Before the patch there was a race in replication
password configuration. It was possible that a replica
connects to a master with a custom password before
that password is actually set. The replica treated the
error as critical and exited.

But in fact it is not critical. Replica even can
withstand absence of a user and keeps reconnecting.
Wrong password situation arises from the same problem
of non atomic configuration and is fixed the same -
keep reconnect attempts if the password was wrong.

Closes #4550

Closes #4519

@TarantoolBot document
Title: key_def.new() accept both 'field' and 'fieldno'

Before the patch key_def.new() took an index part
array as it is returned in <index_object>.parts: each
part should include 'type', 'fieldno', and what else
.parts element contains.

But it was not possible to create a key_def from an
index definition - the array passed to
<space_object>.create_index() 'parts' argument. Because
key_def.new() didn't recognize 'field' option. That
might be useful, when a key_def is needed on a remote
client, where a space object and its indexes do not
exist. And it would be strange to force a user to
create them just so as he would be able to access

    <net_box connection>.space.<space_name>.
        index.<index_name>.parts

As well as it would be crutchy to make a user manually
replace 'field' with 'fieldno' in its index definition
just to create a key_def.

Additionally, an ability to pass an index definition
to a key_def constructor makes the API more symmetric.

Note, that it still is not 100% symmetric, because a
user can't pass field names to the key_def
constructor. A space is needed for that anyway.

The previous patch introduced a way to set box.cfg options
in a strict order, even on a reconfiguration. It was used to set
listen before replication.
The same order problem existed for replication settings. A user
could do

    box.cfg{
        replication_connect_quorum = 0,
        replication = {...}
    }

and expect, that due to quorum 0 the cfg() will return
immediately. But actually the behaviour was undefined - due to
arbitrary order of keys in a Lua table, replication could be
applied before quorum.

The patch makes all replication settings be applied before
replication.

Follow up #4433
Part of #3760

Before the patch the nil UUID was ignored and a new random one
was generated. This was because internally box treats nil UUID
as its absence.

Now a user will see an explicit message that nil UUID is a
reserved value.

Closes #4282

Added Ubuntu 19.10 Eoan Ermine into CI.

Close #4583

Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

Before this patch RUN_TESTS condition in Dockerfile.staticbuild was
ignored and always was true.

However adding of brackets solves only part of problem. If RUN_TESTS is
empty `sh -c` returns 1 and build fails.

However if we run tests we should fail build if tests are not passed.
Ternary logic was rewritten to fair if-else.

This patch fixes it and allows build tarantool statically without
running tests.

@Totktonada: Fixed .gitlab.mk to pass RUN_TESTS environment variable to
docker build arguments.

Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

In scope of 8fac6972 it was fixed misbehavior while passing floating
point values to integer iterator. Unfortunately, that patch introduced
off-by-one error. Number of constraints (equalities and inequalities)
can not be greater than number of key parts (obviously, each constraint
can be tested against at most one index part). Inequality constraint can
involve only field representing last key part. To get it number of
constraints was used as index. However, since array is 0-based, the last
key part should be calculated as parts[eq_numb - 1]. Before this patch
it was parts[eq_numb].

Closes #4558

If a tarantool instance exits while joining replica is in progress,
the replica joining thread can access already freed data resulting
in a crash. Let's fix this the same way we did for checkpoint thread
- simply cancel the thread forcefully and wait for it to terminate.

Closes #4528

After we started using bundled version of libyaml by default (see commit
47b91e90), we can remove it from
building dependencies for RPM and DEB packages.

Closes #4442

Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

Is_nullable JSON-path indexes used to lose is_nullable property
being defined on a space having format. This patch fixes this
problem.

Closes #4520

Functional index extractor code used to raise an invalid
error message when the user-defined extractor function
returns a scalar instead of a table.

Closes #4553

Wrap throwing lua_newthread in luaT_newthread using luaT_cpcall
to process arising error properly.

Closes #4556

End recovery (which means building secondary indexes) just after
last known log file was read. This allows fast switch to hot standby
instance without any delay for secondary index to be built.
Due to engine_end_recovery carryover, xdir_collect_inprogress,
previously being called from it, is now moved to garbage collector.

Closes #4135

expmask indicated necessity to recompile statement after parameter was
bound: it might turn out that parameter can affect query plan. However,
part of this mechanism has been removed long ago as a SQLite's legacy.
In its current state expmask is likely to be useless and assertions
involving it are obviously unsuitable. This patch completely removes
expmask and related routines.

Closes #4566

Console client's eval() method in case of an error at
reading from a socket was trying to return a variable
declared in a different view scope. Instead, the
error should be raised to drop the connection.

Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

When we handle unix console connection we should setup
eos if only we meet "\set output" command in a stream.
For example there could be "\set language" which should
not affect eos settings.

Closes #4568

Reported-by: Alexander Turenko <alexander.turenko@tarantool.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

This will allow us to reuse this map in other routines
and same time optimize memory allocation a bit.

