SPARQLWrapper.Wrapper module

SPARQLWrapper.Wrapper.XML = 'xml'

to be used to set the return format to XML (SPARQL Query Results XML format or RDF/XML, depending on the query type). This is the default.

SPARQLWrapper.Wrapper.JSON = 'json'

to be used to set the return format to JSON.

SPARQLWrapper.Wrapper.JSONLD = 'json-ld'

to be used to set the return format to JSON-LD.

SPARQLWrapper.Wrapper.TURTLE = 'turtle'

to be used to set the return format to Turtle.

SPARQLWrapper.Wrapper.N3 = 'n3'

to be used to set the return format to N3 (for most of the SPARQL services this is equivalent to Turtle).

SPARQLWrapper.Wrapper.RDF = 'rdf'

to be used to set the return RDF Graph.

SPARQLWrapper.Wrapper.RDFXML = 'rdf+xml'

to be used to set the return format to RDF/XML explicitly.

SPARQLWrapper.Wrapper.CSV = 'csv'

to be used to set the return format to CSV

SPARQLWrapper.Wrapper.TSV = 'tsv'

to be used to set the return format to TSV

SPARQLWrapper.Wrapper.GET = 'GET'

to be used to set HTTP method GET. This is the default.

SPARQLWrapper.Wrapper.POST = 'POST'

to be used to set HTTP method POST.

SPARQLWrapper.Wrapper.BASIC = 'BASIC'

to be used to set BASIC HTTP Authentication method.

SPARQLWrapper.Wrapper.DIGEST = 'DIGEST'

to be used to set DIGEST HTTP Authentication method.

SPARQLWrapper.Wrapper.SELECT = 'SELECT'

to be used to set the query type to SELECT. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.CONSTRUCT = 'CONSTRUCT'

to be used to set the query type to CONSTRUCT. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.ASK = 'ASK'

to be used to set the query type to ASK. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.DESCRIBE = 'DESCRIBE'

to be used to set the query type to DESCRIBE. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.INSERT = 'INSERT'

to be used to set the query type to INSERT. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.DELETE = 'DELETE'

to be used to set the query type to DELETE. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.CREATE = 'CREATE'

to be used to set the query type to CREATE. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.CLEAR = 'CLEAR'

to be used to set the query type to CLEAR. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.DROP = 'DROP'

to be used to set the query type to DROP. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.LOAD = 'LOAD'

to be used to set the query type to LOAD. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.COPY = 'COPY'

to be used to set the query type to COPY. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.MOVE = 'MOVE'

to be used to set the query type to MOVE. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.ADD = 'ADD'

to be used to set the query type to ADD. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.URLENCODED = 'urlencoded'

to be used to set URL encode as the encoding method for the request. This is, usually, determined automatically.

SPARQLWrapper.Wrapper.POSTDIRECTLY = 'postdirectly'

to be used to set POST directly as the encoding method for the request. This is, usually, determined automatically.

class SPARQLWrapper.Wrapper.SPARQLWrapper(endpoint, updateEndpoint=None, returnFormat='xml', defaultGraph=None, agent='sparqlwrapper 1.8.5 (rdflib.github.io/sparqlwrapper)')[source]

Wrapper around an online access to a SPARQL Web entry point.

The same class instance can be reused for subsequent queries. The values of the base Graph URI, return formats, etc, are retained from one query to the next (in other words, only the query string changes). The instance can also be reset to its initial values using the resetQuery() method.

