I have a couple scenarios where a series of arbitrary string values have a specific priority sequence. For example:
forgo > log > assert
exception > failure > error > warning > alert
And, I need to evaluate an arbitrary number of scenarios that resolve to one of those values and maintain a running status. So, using the simpler example, if every evaluation is assert then the final running status would be assert. But if a single evaluation is log and the rest are assert, the the final running status is log. And a single forgo means the final status is forgo, no matter what the mix of individual status results was. I want to provide a human readable running status and individual status, do the math to determine what the new running index is, then return the human readable status.
So, I have this, and it works.
$statusIndex = #('assert', 'log', 'forgo')
$runningStatus = 'forgo'
$individualStatus = 'log'
$runningStatusIndex = $statusIndex.indexof($runningStatus)
$individualStatusIndex = $statusIndex.indexof($individualStatus)
if ($individualStatusIndex -gt $runningStatusIndex) {
$runningStatusIndex = $individualStatusIndex
}
$runningStatus = $statusIndex[$runningStatusIndex]
But, this feels like something that happens often enough that there may be a more "native" way to do it. Some built in PowerShell functionality that handles the same thing more elegantly and in less code.
Is my intuition correct, and there is a native way? Or, perhaps a more elegant approach than what I have here?
Put your terms in an array, in precedence order:
$statusIndex = #('forgo', 'log', 'assert')
Aggregate all your status values and remove any duplicates:
$statusValues = 'assert', 'assert', 'log', 'assert'
$statusValueSet = $statusValues |Sort -Unique
Now use the .Where() extension method to select only the first matching term from the precedence list:
$overallStatus = $statusIndex.Where({$_ -in $statusValueSet}, 'First')
Value of $overallStatus should now be 'log' as expected.
3-4 lines of code instead of 9-10 :)
Related
I am newbie to drools. Need understanding how to cascade filtered data from one condition to next one as shown below.
rule "rulename"
when
$var1 : MainObj(filter1)
$var2 : SubObj() from $var1.getSubObj // need all SubObj without any filter here for then clause.
$var3 : SubObj(conditions) from $var2 // Need a subset of SubObj for another then clause
then
$var2.doSomething()
$var3.doVar3Stuff()
end
How can I achieve that?
Continuation of my original post..
i have below rule computing statistics of a rule execution as below.
rule "myrule"
when
$a:wrapper(isActive("ruleName") && dataTypeCode.equals("typeCodeinDB"))
$total : Number() from accumulate($entity: MyObj(ObjAttribute=='testValue') from $a.getMyObj() , count( $entity ))
$filter: MyObj(ObjAttribute=="testValue" && ObjAttribute2.equals("ValidValue")) from $a.getMyObj()
then
$filter.addToResults($filter.getRuleConstituents(),1,drools.getRule().getName(),null); // Add data for insertion in DB at later stage
$filter.addPayloadExecution($a.dataTypeCode(),$a.getMyObj().toString(),$a.getMyObj().size()); //Total Count of MyObj
$filter.addRuleExecutions(drools.getRule().getName(), $total); // anotehr slice of data
end
Here.. i am computing two stats.. Total count of MYObj(), apply some filter for data validation and compute count of valid list ($filter is valid data)
When I run that code I am getting error as below
Exception executing consequence for rule "MyRule" in moneta.rules: [Error: $filter.addRuleExecutions(drools.getRule().getName(), $total): null]
[Near : {... $filter.addToResults($filter.get ....}]
^
[Line: 1, Column: 1]
Need advice on resolving this.
I can't tell if you're trying to change the data in one rule and make it visible in another, or if you're trying to do a single complex condition in a single rule. So I'll outline how both work.
Complex conditions
The pseudo-code in your rule indicates that you have a main object with a filter and a collection of sub-objects. You need to get a list of all sub-objects without a filter, and also to get a list of sub-objects that meet some sort of condition.
To collect these sublists, we have two available operations: accumulate and collect. Since you didn't give a real example, just some psuedo-code, I can't say for sure which is the correct one for you to use. The example I present below uses collect because it is appropriate for this use case. For more information about these operations, refer to the Drools documentation. I've linked to the section on operators; scroll down to see the details for collect and accumulate.
So imagine I have an app that is modeling a school, and my KindergartenClass object has a List of Student objects. In this case, KindergartenClass is the main object, and Student is the sub-object. My Students have names, ages, and an Allergies object that indicates food allergies. Students without Allergies have no allergy object. This is going to be the filter for the example rule -- finding the students without allergies.
The rule would then look like:
rule "EXAMPLE"
when
KindergartenClass( $students: students ) // $var1
// Find all students with no allergies, $var2
$var2: List() from collect( Student( allergies == null ) from $students )
// Find all students who are older than 5, $var3
$var3: List() from collect( Student( age > 5 ) from $students )
then
...
end
Obviously your right-hand-side would have to be adjusted because 'List' has no doSomething() and doVar3Stuff() methods. But without an actual example rule for what you're attempting I can't be more specific here.
