Module @memberjunction/query-processor

@memberjunction/query-processor

Shared query template processing for MemberJunction data providers. Handles parameter validation, type conversion, and Nunjucks template rendering for parameterized queries.

Why This Package Exists

MemberJunction's RunQuery system supports parameterized SQL queries using Nunjucks templates (e.g., {{ status | sqlString }}). This package provides the QueryParameterProcessor class that both the SQL Server and PostgreSQL data providers use to:

Validate user-supplied parameters against query definitions
Convert parameter values to the correct types (string, number, boolean, date, array)
Apply platform-aware boolean handling (SQL Server BIT 1/0 vs PostgreSQL native true/false)
Render Nunjucks templates with validated parameters and SQL-safe filters

Platform-Aware Behavior

The processor reads the current platform from RunQuerySQLFilterManager.Instance.Platform and adjusts behavior accordingly:

Feature	SQL Server	PostgreSQL
Boolean values	`1` / `0` (BIT)	`true` / `false`
`sqlBoolean` filter	Returns `1` or `0`	Returns `TRUE` or `FALSE`
`sqlIdentifier` filter	`[name]`	`"name"`
`sqlLikeContains` / `sqlLikeBegins` / `sqlLikeEnds` filters	Escapes `%` and `_` with `[%]` `[_]`	Escapes with `\%` `\_`

The Nunjucks environment is automatically recreated when the platform changes, since filters are baked in at creation time.

Usage

import { QueryParameterProcessor } from '@memberjunction/query-processor';

// Validate parameters against definitions
const validation = QueryParameterProcessor.validateParameters(
  { status: 'Active', limit: '10' },
  query.Parameters
);

if (validation.success) {
  // Process a query template
  const result = QueryParameterProcessor.processQueryTemplate(
    queryInfo,
    userParams,
    platformSpecificSQL // optional override
  );

  if (result.success) {
    // result.processedSQL contains the rendered SQL
    await executeSQL(result.processedSQL);
  }
}

Dependencies

@memberjunction/core - For RunQuerySQLFilterManager, QueryInfo, QueryParameterInfo types
@memberjunction/global - For MJGlobal utilities
nunjucks - Template rendering engine

Classes

QueryParameterProcessor

Interfaces

ParameterValidationResult
QueryProcessingResult
QueryTemplateInput