This one is greatly inspired by "MINOR: server: change adm_st_chg_cause storage type".
While looking at current srv_op_st_chg_cause usage, it was clear that
the struct needed some cleanup since some leftovers from asynchronous server
state change updates were left behind and resulted in some useless code
duplication, and making the whole thing harder to maintain.
Two observations were made:
- by tracking down srv_set_{running, stopped, stopping} usage,
we can see that the <reason> argument is always a fixed statically
allocated string.
- check-related state change context (duration, status, code...) is
not used anymore since srv_append_status() directly extracts the
values from the server->check. This is pure legacy from when
the state changes were applied asynchronously.
To prevent code duplication, useless string copies and make the reason/cause
more exportable, we store it as an enum now, and we provide
srv_op_st_chg_cause() function to fetch the related description string.
HEALTH and AGENT causes (check related) are now explicitly identified to
make consumers like srv_append_op_chg_cause() able to fetch checks info
from the server itself if they need to.
Now that event_hdl api is properly implemented in hlua, we may add the
per-server event subscription in addition to the global event
subscription.
Per-server subscription allows to be notified for events related to
single server. It is useful to track a server UP/DOWN and DEL events.
It works exactly like core.event_sub() except that the subscription
will be performed within the server dedicated subscription list instead
of the global one.
The callback function will only be called for server events affecting
the server from which the subscription was performed.
Regarding the implementation, it is pretty trivial at this point, we add
more doc than code this time.
Usage examples have been added to the (lua) documentation.
Now that the event handler API is pretty mature, we can expose it in
the lua API.
Introducing the core.event_sub(<event_types>, <cb>) lua function that
takes an array of event types <event_types> as well as a callback
function <cb> as argument.
The function returns a subscription <sub> on success.
Subscription <sub> allows you to manage the subscription from anywhere
in the script.
To this day only the sub->unsub method is implemented.
The following event types are currently supported:
- "SERVER_ADD": when a server is added
- "SERVER_DEL": when a server is removed from haproxy
- "SERVER_DOWN": server states goes from up to down
- "SERVER_UP": server states goes from down to up
As for the <cb> function: it will be called when one of the registered
event types occur. The function will be called with 3 arguments:
cb(<event>,<data>,<sub>)
<event>: event type (string) that triggered the function.
(could be any of the types used in <event_types> when registering
the subscription)
<data>: data associated with the event (specific to each event family).
For "SERVER_" family events, server details such as server name/id/proxy
will be provided.
If the server still exists (not yet deleted), a reference to the live
server is provided to spare you from an additionnal lookup if you need
to have direct access to the server from lua.
<sub> refers to the subscription. In case you need to manage it from
within an event handler.
(It refers to the same subscription that the one returned from
core.event_sub())
Subscriptions are per-thread: the thread that will be handling the
event is the one who performed the subscription using
core.event_sub() function.
Each thread treats events sequentially, it means that if you have,
let's say SERVER_UP, then SERVER_DOWN in a short timelapse, then your
cb function will first be called with SERVER_UP, and once you're done
handling the event, your function will be called again with SERVER_DOWN.
This is to ensure event consitency when it comes to logging / triggering
logic from lua.
Your lua cb function may yield if needed, but you're pleased to process
the event as fast as possible to prevent the event queue from growing up
To prevent abuses, if the event queue for the current subscription goes
over 100 unconsumed events, the subscription will pause itself
automatically for as long as it takes for your handler to catch up.
This would lead to events being missed, so a warning will be emitted in
the logs to inform you about that. This is not something you want to let
happen too often, it may indicate that you subscribed to an event that
is occurring too frequently or/and that your callback function is too
slow to keep up the pace and you should review it.
If you want to do some parallel processing because your callback
functions are slow: you might want to create subtasks from lua using
core.register_task() from within your callback function to perform the
heavy job in a dedicated task and allow remaining events to be processed
more quickly.
Please check the lua documentation for more information.
Server revision ID was recently added to haproxy with 61e3894
("MINOR: server: add srv->rid (revision id) value")
Let's add it to the hlua server class.