You could get the individual students from the lists like this:
$studentWithoutAllergies: Student() from $var2
$studentOlderThan5: Student() from $var3
... but then your then-clause would trigger once for every single $studentWithoutAllergies and $studentOlderThan5. Most people don't want a cartesian product all elements in two lists and then having their consequences firing for each of those products.
Of course, you also talk about "cascading", though it's rather unclear what you mean. If you mean that you want $var3 to be a subset of what you found in $var2, then it's as simple as changing the from clause. So in the example I've been working with, if you actually want all students older than 5 who have no allergies, you can simply change the when clause to be:
// Find all students with no allergies, $var2
$var2: List() from collect( Student( allergies == null ) from $students )
// Find the subset of the non-allergy students who are older than 5, $var3
$var3: List() from collect( Student( age > 5 ) from $var2 )
Changing the data that triggers the rule
There are two keywords available for changing the data available to the left hand side (when clause): update and insert. Which one you use depends on what you're trying to do, and come with very different considerations in terms of performance.
When you ask Drools to fire a set of rules, it first goes through all of the rules and determines if the rule fires, given the data you've inputted. Basically it just goes through, in order, all of the when clauses and decides if the rule is activated or not. Then, once it has the sub-set of rules, in order, it goes through, one by one, executing the right hand side.
If you call update in your right hand side (then clause), then this process repeats: all rules are evaluated again, from the top, including the rule you just fired. If you call insert in your then clause, then the new data is put into working memory, and Drools re-evaluates all of the remaining rules in its execution list. (So, for example, if Drools had decided that rules A, B, C, and D met their when criteria, and B inserts a new fact into working memory, then C and D would be re-evaluated to make sure that they were still valid.)
This is how you'd use them:
rule "Example rule with Update"
when
$input: MyAwesomeInputObject(someValue == 0)
then
$input.setSomeValue(99);
$input.doSomeStuff();
update($input);
end
rule "Example rule with Insert"
when
Person(name == "Bob")
not( Age() )
then
Age age = new Age(18);
insert(age); // there is now an Age object in working memory
end
I'm not 100% familiar with your use case, but I'm going to assume you want to fire all of the filtering rules a second time after your initial rule fires, with the updated data. So I'd do something like this:
rule "rulename"
when
$var1 : MainObj(filter1)
$var2 : SubObj() from $var1.getSubObj // need all SubObj without any filter here for then clause.
$var3 : SubObj(conditions) from $var2 // Need a subset of SubObj for another then clause
then
$var2.doSomething();
$var3.doVar3Stuff();
update($var1); // update the var1 in working memory
end
I have no idea what your when clause is trying to do, since it doesn't appear to match the comments and the syntax is completely wonky. So only the right hand side (then clause) has been adjusted. I have added update($var1) so it will refire the rules with the new instance of $var1 that should have your changes in it.
Of course, once you start re-firing all rules, you run the risk of having rules loop. If this does happen, you will see spikes of CPU and apparent thread deadlocks (this is useful to alert on.) Note that there is a no-loop property, but it won't help when you're calling update.
Using Kapacitor 1.3 and I am trying to use the following where node to keep measurements with an empty tag. Nothing is passing through and I get the same result with ==''.
| where(lambda: 'process-cpu__process-name' =~ /^$/)
I can workaround this issue using a default value for missing tags and filter on this default tag, in the following node but I am wondering if there is a better way structure the initial where statement and avoid an extra node.
| default()
.tag('process-cpu__process-name','system')
| where(lambda: \"process-cpu__process-name\" == 'system' )
Sure it doesn't pass, 'cause this
'process-cpu__process-name'
is a string literal it TICKScript, not a reference to a field, which is
"process-cpu__process-name"
You obviously got the condition always false in this case.
Quite common mistake though, especially for someone with previous experience with the languages that tolerates both single & double quote for mere string. :-)
Also, there's a function in TICKScript lambda called strLength(), find the doc here, please.
Ok, I've been stuggling with this one for a while, and have spent a lot of time trying different things to do something that I have done very easily using PHP.
I am trying to iterate over a list while keeping track of a variable locally, while spitting out HTML attempting to populate a table.
Attempt #1:
#{
var curDate : Date = null
for(ind <- indicators){
if(curDate == null || !curDate.equals(ind.getFirstFound())){
curDate = ind.getFirstFound()
<tr><th colspan='5' class='day'>#(ind.getFirstFound())</th></tr>
<tr><th>Document ID</th><th>Value</th><th>Owner</th><th>Document Title / Comment</th></tr>
}
}
}
I attempt too user a scala block statement to allow me to keep curDate as a variable within the created scope. This block correctly maintains curDate state, but does not allow me to output anything to the DOM. I did not actually expect this to compile, due to my unescaped, randomly thrown in HTML, but it does. this loop simply places nothing on the DOM, although the decision structure is correctly executed on the server.
