[2575] define IF of deleteZone() and implement it for SQLite3.

src/lib/datasrc/database.h

@@ -155,7 +155,7 @@ public:
     ///
     /// It is empty, but needs a virtual one, since we will use the derived
     /// classes in polymorphic way.
-    virtual ~DatabaseAccessor() { }
+    virtual ~DatabaseAccessor() {}
 
     /// \brief Retrieve a zone identifier
     ///
@@ -164,8 +164,8 @@ public:
     /// apex), as the DatabaseClient will loop trough the labels itself and
     /// find the most suitable zone.
     ///
-    /// It is not specified if and what implementation of this method may throw,
-    /// so code should expect anything.
+    /// It is not specified if and what implementation of this method may
+    /// throw, so code should expect anything.
     ///
     /// \param name The (fully qualified) domain name of the zone's apex to be
     ///             looked up.
@@ -195,6 +195,8 @@ public:
     ///         or was created by this call).
     virtual int addZone(const std::string& name) = 0;
 
+    virtual void deleteZone(int zone_id) = 0;
+
     /// \brief This holds the internal context of ZoneIterator for databases
     ///
     /// While the ZoneIterator implementation from DatabaseClient does all the
@@ -212,15 +214,15 @@ public:
         /// \brief Destructor
         ///
         /// Virtual destructor, so any descendand class is destroyed correctly.
-        virtual ~IteratorContext() { }
+        virtual ~IteratorContext() {}
 
         /// \brief Function to provide next resource record
         ///
         /// This function should provide data about the next resource record
         /// from the data that is searched. The data is not converted yet.
         ///
-        /// Depending on how the iterator was constructed, there is a difference
-        /// in behaviour; for a 'full zone iterator', created with
+        /// Depending on how the iterator was constructed, there is a
+        /// difference in behaviour; for a 'full zone iterator', created with
         /// getAllRecords(), all COLUMN_COUNT elements of the array are
         /// overwritten.
         /// For a 'name iterator', created with getRecords(), the column

src/lib/datasrc/sqlite3_accessor.cc

@@ -79,7 +79,8 @@ enum StatementID {
     DEL_ZONE_NSEC3_RECORDS = 20,
     DEL_NSEC3_RECORD = 21,
     ADD_ZONE = 22,
-    NUM_STATEMENTS = 23
+    DELETE_ZONE = 23,
+    NUM_STATEMENTS = 24
 };
 
 const char* const text_statements[NUM_STATEMENTS] = {
@@ -165,7 +166,9 @@ const char* const text_statements[NUM_STATEMENTS] = {
     "AND rdtype=?3 AND rdata=?4",
 
     // ADD_ZONE: add a zone to the zones table
-    "INSERT INTO zones (name, rdclass) VALUES (?1, ?2)" // ADD_ZONE
+    "INSERT INTO zones (name, rdclass) VALUES (?1, ?2)", // ADD_ZONE
+    // DELETE_ZONE: delete a zone from the zones table
+    "DELETE FROM zones WHERE id=?1" // DELETE_ZONE
 };
 
 struct SQLite3Parameters {
@@ -643,6 +646,19 @@ SQLite3Accessor::addZone(const std::string& name) {
     return (getzone_result.second);
 }
 
+void
+SQLite3Accessor::deleteZone(int zone_id) {
+    // Transaction should have been started by the caller
+    if (!dbparameters_->in_transaction) {
+        isc_throw(InvalidOperation, "performing deleteZone on SQLite3 "
+                  "data source without transaction");
+    }
+
+    StatementProcessor proc(*dbparameters_, DELETE_ZONE, "delete zone");
+    proc.bindInt(1, zone_id);
+    proc.exec();
+}
+
 namespace {
 
 // Conversion to plain char

src/lib/datasrc/sqlite3_accessor.h

@@ -139,6 +139,8 @@ public:
     /// \return the id of the zone that has been added
     virtual int addZone(const std::string& name);
 
+    virtual void deleteZone(int zone_id);
+
     /// \brief Look up all resource records for a name
     ///
     /// This implements the getRecords() method from DatabaseAccessor

src/lib/datasrc/tests/database_unittest.cc

@@ -279,6 +279,11 @@ public:
                   "This database datasource can't add zones");
     }
 
+    virtual void deleteZone(int) {
+        isc_throw(isc::NotImplemented,
+                  "This database datasource can't delete zones");
+    }
+
     virtual boost::shared_ptr<DatabaseAccessor> clone() {
         // This accessor is stateless, so we can simply return a new instance.
         return (boost::shared_ptr<DatabaseAccessor>(new NopAccessor));

src/lib/datasrc/tests/sqlite3_accessor_unittest.cc

@@ -20,6 +20,8 @@
 
 #include <dns/rrclass.h>
 
+#include <exceptions/exceptions.h>
+
 #include <sqlite3.h>
 
 #include <gtest/gtest.h>
@@ -1615,4 +1617,50 @@ TEST_F(SQLite3Update, addZoneWhileLocked) {
     EXPECT_FALSE(accessor->getZone(new_zone).first);
 }
 
+//
+// Tests for deleteZone() follow.
+//
+TEST_F(SQLite3Update, deleteZone) {
+    const std::pair<bool, int> zone_info(accessor->getZone("example.com."));
+    ASSERT_TRUE(zone_info.first);
+    zone_id = zone_info.second;
+
+    // Calling deleteZone without transaction should fail
+    EXPECT_THROW(accessor->deleteZone(zone_info.first), isc::InvalidOperation);
+
+    // Delete the zone.  Then confirm it, both before and after commit.
+    accessor->startTransaction();
+    accessor->deleteZone(zone_info.second);
+    EXPECT_FALSE(accessor->getZone("example.com.").first);
+    accessor->commit();
+    EXPECT_FALSE(accessor->getZone("example.com.").first);
+
+    // Records are not deleted.
+    std::string data[DatabaseAccessor::COLUMN_COUNT];
+    EXPECT_TRUE(accessor->getRecords("example.com.", zone_id, false)
+                ->getNext(data));
+}
+
+TEST_F(SQLite3Update, deleteZoneWhileLocked) {
+    const std::pair<bool, int> zone_info(accessor->getZone("example.com."));
+    ASSERT_TRUE(zone_info.first);
+    zone_id = zone_info.second;
+
+    // Adding another (not commit yet), it should lock the db
+    const std::string new_zone = "new.example.com.";
+    accessor->startTransaction();
+    zone_id = accessor->addZone(new_zone);
+
+    // deleteZone should throw an exception that it is locked
+    another_accessor->startTransaction();
+    EXPECT_THROW(another_accessor->deleteZone(zone_id), DataSourceError);
+    // Commit should do nothing, but not fail
+    another_accessor->commit();
+
+    accessor->rollback();
+
+    // The zone should still exist.
+    EXPECT_TRUE(accessor->getZone("example.com.").first);
+}
+
 } // end anonymous namespace