         diff_phase_ = ADD;
         if (rrset.getType() == RRType::SOA()) {
-            serial_ =
-                dynamic_cast<const generic::SOA&>(it->getCurrent()).
+            serial_ = dynamic_cast<const generic::SOA&>(it->getCurrent()).
                 getSerial();
         }
     }
+
+    RRParameterConverter cvtr(rrset);
     for (; !it->isLast(); it->next()) {
+        string sigtype;
         if (rrset.getType() == RRType::RRSIG()) {
             // XXX: the current interface (based on the current sqlite3
             // data source schema) requires a separate "sigtype" column,
@@ -1224,16 +1273,25 @@ DatabaseUpdater::addRRset(const AbstractRRset& rrset) {
             // the interface, but until then we have to conform to the schema.
             const generic::RRSIG& rrsig_rdata =
                 dynamic_cast<const generic::RRSIG&>(it->getCurrent());
-            columns[Accessor::ADD_SIGTYPE] =
-                rrsig_rdata.typeCovered().toText();
+            sigtype = rrsig_rdata.typeCovered().toText();
         }
-        columns[Accessor::ADD_RDATA] = it->getCurrent().toText();
+        const string rdata = it->getCurrent().toText();
         if (journaling_) {
-            journal[Accessor::DIFF_RDATA] = columns[Accessor::ADD_RDATA];
+            const string journal[Accessor::DIFF_PARAM_COUNT] =
+                { cvtr.getName(), cvtr.getType(), cvtr.getTTL(), rdata };
             accessor_->addRecordDiff(zone_id_, serial_.getValue(),
                                      Accessor::DIFF_ADD, journal);
         }
-        accessor_->addRecordToZone(columns);
+        if (rrset.getType() == RRType::NSEC3()) {
+            const string nsec3_columns[Accessor::ADD_NSEC3_COLUMN_COUNT] =
+                { cvtr.getNSEC3Name(), cvtr.getTTL(), cvtr.getType(), rdata };
+            accessor_->addRecordToNSEC3Zone(nsec3_columns);
+        } else {
+            const string columns[Accessor::ADD_COLUMN_COUNT] =
+                { cvtr.getName(), cvtr.getRevName(), cvtr.getTTL(),
+                  cvtr.getType(), sigtype, rdata };
+            accessor_->addRecordToZone(columns);
+        }
     }
 }
 

src/lib/datasrc/database.h

@@ -95,6 +95,16 @@ public:
         ADD_COLUMN_COUNT = 6 ///< Number of columns
     };
 
+    enum AddNSEC3RecordColumns {
+        ADD_NSEC3_HASH = 0, ///< The owner name of the record (a domain name)
+        ADD_NSEC3_TTL = 1,  ///< The TTL of the record (in numeric form)
+        ADD_NSEC3_TYPE = 2, ///< The RRType of the record (either NSEC3 or
+                            ///< RRSIG)
+        ADD_NSEC3_RDATA = 3, ///< Full text representation of the record's
+                             ///< RDATA
+        ADD_NSEC3_COLUMN_COUNT = 4 ///< Number of columns
+    };
+
     /// \brief Definitions of the fields to be passed to deleteRecordInZone()
     ///
     /// Each derived implementation of deleteRecordInZone() should expect
@@ -432,6 +442,9 @@ public:
     virtual void addRecordToZone(
         const std::string (&columns)[ADD_COLUMN_COUNT]) = 0;
 
+    virtual void addRecordToNSEC3Zone(
+        const std::string (&columns)[ADD_NSEC3_COLUMN_COUNT]) = 0;
+
     /// \brief Delete a single record from the zone to be updated.
     ///
     /// This method provides a simple interface to delete a record
@@ -684,7 +697,7 @@ public:
     /// This is used to find previous NSEC3 hashes, to find covering NSEC3 in
     /// case none match exactly.
     ///
-    /// In case a hash before before the lowest or the lowest is provided,
+    /// In case a hash before the lowest or the lowest is provided,
     /// this should return the largest one in the zone (NSEC3 needs a
     /// wrap-around semantics).
     ///

src/lib/datasrc/sqlite3_accessor.cc

@@ -1122,6 +1122,13 @@ SQLite3Accessor::addRecordToZone(const string (&columns)[ADD_COLUMN_COUNT]) {
 }
 
 void
+SQLite3Accessor::addRecordToNSEC3Zone(
+    const string (&/*columns*/)[ADD_NSEC3_COLUMN_COUNT])
+{
+    isc_throw(NotImplemented, "not yet implemented");
+}
+
+void
 SQLite3Accessor::deleteRecordInZone(const string (&params)[DEL_PARAM_COUNT]) {
     if (!dbparameters_->updating_zone) {
         isc_throw(DataSourceError, "deleting record in SQLite3 "

src/lib/datasrc/sqlite3_accessor.h

@@ -214,6 +214,9 @@ public:
     virtual void addRecordToZone(
         const std::string (&columns)[ADD_COLUMN_COUNT]);
 
