NAME
MR::Tarantool::Box - A driver for an efficient Tarantool/Box NoSQL in-memory storage.
SYNOPSIS
my $box = MR::Tarantool::Box->new({
servers => "127.0.0.1:33013",
name => "My Box", # mostly used for debug purposes
spaces => [ {
indexes => [ {
index_name => 'idx1',
keys => [0],
}, {
index_name => 'idx2',
keys => [1,2],
}, ],
space => 1, # space id, as set in Tarantool/Box config
name => "primary", # self-descriptive space-id
format => "QqLlSsCc&$", # pack()-compatible, Qq must be supported by perl itself,
# & stands for byte-string, $ stands for utf8 string.
default_index => 'idx1',
fields => [qw/ id f2 field3 f4 f5 f6 f7 f8 misc_string /], # turn each tuple into hash, field names according to format
}, {
#...
} ],
default_space => "primary",
timeout => 1.0, # seconds
retry => 3,
debug => 9, # output to STDERR some debugging info
raise => 0, # dont raise an exception in case of error
});
my $bool = $box->Insert(1, 2,3, 4,5,6,7,8,"asdf") or die $box->ErrorStr;
my $bool = $box->Insert(2, 2,4, 4,5,6,7,8,"asdf",{space => "primary"}) or die $box->ErrorStr;
my $tuple = $box->Insert(3, 3,3, 4,5,6,7,8,"asdf",{want_inserted_tuple => 1}) or die $box->ErrorStr;
# Select by single-field key
my $tuple = $box->Select(1); # scalar context - scalar result: $tuple
my @tuples = $box->Select(1,2,3); # list context - list result: ($tuple, $tuple, ...)
my $tuples = $box->Select([1,2,3],{space => "primary", use_index => "idx1"}); # arrayref result: [$tuple, $tuple, ...]
# Select by multi-field key
my $tuples = $box->Select([[2,3]],{use_index => "idx2"}); # by full key
my $tuples = $box->Select([[2]] ,{use_index => "idx2"}); # by partial key
my $bool = $box->UpdateMulti(1,[ f4 => add => 3 ]);
my $bool = $box->UpdateMulti(2,[ f4 => add => 3 ],{space => "primary"});
my $tuple = $box->UpdateMulti(3,[ f4 => add => 3 ],{want_updated_tuple => 1});
my $bool = $box->Delete(1);
my $tuple = $box->Delete(2, {want_deleted_tuple => 1});
DESCRIPTION
METHODS
new
my $box = $class->new(\%args);
%args:
- spaces => [ \%space, ... ]
-
%space:
- space => $space_id_uint32
-
Space id as set in Tarantool/Box config.
- name => $space_name_string
-
Self-descriptive space id, which will be mapped into
space
. - format => $format_string
-
pack()
-compatible tuple format string, allowed formats:QqLlSsC(c&$)*
, where&
stands for bytestring,$
stands for "utf8" string.Qq
usable only if perl supports int64 itself. Tuples' fields are packed/unpacked according to thisformat
.*
at the end offormat
enables "LongTuple". - hashify => $coderef
-
Specify a callback to turn each tuple into a good-looking hash. It receives
space
id and resultset as arguments. No return value needed.$coderef = sub { my ($space_id, $resultset) = @_; $_ = { FieldName1 => $_->[0], FieldName2 => $_->[1], ... } for @$resultset; };
- fields => $arrayref
-
Specify an arrayref of fields names according to
format
to turn each tuple into a good-looking hash. Names must begin with[A-Za-z]
. If "LongTuple" enabled, last field will be used to fold tailing fields. - long_fields => $arrayref
-
Specify an arrayref of fields names according to
(xxx)*
to turn tailing fields into a good-looking array of hashes. Names must begin with[A-Za-z]
. Works with "LongTuple" enabled only. - indexes => [ \%index, ... ]
-
%index:
- id => $index_id_uint32
-
Index id as set in Tarantool/Box config within current
space
. If not set, order position inindexes
is theated asid
. - name => $index_name_string
-
Self-descriptive index id, which will be mapped into
index_id
. - keys => [ $field_no_uint32, ... ]
-
Properly ordered arrayref of fields' numbers which are indexed.
- default_index => $default_index_name_string_or_id_uint32
-
Index
id
orname
to be used by default for the currentspace
in select operations. Must be set if there are more than one\%index
es. - primary_key_index => $primary_key_name_string_or_id_uint32
-
Index
id
orname
to be used by default for the currentspace
in update operations. It is set todefault_index
by default.
- default_space => $default_space_name_string_or_id_uint32
-
Space
space
orname
to be used by default. Must be set if there are more than one\%space
s. - timeout => $timeout_fractional_seconds_float || 23
-
A common timeout for network operations.