Part-of #4568

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Reviewed-by: Alexander Turenko <alexander.turenko@tarantool.org>

All user-defined functions feature type of returned value (if it
is not specified during function creation, it is assumed to be
ANY), but currently it is ignored. This patch introduces check
which verifies that returned value is of specified in function's
definition type. There's no attempt at implicit conversion to
specified (target) type - returned value must be literally of
the specified type.

Closes #4387

Start using comprehensive serializer luaL_tofield() to prepare
LUA arguments for UDFs. This allows to support cdata types
returned from Lua function.

Needed for #4387

@TarantoolBot document
Title: UDF returning nil or box.NULL in SQL

Values nil and box.NULL returned by UDF in SQL
both transformed to SQL NULL and are equal.

Example:
tarantool> box.execute("SELECT LUA('return box.NULL') is NULL
                               and LUA('return nil') is NULL")
---
- metadata:
  - name: LUA('return box.NULL') is NULL and LUA('return nil') is NULL
    type: boolean
  rows:
  - [true]
...

This patch introduces handling the situation when UDF returns
too many values. Previously Tarantool used to silently use
the first value returned. Now an error is raised.

Moreover a test coverage is improved also for the situation when
no value is returned.

Needed for #4387

Rows_per_wal option was deprecated because it can be covered by
wal_max_size. In order not to complicate WAL code with that
option's support this commit drops it completely.

In some tests the option was used to create several small xlog
files. Now the same is done via wal_max_size. Where it was
needed, number of rows per wal is estimated as wal_max_size / 50.
Because struct xrow_header size ~= 50 not counting paddings and
body.

Note, file box/configuration.result was deleted here, because it
is a stray result file, and it contained the rows_per_wal option
mentioning. Its test was dropped much earlier in
fdc3d1dd.

Closes #3762

In patch c6bea65f I
added a bug - replication/misc leaves a bad value in
box.cfg.replication. Before that patch the test was
resetting this to empty replication. In my patch I
forgot about that, and left there the value

    {box.cfg.listen, "12345"}

This patch cleans it up.

Follow up #3760

This patch changes OP_Function parameters convention: now a
function's name is passed instead of pointer to the function
object. This allows to normally handle the situation, when UDF
has been deleted to the moment of the VDBE code execution.
In particular case this may happen with CK constraints that
refers to a deleted persistent function.

Closes #4176

Closes #4244

@TarantoolBot document
Title: an ability to disable CK constraints

Now it is possible to disable and enable ck constraints.
All ck constraints are enabled by default when Tarantool is
configured. Ck constraints checks are not performed during
standard recovery, but performed during force_recovery -
all conflicting tuples are skipped in case of ck_constraint
conflict.

To change CK constraint "is_enabled" state, call
-- in LUA
ck_obj:enable(new_state in {true, false})
-- in SQL
ALTER TABLE {TABLE_NAME} {EN, DIS}ABLE CHECK CONSTRAINT {CK_NAME};

Example:
box.space.T6.ck_constraint.ck_unnamed_T6_1:enable(false)
box.space.T6.ck_constraint.ck_unnamed_T6_1
- space_id: 512
  is_enabled: false
  name: ck_unnamed_T6_1
  expr: a < 10
box.space.T6:insert({11})
-- passed
box.execute("ALTER TABLE t6 ENABLE CHECK CONSTRAINT \"ck_unnamed_T6_1\"")
box.space.T6:insert({12})
- error: 'Check constraint failed ''ck_unnamed_T6_1'': a < 10'

Now it is possible to disable and enable ck constraints in LUA.
This option is persistent. All ck constraints are constructed
in enabled state when Tarantool is configured. This ability
may be usefulwhen processed data is verified and constraints
validation is not required. For instance, during casual recovery
process there's no need to provide any checks since data is
assumed to be consistent.

Persisting is_enabled flag is an important feature.
If the option is not stored the following scenario is
possible:
- the option is turned off
- data is changed so that a constraint is violated
- the system is restarted while the option state is lost
- there is no way (even in theory) to discover it and find that
  data is incorrect.

Part of #4244

test_run:wait_upstream() and test_run:wait_downstream() now wait until
an upstream / a downstream appears. This prevents an attempt to index a
nil value when one of those functions are called before a record about a
peer appears in box.info.replication. It was observed on
replication/show_error_on_disconnect test after commit
c6bea65f ('replication: recfg with 0
quorum returns immediately').

Fixes #4563.

The trigger pointer in the sql_trigger structure is a dead code
now, so it could be deleted.

Needed for #4343

Prior to this patch, the auto-increment feature could only be set
in an INTEGER field of PRIMARY KEY if the PRIMARY KEY consisted of
a single field. It was not possible to use this feature if the
PRIMARY KEY consisted of more than one field. This patch defines
two ways to set AUTOINCREMENT for any INTEGER or UNSIGNED field of
PRIMARY KEY.

