Lire::DlfStream(3) Interface to DLF data stream

SYNOPSIS


use Lire::DlfStore;
my $store = Lire::DlfStore->open( "mystore" );
my $dlf_stream = $store->open_dlf_stream( "www", "r" );
print "Data begins on ", scalar localtime $dlf_stream->start_time(), "\n";
print "Data ends on ", scalar localtime $dlf_stream->end_time(), "\n";
while ( my $dlf = $dlf_stream->read_dlf() ) {
...
}

DESCRIPTION

This object encapsulates DLF stream.

name

Returns the schema's name of the DlfStream.

mode()

Returns the mode in which the DlfStream was opened.

sort_spec()

Returns the sort specification that is set on the stream.

close()

This method should be called when the Lire::DlfStream isn't needed anymore, otherwise the same DlfStream cannot be opened until then.

nrecords()

Returs the number of DLF records in the stream.

start_time()

Returns the timestamp of the oldest DLF record in the stream in seconds since the epoch.

end_time()

Returns the timestamp of the newest DLF record in the stream in seconds since the epoch.

read_dlf()

Returns an hash reference containing the next DLF record in the stream. It returns undef once the end of the stream is reached.

This method will throw an exception if the DlfStream isn't open in 'r' mode or if there is an error reading the DLF record.

read_dlf_aref()

Returns the next DLF record in the stream as an array reference. The fields are in the order specified by the schema.

This method will throw an exception if the DlfStream isn't open in 'r' mode or if there is an error reading the DLF record.

write_dlf( $dlf, [ $link_ids ] )

Writes the fields contained in the hash ref $dlf to the DLF stream.

This method will throw an exception if there is an error writing the DLF record or if the stream isn't opened in 'w' mode.

The $link_ids parameter is used when the stream's schema is a Lire::DerivedSchema. It should be an array reference containing the DLF ids of the records which are linked to this record.

clean( [ $time ] )

This method will remove all DLF records older than $time. It $time is omitted, all Dlf records will be removed.