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Dynamically create a TW object in IBM BPM

I am using IBM BPM 8.6
I have an input string as follows:
"\"RECORD_CONTACT\":\"Maram\" , \"DRUG\":\"Panadol\"
In a script on server side, I want to dynamically create a business object like this:
tw.local.recordContact = Maram;
tw.local.drug = Panadol;
How can I dynamically create the business object?

There are a few problems with your request. The first is that you are not creating a business object, you are creating variables. In IBM BPM the variables have to be declared at design time or you will get an error, so invoking attempting to call something like -
tw.local.myVariable = 'Bob';
Will throw an exception if tw.local.myVariable has not been declared. Base on your other question you asked here (link), I'm going to assume you actually have an ANY variable declared called "return" so that
tw.local.return.myVariable = 'Bob'
will work. Given that I based on Sven's answer I think something like the following will work (you will need to validate)
var str = "\"RECORD_CONTACT\":\"Maram\" , \"DRUG\":\"Panadol\"";
var jsonStr = "{" + str.replace(/\\\"/g,'\"') + "}";
var tempValue = JSON.parse(jsonStr);
var keyArray = Object.keys(tempValue);
var valueArray = Object.values(tempValue);
for(var keyCount=0; keyCount<keyArray.length; keyCount++{
var evalString = "tw.local.return."+keyArray[keyCount]+"="+valueArray[keyCount];
eval(evalString);
}
I'll note that doing this is a very bad idea as it would be very brittle code and that using eval() in this manner opens you up to all sorts of possible exploits. It will also fail badly if the value for one of the keys is not a simple type.
-Andrew Paier

One should know what you are going to do with dynamically created Business Objects (BO) to answer you better. Like a very generic way would be - creating JSON object instead of BO.
But if you want to stick with BO then this is only possible when you know all the BO structure (schema) beforehand during design time.
var str = "\"RECORD_CONTACT\":\"Maram\" , \"DRUG\":\"Panadol\"";
vat objArray = str.split("reg ex to split each object string")
foreach (obj in objArray ){
if(obj.indexOf( "RECORD_CONTACT")!=-1)
tw.local.recordContact = new tw.object.RECORD_CONTACT();
//below goes code get value of each attribute of BPM from string
}
else if(obj.indexOf( "DRUG")!=-1){
//similar code to create BO DRUG
}
Don't forget to create BO before using those :)

How do I pass a Java Map<Long, Integer> into scala-play?

In my play framework project I have a confirmed functional Java map of the form Java that is passed to a html page home.scala.html
The map variable is passed in as other (working) variables are, at the top of the page:
#(workingVar1: String, workingVar2: Int, mapVar: Map[Long, Integer])
But developer tools in google chrome highlights this part of the javascript (embedded in home.scala.html's head):
var myMap = #mapVar;
With the error Uncaught SyntaxError: Unexpected token =
So none of the javascript works. What is the correct way to pass this map in?

You can use Java/Scala variables in Twirl Scala templates and both are executed on the server side.
Now on server side Twirl engine translates Java object to something (which probably isn't what you want) and in this form is passed to client, and then this JavaScript is executed.
You want to make sure that client will receive valid JavaScript code.
To assign proper value, you will have to mix some JSON libraries, which will help you assign value in a proper way.
Eg. on the controller side:
...
Map<Long, Integer> map = new HashMap<>();
map.put(1L, 2);
map.put(3L, 3);
String yourMap = Json.stringify(Json.toJson(map));
Now you want to pass yourMap to view, and then you will assign to myMap
using #Html as we want it as raw content fragment:
#(workingVar1: String, workingVar2: Int, mapVar: String)
var myMap = #Html(mapVar);
Try and let me know if it helped.

An inelegant but functional solution is as follows:
Bring in the Java Map as a string:
var stringMap = "#mapVar";
Removes the braces and spaces inserted into the string unnecessarily
stringMap = stringMap.replace(/{/g,'');
stringMap = stringMap.replace(/}/g,'');
stringMap = stringMap.replace(/ /g,'');
Split the mapString by , and for every pair split again by =, extracting keys and values as you go. These will need to be parsed to their correct data-types before adding to a javascript array jsArr:
var pairArray = mapString.split(",");
pairArray.forEach(function(pair) {
var values = pair.split("=");
var longString = values[0];
var intString = values[1];
var myLong = parseFloat(longString);
var myInt = parseInt(intString);
jsArr.myLong = myInt;
}
Where jsArr has been defined previously.