Variables:
  • endpoint (string) – SPARQL endpoint’s URI.
  • updateEndpoint (string) – SPARQL endpoint’s URI for SPARQL Update operations (if it’s a different one). The default value is None.
  • agent (string) – The User-Agent for the HTTP request header. The default value is an autogenerated string using the SPARQLWrapper version code.
  • _defaultGraph (string) – URI for the default graph. The value can be set either via an explicit call addParameter("default-graph-uri", uri) or as part of the query string. The default value is None.
  • user (string) – The username of the credentials for querying the current endpoint. The value can be set an explicit call setCredentials(). The default value is None.
  • passwd (string) – The password of the credentials for querying the current endpoint. The value can be set an explicit call setCredentials(). The default value is None.
  • http_auth (string) – HTTP Authentication type. The default value is BASIC. Possible values are BASIC or DIGEST. It is used only in case the credentials are set.
  • onlyConneg (boolean) – Option for allowing (or not) only HTTP Content Negotiation (so dismiss the use of HTTP parameters). The default value is False.
  • customHttpHeaders (dict) – Custom HTTP Headers to be included in the request. It is a dictionary where keys are the header field and values are the header values. Important: These headers override previous values (including Content-Type, User-Agent, Accept and Authorization if they are present).
  • timeout (int) – The timeout (in seconds) to use for querying the endpoint.
  • queryString (string) – The SPARQL query text.
  • queryType (string) – The type of SPARQL query (aka SPARQL query form), like CONSTRUCT, SELECT, ASK, DESCRIBE, INSERT, DELETE, CREATE, CLEAR, DROP, LOAD, COPY, MOVE or ADD (constants in this module).
  • returnFormat (string) – The return format. No local check is done, so the parameter is simply sent to the endpoint. Eg, if the value is set to JSON and a construct query is issued, it is up to the endpoint to react or not, this wrapper does not check. The possible values are JSON, XML, TURTLE, N3, RDF, RDFXML, CSV, TSV, JSONLD (constants in this module). The default value is XML.
  • requestMethod (string) – The request method for query or update operations. The possibles values are URL-encoded (URLENCODED) or POST directly (POSTDIRECTLY).
  • method (string) – The invocation method (HTTP verb). The default value is GET, but it can be set to POST.
  • parameters (dict) – The parameters of the request (key/value pairs in a dictionary).
  • _defaultReturnFormat (string) – The default return format. It is used in case the same class instance is reused for subsequent queries.
  • prefix_pattern (re.RegexObject, a compiled regular expression. See the re module of Python) – regular expression used to remove base/prefixes in the process of determining the query type.
  • pattern (re.RegexObject, a compiled regular expression. See the re module of Python) – regular expression used to determine whether a query (without base/prefixes) is of type CONSTRUCT, SELECT, ASK, DESCRIBE, INSERT, DELETE, CREATE, CLEAR, DROP, LOAD, COPY, MOVE or ADD.
  • comments_pattern (re.RegexObject, a compiled regular expression. See the re module of Python) – regular expression used to remove comments from a query.
__init__(endpoint, updateEndpoint=None, returnFormat='xml', defaultGraph=None, agent='sparqlwrapper 1.8.5 (rdflib.github.io/sparqlwrapper)')[source]

Class encapsulating a full SPARQL call.

Parameters:
  • endpoint (string) – SPARQL endpoint’s URI.
  • updateEndpoint (string) – SPARQL endpoint’s URI for update operations (if it’s a different one). The default value is None.
  • returnFormat – The return format. No local check is done, so the parameter is simply sent to the endpoint. Eg, if the value is set to JSON and a construct query is issued, it is up to the endpoint to react or not, this wrapper does not check. The possible values are JSON, XML, TURTLE, N3, RDF, RDFXML, CSV, TSV, JSONLD (constants in this module). The default value is XML.
  • defaultGraph (string) – URI for the default graph. The value can be set either via an explicit call addParameter("default-graph-uri", uri) or as part of the query string. The default value is None.
  • agent (string) – The User-Agent for the HTTP request header. The default value is an autogenerated string using the SPARQLWrapper version number.
resetQuery()[source]

Reset the query, ie, return format, method, query, default or named graph settings, etc, are reset to their default values. This includes the default values for parameters, method, timeout or requestMethod.

setReturnFormat(format)[source]

Set the return format. If the one set is not an allowed value, the setting is ignored.

Parameters:format (string) – Possible values are JSON, XML, TURTLE, N3, RDF, RDFXML, CSV, TSV, JSONLD (constants in this module). All other cases are ignored.
Raises:ValueError – If JSONLD is tried to set and the current instance does not support JSON-LD.
supportsReturnFormat(format)[source]

Check if a return format is supported.

Parameters:format (string) – Possible values are JSON, XML, TURTLE, N3, RDF, RDFXML, CSV, TSV, JSONLD (constants in this module). All other cases are ignored.
Returns:Returns True if the return format is supported, otherwise False.
Return type:bool
setTimeout(timeout)[source]

Set the timeout (in seconds) to use for querying the endpoint.

Parameters:timeout (int) – Timeout in seconds.
setOnlyConneg(onlyConneg)[source]

Set this option for allowing (or not) only HTTP Content Negotiation (so dismiss the use of HTTP parameters).

New in version 1.8.1.

Parameters:onlyConneg (bool) – True if only HTTP Content Negotiation is allowed; False if HTTP parameters are used.
setRequestMethod(method)[source]

Set the internal method to use to perform the request for query or update operations, either URL-encoded (URLENCODED) or POST directly (POSTDIRECTLY). Further details at query operation in SPARQL and update operation in SPARQL Update.

Parameters:method (string) – Possible values are URLENCODED (URL-encoded) or POSTDIRECTLY (POST directly). All other cases are ignored.
addDefaultGraph(uri)[source]

Add a default graph URI.

Deprecated since version 1.6.0: Use addParameter("default-graph-uri", uri) instead of this method.

Parameters:uri (string) – URI of the default graph.
addNamedGraph(uri)[source]

Add a named graph URI.

Deprecated since version 1.6.0: Use addParameter("named-graph-uri", uri) instead of this method.

