Gremlin GroovyTranslator generates wrong result and fails at remote server - gremlin

I am using Gremlin java and I found GroovyTranslator adds additional \ before $ sign,
and this causes query failing to execute on remote server.
GraphTraversal traversal = graph.addV().property("amount", "$1");
System.out.println(GroovyTranslator.of("g").translate(traversal.asAdmin().getBytecode()));
Translated result:
g.addV().property("amount","\$1")
If this is issue with GroovyTranslator, i can replace \$ with $, but I am not sure if more special characters will have this issue.
This fails because of backslash, but what if some property value want to use backslash?
From what I see, use backslash will always fail.
I suppose following should work but it doesn't:
curl -X POST -d '{"gremlin":"g.V().has(\"key\",\"\\$\")"}' ...

In Groovy the dollar sign has special meaning if you are using Groovy Strings (GStrings). It is used to indicate interpolation should occur as in :
gremlin> a=3
==>3
gremlin> "The number is $a"
==>The number is 3
If the server you are connecting to uses Groovy as-is to parse the query then the backslash is needed. If the server does not use Groovy as-is then you will need to remove the backslash.
There are a few other things to be aware of with GroovyTranslator. When it generates literal numbers it puts a cast such as (int) 3 into the query. You may need to also remove these depending on the back end graph database you are connecting to.

Related

How to parse #{TEST TAGS} into only the Tags, eliminating current formatting?

Situation.. I have two tags defined, then I try to output them to the console. What comes out seems to be similar to an array, but I'd like to remove the formatting and just have the actual words outputted.
Here's what I currently have:
[Tags] ready ver10
Log To Console \n#{TEST TAGS}
And the result is
['ready', 'ver10']
So, how would I chuck the [', the ', ' and the '], thus only retaining the words ready and ver10?
Note: I was getting [u'ready', u'ver10'] - but once I got some advice to make sure I was running Python3 RobotFramework - after uninstalling robotframework via pip, and now only having robotframework installed via pip3, the u has vanished. That's great!
There are several ways to do it. For example, you could use a loop, or you could convert the list to a string before calling log to console
Using a loop.
Since the data is a list, it's easy to iterate over the list:
FOR ${tag} IN #{Test Tags}
log to console ${tag}
END
Converting to a string
You can use the evaluate keyword to convert the list to a string of values separated by a newline. Note: you have to use two backslashes in the call to evaluate since both robot and python use the backslash as an escape character. So, the first backslash escapes the second so that python will see \n and convert it to a newline.
${tags}= evaluate "\\n".join($test_tags)
log to console \n${tags}

How to process latex commands in R?

I work with knitr() and I wish to transform inline Latex commands like "\label" and "\ref", depending on the output target (Latex or HTML).
In order to do that, I need to (programmatically) generate valid R strings that correctly represent the backslash: for example "\label" should become "\\label". The goal would be to replace all backslashes in a text fragment with double-backslashes.
but it seems that I cannot even read these strings, let alone process them: if I define:
okstr <- function(str) "do something"
then when I call
okstr("\label")
I directly get an error "unrecognized escape sequence"
(of course, as \l is faultly)
So my question is : does anybody know a way to read strings (in R), without using the escaping mechanism ?
Yes, I know I could do it manually, but that's the point: I need to do it programmatically.
There are many questions that are close to this one, and I have spent some time browsing, but I have found none that yields a workable solution for this.
Best regards.
Inside R code, you need to adhere to R’s syntactic conventions. And since \ in strings is used as an escape character, it needs to form a valid escape sequence (and \l isn’t a valid escape sequence in R).
There is simply no way around this.
But if you are reading the string from elsewhere, e.g. using readLines, scan or any of the other file reading functions, you are already getting the correct string, and no handling is necessary.
Alternatively, if you absolutely want to write LaTeX-like commands in literal strings inside R, just use a different character for \; for instance, +. Just make sure that your function correctly handles it everywhere, and that you keep a way of getting a literal + back. Here’s a suggestion:
okstr("+label{1 ++ 2}")
The implementation of okstr then needs to replace single + by \, and double ++ by + (making the above result in \label{1 + 2}). But consider in which order this needs to happen, and how you’d like to treat more complex cases; for instance, what should the following yield: okstr("1 +++label")?