I tried escaping using #Html('...'), but that produced compile errors.
Attempt #2:
A lot of google searches led me to the "for comprehension":
#for(ind <- indicators; curDate = ind.getFirstFound()){
#if(curDate == null || !curDate.equals(ind.getFirstFound())){
#(curDate = ind.getFirstFound())
}
<tr><th colspan='5' class='day'>#(ind.getFirstFound())</th></tr>
<tr><th>Document ID</th><th>Value</th><th>Owner</th><th>Document Title / Comment</th></tr>
}
Without the if statement in this block, this is the closest I got to doing what I actually wanted, but apparently I am not allowed to reassign a non-reference type, which is why I was hoping attempt #1's reference declaration of curDate : Date = null would work. This attempt gets me the HTML on the page (again, if i remove the nested if statement) but doesn't get me the
My question is, how do i implement this intention? I am very painfully aware of my lack of Scala knowledge, which is being exacerbated by Play templating syntax. I am not sure what to do.
Thanks in advance!
Play's template language is very geared towards functional programming. It might be possible to achieve what you want to achieve using mutable state, but you'll probably be best going with the flow, and using a functional solution.
If you want to maintain state between iterations of a loop in functional programming, that can be done by doing a fold - you start with some state, and on each iteration, you get the previous state and the next element, and you then return the new state based on those two things.
So, looking at your first solution, it looks like what you're trying to do is only print an element out if it's date is different from the previous one, is that correct? Another way of putting this is you want to filter out all the elements that have a date that's the same date as the previous one. Expressing that in terms of a fold, we're going to fold the elements into a sequence (our initial state), and if the last element of the folded sequence has a different date to the current one, we add it, otherwise we ignore it.
Our fold looks like this:
indicators.foldLeft(Vector.empty[Indicator]) { (collected, next) =>
if (collected.lastOption.forall(_.getFirstFound != next.getFirstFound)) {
collected :+ next
} else {
collected
}
}
Just to explain the above, we're folding into a Vector because Vector has constant time append and last, List has n time. The forall will return true if there is no last element in collected, otherwise if there is, it will return true if the passed in lambda evaluates to true. And in Scala, == invokes .equals (after doing a null check), so you don't need to use .equals in Scala.
So, putting this in a template:
#for(ind <- indicators.foldLeft(Vector.empty[Indicator]) { (collected, next) =>
if (collected.lastOption.forall(_.getFirstFound != next.getFirstFound)) {
collected :+ next
} else {
collected
}
}){
...
}
I have an index that looks like this:
index user_core
{
source = user_core_0
path = ...
charset-type = utf-8
min_infix_length = 3
enable_star = 1
}
We escape and wrap all of our searches in asterisks. Every so often, we'll come across a
very strange case in which something such as the following happens:
Search: mocuddles
Results: All users with nicknames containing "yellowstone".
This behavior seems unpredictable, but will happen every time on terms it does effect.
I've been told that there's no real way to debug Sphinx indexes. Is this true? Is there
any sort of "explain query" functionality?
I've confirmed at this point that these are instances of CRC32 hash collisions. Bummer.
What is the easiest way to get all top level entry values from a notes view? I have found the property "TopLevelEntryCount" returning the number of alle categories, but I want the values, too.
To iterate the view entries and column values need too much time.
Set ecl = view.Allentries
Set ve = ecl.Getfirstentry()
While Not(ve Is Nothing)
If IsArray(ve.Columnvalues(0)) Then
If flag = "" Then
arr = ve.Columnvalues(0)
Else
arr = ArrayUnique(ArrayAppend(arr, ve.Columnvalues(0)))
End If
Else
'error if arr is not already an array
arr = ArrayUnique(ArrayAppend(arr, ve.Columnvalues(0)))
End If
flag = "1"
Set ve = ecl.Getnextentry(ve)
Wend
Anyone know a faster way? It must not be written in LotusScript, actually I would prefer Java, JS or SSJS.
Idea 1: You can use the NotesViewNavigator class, and call the getFirst() and getNextCategory() methods. This should be faster than walking all the entries.
Idea 2: You can use NotesSession.Evaluate() with a formula that does an #Unique on #DbColumn for the first column of view. That should bring you back an array, and you can get the ubound of the array. Formulas tend to be very fast, but evaluate() has to compile them first, so I don't know if this will be faster or not. The disadvantage of this approach is that for very large views, this could exceed formula language's size limits. But if it does prove to be faster, you could catch the exception and fall-back to the slower method of iterating.
Richard's response is perfect!
For a java version it's almost the same:
see the Domino help for getNextCategory the given example below ViewNavigator really answer your need: link here
The evaluate method is also available in java Session