- select_timeout => $select_timeout_fractional_seconds_float || 2
-
Select queries timeout for network operations. See "select_retry".
- retry => $retry_int || 1
-
A common retries number for network operations.
- select_retry => $select_retry_int || 3
-
Select queries retries number for network operations.
Sometimes we need short timeout for select's and long timeout for critical update's, because in case of timeout we don't know if the update has succeeded. For the same reason we can't retry update operation.
So increasing
timeout
and settingretry => 1
for updates lowers possibility of such situations (but, of course, does not exclude them at all), and guarantees that we dont do the same more then once. - soft_retry => $soft_retry_int || 3
-
A common retries number for Tarantool/Box temporary errors (these marked by 1 in the lowest byte of
error_code
). In that case we know for sure that the request was declined by Tarantool/Box for some reason (a tuple was locked for another update, for example), and we can try it again.This is also limited by
retry
/select_retry
(depending on query type). - retry_delay => $retry_delay_fractional_seconds_float || 1
-
Specify a delay between retries for network operations.
- raise => $raise_bool || 1
-
Should we raise an exceptions? If so, exceptions are raised when no more retries left and all tries failed (with timeout, fatal, or temporary error).
- debug => $debug_level_int || 0
-
Debug level, 0 - print nothing, 9 - print everything
- name => $name
-
A string used for self-description. Mainly used for debugging purposes.
Error
Last error code, or 'fail' for some network reason, oftenly a timeout.
$box->Insert(@tuple) or die sprintf "Error %X", $box->Error; # die "Error 202"
ErrorStr
Last error code and description in a single string.
$box->Insert(@tuple) or die $box->ErrorStr; # die "Error 00000202: Illegal Parameters"
Call
Call a stored procedure. Returns an arrayref of the result tuple(s) upon success.
my $results = $box->Call('stored_procedure_name', \@procedure_params, \%options) or die $box->ErrorStr; # Call failed
my $result_tuple = @$results && $results->[0] or warn "Call succeeded, but returned nothing";
- @procedure_params
-
An array of bytestrings to be passed as is to the procecedure.
- %options
-
- unpack_format
-
Format to unpack the result tuple, the same as
format
option fornew()
Add, Insert, Replace
$box->Add(@tuple) or die $box->ErrorStr; # only store a new tuple
$box->Replace(@tuple, { space => "secondary" }); # only store an existing tuple
$box->Insert(@tuple, { space => "main" }); # store anyway
Insert a @tuple
into the storage into $options{space}
or default_space
space. All of them return true
upon success.
All of them have the same parameters:
- @tuple
-
A tuple to insert. All fields must be defined. All fields will be
pack()
ed according toformat
(see "new") - %options
The difference between them is the behaviour concerning tuple with the same primary key:
Add will succeed if and only if duplicate-key tuple does not exist
Replace will succeed if and only if a duplicate-key tuple exists
Insert will succeed anyway. Duplicate-key tuple will be overwritten
Select
Select tuple(s) from storage
my $key = $id;
my $key = [ $firstname, $lastname ];
my @keys = ($key, ...);
my $tuple = $box->Select($key) or $box->Error && die $box->ErrorStr;
my $tuple = $box->Select($key, \%options) or $box->Error && die $box->ErrorStr;
my @tuples = $box->Select(@keys) or $box->Error && die $box->ErrorStr;
my @tuples = $box->Select(@keys, \%options) or $box->Error && die $box->ErrorStr;
my $tuples = $box->Select(\@keys) or die $box->ErrorStr;
my $tuples = $box->Select(\@keys, \%options) or die $box->ErrorStr;
- $key, @keys, \@keys
-
Specify keys to select. All keys must be defined.
Contextual behaviour:
In scalar context, you can select one
$key
, and the resulting tuple will be returned. Check$box->Error
to see if there was an error or there is just no such key in the storageIn list context, you can select several
@keys
, and the resulting tuples will be returned. Check$box->Error
to see if there was an error or there is just no such keys in the storageIf you select
\@keys
then\@tuples
will be returned upon success.@tuples
will be empty if there are no such keys, and false will be returned in case of error.
Other notes:
If you select using index on multiple fields each
$key
should be given as a key-tuple$key = [ $key_field1, $key_field2, ... ]
.
- %options
-
- space => $space_id_uint32_or_name_string
-
Specify storage (by id or name) space to select from.
- use_index => $index_id_uint32_or_name_string
-
Specify index (by id or name) to use.
- limit => $limit_uint32
-
Max tuples to select. It is set to
MAX_INT32
by default. - raw => $bool
- hash_by => $by
-
Return a hashref of the resultset. If you
hashify
the result set, then$by
must be a field name of the hash you return, otherwise it must be a number of field of the tuple.False
will be returned in case of error.
