More Complete List of CUPS printer-state-reasons - cups

In RFC8011 p.152 there is a common list of state-reasons that a printer can have. In my testing, this list seems to be very incomplete. Is there a more complete list available for CUPS?
Some examples of printer status state-reasons that are not listed:
cups-waiting-for-job-completed
offline-report
I'm sure there are many more examples but these are the ones I've found and recorded.

Edit: M. Sweet was nice enough to provide this list from IANA: https://www.iana.org/assignments/ipp-registrations/ipp-registrations.xml
The cups source code seems to illustrate quite a few state reasons that don't appear in that RFC. Since the same author -- M. Sweet authors both the RFC as well as maintains the CUPS source code, this may be worth file as a bug report on GitHub to see why the two have diverged.
For example, in 2013, cups-waiting-for-completed was added and about a day later was renamed to cups-waiting-for-job-completed,
which came 4 years before the latest 2017 release of the RFC.
The RFC mentions the following codes in the following order:
none
other
developer-low
door-open
fuser-over-temp
fuser-under-temp
input-tray-missing
interlock-open
interpreter-resource-unavailable
marker-supply-empty
marker-supply-low
marker-waste-almost-full
marker-waste-full
media-empty
media-jam
media-low
media-needed
moving-to-paused
opc-life-over
opc-near-eol
output-area-almost-full
output-area-full
output-tray-missing
paused
shutdown
spool-area-full
stopped-partly
stopping
timed-out
toner-empty
toner-low
However the source code of job.c seems to also mention the following statuses (including the two mention in the question). I think this makes an exhaustive list until more come along.
connecting-to-device
offline-report
cups-insecure-filter-warning
cups-missing-filter-warning
cups-remote-aborted
cups-remote-canceled
cups-remote-completed
cups-remote-pending
cups-remote-pending-held
cups-remote-processing
cups-remote-stopped
cups-waiting-for-job-completed
As to the best way to track the addition of new keywords, M. Sweet may also be able to provide information on where the new state keywords are derived. Here's the commit description of what seems to have prompted the cups-waiting-for-job-completed.
msweet committed on Nov 6, 2013 Dropped "dark wake" support on OS X, which was preventing portables from going to sleep when there was a stuck job. We now use a variation of the CUPS 1.4
sleep support to do a cleaner sleep <rdar://problem/14323704> Aside from removing all of the power assertions, we now track a new "cups-waiting-for-completed" state keyword that tells cupsd it can SIGKILL a backend without side-effects - then if we are just waiting for the job to complete we can go to sleep immediately.

Related

Amending a condition as the stack unwinds in Common Lisp

I'm working on some lisp code that munges a CVS repository in order to get it into shape for a git conversion. As such, when something goes wrong it might not be a bug in my code but might instead be an inaccuracy in the input data which needs fixing.
Deep down in the bowels of my code, I'll have (say) some function that merges two date ranges by taking an intersection. If that intersection turns out to be empty, I'll raise an error. This is all good, but my "merge dates" function is missing lots of the information that the user (me!) needs in order to figure out what went wrong. For example, which CVS master file ("foo,v") was I working on? What branch was I thinking about? Etc. etc.
My partial solution to this problem is to handle and re-raise the error. For example, this sort of code:
(handler-case
(do-something)
(unclear-graft-point (c)
(setf (slot-value c 'master) master)
(setf (slot-value c 'branch) branch)
(error c)))
which sets some extra slots with useful info before re-raising the error.
The report function for the condition then checks whether those slots have been set and, if so, will use them to give a more helpful error message.
Unfortunately, the backtrace that I get stops at the top-level re-raise. That makes sense: it's the code I wrote. But it's not really what I want...
Is there a way in Common Lisp to "annotate" a condition as it hurtles past, without re-raising it and, hence, partially unwinding the stack without reporting that in the back trace?
I gave a reasonable amount of background info about what I'm doing in the hope that, if this isn't possible, someone will say "Ah, what you should do in this situation is...": am I just going about this the wrong way?
Yes, there is a Common Lisp technology applicapble to your case - it is called HANDLER-BIND. You can find a detailed explanation and use cases for it alongside other condition-handling machinery in Peter Seibel's Practical Common Lisp Chapter 19. Conditions and Restarts.