Since ("MINOR: hlua_fcn: alternative to old proxy and server attributes"):
- s->name(), s->puid() are superseded by s->get_name() and s->get_puid()
- px->name(), px->uuid() are superseded by px->get_name() and
px->get_uuid()
And considering this is now the proper way to retrieve proxy name/uuid
and server name/puid from lua:
We're now removing such legacy attributes, but for retro-compatibility
purposes we will be emulating them and warning the user for some time
before completely dropping their support.
To do this, we first remove old legacy code.
Then we move server and proxy methods out of the metatable to allow
direct elements access without systematically involving the "__index"
metamethod.
This allows us to involve the "__index" metamethod only when the requested
key is missing from the table.
Then we define relevant hlua_proxy_index and hlua_server_index functions
that will be used as the "__index" metamethod to respectively handle
"name, uuid" (proxy) or "name, puid" (server) keys, in which case we
warn the user about the need to use the new getter function instead the
legacy attribute (to prepare for the potential upcoming removal), and we
call the getter function to return the value as if the getter function
was directly called from the script.
Note: Using the legacy variables instead of the getter functions results
in a slight overhead due to the "__index" metamethod indirection, thus
it is recommended to switch to the getter functions right away.
With this commit we're also adding a deprecation notice about legacy
attributes.
This patch proposes to enumerate servers using internal HAProxy list.
Also, remove the flag SRV_F_NON_PURGEABLE which makes the server non
purgeable each time Lua uses the server.
Removing reg-tests/cli_delete_server_lua.vtc since this test is no
longer relevant (we don't set the SRV_F_NON_PURGEABLE flag anymore)
and we already have a more generic test:
reg-tests/server/cli_delete_server.vtc
Co-authored-by: Aurelien DARRAGON <adarragon@haproxy.com>
This patch adds new lua methods:
- "Proxy.get_uuid()"
- "Proxy.get_name()"
- "Server.get_puid()"
- "Server.get_name()"
These methods will be equivalent to their old analog Proxy.{uuid,name}
and Server.{puid,name} attributes, but this will be the new preferred
way to fetch such infos as it duplicates memory only when necessary and
thus reduce the overall lua Server/Proxy objects memory footprint.
Legacy attributes (now superseded by the explicit getters) are expected
to be removed some day.
Co-authored-by: Aurelien DARRAGON <adarragon@haproxy.com>
When HAproxy is loaded with a lot of frontends/backends (tested with 300k),
it is slow to start and it uses a lot of memory just for indexing backends
in the lua tables.
This patch uses the internal frontend/backend index of HAProxy in place of
lua table.
HAProxy startup is now quicker as each frontend/backend object is created
on demand and not at init.
This has to come with some cost: the execution of Lua will be a little bit
slower.
Two lua init function seems to return something useful, but it
is not the case. The function "hlua_concat_init" seems to return
a failure status, but the function never fails. The function
"hlua_fcn_reg_core_fcn" seems to return a number of elements in
the stack, but it is not the case.
Right now a spinlock is used, but most accesses are for reads, so let's
switch the lock to an rwlock and switch all accesses to exclusive locks
for now. There should be no visible difference at this point.
There was a race involving hlua_proxy_* functions
and some proxy management functions.
pause_proxy() and resume_proxy() can be used directly from lua code,
but that could lead to some race as lua code didn't make sure PROXY_LOCK
was owned before calling the proxy functions.
This patch makes sure it won't happen again elsewhere in the code
by locking PROXY_LOCK directly in resume and pause proxy functions
so that it's not the caller's responsibility anymore.
(based on stop_proxy() behavior that was already safe prior to the patch)
This should be backported to stable series.
Note that the API will likely differ < 2.4
Found with -Wmissing-prototypes:
src/hlua_fcn.c:53:5: fatal error: no previous prototype for function 'hlua_checkboolean' [-Wmissing-prototypes]
int hlua_checkboolean(lua_State *L, int index)
^
src/hlua_fcn.c:53:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
int hlua_checkboolean(lua_State *L, int index)
^
static
1 error generated.