Delete
Delete tuple from storage. Return false upon error.
my $n_deleted = $box->Delete($key) or die $box->ErrorStr;
my $n_deleted = $box->Delete($key, \%options) or die $box->ErrorStr;
warn "Nothing was deleted" unless int $n_deleted;
my $deleted_tuple_set = $box->Delete($key, { want_deleted_tuples => 1 }) or die $box->ErrorStr;
warn "Nothing was deleted" unless @$deleted_tuple_set;
UpdateMulti
Apply several update operations to a tuple.
my @op = ([ f1 => add => 10 ], [ f1 => and => 0xFF], [ f2 => set => time() ], [ misc_string => cutend => 3 ]);
my $n_updated = $box->UpdateMulti($key, @op) or die $box->ErrorStr;
my $n_updated = $box->UpdateMulti($key, @op, \%options) or die $box->ErrorStr;
warn "Nothing was updated" unless int $n_updated;
my $updated_tuple_set = $box->UpdateMulti($key, @op, { want_result => 1 }) or die $box->ErrorStr;
warn "Nothing was updated" unless @$updated_tuple_set;
Different fields can be updated at one shot. The same field can be updated more than once. All update operations are done atomically. Returns false upon error.
- @op = ([ $field => $op => $value ], ...)
-
- $field
-
Field-to-update number or name (see "fields").
- $op
-
- set
-
Set
$field
to$value
- add, and, xor, or
-
Apply an arithmetic operation to
$field
with argument$value
Currently arithmetic operations are supported only for int32 (4-byte length) fields (and$value
s too) - splice, substr
-
Apply a perl-like splice operation to
$field
. $value = [$OFFSET, $LENGTH, $REPLACE_WITH]. substr is just an alias. - append, prepend
-
Append or prepend
$field
with$value
string. - cutbeg, cutend
-
Cut
$value
bytes from beginning or end of$field
.
- %options
AnyEvent
Insert, UpdateMulti, Select, Delete, Call
methods can be given the following options:
- callback => sub { my ($data, $error) = @_; }
-
Do an async request using AnyEvent.
$data
contains unpacked and processed according to request options data.$error
contains a message string in case of error. Set upraise => 0
to use this option.
"Continuations"
Select
methods can be given the following options:
- return_fh => 1
-
The request does only send operation on network, and returns
{ fh => $IO_Handle, continue => $code }
or false if send operation failed.$code
reads data from network, unpacks, processes according to options and returns it.You should handle timeouts and retries manually (using select() call for example). Usage example:
my $continuation = $box->Select(13,{ return_fh => 1 }); ok $continuation, "select/continuation"; my $rin = ''; vec($rin,$continuation->{fh}->fileno,1) = 1; my $ein = $rin; ok 0 <= select($rin,undef,$ein,2), "select/continuation/select"; my $res = $continuation->{continue}->(); use Data::Dumper; is_deeply $res, [13, 'some_email@test.mail.ru', 1, 2, 3, 4, '123456789'], "select/continuation/result";
LongTuple
If format
given to "new", or unpack_format
given to "Call" ends with a star (*
) long tuple is enabled. Last field or group of fields of format
represent variable-length tail of the tuple. long_fields
option given to "new" will fold the tail into array of hashes.
$box->Insert(1,"2",3);
$box->Insert(3,"2",3,4,5);
$box->Insert(5,"2",3,4,5,6,7);
If we set up
format => "L&CL*",
fields => [qw/ a b c d /], # d is the folding field here
# no long_fields - no folding into hash
we'll get:
$result = $box->Select([1,2,3,4,5]);
$result = [
{ a => 1, b => "2", c => 3, d => [] },
{ a => 3, b => "2", c => 3, d => [4,5] },
{ a => 5, b => "2", c => 3, d => [4,5,6,7] },
];
And if we set up
format => "L&C(LL)*",
fields => [qw/ a b c d /], # d is the folding field here
long_fields => [qw/ d1 d2 /],
we'll get:
$result = [
{ a => 1, b => "2", c => 3, d => [] },
{ a => 3, b => "2", c => 3, d => [{d1=>4, d2=>5}] },
{ a => 5, b => "2", c => 3, d => [{d1=>4, d2=>5}, {d1=>6, d2=>7}] },
];
utf8
Utf8 strings are supported very simply. When pushing any data to tarantool (with any query, read or write), the utf8 flag is set off, so all data is pushed as bytestring. When reading response, for fields marked a dollar sign $
(see "new") (including such in "LongTuple" tail) utf8 flag is set on. That's all. Validity is on your own.
LICENCE AND COPYRIGHT
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
SEE ALSO
1 POD Error
The following errors were encountered while parsing the POD:
- Around line 1470:
You forgot a '=back' before '=head2'