Status of in-place `rfft` and `irfft` in Julia

So I'm doing some hobby-related stuff which involves taking Fourier transforms of large real arrays which barely fit in memory, and was curious to see if there was an in-place version of rfft and irfft that saved RAM, since RAM consumption is important to me. These transforms are possible despite the input-vs-output-type mismatch, and require an extra row of padding.
In Implement in-place rfft! and irfft!, Tim Holy said he was working on an in-place rfft! and irfft! that made use of a buffer-containing RCpair object, but then Steven Johnson said that he was implementing something equivalent using A_mul_B!(y, plan, x), which he elaborated on here.
Things get a little weird from then on. In the documentation for both 0.3.0 and 0.4.0 there is no mention of A_mul_B!, although A_mul_B is listed. But when I try entering them into Julia, I get
A_mul_B!
A_mul_B! (generic function with 28 methods)
A_mul_B
ERROR: A_mul_B not defined
which suggests that the situation is actually the opposite of what the documentation currently describes.
So since A_mul_B! seems to exist, but isn't documented anywhere, I tried to guess how to test it in-place as follows:
A = rand(Float32, 10, 10);
p = plan_rfft(A);
A_mul_B!(A,p,A)
which resulted in
ERROR: `A_mul_B!` has no method matching A_mul_B!(::Array{Float32,2}, ::Function, ::Array{Float32,2})
So...
Are in-place real FFTs still a work in progress? Or am I using A_mul_B! wrong?
Is there a mismatch between the 0.3.0 documentation and 0.3.0's function library?
That pull request from Steven Johnson is listed as open, not merged; that means the work hasn't been finished yet. The one from me is closed, but if you want the code you can grab it by clicking on the commits.
The docs indeed omit mention of A_mul_B!. A_mul_B is equivalent to A*B, and so isn't exported independently now. A_mul_B! would be used like this: instead of C = A*B, you could say A_mul_B!(C, A, B).
Can you please edit the docs to fix these issues? (You can edit files here in your webbrowser.)

Migrating from graphite to graph-explorer

The graphite-webapp does not encourage ad-hoc graphing. Graphiti et al are just fancy UIs that, while improve UI-UX, do not do much regarding the inherent linear metric search that plagues the graphite-webapp. Correct me if wrong here, but the only option I came across that encourages ad-hoc graphing has been Graph-Explorer. Assuming, that Graph-Explorer is the only way ahead.
I have some 1000 distinct metrics currently. Named in the following fashion-
stats.beta.pluto.ip-10-0-1-81.helios.pa.v4.reminder.total
stats.beta.pluto.ip-10-0-1-81.helios.pa.v4.reminder.failed
stats.beta.pluto.ip-10-0-1-81.helios.pa.v4.reminder.delivered
stats.dev.ganglia.ip-10-0-3-40.ink.web.pi.notification.android.total
stats.dev.ganglia.ip-10-0-3-40.ink.web.pi.notification.android.failed
stats.dev.ganglia.ip-10-0-3-40.ink.web.pi.notification.android.delivered
I understand that these will become-
metric=stats.env=dev.role=ganglia.server=ip-10-0-3-40. application=ink.endpoint=web.src=pi.metric=notification.what=total
Where do I insert unit and target_type tags?
Similarly, I have 500 timers.
How do I go about migrating from 'proto1' to 'proto2'?
Also where exactly does Carbon-Tagger come into the stack?
Do I rename my metrics at the source level?
Do I modify the structured_metrics/plugins/statsd.py file as we have fixed hierarchy across our distributed infrastructure?
Anything I am missing?
What will I have to change in my statsd? I quote the carbon-tagger documentation- "aggregators like statsd will need proto2 support."
the structured metrics plugins will set the tags for proto1 ("old style") metrics, see https://github.com/vimeo/graph-explorer/wiki/Structured-Metrics
if you want to stick to proto1 you just have to create a plugin to tag your metrics see https://github.com/vimeo/graph-explorer/wiki/Structured-Metrics#writing-your-own-plugins and existing plugins for examples
you can basically ignore carbon-tagger if you want to stick with proto1, so 3 is not needed, but otherwise yes. the statsd plugin just converts statsd's internal metrics to proto2.

