Dynamic AQL query with ES6 literal template

Question

I would like to generate a query dynamically in Foxx. The filter statement would be there or not depend on the request parameter. For example

//Conditionally determine if we should include a filter statement here or not
var var1=true;
getAllEntitiesThatSatisfyTheCondition = db._query(aql `
      For u In ${EntityCollection}
      ${var1 ? `Filter u.prop == ${var1}`:``}
      Return DISTINCT u._id
    `).toArray();

This one would return an error about binding value

syntax error, unexpected bind parameter

How can I construct the query using literal template this way in arango, or I have to use query builder?

There are some (not yet unreleased) changes to the ArangoJS driver that should help you, namely the handling of `undefined` (will be omitted instead of generating a bind variable with no value) and nesting support: https://github.com/arangodb/arangojs/blob/master/CHANGELOG.md — CodeManX, Oct 18 '18 at 14:08
Related: [AQL template in arango Foxx does not work correctly with array](https://stackoverflow.com/questions/52967790/aql-template-in-arango-foxx-does-not-work-correctly-with-array/) (ArangoJS v6.7.0 supports nesting of templates) — CodeManX, Oct 25 '18 at 14:28

score 2 · Accepted Answer · answered Oct 18 '18 at 16:27

2

This works for me on Foxx using Arango 3.3.16:

var test = "1124852" 
const filter = aql.literal(
    test ? `AND v._key == "${test}" ` : ''
  );

then on your query just add

${filter}

answered Oct 18 '18 at 16:27

camba1

1,795
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Goes without saying that literals do not validate the parameters, so use with caution and validate properly to avoid injection – camba1 Oct 18 '18 at 16:30
When I use your suggestion into the exact query I have above, there is a new problem as "AQL: syntax error, unexpected assignment near..." – Loredra L Oct 19 '18 at 07:34
Nevermind, it was the error of using !==. I have accepted your answer – Loredra L Oct 19 '18 at 07:38

score 0 · Answer 2 · answered Oct 20 '18 at 01:15

You can use it like below as well.

var filter = "FILTER a.name=='test'";


var query = `
   for a IN collection1
  "${filter}"
 limit 50
  return a
`;

db._query(query).toArray();

Here the javascript filter variable will be replaced dynamically. Hope this helps.

Dynamic AQL query with ES6 literal template

2 Answers2