ShExJSG

0.8.2 verified Mon Apr 27 auth: no python

ShExJSG is a Python library that provides an abstract syntax tree (AST) for the ShEx 2.0 schema language, built on PyJSG and Antlr. It is used for parsing, validating, and generating ShEx schemas. Current version is 0.8.2, with a history of adaptation to newer rdflib and Python versions.

pip install shexjsg

Common errors

error ModuleNotFoundError: No module named 'shexjsg' ↓

cause The package shexjsg is not installed.

fix

Run: pip install shexjsg

error AttributeError: module 'shexjsg' has no attribute 'ShExJ' ↓

cause Incorrect import path; ShExJ is not a direct attribute.

fix

Use: from shexjsg import ShExJ

Warnings

breaking Version 0.8.0 changed rdflib support from v4 to v5/v6. Code using rdflib 4 may break. ↓

fix Upgrade rdflib to >=5.0.0 or pin shexjsg to 0.7.1.

gotcha ShExJSG depends on PyJSG, which itself generates code. Ensure PyJSG is installed and up-to-date to avoid import errors. ↓

fix Install/upgrade pyjsg: pip install pyjsg --upgrade

Imports

ShExJ
wrong
```
import shexjsg
```
correct
```
from shexjsg import ShExJ
```
ShExJ is the primary schema class; direct import is incorrect.

Schema

wrong

from shexjsg import Schema

correct

from shexjsg.schema import Schema

Schema is located in the schema submodule.

Quickstart

Parses a ShEx schema from a JSON string using ShExJSG.

from shexjsg import ShExJ
from rdflib import Graph
import json

# Create a simple schema
schema_json = '''{
  "@context": "http://www.w3.org/ns/shex.jsonld",
  "type": "Schema",
  "shapes": [
    {
      "id": "http://example.org/FooShape",
      "type": "Shape",
      "expression": {
        "type": "TripleConstraint",
        "predicate": "http://example.org/p",
        "valueExpr": {
          "type": "NodeConstraint",
          "datatype": "http://www.w3.org/2001/XMLSchema#string"
        }
      }
    }
  ]
}'''

# Parse and load schema
schema = ShExJ()
schema.loads(schema_json)
print('Schema loaded successfully')
print(json.dumps(schema.as_dict(), indent=2))