Since internal proxies are now in the global proxy list, they are now
reachable from core.proxies, core.backends, core.frontends.
This patch fixes the issue by checking the PR_CAP_INT flag before
exposing them in lua, so the user can't have access to them.
This patch must be backported in 2.5.
backend.c, all muxes, backend.c started manipulating ebmb_nodes with
the introduction of idle conns but the types were inherited through
other includes. Let's add ebmbtree.h there.
Currently the stats filling function knows nothing about the caller's
needs, so let's pass the STAT_* flags so that it can adapt to the
requester's constraints.
hlua_pushstrippedstring() function strips leading and trailing LWS
characters. But the result length it too short by 1 byte. Thus the last
non-LWS character is stripped. Note that a string containing only LWS
characters resulting to a stipped string with an invalid length (-1). This
leads to a lua runtime error.
This bug was reported in the issue #1155. It must be backported as far as
1.7.
Some static functions are now exported and renamed to follow the same
pattern of other exported functions. Here is the list :
* update_server_fqdn: Renamed to srv_update_fqdn and exported
* update_server_check_addr_port: renamed to srv_update_check_addr_port and exported
* update_server_agent_addr_port: renamed to srv_update_agent_addr_port and exported
* update_server_addr: renamed to srv_update_addr
* update_server_addr_potr: renamed to srv_update_addr_port
* srv_prepare_for_resolution: exported
This change is mandatory to move all functions dealing with the server-state
files in a separate file.
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to add support for listen stats in
prometheus.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
This patch follows what has already been done on frontend and backend
side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the server.
A few things to note though:
- state require prior calculation, so I moved that to a sort of helper
`stats_fill_be_stats_computestate`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
This patch follows what has already been done on frontend side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the backend
A few things to note though:
- status and uweight field requires prior compute, so I moved that to a
sort of helper `stats_fill_be_stats_computesrv`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Lua requires LLONG_MAX defined with __USE_ISOC99 which is set by
_GNU_SOURCE, not necessarely defined by default on old compiler/glibc.
$ make V=1 TARGET=linux-glibc-legacy USE_THREAD= USE_ACCEPT4= USE_PCRE=1 USE_OPENSSL=1 USE_ZLIB=1 USE_LUA=1
..
cc -Iinclude -O2 -g -Wall -Wextra -Wdeclaration-after-statement -fwrapv -Wno-strict-aliasing -Wno-unused-label -Wno-sign-compare -Wno-unused-parameter -Wno-missing-field-initializers -DUSE_EPOLL -DUSE_NETFILTER -DUSE_PCRE -DUSE_POLL -DUSE_TPROXY -DUSE_LINUX_TPROXY -DUSE_LINUX_SPLICE -DUSE_LIBCRYPT -DUSE_CRYPT_H -DUSE_GETADDRINFO -DUSE_OPENSSL -DUSE_LUA -DUSE_FUTEX -DUSE_ZLIB -DUSE_CPU_AFFINITY -DUSE_DL -DUSE_RT -DUSE_PRCTL -DUSE_THREAD_DUMP -I/usr/include/openssl101e/ -DUSE_PCRE -I/usr/include -DCONFIG_HAPROXY_VERSION=\"2.4-dev5-73246d-83\" -DCONFIG_HAPROXY_DATE=\"2021/01/21\" -c -o src/hlua.o src/hlua.c
In file included from /usr/local/include/lua.h:15,
from /usr/local/include/lauxlib.h:15,
from src/hlua.c:16:
/usr/local/include/luaconf.h:581:2: error: #error "Compiler does not support 'long long'. Use option '-DLUA_32BITS' or '-DLUA_C89_NUMBERS' (see file 'luaconf.h' for details)"
..