Do you use tense when naming methods of boolean return type?

So, when you are writing a boolean method, do you use tense, like "has" or "was", in your return method naming, or do you solely use "is"?
The following is a Java method I recently wrote, very simply ..
boolean recovered = false;
public boolean wasRecovered()
{
return recovered;
}
In this case, recovered is a state that may or may not have already occurred at this point in the code, so grammatically "was" makes sense. But does it make the same sense in code, where the "is" naming convention is usually standard?
I prefer to use IsFoo(), regardless of tense, simply because it's a well-understood convention that non-native speakers will still generally understand. Non-native speakers of English are a regular consideration in today's global dev't industry.
I use the tense which is appropriate the meaning of the value. To do otherwise essentially creates code which reads one way and behaves another. Lets look at a real world example in the .Net Framework: Thread.IsAlive
This property is presented with the present tense. This has the implication the value refers to the present and makes code like the following read very well
if (thread.IsAlive ) {
// Code that depends on the thread being alive
...
The problem here is that the property does not represent the present state of the object it represents a past state. Once the value is calculated to be true, the thread in question can immediately exit and invalidate the value. Hence the value can only safely be used to identify the past state of the thread and a past tense property is more appropriate. Lets now revisit the sample which reads a bit differently
if ( thread.WasAlive ) {
// Code that depends on the thread being alive
...
They behave the same but one reads very poorly because it in fact represents poor code.
Here's a list of some other offenders
File.Exists
Directory.Exists
DriveInfo.IsReady
WeakReference.IsAlive
The isXxx prefix is a widespread naming convention, so it's generally the best choice.
For order-sensitive operations, wasXxx is appropriate. For example, in JDBC, retrieving the value of a database column might return zero when the field is actually NULL (unset); in this case, a follow-up call to wasNull determines which it is after the actual retrieval was performed.
For retrieving attribute settings, hasXxx may be more appropriate. It's a grammar preference, as in "the object's flag is set" versus "the object has an attribute".
Then there are capability tests canXxx. For example, calling canWrite to see if a file is writable. But names like these can probably be renamed to the isXxx form, such as isWritable.
I tend to, yes. For example in error checking:
$errors = false;
public function hasErrors()
{
return $this->errors;
}
I am not sure that you are thinking about this correctly. The reason one would use the Recovered property is because that is the state the object is in now, not because that was the state the object used to be in. There may have been some process in the past (The Recovery) that has now completed, but the fact that we are accessing this property now means that there is something about that completed process that altered current state, and that current state is important. To me "Recovered" captures the nature of that state. For this example (and most similar situations) I would use IsRecovered to name the predicate that indicates this condition. (This also matches normal English: "This is a recovered document.")
It is extremely rare that I would use anything other than present tense to name a predicate (IsDirty, HasCoupon) or boolean function (IsPrime(x)) in a program.
An exception would be to indicate state that has since been changed that might need to be reinstated (DocumentWindow.WasMaximizedAtLastExit).
I would usually use an infinitive for future tense (ToBeCopied rather than WillBeCopied), since the best laid plans of software are sometimes altered (or cancelled).
It depends on whether or not you care about the past or future state of the property in question.
To try to simplify the semantics, realize that there are a few scenarios that make the IsXXX form debatable and some very common scenarios where the IsXXX form is the only useful one.
Below is the 'truth table' for Thread.IsAlive() based on possible states of the thread over time. Forget about why a thread might flip flop states, we need to focus on the language used.