Trying to parse special characters to retrieve JSON element in JavaScript

I need help on a university project I am working on with NodeRed. I am integrating a JSON API in JS (NodeRed) and hit a roadblock. Here's the kind of JSON I'm retrieving:
{"#SpeciesCode":"NO2","#MeasurementDateGMT":"2016-04-04 00:00:00","#Value":"58.2"}
That "#" sign is really giving me all sorts of troubles because wether I use JSON.parse or stringify or escaping, it is either telling me " Unexpected token #" or just "undefined value".
Here is the code I'm working with:
var body = msg.payload;
var bodyParsed = JSON.parse(body);
var data = bodyParsed.AirQualityData.Data;
var valueStr="#Value";
var value=JSON.stringify(valueStr);
var valueParsed=JSON.parse(value);
var element = data[0].valueParsed;
return {payload:element};
If you want to have a go at it, here's the URL to the data: http://api.erg.kcl.ac.uk/AirQuality/Data/Site/SiteCode=WM6/StartDate=2016-04-04/EndDate=2016-05-04/Json
[UPDATE: SOLVED] Thanks to jcubic who provided the solution in the comments below:
to access property using a variable you need to use bracket notation:
var element = data[0][valueParsed]; also you don't need to stringify and parse #value just use data[0]["#Value"]
So the new code is
var body = msg.payload;
var bodyParsed = JSON.parse(body);
var data = bodyParsed.AirQualityData.Data;
var element = data[0]["#Value"];
return {payload:element};

How to store and retrieve JSON data into local storage?

I have this code:
var string = '{"items":[{"Desc":"Item1"},{"Desc":"Item2"}]}';
localStorage.setItem('added-items', JSON.stringify(string));
This code will use localStorage.
Here is now the code to get the stored data:
var retrievedObject = localStorage.getItem('added-items');
My problem now is, how can i get the size of the data items? answer must be 2.
How can i get the "Item1" and "Item2"?
I tried retrievedObject[0][0] but it is not working.
And how to add data on it?
so it will be
{"items":[{"Desc":"Item1"},{"Desc":"Item2"},{"Desc":"Item3"}]}
Can I use JSON.stringify?

var string = '{"items":[{"Desc":"Item1"},{"Desc":"Item2"}]}';
localStorage.setItem('added-items', JSON.stringify(string));
stringify means, take an object and return its presentation as a string.
What you have, is already a string and not a JSON object.
The opposite is JSON.parse which takes a string and turns it into an object.
Neither of them have anything to do with getting the size of an array. When properly coding JavaScript you almost never use JSON.parse or JSON.stringify. Only if serialization is explicitly wanted.
Use length for the size of the array:
var obj = {"items":[{"Desc":"Item1"},{"Desc":"Item2"},{"Desc":"Item3"}]}
console.debug(obj.items.length);

// THIS IS ALREADY STRINGIFIED
var string = '{"items":[{"Desc":"Item1"},{"Desc":"Item2"}]}';
// DO NOT STRINGIFY AGAIN WHEN WRITING TO LOCAL STORAGE
localStorage.setItem('added-items', string);
// READ STRING FROM LOCAL STORAGE
var retrievedObject = localStorage.getItem('added-items');
// CONVERT STRING TO REGULAR JS OBJECT
var parsedObject = JSON.parse(retrievedObject);
// ACCESS DATA
console.log(parsedObject.items[0].Desc);

To bring clarity to future people that may stumble across this question and found the accepted answer to not be everything you hoped and dreamed for:
I've extended the question so that the user may either want to input a string or JSON into localStorage.
Included are two functions, AddToLocalStorage(data) and GetFromLocalStorage(key).
With AddToLocalStorage(data), if your input is not a string (such as JSON), then it will be converted into one.
GetFromLocalStorage(key) retrieves the data from localStorage of said key
The end of the script shows an example of how to examine and alter the data within JSON. Because it is a combination of objects and array, one must use a combination of . and [] where they are applicable.
var string = '{"items":[{"Desc":"Item1"},{"Desc":"Item2"}]}';
var json = {"items":[{"Desc":"Item1"},{"Desc":"Item2"},{"firstName":"John"},{"lastName":"Smith"}]};
localStorage.setItem('added-items', AddToLocalStorage(string));
localStorage.setItem('added-items', AddToLocalStorage(json));
// this function converts JSON into string to be entered into localStorage
function AddToLocalStorage(data) {
if (typeof data != "string") {data = JSON.stringify(data);}
return data;
}
// this function gets string from localStorage and converts it into JSON
function GetFromLocalStorage(key) {
return JSON.parse(localStorage.getItem(key));
}
var myData = GetFromLocalStorage("added-items");
console.log(myData.items[2].firstName) // "John"
myData.items[2].firstName = ["John","Elizabeth"];
myData.items[2].lastName = ["Smith","Howard"];
console.log(myData.items[2]) // {"firstName":["John","Elizabeth"],"lastName":["Smith","Howard"]}
console.log(myData.items.length) // 4

