Tools.Mustache

The Tools.Mustache provider enables you to write a Luminesce query that applies Mustache templating to a dataset.

You can use this provider in conjunction with other providers to return data in Mustache templating, see example 4.

Basic usage

@data = select <column> from <some-provider> where <filter-expression>;

@mustache_txt =
use Tools.Mustache with @data
{{#@data}}
  {{<column>}}
{{/@data}}
enduse;

select * from @mustache_txt

Input tables

Tools.Mustache can take in different kinds of variables and outputs a table of data which can take various forms:

@@data = select <some-data>;

@mustache_txt = 
use Tools.Mustache with @@data
<optional-text> {{@@data}} 
<optional-text>
enduse;

select * from @mustache_txt

@data = select <column> from <dataset>;

@mustache_txt = 
use Tools.Mustache with @data
{{#@data}}
 {{<column>}}
{{/@data}}
enduse;

select * from @mustache_txt

@data = select <some-data> as <some-name>,
<other-data> as <other-name>;
   
@partials =
select '' as Name, '' as Template where 1 = 2
--required, this just has 
the effect of creating

 two columns 
union all
values
    ('<some-string>', '{{<some-name>} 
<optional-text> 
{{<other-name>}}')
;

@mustache_txt = 
use Tools.Mustache with @partials, @data
{{#@data}}
 {{><some-string>}}
{{/@data}}
<optional-text>
enduse;
    
select * from @mustache_txt

@foreach = select <column>
[..., <another-column>]
 from <dataset>;

@mustache_txt = 
use Tools.Mustache with @@foreach
{{<column>}} <optional-text> 
{{<another-column>}}
enduse;

select * from @mustache_txt

Examples

Example 1: Applying Mustache templating to some data

In this example, we use a simple scalar variable with Tools.Mustache to return a table of data with one column and one row which contains our completed Mustache template.

@@txt = select 'just like this';

@mustache_txt = 
use Tools.Mustache with @@txt
You can use Mustache templating {{@@txt}}
enduse;

select * from @mustache_txt

The table of data returned looks like this:

Example 2: Creating a Mustache template with a table of data

In this example, we create an input table of data which we use with Tools.Mustache to create a Mustache template.

@data = select 'this' as SomeText, 'that' as MoreText, 10 as SomeNumber;
    
@mustache_txt = 
use Tools.Mustache with @data
{{#@data}}
  You can use {{SomeText}} and {{MoreText}} in Mustache templating.
  And even {{SomeNumber}}!
{{/@data}}
enduse;

select * from @mustache_txt

The table of data returned by the query looks like this, with the Mustache template populated with values:

Example 3: Creating a reusable partial Mustache template

You can use a special kind of variable called @partials in your query to define a reusable partial Mustache template which you could use, for example, to create custom views that output a populated Mustache template.

In this example, we create a table of data and populate a @partials variable with the required special syntax. We then use both variables with the Tools.Mustache provider to return a single cell table of data.

@some_data = select 'x' as SomeText, 'y' as MoreText, 4 as SomeNumber;
   
@partials =
select '' as Name, '' as Template where 1 = 2 -- required, this just has the effect of creating two columns 
union all
values
    ('XRow', '{{SomeText}} : {{SomeNumber}} on {{MoreText}}'),
    ('YRow', '{{MoreTxt}}')
;

@mustache_txt = 
use Tools.Mustache with @partials, @some_data
{{#@some_data}}
 {{>XRow}}
{{/@some_data}}
and
{{#@some_data}}
 {{>YRow}}
{{/@some_data}}
enduse;
    
select * from @mustache_txt

The table of data returned by the query looks like this, with the partial template populated with data from our @some_data variable, all within the larger Mustache template:

Example 4: Creating a Mustache template which outputs multiple rows

In this example, we use a special kind of variable called @foreach with the Tools.Mustache provider to return all columns and rows in the table, plus an additional column containing a populated Mustache template for each row.

@foreach = select distinct TableName, FieldName, DataType from Sys.Field;
    
@mustache_txt = 
use Tools.Mustache with @foreach
{{TableName}}.{{FieldName}} -> {{DataType}}
enduse;

select * from @mustache_txt

The first ten rows of the table of data returned by the query looks like this:

Example 5: Creating a Mustache template which outputs a nested table

In this example, we first define a @foreach variable which uses the group_concat aggregate function with a data field. This variable is then used with Tools.Mustache to create a Mustache template that outputs a nested table in an additional column.

Note the specific syntax used in @mustache_txt. When constructing the Mustache message, AsTable is appended to the column we want to format as a nested table. Within the column which is to become a nested table, fields are split on , and each field is referred to by its order number e.g., {{1}}, {{2}}.

@foreach = select
TableName,
group_concat(FieldName) filter (where FieldType = 'Column') as Columns
from Sys.Field
group by TableName;
    
@mustache_txt = 
use Tools.Mustache with @foreach
{{TableName}}:
{{#ColumnsAsTable}}
  {{1}}
{{/ColumnsAsTable}}
enduse;

select * from @mustache_txt

The first ten rows of the table of data returned by the query looks like this: