petrzjunior / odata-filter-to-ast

Simple NodeJS OData $filter query parser.

odata-filter-to-ast

Simple OData query parser with zero dependencies.

Usage

$ npm install odata-filter-to-ast

Usage in code:

import {parseFilter, parseOrderBy} from 'odata-filter-to-ast';

parseFilter(`Name gt "Milk" or Price lt -2.55 or Size ne 3`);
parseOrderBy(`age,sum(height,width) desc`);

Result:

{
	type: 'orExpr',
	left: {
		type: 'gtExpr',
		left: {
			type: 'memberExpr',
			value: 'Name',
		},
		right: {
			type: 'primitive',
			value: 'Milk'
		},
	},
	right: {
		type: 'orExpr',
		left: {
			type: 'ltExpr',
			left: {
				type: 'memberExpr',
				value: 'Price',
			},
			right: {
				type: 'primitive',
				value: -2.55
			}
		},
		right: {
			type: 'neExpr',
			left: {
				type: 'memberExpr',
				value: 'Size',
			},
			right: {
				type: 'primitive',
				value: 3
			}
		}
	}
}
[
	{
		type: 'orderByItem',
		expr: {
			type: 'memberExpr',
			value: 'age',
		},
		dir: 'asc',
	},
	{
		type: 'orderByItem',
		expr: {
			type: 'functionExpr',
			name: 'sum',
			arguments: [
				{
					type: 'memberExpr',
					value: 'height',
				},
				{
					type: 'memberExpr',
					value: 'width',
				},
			],
		},
		dir: 'desc',
	},
]

Supported constructs

The following construct from OData specification are supported:

• JS primitives -42, 3.14, 6.022e23, "string", true, false, null
• field identifiers iDenT_iFi3r
• heterogeneous arrays ["a","r","r","a","y",7,false,null]
• primitive relations eq, ne, gt, gt, lt, le
• array relation in
• boolean conjunctions and, or
• operator priority grouping ( ... )
• function calls includes(Name,"Joe")
• sort directions asc, desc

Related

• Parser built using Peggy and TS PEG.js
• Grammar inspired by the OData specification and the OData ABNF Construction Rules

odata-filter-to-ast's Issues

String quotation

The OData specification mandates string literal quotation using ', but this repo uses " for literal quotation. OData uses " for identifier quotation.

I'd introduce an issue or PR to make this library OData conformant, but it would break all the dependent projects.

Maybe after increasing the major version? Maybe just adding a warning to the readme? Maybe supporting both for string literals, and not supporting quoted identifiers?

I suspect that there are more inconsistencies with the OData specification than that, especially the number parsing can be non-conformant.