cc -Iinclude -O2 -g -Wall -Wextra -Wdeclaration-after-statement -fwrapv -Wno-strict-aliasing -Wno-unused-label -Wno-sign-compare -Wno-unused-parameter -Wno-missing-field-initializers -DUSE_EPOLL -DUSE_NETFILTER -DUSE_PCRE -DUSE_POLL -DUSE_TPROXY -DUSE_LINUX_TPROXY -DUSE_LINUX_SPLICE -DUSE_LIBCRYPT -DUSE_CRYPT_H -DUSE_GETADDRINFO -DUSE_OPENSSL -DUSE_LUA -DUSE_FUTEX -DUSE_ZLIB -DUSE_CPU_AFFINITY -DUSE_DL -DUSE_RT -DUSE_PRCTL -DUSE_THREAD_DUMP -I/usr/include/openssl101e/ -DUSE_PCRE -I/usr/include -DCONFIG_HAPROXY_VERSION=\"2.4-dev5-73246d-83\" -DCONFIG_HAPROXY_DATE=\"2021/01/21\" -c -o src/hlua_fcn.o src/hlua_fcn.c
In file included from /usr/local/include/lua.h:15,
from /usr/local/include/lauxlib.h:15,
from src/hlua_fcn.c:17:
/usr/local/include/luaconf.h:581:2: error: #error "Compiler does not support 'long long'. Use option '-DLUA_32BITS' or '-DLUA_C89_NUMBERS' (see file 'luaconf.h' for details)"
..
Cc: Thierry Fournier <tfournier@arpalert.org>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the frontend.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
Most of the files dealing with error reports have to include log.h in order
to access ha_alert(), ha_warning() etc. But while these functions don't
depend on anything, log.h depends on a lot of stuff because it deals with
log-formats and samples. As a result it's impossible not to embark long
dependencies when using ha_warning() or qfprintf().
This patch moves these low-level functions to errors.h, which already
defines the error codes used at the same places. About half of the users
of log.h could be adjusted, sometimes revealing other issues such as
missing tools.h. Interestingly the total preprocessed size shrunk by
4%.
extern struct dict server_name_dict was moved from the type file to the
main file. A handful of inlined functions were moved at the bottom of
the file. Call places were updated to use server-t.h when relevant, or
to simply drop the entry when not needed.
This one is particularly difficult to split because it provides all the
functions used to manipulate a proxy state and to retrieve names or IDs
for error reporting, and as such, it was included in 73 files (down to
68 after cleanup). It would deserve a small cleanup though the cut points
are not obvious at the moment given the number of structs involved in
the struct proxy itself.
The current state of the logging is a real mess. The main problem is
that almost all files include log.h just in order to have access to
the alert/warning functions like ha_alert() etc, and don't care about
logs. But log.h also deals with real logging as well as log-format and
depends on stream.h and various other things. As such it forces a few
heavy files like stream.h to be loaded early and to hide missing
dependencies depending where it's loaded. Among the missing ones is
syslog.h which was often automatically included resulting in no less
than 3 users missing it.
Among 76 users, only 5 could be removed, and probably 70 don't need the
full set of dependencies.
A good approach would consist in splitting that file in 3 parts:
- one for error output ("errors" ?).
- one for log_format processing
- and one for actual logging.
Almost no change except moving the cli_kw struct definition after the
defines. Almost all users had both types&proto included, which is not
surprizing since this code is old and it used to be the norm a decade
ago. These places were cleaned.
Just some minor reordering, and the usual cleanup of call places for
those which didn't need it. We don't include the whole tools.h into
stats-t anymore but just tools-t.h.
Initially it looked like this could have been placed into auth.h or
stats.h but it's not the case as it's what makes the link between them
and the HTTP layer. However the file needed to be split in two. Quite
a number of call places were dropped because these were mostly leftovers
from the early days where the stats and cli were packed together.
The stktable_types[] array declaration was moved to the main file as
it had nothing to do in the types. A few declarations were reordered
in the types file so that defines were before the structs. Thread-t
was added since there are a few __decl_thread(). The loss of peers.h
revealed that cfgparse-listen needed it.