Scenarios of possible thread states over time:
Past Present Future
===== ======= =======
1. alive alive alive
2. alive alive dead
3. alive dead dead
4. dead dead dead
5. dead dead alive
6. dead alive alive
7. dead alive dead
8. alive dead alive
Note: I talk about the Future state below for consistency. Knowing whether a thread will die is very likely unknowable as a subset of The Halting Problem)
When we interrogate an object by calling a method, there is a common assumption "Is this thread alive, at the time I asked? For these cases, the answer in the "Present" column is all we care about and using the IsXXX form works fine.
Scenarios #1(always alive) and #4(always dead) are the simplest and most common. The answer to IsAlive() will not change between calls. The battle over language that comes up is due to the other 6 cases where the result of calling IsAlive() depends on when it is called.
Scenarios #2(will die) and #3(has died) transitions from alive to dead.
Scenarios #5(will start) and #6(has started) transitions from dead to alive.
For these four (2, 3, 5, 6) the answer to IsAlive() is not constant. The question becomes, do I care about the Present state, IsAlive(), or am I interested in the Past/Future state, WasAlive() and WillBeAlive()? Unless you can predict the future, the WillBeAlive() call becomes meaningless for all but the most specific designs.
When dealing with a thread pool, we might need to restart threads that are in the 'dead' state to service connect requests and it doesn't matter whether they were ever alive, just that they are currently dead. In this case we might actually want to use WasDead(). Of course we should try to guarantee we don't restart a thread that was just restarted but that is a design problem, not a semantic one. Assuming that no one else can restart the thread, it doesn't matter much whether we use IsAlive() == false or WasDead() == true.
Now for the last two scenarios. Scenario #7(was dead, is alive, will be dead) is practically the same as #6. Do you know when in the future it will die? In 10 seconds, 10 minutes, 10 hours? Are you going to wait before deciding what to do. No, you only care about the current (Present) state. We're talking about naming here, not multi-threaded design.
Scenario #8(was alive, is dead, will be alive), is practically the same as #3. If you are reusing threads, then they can cycle through the alive/dead states several times. Worrying about the difference between #3 and #8 goes back to the Halting Problem and so can be disregarded.
IsAlive() should work for all cases. IsAlive() == false works (for #5 and #6) instead of adding WasAlive().
I don't mind wasRecovered that much. Recovery is a past event that may or may not have happened - this tells you whether it did or not. But if you're using it because of some consequence of recovery, I'd prefer isCached, isValid, or some other description of what those consequences actually are. Just because you've recovered something doesn't inherently mean you haven't lost it again since.
Always beware that in English, the use of a past participle as an adjective is ambiguous between transitive and intransitive verbs (and perhaps between active and passive voice). isRecovered might mean that the object has been recovered by something else, or it might mean that the object has recovered. If your object represents a patient at a hospital, does "isRecovered" mean that the patient is fit and well, or that someone has fetched the patient back from the X-ray department? wasRecovered might therefore be better for the latter.
The conceit for method naming is that you are retrieving information about the object in question. For it to be named in the past tense, it would have to be information about a previous state of the object, rather than its current state.
The only reason I could ever think of for using past tense is if I was checking a cached result of something that previously occurred but is no longer the case. For a contrived example, perhaps retriveing the previous value after something like a swap() call. It could be useful in operations that are atomic by design. Not real likely in the wild though.
Since your question is specific to Java, the method name should start with "is" if your class is a JavaBean and the method is an accessor method for a property.
http://download.oracle.com/javase/tutorial/javabeans/properties/properties.html

How can I program a simple chat bot AI?

