Millan is the Stardog whisperer -- a set of parsers for languages used with Stardog (currently SPARQL, Turtle, TriG, Stardog Mapping Syntax 2 (SMS), Stardog Rules Syntax, the Turtle serialization of SHACL, and GraphQL).
- Error-tolerant parsing for W3C-compliant SPARQL and SPARQL with Stardog extensions.
- Error-tolerant parsing for W3C-compliant Turtle
- Error-tolerant parsing for W3C-compliant TriG
- Error-tolerant parsing for Stardog Mapping Syntax 2 (SMS)
- Error-tolerant parsing for Stardog Rules Syntax (SRS)
- Error-tolerant parsing for the Turtle serialization of the W3C Shapes Constraints Language (SHACL)
- Error-tolerant parsing for GraphQL (both the Facebook standard and with Stardog's GraphQL extensions)
- Exported token matchers (regular expressions) and token sets for all of the above languages
- Universally usable (both in nodejs and the browser), either as a single bundle or as only the specific parts you need
- Tested against W3C test suites
- Small and fast
- Written in TypeScript, compiled to JS (with type declarations provided TypeScript)
- Used in production at Stardog in support of Stardog Studio language servers
Simply run:
npm install --save millan
You can then import Millan in Node.js or in the browser, using any preferred module format or bundler.
In Node/CommonJS:
const millan = require('millan');
// or, if you only need some part of millan (e.g., only _one_ of the parsers):
const graphql = require('millan/dist/standalone/millan.graphql');
As an ES module:
import * as millan from 'millan';
// or, if you only need some part of millan (e.g., only _one_ of the parsers):
import { StardogSparqlParser } from 'millan/dist/standalone/millan.sparql';
In the browser, importing everything at once:
<script src="path/to/millan/millan.js"></script>
In the browser, importing only what is needed:
<!-- Here, we first load any shared chunks needed by 'sms' (as indicated by the filename), then the SMS-related Javacript only -->
<script src="path/to/millan/dist/browser/millan.vendors~graphql~shacl~sms~sparql~srs~turtle.js"></script>
<script src="path/to/millan/dist/browser/millan.sms.js"></script>
When used in the browser via script
tags, the API will be exposed on a global millan
variable.
Import Millan or the specific parts of Millan that you need, e.g.:
import { W3SpecSparqlParser } from 'millan';
Parsing a document requires a parser instance, so you should get one:
const sparqlParser = new W3SpecSparqlParser();
Every parser instance has essentially the same API. They are all instances of the Parser base class from chevrotain, and they all implement the IStardogParser interface.
The two parser methods you'll use most often are parse
and tokenize
. Use
tokenize
only when you want the parser instance to lex (tokenize) the
provided text:
sparqlParser.tokenize(`
PREFIX : <http://example.org/ns#>
SELECT *
WHERE { ?x ?y ?z }
`);
Result:
[
{
"image": "PREFIX",
"startOffset": 3,
"endOffset": 8,
"startLine": 2,
"endLine": 2,
"startColumn": 3,
"endColumn": 8,
"tokenTypeIdx": 43,
"tokenType": {
"PATTERN": {},
"tokenTypeIdx": 43,
"CATEGORIES": [],
"categoryMatches": [],
"categoryMatchesMap": {},
"tokenName": "PREFIX",
"isParent": false
}
},
/* . . . */
]
Use parse
when you want the full parsing experience. Note that, because
Millan's parsers are error-tolerant, the parse
method returns an object
that contains both a concrete syntax tree (CST)
and an array of any errors:
sparqlParser.parse(`
PREFIX : <http://example.org/ns#>
SELECT *
WHERE { ?x ?y ?z }
`);
Result:
{
"errors": [],
"cst": {
"name": "SparqlDoc",
"children": {
"Prologue": [
{
"name": "Prologue",
"children": {
"PrefixDecl": [
{
"name": "PrefixDecl",
"children": {
"PREFIX": [
{
"image": "PREFIX",
"startOffset": 3,
"endOffset": 8,
"startLine": 2,
"endLine": 2,
"startColumn": 3,
"endColumn": 8,
"tokenTypeIdx": 43,
"tokenType": {
"PATTERN": {},
"tokenTypeIdx": 43,
"CATEGORIES": [],
"categoryMatches": [],
"categoryMatchesMap": {},
"tokenName": "PREFIX",
"isParent": false
}
}
],
"PNAME_NS": [ /* . . . */ ],
/* . . . etc. . . . */
Helpfully, the name
fields in the CSTs returned by Millan's parsers exactly
match, in nearly every case (we've removed some redundancy), the names of the
rules in the official EBNF for the corresponding grammar (e.g., SparqlDoc
,
Prologue
, PrefixDecl
, etc.).
When there are errors in parsing, Millan's parsers still return a best-effort CST, as well as information including the spot where the error occurred, what the parser expected to find at that spot, what the parser actually found in that spot, the "context" (i.e., the position in the grammar's "rule stack"), and more:
sparqlParser.parse(`
PREFIX : <http://example.org/ns#>
SELECT 1
WHERE { ?x ?y ?z }
`);
Result:
{
"errors": [
{
"name": "NoViableAltException",
"message": "Expecting: one of these possible Token sequences:\n 1. [?foo]\n 2. [?bar]\n 3. [LParen]\n 4. [Star]\nbut found: '1'",
"token": {
"image": "1",
"startOffset": 47,
"endOffset": 47,
"startLine": 3,
"endLine": 3,
"startColumn": 10,
"endColumn": 10,
"tokenTypeIdx": 7,
"tokenType": {
"PATTERN": {},
"tokenTypeIdx": 7,
"CATEGORIES": [],
"categoryMatches": [],
"categoryMatchesMap": {},
"tokenName": "INTEGER",
"isParent": false
}
},
"resyncedTokens": [],
"context": {
"ruleStack": [
"SparqlDoc",
"QueryUnit",
"Query",
"SelectQuery",
"SelectClause"
],
"ruleOccurrenceStack": [
0,
0,
0,
0,
0
]
}
}
],
"cst": {
"name": "SparqlDoc",
"children": {
"Prologue": [
{
"name": "Prologue",
"children": {
"PrefixDecl": [
{
"name": "PrefixDecl",
/* . . . etc. . . . */
Check out our comprehensive API docs for more information.
After cloning the repo, in the project's root, run:
yarn install
All development-relevant code, including tests, is located in the repo's src/
directory. All of this code should be written in TypeScript. After making
changes, you will want to run our test scripts (run by Jest), like so:
yarn test
Stylistic conventions and formatting are enforced via tslint
and prettier
,
which means you don't really need to worry about those things yourself
(both the linter and prettier
will check and format your code automatically
on any commit). If you'd like to force prettier
to format your code (a la
gofmt
), just run:
yarn format
To have the project run a lint check, tests, and compilation while you make changes, simply run (and leave running):
yarn dev
The preferred way of making a pull request is as follows:
- Create an issue for the PR, if there isn't one already.
- Branch off of master with a branch name that begins with either 'feature/'
or 'bug/', and make the rest of the branch name include the issue number and
a brief description of the branch (e.g.,
bug/104-turtle-prefix-error
). - Do your work on that branch, push the branch when it is ready, and create a PR.
If you don't have contributor rights, you will need to fork the repo before doing steps 2 and 3, and then submit the PR from your fork.
Be sure to run yarn docs
before submitting your PR, so that our type docs are
updated accordingly.
Copyright 2018 Stardog Union
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.