The CLI's "prompt" command toggles two distinct things:
- displaying or hiding the prompt at the beginning of the line
- single-command vs interactive mode
These are two independent concepts and the prompt mode doesn't
always cope well with tools that would like to upload data without
having to read the prompt on return. Also, the master command line
works in interactive mode by default with no prompt, which is not
consistent (and not convenient for tools). So let's start by splitting
the bit in two, and have a new APPCTX_CLI_ST1_INTER flag dedicated
to the interactive mode. For now the "prompt" command alone continues
to toggle the two at once.
There are several fields in the appctx structure only used by the CLI. To
make things cleaner, all these fields are now placed in a dedicated context
inside the appctx structure. The final goal is to move it in the service
context and add an API for cli commands to get a command coontext inside the
cli context.
CLI_ST_GETREQ state was renamed into CLI_ST_PARSE_CMDLINE and CLI_ST_PARSEREQ
into CLI_ST_PROCESS_CMDLINE to reflect the real action performed in these
states.
The CLI applet is now using its own snd_buf callback function. Instead of
copying as most output data as possible, only one command is copied at a
time.
To do so, a new state CLI_ST_PARSEREQ is added for the CLI applet. In this
state, the CLI I/O handle knows a full command was copied into its input
buffer and it must parse this command to evaluate it.
The issue was decribed in commit "BUG/MEDIUM: cli: Warn if pipelined commands
are delimited by a \n". In non-interactive mode, it was possible to use a
newline character as delimiter for pipelined commands. As a consequence, it was
possible to stop commands processing on the middle.
With the above commit, a warning is emitted to notify users. With this one,
we restore the expected behavior, as documented in the management guide.
Only the first line of commands is parsed. This commit will not be
backported to avoid breaking changes on stable versions.
This commit has of course some visible effects. All script using a newline
character as delimiter to pipeline commands in non-interactive mode will
stop working. Only the first command will be evaluated, all others will be
ignored. Pipelined commands MUST now be separated by a semi-colon.
But there is a more subtle and probably more annoying change. It is no
longer possible to pipeline commands with a payload ! A command with a
payload will always be the last one evaluated because it must be finished by
a newline (eventually preceeded by a custom pattern).
It is really annoying to introduce such breaking change. But, on the long
term, it is mandatory. The 2.8 will be the last LST version supporting the
old behavior (with some warning however). This will let 4 years to users to
adapt their scripts.
No backport needed.
This was broken since commit 0011c25144 ("BUG/MINOR: cli: avoid O(bufsize)
parsing cost on pipelined commands"). It is not really a bug fix but it is
labelled as is to make it more visible.
Before, a full line was first retrieved from the request buffer before
extracting the first command to eval it. Now, only one command is retrieved.
But we rely on the request buffer state to interrupt processing in
non-interactive mode. After a command processing, if output of the request
buffer is empty, we leave. Before the above commit, this was not a problem.
But since then, it is obviously a bad statement. First because some input
data may still be there. It is not true today, but it might change. Then,
there is no warranty to receive all commands in same time. For small list of
commands, it will be most of time the case, but it is a dangerous
assumption. For long list of commands, it is almost always false.
To be an issue, commands must be chunked exactly between two commands. But
in this case, remaining commands are skipped. A good way to reproduce the
issue is to wait a bit between two commands, for instance:
(printf "show info;"; sleep 2; printf "show stat\n") | socat ...
In fact, to properly fix the issue, we should exit on the first command
finished by a newline. Indeed, as stated in the documentation, in
non-interactive mode, a single line is processed. To pipeline commands,
commands must be separated by a semi-colon. Unfortunately, the above commit
introduced another change. It is possible to pipeline commands delimited by
a newline. It was pushed 2 years ago and backported to all stable versions.
Several scripts may rely on this behavior.
So, on stable version, the bug will not be fixed. However a warning will be
emitted to notify users their scripts don't respect the documentation and
they must adapt it. Mainly because the cli behavior on this point will be
changed in 3.0 to stick to the doc. This warning will only be emitted once
over the whole worker process life. Idea is to not flood the logs with the
same warning for every offending commands.
This commit should probably be backported to all stable versions. But with
some cautions because the CLI was often modified.
The "wait" command now supports a condition, "srv-unused", which waits
for the designated server to become totally unused, indicating that it
is removable. Upon each wakeup it calls srv_check_for_deletion() to
verify if conditions are met, if not if it's recoverable, or if it's
not recoverable, and proceeds according to this, never waiting for a
final decision longer than the configured delay.
The purpose is to make it possible to remove servers from the CLI after
waiting for their sessions to be terminated:
$ socat -t5 /path/to/socket - <<< "
disable server px/srv1
shutdown sessions server px/srv1
wait 2s srv-unused px/srv1
del server px/srv1"
Or even wait for connections to terminate themselves:
$ socat -t70 /path/to/socket - <<< "
disable server px/srv1
wait 1m srv-unused px/srv1
del server px/srv1"
Conditions will need to have context, arguments etc from the command line.
