gremlin-python/src/main/python/radish/utils.py

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from gremlin_python.process.anonymous_traversal import traversal
from gremlin_python.process.graph_traversal import __
from radish import pick


@pick
def create_lookup_v(remote):
    g = traversal().with_(remote)

    # hold a map of name/vertex for use in asserting results
    return g.V().group().by('name').by(__.tail()).next()


@pick
def create_lookup_e(remote):
    g = traversal().with_(remote)

    # hold a map of the "name"/edge for use in asserting results - "name" in this context is in the form of
    # outgoingV-label->incomingV
    edges = {}
    edge_map = g.E().group(). \
        by(__.project('o', 'l', 'i').by(__.out_v().values('name')).by(__.label()).by(__.in_v().values('name'))). \
        by(__.tail()).next()

    for key, value in edge_map.items():
        edges[_get_edge_keys(key)] = value

    return edges


def _get_edge_keys(key_map):
    outV = key_map.get('o')
    label = key_map.get('l')
    inV = key_map.get('i')
    return f'{outV}-{label}->{inV}'


@pick
def create_lookup_vp(remote):
    g = traversal().with_(remote)

    # hold a map of the "name"/vertexproperty for use in asserting results - "name" in this context is in the form of
    # vertexName-propName->propVal where the propVal must be typed according to the gherkin spec. note that the toy
    # graphs only deal in String/Int/Float/Double types so none of the other types are accounted for here.
    vps = {}
    props = g.V().properties().group(). \
        by(__.project('n', 'k', 'v').by(__.element().values('name')).by(__.key()).by(__.value())). \
        by(__.tail()).next()

    for key, value in props.items():
        vps[_get_v_keys(key)] = value

    return vps


# since gremlin-lang doesn't allow lambdas, we are using the same logic as javascript to construct the keys
def _get_v_keys(key_map):
    k = key_map.get('k')
    val = key_map.get('v')
    if k == 'weight':
        val = f'd[{val}].d'
    elif k == 'age' or k == 'since' or k == 'skill':
        val = f'd[{val}].i'
    name = key_map.get('n')

    return f'{name}-{k}->{val}'