How to edit my dashboard to ignore null fields not selected in a checkbox?

[sperl]

In my dashboard, I have a set of values I am trying to select via checkboxes. However - I may only have values in one of the checkbox lists.

If any of the inputs are null, the search is malformed, and doesn't work. How can I either ignore the NULL field, or merge the results cleanly to search?

<form>
  <label>Dashboard</label>
  <description>Dashboard</description>
  <fieldset submitButton="true">
    <input type="time" token="field1">
      <label></label>
      <default>
        <earliest>@d</earliest>
        <latest>now</latest>
      </default>
    </input>
    <input type="checkbox" token="field2">
      <label>NY Hosts</label>
      <choice value="aa">aa</choice>
      <choice value="bb">bb</choice>
      <delimiter> OR </delimiter>
      <valuePrefix>Host=</valuePrefix>
    </input>
    <input type="checkbox" token="field3">
      <label>UK Hosts</label>
      <choice value="cc">cc</choice>
      <choice value="dd">dd</choice>
      <choice value="ee">ee</choice>
      <delimiter> OR </delimiter>
      <valuePrefix>Host=</valuePrefix>
    </input>
    <input type="checkbox" token="field4">
      <label>HK Hosts</label>
      <choice value="ff">ff</choice>
      <choice value="gg">gg</choice>
      <delimiter> OR </delimiter>
      <valuePrefix>Host=</valuePrefix>
    </input>
  </fieldset>
  <row>
    <panel>
      <chart>
        <title>Graph1</title>
        <search>
          <query>index=index  $field2$ OR $field3$ OR $field4$ |timechart min(Value) by Host limit=0</query>
          <earliest>$field1.earliest$</earliest>
          <latest>$field1.latest$</latest>
        </search>
</chart>
</panel>
</row>

[rjthibod]

There is no workaround to your problem (the token value for a checkbox group is always undefined if you have no values selected) without using a different type of input and/or using a complicated JavaScript filtering mechanism.

One work around would be using a multiselect input. I would suggest consolidating all of the options into one input, and you could prepend the values with the location prefix. The result would look like the following.

     <input searchWhenChanged="false" token="host_filter" type="multiselect">
       <choice value="*">All</choice>
       <choice value="aa">NY: aa</choice>
       <choice value="bb">NY: bb</choice>
       <choice value="cc">UK: cc</choice>
       <choice value="dd">UK: dd</choice>
       <choice value="ee">UK: ee</choice>
       <choice value="ff">HK: ff</choice>
       <choice value="gg">HK: gg</choice>
       <delimiter> OR </delimiter>
       <valuePrefix>Host="</valuePrefix>
       <valueSuffix>"</valueSuffix>
       <prefix>(</prefix>
       <suffix>)</suffix>
       <default>*</default>
     </input>

And then using it in the search like this

index=index $host_filter$ |timechart min(Value) by Host limit=0</query>

[sperl]

Thank you - is there a way to put the various types in different columns?

I trimmed this for posting, but I can have 6-12 items in each of the multi-select lists, so when it appears as one long column - it becomes very unwieldy.

In other searches I saw using a module name="ValueSetter", but that appeared to be a quite different format than the dashboard xml I'm familiar with.

[rjthibod]

It is possible to split up, but things will get much more complicated. The issue is there is no clean way to specify "None" for one location/region without adding some specialized filtering. What you would have to do is something like this.

      <input searchWhenChanged="false" token="host_filter_ny" type="multiselect">
        <label>NY Hosts</label>
        <choice value="!!!none!!!">None</choice>
        <choice value="aa">aa</choice>
        <choice value="bb">bb</choice>
        <delimiter>;</delimiter>
      </input>
      <input searchWhenChanged="false" token="host_filter_uk" type="multiselect">
        <label>UK Hosts</label>
        <choice value="!!!none!!!">None</choice>
        <choice value="cc">cc</choice>
        <choice value="dd">dd</choice>
        <choice value="ee">ee</choice>
        <delimiter>;</delimiter>
      </input>
      <input searchWhenChanged="false" token="host_filter_hk" type="multiselect">
        <label>HK Hosts</label>
        <choice value="!!!none!!!">None</choice>
        <choice value="ff">ff</choice>
        <choice value="gg">gg</choice>
        <delimiter>;</delimiter>
      </input>

And then specialized logic to filter out any inputs if it includes the None option

index=index 
[
    | gentimes start=-1 
    | eval hostny = "$host_filter_ny$"
    | eval hostuk = "$host_filter_uky$"" 
    | eval hosthk = "$host_filter_hk$"
    | table host* 
    | eval hostny = if(match(hostny,"!none!"), null(), hostny) 
    | eval hostuk = if(match(hostuk,"!none!"), null(), hostuk) 
    | eval hosthk = if(match(hosthk,"!none!"), null(), hosthk) 
    | stats values(*) as * 
    | transpose 
    | rename "row 1" as host 
    | makemv host delim=";" 
    | stats values(host) as Host
] 
| timechart min(Value) by Host limit=0