JSON.parse is definitely the best way to create an object but I just want to add if that doesn't work (because of lack of support), obj = eval('(' + str + ')'); should work. I've had a problem with a HTML to PDF converter in the past that didn't include JSON.parse and eval did the trick. Try JSON.parse first.
Access your object: obj.items[0].Desc;

var object = Json.parse(retrievedObject);
Now you can access it just like an array
https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse
If you need more help i have some previous code where i am reading Json from local storage and making a form from that json. This code will help in understanding how to traverse that array
Json stored in localstorage
{"form":[{"element":"input", "type":"text","name":"name","value":"value","min":"2","max":"10"}]}
JavaScript to read that json
function readJson(){
if(!form_created){
add_form();
}
var fetched_json = localStorage.getItem("json");
var obj=JSON.parse(fetched_json);
for(var i=0; i<obj.form.length;i++){
var input = document.createElement(obj.form[i].element);
input.name = obj.form[i].name;
input.value = obj.form[i].value;
input.type = obj.form[i].type;
input.dataset.min = obj.form[i].min;
input.dataset.max = obj.form[i].max;
input.dataset.optional = obj.form[i].optional;
form.insertBefore (input,form.lastChild);
}
alert(obj.form[0].name);
}

Delete multiple documents

The following code is working but extremely slow. Up till the search function all goes well. First, the search function returns a sequence and not an array (why?!). Second, the array consists of nodes and I need URI's for the delete. And third, the deleteDocument function takes a string and not an array of URI's.
What would be the better way to do this? I need to delete year+ old documents.
Here I use xdmp.log in stead of document.delete just te be safe.
var now = new Date();
var yearBack = now.setDate(now.getDate() - 365);
var date = new Date(yearBack);
var b = cts.jsonPropertyRangeQuery("Dtm", "<", date);
var c = cts.search(b, ['unfiltered']).toArray();
for (i=0; i<fn.count(c); i++) {
xdmp.log(fn.documentUri(c[i]), "info");
};

Doing the same with cts.uris:
var now = new Date();
var yearBack = now.setDate(now.getDate() - 365);
var date = new Date(yearBack);
var b = cts.jsonPropertyRangeQuery("Dtm", "<", date);
var c = cts.uris("", [], b);
while (true) {
var uri = c.next();
if (uri.done == true){
break;
}
xdmp.log(uri.value, "info");
}
HTH!

Using toArray will work but is most likely were your slowness is. The cts.search() function returns an iterator. So All you have to do is loop over it and do your deleting until there is no more items in it. Also You might want to limit your search to 1,000 items. A transaction with a large number of deletes will take a while and might time out.
Here is an example of looping over the iterator
var now = new Date();
var yearBack = now.setDate(now.getDate() - 365);
var date = new Date(yearBack);
var b = cts.jsonPropertyRangeQuery("Dtm", "<", date);
var c = cts.search(b, ['unfiltered']);
while (true) {
var doc = c.next();
if (doc.done == true){
break;
}
xdmp.log(fn.documentUri(doc), "info");
}
here is an example if you wanted to limit to the first 1,000.
fn.subsequence(cts.search(b, ['unfiltered']), 1, 1000);

Several things to consider.
1) If you are searching for the purpose of deleting or anything that doesnt require the document body, using a search that returns URIs instead of nodes can be much faster. If that isnt convenient then getting the URI as close to the search expression can achieve similar results. You want to avoid having the server have to fetch and expand the document just to get the URI to delete it.
2) While there is full coverage in the JavaScript API's for all MarkLogic features, the JavaScript API's are based on the same underlying functions that the XQuery API's use. Its useful to understand that, and take a look at the equivalent XQuery API docs to get the big picture. For example Arrays vs Iterators - If the JS search API's returned Arrays it could be a huge performance problem because the underlying code is based on 'lazy evaluation' of sequences. For example a search could return 1 million rows but if you only look at the first one the server can often avoid accessing the remaining 999,999,999 documents. Similarly, as you iterate only the in scope referenced data needs to be in available. If they had to be put into an array then all results would have to be pre-fetched and put put in memory upfront.
3) Always keep in mind that operations which return lists of things may only be bounded by how big your database is. That is why cts.search() and other functions have built in 'pagination'. You should code for that from the start.
By reading the users guides you can get a better understanding of not only how to do something, but how to do it efficiently - or even at all - once your database becomes larger than memory. In general its a good idea to always code for paginated results - it is a lot more efficient and your code will still work just as well after you add 100 docs or a million.
4) take a look at xdmp.nodeUrl https://docs.marklogic.com/xdmp.nodeUri,
This function, unlike fn.documentUri(), will work on any node even if its not document node. If you can put this right next to the search instead of next to the delete then the system can optimize much better. The examples in the JavaScript guide are a good start https://docs.marklogic.com/guide/getting-started/javascript#chapter
In your case I suggest something like this to experiment with both pagination and extracting the URIs without having to expand the documents ..
var uris = []
for (var result of fn.subsequence(cts.search( ... ), 1 , 100 )
uris.push(xdmp.nodeUri(result))
for( i in uris )
xdmp.log( uris[i] )