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实际上我有一个名为 rdf.py 的代码，它生成 rdf 代码..我想做的是直接将该文件移动到 4store 中。我已将整个代码存储在一个变量中，并希望直接将该变量传递给 4store ..可能吗？

rdf.py 的代码如下。rdf_code 包含生成的整个 rdf 代码

import rdflib
from rdflib.events import Dispatcher, Event
from rdflib.graph import ConjunctiveGraph as Graph
from rdflib import plugin
from rdflib.store import Store, NO_STORE, VALID_STORE
from rdflib.namespace import Namespace
from rdflib.term import Literal
from rdflib.term import URIRef
from tempfile import mkdtemp
from gstudio.models import *
from objectapp.models import *
from reversion.models import Version
from optparse import make_option

def get_nodetype(name):
    """
    returns the model the id belongs to.  
    """    
    try:
        """ 
        ALGO:     get object id, go to version model, return for the given id.
        """
        node = NID.objects.get(title=str(name))
        # Retrieving only the relevant tupleset for the versioned objects
        vrs = Version.objects.filter(type=0 , object_id=node.id) 
        # Returned value is a list, so splice it .
        vrs =  vrs[0]

    except Error:
        return "The item was not found."

    return vrs.object._meta.module_name   


def rdf_description(name, notation='xml' ):
    """
    Function takes  title of node, and rdf notation.
    """
    valid_formats = ["xml", "n3", "ntriples", "trix"]
    default_graph_uri = "http://gstudio.gnowledge.org/rdfstore"
    configString = "/var/tmp/rdfstore"

    # Get the Sleepycat plugin.
    store = plugin.get('IOMemory', Store)('rdfstore')

    # Open previously created store, or create it if it doesn't exist yet
    graph = Graph(store="IOMemory",
               identifier = URIRef(default_graph_uri))
    path = mkdtemp()
    rt = graph.open(path, create=False)
    if rt == NO_STORE:
    #There is no underlying Sleepycat infrastructure, create it
        graph.open(path, create=True)
    else:
        assert rt == VALID_STORE, "The underlying store is corrupt"

    # Now we'll add some triples to the graph & commit the changes
   # rdflib = Namespace('http://sbox.gnowledge.org/gstudio/')
    graph.bind("gstudio", "http://gnowledge.org/")
    exclusion_fields = ["id", "rght", "node_ptr_id", "image", "lft", "_state", "_altnames_cache", "_tags_cache", "nid_ptr_id", "_mptt_cached_fields"]
    node_type=get_nodetype(name)
    if (node_type=='gbobject'):
        node=Gbobject.objects.get(title=name)
    elif (node_type=='objecttype'):
        node=Objecttype.objects.get(title=name)
    elif (node_type=='metatype'):
        node=Metatype.objects.get(title=name)
    elif (node_type=='attributetype'):
        node=Attributetype.objects.get(title=name)
    elif (node_type=='relationtype'):
        node=Relationtype.objects.get(title=name)
    elif (node_type=='attribute'):
        node=Attribute.objects.get(title=name)
    elif (node_type=='complement'):
        node=Complement.objects.get(title=name)
    elif (node_type=='union'):
        node=Union.objects.get(title=name)
    elif (node_type=='intersection'):
        node=Intersection.objects.get(title=name)
    elif (node_type=='expression'):
        node=Expression.objects.get(title=name)
    elif (node_type=='processtype'):
        node=Processtype.objects.get(title=name)
    elif (node_type=='systemtype'):
        node=Systemtype.objects.get(title=name)

    node_url=node.get_absolute_url()
    site_add= node.sites.all() 
    a = site_add[0] 
    host_name =a.name
    #host_name=name
    link='http://'
    #Concatenating the above variables will give the url address.

    url_add=link+host_name+node_url
    rdflib = Namespace(url_add)
 # node=Objecttype.objects.get(title=name)

    node_dict=node.__dict__

    subject=str(node_dict['id'])
    for key in node_dict:
        if key not in exclusion_fields:
            predicate=str(key)
            pobject=str(node_dict[predicate])
            graph.add((rdflib[subject], rdflib[predicate], Literal(pobject)))

    rdf_code= graph.serialize(format=notation)

    # print out all the triples in the graph
    for subject, predicate, object in graph:
        print subject, predicate, object

    graph.commit()
    print rdf_code
    graph.close()

我可以直接将 rdf_code 传递给 4store...如果是，那么如何？

4

1 回答 1

2

最简单的方法是将该图转换ntriples为http://yourhost:port/data/GRAPH_URI. 如果您执行 anHTTP POST然后三元组将附加到由 表示的现有图表中GRAPH_URI。如果您执行 HTTP PUT，则当前图表将被替换。如果图表不存在，那么无论您是POST还是PUT.

以这个函数为例：

def assert4s(data,epr,graph,contenttype,flush=False):
    try:
        params = urllib.urlencode({'graph': graph,
                                   'data': data,
                                   'mime-type' : contenttype })
        opener = urllib2.build_opener(urllib2.HTTPHandler)
        request = urllib2.Request(epr,params)
        request.get_method = lambda: ('PUT' if flush else 'POST')
        url = opener.open(request)
        return url.read()
    except Exception, e:
        raise e

如果您有以下数据：

triples = """<a> <b> <c> .
<d> <e> <f> .
"""

您可以执行以下调用：

assert4s(triples,
         "http://yourhost:port/data/",
         "http://some.org/graph/id",
         "application/x-turtle")

编辑

我之前的回答假设您使用的是 4s-httpd 服务器。您可以使用以下命令在 4store 中启动 SPARQL 服务器4s-httpd -p PORT kb_name。运行此程序后，您可以将以下服务用于：

4store SPARQLServer文档非常完整。

于 2012-03-26T16:44:37.887 回答