ZSH prompt substitution issues

I've searched through several answers here and through Google, but I'm still not sure what's going wrong with my prompt.
According to the documentation I've read, this should work
setopt prompt_subst
autoload -U colors && colors
PROMPT="%{[00m[38;5;245m%}test %D%{[00m%}"
My prompt is the following, however:
[00m[38;5;245mtest 15-07-01[00m
Note that the date expansion actually worked, so prompt substitution is working. The ZSH man pages for prompt expansion states that %{...%} should be treated as a raw escape code, but that doesn't seem to be happening. Passing that string to print -P also results in the output above. I've found example prompts on the Internet for ZSH that also seem to indicate that the above syntax should work. See this for one example - the $FG and $FX arrays are populated with escape codes and are defined here. I've tried this example directly by merging both the files above, adding setopt prompt_subst to the beginning just to make sure it's set, then sourcing it and the prompt is a mess of escape codes.
The following works
setopt prompt_subst
autoload -U colors && colors
PROMPT=$'%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}'
I get the expected result of test 15-07-01 in the proper color.
I've tested this on ZSH 5.0.5 in OSX Yosimite, 5.0.7 from MacPorts, and 4.3.17 on Debian, with the same results. I know I have provided a valid solution to my own problem here with the working example, but I'm wondering why the first syntax isn't working as it seems it should.
I think this all has to do with the timeless and perennial problem of escaping. It's worth reminding ourselves what escaping means, briefly: an escape character is an indicator to the computer that what follows should not be output literally.
So there are 2 escaping issues with:
PROMPT="%{[00m[38;5;245m%}test %D%{[00m%}"
Firstly, the colour escape sequences (eg; [00m) should all start with the control character like so \e[00m. You may have also seen it written as ^[00m and \003[00m. What I suspect has happened is one of the variations has suffered the common fate of being inadvertently escaped by either the copy/paste of the author or the website's framework stack, whether that be somewhere in a database, HTTP rendering or JS parsing. The control character (ie, ^, \e or \003), as you probably know, does not have a literal representation, say if you press it on the keyboard. That's why a web stack might decide to not display anything if it sees it in a string. So let's correct that now:
PROMPT="%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}"
This actually nicely segues into the next escaping issue. Somewhat comically \e[ is actually a representation of ESC, it is therefore in itself an escape sequence marker that, yes, is in turn escaped by \. It's a riff on the old \\\\\\\\\\ sort of joke. Now, significantly, we must be clear on the difference between the escape expressions for the terminal and the string substitutions of the prompt, in pseudo code:
PROMPT="%{terminal colour stuff%}test %D%{terminal colour stuff%}"
Now what I suspect is happening, though I can't find any documentation to prove it, is that once ZSH has done its substitutions, or indeed during the substitution process, all literal characters, regardless of escape significations, are promoted to real characters¹. To yet further the farce, this promotion is likely done by escaping all the escape characters. For example if you actually want to print '\e' on the command line, you have to do echo "\\\e". So to overcome this issue, we just need to make sure the 'terminal colour stuff' escape sequences get evaluated before being assigned to PROMPT and that can be done simply with the $'' pattern, like so:
PROMPT=$'%{\e[00m\e[38;5;245m%}test %D%{\e[00m%}'
Note that $'' is of the same ilk as $() and ${}, except that its only function is to interpret escape sequences.
[1] My suspicion for this is based on the fact that you can actually do something like the following:
PROMPT='$(date)'
where $(date) serves the same purpose as %D, by printing a live version of the date for every new prompt output to the screen. What this specific examples serves to demonstrate is that the PROMPT variable should really be thought of as storage for a mini script, not a string (though admittedly there is overlap between the 2 concepts and thus stems confusion). Therefore, as a script, the string is first evaluated and then printed. I haven't looked at ZSH's prompt rendering code, but I assume such evaluation would benefit from native use of escape sequences. For example what if you wanted to pass an escape sequence as an argument to a command (a command that gets run for every prompt render) in the prompt? For example the following is functionally identical to the prompt discussed above:
PROMPT='%{$(print "\e[00m\e[38;5;245m")%}test $(date)%{$(print "\e[00m")%}'
The escape sequences are stored literally and only interpreted at the moment of each prompt rendering.

Is it possible to disable Command Substitution in Bash?

Is it possible to disable Command Substitution in Bash?
I want to pass a string containing several backticks characters as command-line argument to a program, without trailing backslashs or quoting the string.
Thank you.
I assume there is a misconception which grounds your question. Quoting is most likely the solution to your situation. But maybe you haven't found the right way of quoting yet or similar.
If your dangerous string shall be verbatim (without quoting or escaping) in the source code, you can put it in a separate file and read it from there:
dangerous_string=$(cat dangerous_string_file.txt)
If it shall be passed without interpretation to a command, use the double quotes to prevent interpretation:
my_command "$dangerous_string"
If you have to pass it to a command which needs to receive a quoted version of your string because it is known to carelessly pass the string without using sth like the double quotes to prevent interpretation, you can always use printf to get a quoted version:
quoted_dangerous_string=$(printf "%q" "$dangerous_string")
careless_command "$quoted_dangerous_string"
If all these options do not help in your situation, please explain in more detail where your problem lies.

Autosys Job depends regular expression

I am using the Jobdepends command to get a list of jobs stating with tax_check_d_%
I need files like tax_check_d_job
but it returns
tax_check_djob
tax_check_d_job
tax_check_djob_job
how can i select only tax_check_d_job?
When used in a job filter, the _ (underscore) character is a wildcard that matches exactly one character. This explains why you are seeing the unwanted results coming back -tax_check_d_job_% is essentially the same as tax_check_d_job%.
Unfortunately I don't think there's a way around this - according to the Autosys 4.0 reference guide, the SQL ESCAPE option is not supported for wildcards.
I would suggest adding one more character onto your search criteria to filter out the unwanted results, running the command multiple times if necessary. E.g. run it with tax_check_d_job_a%, tax_check_d_job_b%, ... as necessary.
You could also use some custom code to strip out the results you don't want to see. Depending on your needs, this could be a simple as
job_depends -d -J tax_check_d_job_% | grep "tax_check_d_job_.*"

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