I want to build a bot that asks someone a few simple questions and branches based on the answer. I realize parsing meaning from the human responses will be challenging, but how do you setup the program to deal with the "state" of the conversation?
It will be a one-to-one conversation between a human and the bot.
You probably want to look into Markov Chains as the basics for the bot AI. I wrote something a long time ago (the code to which I'm not proud of at all, and needs some mods to run on Python > 1.5) that may be a useful starting place for you: http://sourceforge.net/projects/benzo/
EDIT: Here's a minimal example in Python of a Markov Chain that accepts input from stdin and outputs text based on the probabilities of words succeeding one another in the input. It's optimized for IRC-style chat logs, but running any decent-sized text through it should demonstrate the concepts:
import random, sys
NONWORD = "\n"
STARTKEY = NONWORD, NONWORD
MAXGEN=1000
class MarkovChainer(object):
def __init__(self):
self.state = dict()
def input(self, input):
word1, word2 = STARTKEY
for word3 in input.split():
self.state.setdefault((word1, word2), list()).append(word3)
word1, word2 = word2, word3
self.state.setdefault((word1, word2), list()).append(NONWORD)
def output(self):
output = list()
word1, word2 = STARTKEY
for i in range(MAXGEN):
word3 = random.choice(self.state[(word1,word2)])
if word3 == NONWORD: break
output.append(word3)
word1, word2 = word2, word3
return " ".join(output)
if __name__ == "__main__":
c = MarkovChainer()
c.input(sys.stdin.read())
print c.output()
It's pretty easy from here to plug in persistence and an IRC library and have the basis of the type of bot you're talking about.
Folks have mentioned already that statefulness isn't a big component of typical chatbots:
a pure Markov implementations may express a very loose sort of state if it is growing its lexicon and table in real time—earlier utterances by the human interlocutor may get regurgitated by chance later in the conversation—but the Markov model doesn't have any inherent mechanism for selecting or producing such responses.
a parsing-based bot (e.g. ELIZA) generally attempts to respond to (some of the) semantic content of the most recent input from the user without significant regard for prior exchanges.
That said, you certainly can add some amount of state to a chatbot, regardless of the input-parsing and statement-synthesis model you're using. How to do that depends a lot on what you want to accomplish with your statefulness, and that's not really clear from your question. A couple general ideas, however:
Create a keyword stack. As your human offers input, parse out keywords from their statements/questions and throw those keywords onto a stack of some sort. When your chatbot fails to come up with something compelling to respond to in the most recent input—or, perhaps, just at random, to mix things up—go back to your stack, grab a previous keyword, and use that to seed your next synthesis. For bonus points, have the bot explicitly acknowledge that it's going back to a previous subject, e.g. "Wait, HUMAN, earlier you mentioned foo. [Sentence seeded by foo]".
Build RPG-like dialogue logic into the bot. As your parsing human input, toggle flags for specific conversational prompts or content from the user and conditionally alter what the chatbot can talk about, or how it communicates. For example, a chatbot bristling (or scolding, or laughing) at foul language is fairly common; a chatbot that will get het up, and conditionally remain so until apologized to, would be an interesting stateful variation on this. Switch output to ALL CAPS, throw in confrontational rhetoric or demands or sobbing, etc.
Can you clarify a little what you want the state to help you accomplish?
Imagine a neural network with parsing capabilities in each node or neuron. Depending on rules and parsing results, neurons fire. If certain neurons fire, you get a good idea about topic and semantic of the question and therefore can give a good answer.
Memory is done by keeping topics talked about in a session, adding to the firing for the next question, and therefore guiding the selection process of possible answers at the end.
Keep your rules and patterns in a knowledge base, but compile them into memory at start time, with a neuron per rule. You can engineer synapses using something like listeners or event functions.
I think you can look at the code for Kooky, and IIRC it also uses Markov Chains.
Also check out the kooky quotes, they were featured on Coding Horror not long ago and some are hilarious.
I think to start this project, it would be good to have a database with questions (organized as a tree. In every node one or more questions).