+    virtual void addRecordToNSEC3Zone(
+        const std::string (&columns)[ADD_NSEC3_COLUMN_COUNT]);
+
     virtual void deleteRecordInZone(
         const std::string (&params)[DEL_PARAM_COUNT]);
 

src/lib/datasrc/tests/database_unittest.cc

@@ -14,6 +14,7 @@
 
 #include <exceptions/exceptions.h>
 
+#include <dns/masterload.h>
 #include <dns/name.h>
 #include <dns/rrttl.h>
 #include <dns/rrset.h>
@@ -29,6 +30,7 @@
 
 #include <gtest/gtest.h>
 
+#include <boost/bind.hpp>
 #include <boost/shared_ptr.hpp>
 #include <boost/lexical_cast.hpp>
 
@@ -247,6 +249,8 @@ public:
     virtual void commit() {}
     virtual void rollback() {}
     virtual void addRecordToZone(const string (&)[ADD_COLUMN_COUNT]) {}
+    virtual void addRecordToNSEC3Zone(const string (&)[ADD_NSEC3_COLUMN_COUNT])
+    {}
     virtual void deleteRecordInZone(const string (&)[DEL_PARAM_COUNT]) {}
     virtual void addRecordDiff(int, uint32_t, DiffOperation,
                                const std::string (&)[DIFF_PARAM_COUNT]) {}
@@ -687,6 +691,7 @@ public:
     virtual void commit() {
         *readonly_records_ = *update_records_;
     }
+
     virtual void rollback() {
         // Special hook: if something with a name of "throw.example.org"
         // has been added, trigger an imaginary unexpected event with an
@@ -697,6 +702,7 @@ public:
 
         rollbacked_ = true;
     }
+
     virtual void addRecordToZone(const string (&columns)[ADD_COLUMN_COUNT]) {
         // Copy the current value to cur_name.  If it doesn't exist,
         // operator[] will create a new one.
@@ -718,6 +724,17 @@ public:
              columns_lastadded_);
     }
 
+    virtual void addRecordToNSEC3Zone(
+        const string (&columns)[ADD_NSEC3_COLUMN_COUNT])
+    {
+        columns_lastadded_[ADD_NAME] = columns[ADD_NSEC3_HASH];
+        columns_lastadded_[ADD_REV_NAME].clear();
+        columns_lastadded_[ADD_TTL] = columns[ADD_NSEC3_TTL];
+        columns_lastadded_[ADD_TYPE] = columns[ADD_NSEC3_TYPE];
+        columns_lastadded_[ADD_SIGTYPE].clear();
+        columns_lastadded_[ADD_RDATA] = columns[ADD_NSEC3_RDATA];
+    }
+
     // Helper predicate class used in deleteRecordInZone().
     struct deleteMatch {
         deleteMatch(const string& type, const string& rdata) :
@@ -2693,6 +2710,42 @@ TYPED_TEST(DatabaseClientTest, addRRsetToNewZone) {
     this->checkLastAdded(rrset_added);
 }
 
+// TODO: maybe we should share this stuff
+// A helper callback of masterLoad() used in InMemoryZoneFinderTest.
+void
+setRRset(RRsetPtr rrset, vector<RRsetPtr*>::iterator& it) {
+    *(*it) = rrset;
+    ++it;
+}
+
+ConstRRsetPtr
+textToRRset(const string& text_rrset, const RRClass& rrclass = RRClass::IN()) {
+    stringstream ss(text_rrset);
+    RRsetPtr rrset;
+    vector<RRsetPtr*> rrsets;
+    rrsets.push_back(&rrset);
+    masterLoad(ss, Name::ROOT_NAME(), rrclass,
+               boost::bind(setRRset, _1, rrsets.begin()));
+    return (rrset);
+}
+
+// Right now this only works for the mock DB, but the plan is to make it
+// a TYPED_TEST to share the case with SQLite3 implementation, too.
+TEST_F(MockDatabaseClientTest, addNSEC3ToZone) {
+    const char* const nsec3_hash = "1BB7SO0452U1QHL98UISNDD9218GELR5";
+    const char* const nsec3_rdata = "1 1 12 AABBCCDD "
+        "2T7B4G4VSA5SMI47K61MV5BV1A22BOJR NS SOA RRSIG NSEC3PARAM";
+
+    this->updater_ = this->client_->getUpdater(this->zname_, true);
+    this->updater_->addRRset(
+        *textToRRset(string(nsec3_hash) + ".example.org. 3600 IN NSEC3 " +
+                     string(nsec3_rdata)));
+    this->updater_->commit();
+    const char* const rrset_added[] = {
+        nsec3_hash, "", "3600", "NSEC3", "", nsec3_rdata };
+    this->checkLastAdded(rrset_added);
+}
+
 TYPED_TEST(DatabaseClientTest, addRRsetToCurrentZone) {
     // Similar to the previous test, but not replacing the existing data.
     boost::shared_ptr<DatabaseClient::Finder> finder(this->getFinder());