So the enums and structs were placed into http-t.h and the functions
into http.h. This revealed that several files were dependeng on http.h
but not including it, as it was silently inherited via other files.
Regex are essentially included for myregex_t but it turns out that
several of the C files didn't include it directly, relying on the
one included by their own .h. This has been cleanly addressed so
that only the type is included by H files which need it, and adding
the missing includes for the other ones.
This one is included almost everywhere and used to rely on a few other
.h that are not needed (unistd, stdlib, standard.h). It could possibly
make sense to split it into multiple parts to distinguish operations
performed on timers and the internal time accounting, but at this point
it does not appear much important.
In hlua_stktable_lookup(), the key length is never set so all
stktable:lookup("key") calls return nil from lua.
This patch must be backported as far as 1.9.
[Cf: I slightly updated the patch to use lua_tolstring() instead of
luaL_checkstring() + strlen()]
The issue can easily be reproduced with "stick on" statement
backend BE_NAME
stick-table type ip size 1k
stick on src
and calling dump() method on BE_NAME stick table from Lua
Before the fix, HAProxy would return 500 and log something like
the following:
runtime error: attempt to index a string value from [C] method 'dump'
Where one would expect a Lua table like this:
{
["IP_ADDR"] = {
["server_id"] = 1,
["server_name"] = "srv1"
}
}
This patch needs to backported to 1.9 and later releases.
For complex stick tables with many entries/columns, it can be beneficial
to filter using multiple criteria. The maximum number of filter entries
can be controlled by defining STKTABLE_FILTER_LEN during build time.
This patch can be backported to older releases.
Several times some users have expressed the non-intuitive aspect of some
of our stat/info metrics and suggested to add some help. This patch
replaces the char* arrays with an array of name_desc so that we now have
some reserved room to store a description with each stat or info field.
These descriptions are currently empty and not reported yet.
We used to rely on some config flags defined in uri_auth.h set during
parsing, and another set of STAT_* flags defined in stats.h set at run
time, with a somewhat gray area between the two sets. This is confusing
in the stats code as both are called "flags" in various functions and
it's quite hard to know which one describes what.
This patch cleans this up by replacing all ST_* by a newly assigned
value from the STAT_* set so that we can now use unified flags to
describe both the configuration and the current state. There is no
functional change at all.
Now we atomically allocate the my_regex struct within function
regex_comp() and compile the regex or free both in case of failure. The
pointer to the allocated my_regex struct is returned directly. The
my_regex* argument to regex_comp() is removed.
Function regex_free() was modified so that it systematically frees the
my_regex entry. The function does nothing when called with a NULL as
argument (like free()). It will avoid existing risk of not properly
freeing the initialized area.
Other structures are also updated in order to be compatible (the ones
related to Lua and action rules).
This patch adds the support for the "table" line parsing in "peers" sections
to declare stick-table in such sections. This also prevents the user from having
to declare dummy backends sections with a unique stick-table inside.
Even if still supported, this usage will become deprecated.
To do so, the ->table member of proxy struct which is a stktable struct is replaced
by a pointer to a stktable struct allocated at parsing time in src/cfgparse-listen.c
for the dummy stick-table backends and in src/cfgparse.c for "peers" sections.
This has an impact on the code for stick-table sample converters and on the stickiness
rules parsers which first store the name of the dummy before resolving the rules.
This patch replaces proxy_tbl_by_name() calls by stktable_find_by_name() calls
to lookup for stick-tables stored in "stktable_by_name" ebtree at parsing time.
There is only one remaining place where proxy_tbl_by_name() is used: src/hlua.c.
At several places in the code we relied on the fact that ->size member of stick-table
was equal to zero to consider the stick-table was present by not configured,
this do not make sense anymore as ->table member of struct proxyis fow now on a pointer.
These tests are replaced by a test on ->table value itself.
In "peers" section we do not have to temporary store the name of the section the
stick-table are attached to because this name is obviously already known just after
having entered this "peers" section.
About the CLI stick-table I/O handler, the pointer to proxy struct is replaced by
a pointer to a stktable struct.
