i am trying to parse the below log
2015-07-07T17:51:30.091+0530,857,SelectAppointment,Non HTTP response code: java.net.URISyntaxException,FALSE,8917,20,20,0,1,1,byuiepsperflg01
Now I am unable to parse Non HTTP response code: java.net.URISyntaxException in one field. Please help be build the pattern
This is the pattern I'm using
%{TIMESTAMP_ISO8601:log_timestamp}\,%{INT:elapsed}\,%{WORD:label}\,%{INT:responsecode}\,%{WORD:responsemessage}\,%{WORD:success}\,%{SPACE:faliusemessage}\,%{INT:bytes}\,%{INT:grpThreads}\,%{INT:allThreads}\,%{INT:Latency}\,%{INT:SampleCount}\,%{INT:ErrorCount}\,%{WORD:Hostname}
If you paste your input and pattern into the grok debugger, it says "Compile ERROR". It might be an SO problem, but you had some weird characters in your pattern ("<200c><200b>").
The trick to building custom patterns is to start at the left side and pull one piece off at a time. With that, you would notice that this partial pattern works:
%{TIMESTAMP_ISO8601:log_timestamp},%{INT:elapsed},%{WORD:label}
but this one returns "No Matches":
%{TIMESTAMP_ISO8601:log_timestamp},%{INT:elapsed},%{WORD:label},%{INT:responsecode}
because you don't have an integer in that position.
Continue adding fields one at a time until everything you want is matched.
Note that you don't have to escape the commas.
Related
I need to get the pieces of text out of text)). Very simple example actually, but gives me quite some pain.
Here is the sample text, it is an email template:
{!Account.Name}
Hi hi there {!Account.Id + 'cool'}.
Very interesting stuff - {!Contact.Description}
Now we get {!Contact.Description + Contact.Email__c}
So I need all the occurances of text like Account.Name, but only those which are within opening "{!" and closing "}" tags.
What is the simplest/starting approach to do it? Note that in case of the last line, I need to get the two occurances, Contact.Description and Contact.Email__c.
Thanks a lot for any help!
I would just do a plain text search for {...} blocks and parse their content with a simple expression parser. Don't try to come up with a parser that gets all the text and must be prepared to deal with any rubbish that can come in outside of the blocks (which could ultimatively lead to security problems).
i am facing an issue in parsing the below pattern
the log file will have log importance in the form of == or <= or >= or << or >>
I am trying the below custom pattern. Some of the log msgs may not have this pattern, so I am using *
(?(=<>)*)
But the log mesages are not parsing and give 'grokparsefailure'
kindly check and suggest if the above pattern is wrong.. Thanks much
below pattern is working fine.
(?[=<>]*)
the one which I used earlier and was erroring is
(?(=<>)*)
One thing to note, there is a better way to handle the "some do, some don't" aspect of your log-data.
(?<Importance>(=<>)*)
That will match more than you want. To get the sense of 'sometimes':
((?<Importance>(=<>)*)|^)
This says, match these three characters and define the field Importance, or leave the field unset.
Second, you're matching specifically two characters, in combinations:
((?<Importance>(<|>|=){2})|^)
This should match two instances of any of the trio of characters you're looking for.
I'm new to ANTL4 and I can't seem to figure out how to get lexer actions to perform properly.
I have a code snippet that looks for input text:
SIZE10 : [a-zA-Z]* {getText().length() <= 10}?
I would expect that it does not match any combinations of letters that are over 10 letters long, however what this does is treat a 10+ letter string as two different tokens, instead of just nullifying the whole set of 10+ letters. How can I get this action to nullify the whole set of letters?
In addition, where can I go to see all the different token functions I can use (other than getText())? The documentation about lexer actions is really poor. In general, I'm having a hard time figuring out what resources can give me a definitive list of everything in the language. Even an entry point into the source code for me to read would be good at this point. The documentation is too general/basic for me.
EDIT: I've figured out how to send a RuntimeException, but I don't know where to get the elements needed for a proper RecognitionException.
The predicate in a rule directs the parsing process in a way that allows to match only partial input (like in your case) or essentially switch off a part of the grammar depending on certain conditions. In your case the SIZE10 rule is matched until the predicate returns false. Everything up to this event is then returned as a match for SIZE10. After that lexing continues at the point it ended for the previous token and if that is again a letter it will again match SIZE10 as long as the predicate says it is correct. That's a bit different than what you would expect (e.g. using the predicate as an all or nothing switch).
However, if you instead want to match the full set of letters first and then check if the length is <= 10 you can do this in a listener. You can hook into the exitSIZE10() event and reject the match by throwing a recognition exception.
For the usable functions in your actions see the API documentation for ANTLR. For instance here is the one for Token which shows you other possibilities beside getText(). In your action, consider the context you have. In a lexer rule you deal with a Token, hence getText() etc. work on the token. In a parser rule you have a ParserContext instead, which also has a getText() function but that works differently (collecting all child contexts text into a comma separated list).
I am new to Antlr4 and have been wracking my brain for some days now about a behaviour that I simply don't understand. I have the following combined grammar and expect it to fail and report an error, but it doesn't:
grammar MWE;
parse: cell EOF;
cell: WORD;
WORD: ('a'..'z')+;
If I feed it the input
a4
I expect it to not be able to parse it, because I want it to match the whole input string and not just a part of it, as signified by the EOF. But instead it reports no error (I listen for errors with a errorlistener implementing the IAntlrErrorListener interface) and gives me the following parse tree:
(parse (cell a) <EOF>)
Why is this?
The error recovery mechanism when input is reached which no lexer rule matches is to drop a character and continue with the next one. In your case, the lexer is dropping the 4 character, so your parser is seeing the equivalent of this input:
a
The solution is to instruct the lexer to create a token for the dropped character rather than ignore it, and pass that token on to the parser where an error will be reported. In the grammar, this rule takes the following form and is always added as the last rule in the grammar. If you have multiple lexer modes, a rule with this form should appear as the last rule in the default mode as well as the last rule in each extra mode.
ErrChar
: .
;
I'm getting a garbled JSON string from a HTTP request, so I'm looking for a temp solution to select the JSON string only.
The request.params() returns this:
[{"insured_initials":"Tt","insured_surname":"Test"}=, _=1329793147757,
callback=jQuery1707229194729661704_1329793018352
I would like everything from the start of the '{' to the end of the '}'.
I found lots of examples of doing similar things with other languages, but the purpose of this is not to only solve the problem, but also to learn Scala. Will someone please show me how to select that {....} part?
Regexps should do the trick:
"\\{.*\\}".r.findFirstIn("your json string here")
As Jens said, a regular expression usually suffices for this. However, the syntax is a bit different:
"""\{.*\}""".r
creates an object of scala.util.matching.Regex, which provides the typical query methods you may want to do on a regular expression.
In your case, you are simply interested in the first occurrence in a sequence, which is done via findFirstIn:
scala> """\{.*\}""".r.findFirstIn("""[{"insured_initials":"Tt","insured_surname":"Test"}=, _=1329793147757,callback=jQuery1707229194729661704_1329793018352""")
res1: Option[String] = Some({"insured_initials":"Tt","insured_surname":"Test"})
Note that it returns on Option type, which you can easily use in a match to find out if the regexp was found successfully or not.
Edit: A final point to watch out for is that the regular expressions normally do not match over linebreaks, so if your JSON is not fully contained in the first line, you may want to think about eliminating the linebreaks first.