Since these will vary with time (otherwise we wouldn't wait), let's just
pass them as text (possibly pre-processed). We're starting with 4 strings
that are expected to be allocated by strdup() and are always sent to free()
upon release.
Since we'll support waiting for an action to succeed or permanently
fail, we need the ability to return an unrecoverable failure. Let's
add CLI_WAIT_ERR_FAIL for this. A static error message may be placed
into ctx->msg to report to the user why the failure is unrecoverable.
This allows to insert delays between commands, i.e. to collect a same
set of metrics at a fixed interval. E.g:
$ socat -t20 /path/to/socket <<< "show activity; wait 10s; show activity"
The goal will be to extend the feature to optionally support waiting on
certain conditions. For this reason the struct definitions and enums were
placed into cli-t.h.
"set severity-output" is one of these command that changes the appctx
state so the next commands are affected.
Unfortunately the master CLI works with pipelining and server close
mode, which means the connection between the master and the worker is
closed after each response, so for the next command this is a new appctx
state.
To fix the problem, 2 new flags are added ACCESS_MCLI_SEVERITY_STR and
ACCESS_MCLI_SEVERITY_NB which are used to prefix each command sent to
the worker with the right "set severity-output" command.
This patch fixes issue #2350.
It could be backported as far as 2.6.
Entering "prompt timed" toggles reporting of the process' uptime in
the prompt, which will report days, hours, minutes and seconds since
it was started. As discussed with Tim in issue #2145, this can be
convenient to roughly estimate the time between two outputs, as well
as detecting that a process failed to be reloaded for example.
CLI 'add server' handler relies on usermsgs_ctx to display errors in
internal function on CLI output. This may be also extended to other
handlers.
However, to not clutter stderr from another contextes, usermsgs_ctx must
be resetted when it is not needed anymore. This operation cannot be
conducted in the CLI parse handler as display is conducted after it.
To achieve this, define new CLI states CLI_ST_PRINT_UMSG /
CLI_ST_PRINT_UMSGERR. Their principles is nearly identical to states for
dynamic messages printing.
Rename CLI_ST_PRINT_FREE to CLI_ST_PRINT_DYNERR.
Most notably, this highlights that this is reserved to error printing.
This is done to ensure consistency between CLI_ST_PRINT/CLI_ST_PRINT_DYN
and CLI_ST_PRINT_ERR/CLI_ST_PRINT_DYNERR. The name is also consistent
with the function cli_dynerr() which activates it.
Now that the CLI's print context is alone in the appctx, it's possible
to refine the appctx's ctx layout so that the cli part matches exactly
a regular svcctx, and as such move the CLI context into an svcctx like
other applets. External code will still build and work because the
struct cli perfectly maps onto the struct cli_print_ctx that's located
into svc.storage. This is of course only to make a smooth transition
during 2.6 and will disappear immediately after.
A tiny change had to be applied to the opentracing addon which performs
direct accesses to the CLI's err pointer in its own print function. The
rest uses the standard cli_print_* which were the only ones that needed
a small change.
The whole "ctx.cli" struct could be tagged as deprecated so that any
possibly existing external code that relies on it will get build
warnings, and the comments in the struct are pretty clear about the
way to fix it, and the lack of future of this old API.
"mcli-debug-mode on" enables every command that were meant for a worker,
on the CLI of the master. Which mean you can issue, "show fd", show
stat" in order to debug the MASTER proxy.
You can also combine it with "expert-mode on" or "experimental-mode on"
to access to more commands.
It's still very difficult to find all commands starting with a given
keyword like "set", "show" etc. Let's sort the lines by usage message,
this is much more convenient.
Entering "show tls" would still emit 35 entries. By measuring the distance
between all unknown words and the candidates, we can sort them and pick the
10 most likely candidates. This works reasonably well, as now "show tls"
only proposes "show tls-keys", "show threads", "show pools" and "show tasks".
If the distance is still too high or if a word is missing, the whole
prefix list continues to be dumped, thus "show" alone will still report
the entire list of commands beginning with "show".
It's still impossible to skip a word, for example "show conn" will not
propose "show servers conn" because the distance is calculated for each
word individually. Some changes to the distance calculation to support
updating an existing map could easily address this. But this is already
a great improvement.
It was mentioned that ACCESS_MASTER_ONLY as for workers only instead of
master-only. And it wasn't clear that all ACCESS_* would belong to the
same thing.
This function will be useful to check if the keyword is already registered.
Also add a define for the max number of args.
This will be needed by a next patch to fix a bug and will have to be
backported.
There are list definitions everywhere in the code, let's drop the need
for including list-t.h to declare them. The rest of the list manipulation
is huge however and not needed everywhere so using the list walking macros
still requires to include list.h.
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.