Closes #4217

@TarantoolBot document
Title: The auto-increment feature for multipart PK
The auto-increment feature can be set to any INTEGER or UNSIGNED
field of PRIMARY KEY using one of two ways:
1) AUTOINCREMENT in column definition:
CREATE TABLE t (i INT, a INT AUTOINCREMENT, PRIMARY KEY (i, a));
CREATE TABLE t (i INT AUTOINCREMENT, a INT, PRIMARY KEY (i, a));
2) AUTOINCREMENT in PRIMARY KEY definition:
CREATE TABLE t (i INT, a INT, PRIMARY KEY (i, a AUTOINCREMENT));
CREATE TABLE t (i INT, a INT, PRIMARY KEY (i AUTOINCREMENT, a));

Replication quorum 0 not only affects orphan status, but also,
according to documentation, makes box.cfg() return immediately
regardless of whether connections to upstreams are established.

It was not so before the patch. What is worse, even with non 0
quorum the instance was blocked on reconfiguration for connect
timeout seconds, if at least one node is not connected.

Now quorum is respected on reconfiguration. On a bootstrap it is
still impossible to return earlier than
replication_connect_timeout, because nodes need to choose some
cluster settings. Too early start would make it impossible -
cluster's participants will just start and choose different
cluster UUIDs.

Closes #3760

A successfully fetched remote instance ballot isn't updated during
bootstrap procedure. This leads to a case when different instances
choose different masters as their bootstrap leaders.

Imagine such a situation.
You start instance A without replication set up. Instance A successfully
bootstraps.
You also have instances B and C both with replication set up to {A, B,
C} and replication_connect_quorum set to 3
You first start instance B. It doesn't proceed to choosing a leader
until one of the events happens: either the replication_connect_timeout
runs out, or instance C is up and starts listening on its port.
B has established connection to A and fetched its ballot, with some
vclock, say, {1: 1}.
B retries connection to C every replication_timeout seconds.
Then you start instance C. Instance C succeeds in connecting to A and B
right away and bootstraps from instance A. Instance A registers C in its
_cluster table. This registration is replicated to instance C.
Meanwhile, instance C is trying to sync with quorum instances (which is
3), and stays in orphan mode.
Now replication_timeout on instance B finally runs out. It retries a
previously unsuccessful connection to C and succeeds. C sends its ballot
to B with vclock = {1: 2, 2:0} (in our example), since it has already
incremented it after _cluster registration.
B sees that C has a greater vclock than A, and chooses to bootstrap from
C instead of A. C is orphan and rejects B's attempt to join. B dies.

To fix such ungentlemanlike behaviour of C, we should at least include
loading status in ballot and prefer fully bootstrapped instances to the
ones still syncing with other replicas.
We also need to use a separate flag instead of ballot's already existent
is_ro, since we still want to prefer loading instances over the ones
explicitly configured to be read-only.

Closes #4527

During rework of the console lua mode series
the declaration of variable has been lost and
this cause test case for remote unix console
connection to fail.

Fixes issue from c358398c

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

To be consistent in naming scheme, for example
we already have parse_operators.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

The other modules would be able to find out which eos marker
is currently active. For example when reading replies from
remote server via text based console protocol.

@TarantoolBot document
Title: > require('console').eos()

Returns a string with currently active end of string marker.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

If we change output mode on remote machine via
text-based session

 node a (server)
 ------
 require('console').listen('unix/:/tmp/X.sock')
 ...

 node b (client)
 ------
 require('console').connect('unix/:/tmp/X.sock')
 connected to unix/:/tmp/X.sock
 ...
 unix/:/tmp/X.sock> \set output lua

the client get stuck forever, it is because the text
wire protocol waits for yaml eos terminator which of
course never hit the peer, because lua mode uses own
one.

Thus to fix this problem we have to preprocess the text
we're passing to the server, just like we do in local
console. So we reuse command parsing code and remember
current output terminator in text_connection_mt instance.

Another problem is that named default output mode. There
could be a mixed environment where server operates in
default lua mode but client connects with yaml mode. To
break a tie we yield "\set output" command with current
output mode when establishing a connection. Since the
output format is per-session bound this doesn't affect
any other connections on a server.

Part-of #3834

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

We will need to parse and verify "\set" commands
in remote console text-wire protocol thus to not
duplicate the code lets factor helper out for
reuse sake.

Part-of #3834

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

This will help us to distinguish end of string/stream
in text protocols (such as remote console connection).

Note that we start printing ";" terminator for every
lua output. Actually current yaml output does the
same but inside console.c module.

And since lua output is yet a new feature in stabilization
phase we're safe to make such changes without breaking api.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

This allows lua to not create them every call since
they are constant speeding up processing a bit.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

Sole symbols (such as box.NULL) are not processed
by serpent "custom" symbols feature, since they
are not in table.

Thus we should process them separately. Without it
we have

 > require('console').set_default_output("lua,block")
 > ;
 > box.NULL
 > "cdata<void %*>: NULL";

instead of

 > box.NULL
 > box.NULL;

as it should be.

Part-of #3834

Reviewed-by: Konstantin Osipov <kostja.osipov@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>