These questions sould be answered with "yes " or "no".
If the bot starts to question, it can start with any question from yuor database of questions marked as a start-question. The answer is the way to the next node in the tree.
Edit: Here is a somple one written in ruby you can start with: rubyBOT
naive chatbot program. No parsing, no cleverness, just a training file and output.
It first trains itself on a text and then later uses the data from that training to generate responses to the interlocutor’s input. The training process creates a dictionary where each key is a word and the value is a list of all the words that follow that word sequentially anywhere in the training text. If a word features more than once in this list then that reflects and it is more likely to be chosen by the bot, no need for probabilistic stuff just do it with a list.
The bot chooses a random word from your input and generates a response by choosing another random word that has been seen to be a successor to its held word. It then repeats the process by finding a successor to that word in turn and carrying on iteratively until it thinks it’s said enough. It reaches that conclusion by stopping at a word that was prior to a punctuation mark in the training text. It then returns to input mode again to let you respond, and so on.
It isn’t very realistic but I hereby challenge anyone to do better in 71 lines of code !! This is a great challenge for any budding Pythonists, and I just wish I could open the challenge to a wider audience than the small number of visitors I get to this blog. To code a bot that is always guaranteed to be grammatical must surely be closer to several hundred lines, I simplified hugely by just trying to think of the simplest rule to give the computer a mere stab at having something to say.
Its responses are rather impressionistic to say the least ! Also you have to put what you say in single quotes.
I used War and Peace for my “corpus” which took a couple of hours for the training run, use a shorter file if you are impatient…
here is the trainer
#lukebot-trainer.py
import pickle
b=open('war&peace.txt')
text=[]
for line in b:
for word in line.split():
text.append (word)
b.close()
textset=list(set(text))
follow={}
for l in range(len(textset)):
working=[]
check=textset[l]
for w in range(len(text)-1):
if check==text[w] and text[w][-1] not in '(),.?!':
working.append(str(text[w+1]))
follow[check]=working
a=open('lexicon-luke','wb')
pickle.dump(follow,a,2)
a.close()
here is the bot
#lukebot.py
import pickle,random
a=open('lexicon-luke','rb')
successorlist=pickle.load(a)
a.close()
def nextword(a):
if a in successorlist:
return random.choice(successorlist[a])
else:
return 'the'
speech=''
while speech!='quit':
speech=raw_input('>')
s=random.choice(speech.split())
response=''
while True:
neword=nextword(s)
response+=' '+neword
s=neword
if neword[-1] in ',?!.':
break
print response
You tend to get an uncanny feeling when it says something that seems partially to make sense.
I would suggest looking at Bayesian probabilities. Then just monitor the chat room for a period of time to create your probability tree.
I'm not sure this is what you're looking for, but there's an old program called ELIZA which could hold a conversation by taking what you said and spitting it back at you after performing some simple textual transformations.
If I remember correctly, many people were convinced that they were "talking" to a real person and had long elaborate conversations with it.
If you're just dabbling, I believe Pidgin allows you to script chat style behavior. Part of the framework probably tacks the state of who sent the message when, and you'd want to keep a log of your bot's internal state for each of the last N messages. Future state decisions could be hardcoded based on inspection of previous states and the content of the most recent few messages. Or you could do something like the Markov chains discussed and use it both for parsing and generating.
If you do not require a learning bot, using AIML (http://www.aiml.net/) will most likely produce the result you want, at least with respect to the bot parsing input and answering based on it.
You would reuse or create "brains" made of XML (in the AIML-format) and parse/run them in a program (parser). There are parsers made in several different languages to choose from, and as far as I can tell the code seems to be open source in most cases.
You can use "ChatterBot", and host it locally using - 'flask-chatterbot-master"
Links:
[ChatterBot Installation]
https://chatterbot.readthedocs.io/en/stable/setup.html
[Host Locally using - flask-chatterbot-master]: https://github.com/chamkank/flask-chatterbot
Cheers,
Ratnakar