# Working on "values" in field to return result **URL:** \ **Category:** Elasticsearch\ **Tags:** painless\ **Created:** [May 28, 2019, 8:30pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190 "2019-05-28T20:30:56Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Dunkirk](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dunkirk](https://discuss.elastic.co/u/Dunkirk)\ **Post date:** [May 28, 2019, 8:30pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/1 "2019-05-28T20:30:56Z")
I'm trying to build a search script that returns true or false based on a strange criteria. One of my fields is a JSON array of strings. For particular records, the first string represents an integer which is a bitfield. I need to 1) get the first element as a string, 2) convert it to an integer, and 3) compare it with a bit index by shifting or masking. Can I do all of this within a painless script, embedded in my query? The API documentation makes me think this is possible, but I can't find a single example which even puts me on paper with this. The "compiler" chokes on the first line of my attempt: ``` def jsonArray = new JSONArray(doc['Tunings.Data'].value); ``` It doesn't like `JSONArray`, which I thought would be available. If I try something like: ``` def vals = new String[] { doc['Tunings.Data'].value }; ``` This passes the compiler, but I can't figure out what I actually have captured in the `vals` variable. I can't figure out how to inspect it. Is it a string? Has it been interpreted as an array? Nothing I try to compare it to equates to true. So, just as just the first step, how would I get the first value of a JSON-array-formatted field like this? "["14765"]" ---
**Author:** ![Dunkirk](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dunkirk](https://discuss.elastic.co/u/Dunkirk)\ **Post date:** [May 28, 2019, 8:44pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/2 "2019-05-28T20:44:44Z")
Note that this evaluates to true, and returns documents: ``` def vals = doc['Tunings.Data'].value; return vals == \"[\\\"3\\\"]\"; ``` So I'm looking for something like this, but the exact syntax eludes me: ``` def vals = new String[] { doc['Tunings.Data'].value }; return vals[0] == \"3\"; ``` I apparently don't have `JSONArrary`... Maybe I can just `gsub` the braces away, and deal with a single string (for my particular case)... ---
**Author:** ![Dunkirk](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dunkirk](https://discuss.elastic.co/u/Dunkirk)\ **Post date:** [May 28, 2019, 8:54pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/3 "2019-05-28T20:54:27Z")
This works: ``` def val = doc['Tunings.Data'].value; def str = val.replace('[', '').replace(']', '').replace('\"', ''); return str == '3'; ``` So now I understand that Elasticsearch is doing no interpretation of double quotes as indicating strings. _Is_ there any way to get Elasticsearch (within or without Painless) to understand a string field formatted as follows as an array of strings? Like: ["0"],["1"],["2"] ---
**Author:** ![spinscale](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/spinscale/32/25011_2.png) [@spinscale](https://discuss.elastic.co/u/spinscale)\ **Post date:** [May 29, 2019, 7:12am UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/4 "2019-05-29T07:12:38Z")
the data returned by `.value` is already a list, so you get access the first element via `.get(0)`. you can use `Integer.valueOf()` to convert it to an int, but then you need to check if the code you want to execute is allowed within painless (it has a restrictive white and blacklisting mechanism). You might want to check the painless docs if you can call those methods you want to call, see [https://www.elastic.co/guide/en/elasticsearch/painless/7.1/painless-api-reference.html](https://www.elastic.co/guide/en/elasticsearch/painless/7.1/painless-api-reference.html) ---
**Author:** ![Dunkirk](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dunkirk](https://discuss.elastic.co/u/Dunkirk)\ **Post date:** [May 29, 2019, 10:45am UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/5 "2019-05-29T10:45:12Z")
When I try to use `doc.get('Tunings.Data').value` or `doc.get('Tunings.Data').get(0)`, my later code chokes with an error like: ``` "lang" : "painless", "caused_by" : { "type" : "number_format_exception", "reason" : "For input string: \"[\"3\"]\"" } ``` So it doesn't seem like either one of those is interpreting my string as an array or list. I mean, I'm assuming that I've formatted my JSON string arrays correctly, with escaped double-quotes surrounding the values. An example line in one of my imported docs looks like this: ``` "Data": "[\"00\",\"01\",\"02\",\"03\",\"04\",\"05\"]", ``` What should that line look like that would allow Elastic to correctly interpret it as an array of strings, so that `doc.get('Tunings.Data').get(0)` gives me the string, "00"? ---
**Author:** ![spinscale](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/spinscale/32/25011_2.png) [@spinscale](https://discuss.elastic.co/u/spinscale)\ **Post date:** [May 29, 2019, 11:37am UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/6 "2019-05-29T11:37:43Z")
providing a fully fledged example for others to reproduce would be super helpful here, otherwise everything else is just guesswork. ---
**Author:** ![Dunkirk](https://avatars.discourse-cdn.com/v4/letter/d/9dc877/32.png) [@Dunkirk](https://discuss.elastic.co/u/Dunkirk)\ **Post date:** [May 29, 2019, 12:31pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/7 "2019-05-29T12:31:01Z")
A full example would be tough. A typical document is 20 MB, and the index schema definition is hundreds of lines long. Ultimately, my question is pretty simple: Given a keyword field which contains a JSON representation of an array of strings, how do I get the first element of that array with Painless? The 2 functions I've tried just seem to return the whole field, and the typical way of handling this in JSON-based types and functions in Java don't seem to be available in the API. ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [June 26, 2019, 12:31pm UTC](https://discuss.elastic.co/t/working-on-values-in-field-to-return-result/183190/8 "2019-06-26T12:31:01Z")
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