Parameters:uri (string) – URI of the named graph.
addExtraURITag(key, value)[source]

Some SPARQL endpoints require extra key value pairs. E.g., in virtuoso, one would add should-sponge=soft to the query forcing virtuoso to retrieve graphs that are not stored in its local database. Alias of addParameter() method.

Deprecated since version 1.6.0: Use addParameter(key, value) instead of this method

Parameters:
  • key (string) – key of the query part.
  • value (string) – value of the query part.
addCustomParameter(name, value)[source]

Method is kept for backwards compatibility. Historically, it “replaces” parameters instead of adding.

Deprecated since version 1.6.0: Use addParameter(key, value) instead of this method

Parameters:
  • name (string) – name.
  • value (string) – value.
Returns:

Returns True if the adding has been accomplished, otherwise False.
Return type:

bool
addParameter(name, value)[source]

Some SPARQL endpoints allow extra key value pairs. E.g., in virtuoso, one would add should-sponge=soft to the query forcing virtuoso to retrieve graphs that are not stored in its local database. If the parameter query is tried to be set, this intent is dismissed. Returns a boolean indicating if the set has been accomplished.

Parameters:
  • name (string) – name.
  • value (string) – value.
Returns:

Returns True if the adding has been accomplished, otherwise False.
Return type:

bool
addCustomHttpHeader(httpHeaderName, httpHeaderValue)[source]

Add a custom HTTP header (this method can override all HTTP headers).

Important: Take into account that each previous value for the header field names Content-Type, User-Agent, Accept and Authorization would be overriden if the header field name is present as value of the parameter httpHeaderName.

New in version 1.8.2.

Parameters:
  • httpHeaderName (string) – The header field name.
  • httpHeaderValue (string) – The header field value.
clearCustomHttpHeader(httpHeaderName)[source]

Clear the values of a custom HTTP Header previously set. Returns a boolean indicating if the clearing has been accomplished.

New in version 1.8.2.

Parameters:httpHeaderName (string) – HTTP header name.
Returns:Returns True if the clearing has been accomplished, otherwise False.
Return type:bool
clearParameter(name)[source]

Clear the values of a concrete parameter. Returns a boolean indicating if the clearing has been accomplished.

Parameters:name (string) – name
Returns:Returns True if the clearing has been accomplished, otherwise False.
Return type:bool
setCredentials(user, passwd, realm='SPARQL')[source]

Set the credentials for querying the current endpoint.

Parameters:
  • user (string) – username.
  • passwd (string) – password.
  • realm (string) – realm. Only used for DIGEST authentication. The default value is SPARQL

Changed in version 1.8.3: Added realm parameter.

setHTTPAuth(auth)[source]

Set the HTTP Authentication type. Possible values are BASIC or DIGEST.

Parameters:

auth (string) – auth type.
Raises:
  • TypeError – If the auth parameter is not an string.
  • ValueError – If the auth parameter has not one of the valid values: BASIC or DIGEST.
setQuery(query)[source]

Set the SPARQL query text.

Note

No check is done on the validity of the query (syntax or otherwise) by this module, except for testing the query type (SELECT, ASK, etc). Syntax and validity checking is done by the SPARQL service itself.

Parameters:query (string) – query text.
Raises:TypeError – If the query parameter is not an unicode-string or utf-8 encoded byte-string.
_parseQueryType(query)[source]

Internal method for parsing the SPARQL query and return its type (ie, SELECT, ASK, etc).

Note

The method returns SELECT if nothing is specified. This is just to get all other methods running; in fact, this means that the query is erroneous, because the query must be, according to the SPARQL specification. The SPARQL endpoint should raise an exception (via urllib) for such syntax error.

Parameters:query (string) – query text.
Returns:the type of SPARQL query (aka SPARQL query form).
Return type:string
setMethod(method)[source]

Set the invocation method. By default, this is GET, but can be set to POST.

Parameters:method (string) – should be either GET or POST. Other cases are ignored.
setUseKeepAlive()[source]

Make urllib2 use keep-alive.

Raises:ImportError – when could not be imported keepalive.HTTPHandler.
isSparqlUpdateRequest()[source]

Returns True if SPARQLWrapper is configured for executing SPARQL Update request.

Returns:Returns True if SPARQLWrapper is configured for executing SPARQL Update request.
Return type:bool
isSparqlQueryRequest()[source]

Returns True if SPARQLWrapper is configured for executing SPARQL Query request.

Returns:Returns True if SPARQLWrapper is configured for executing SPARQL Query request.
Return type:bool
_cleanComments(query)[source]

Internal method for returning the query after all occurrence of singleline comments are removed (issues #32 and #77).

Parameters:query (string) – The query.
Returns:the query after all occurrence of singleline comments are removed.
Return type:string
_getRequestEncodedParameters(query=None)[source]

Internal method for getting the request encoded parameters.

Parameters:query (tuple) – a tuple of two items. The first item can be the string query (for SELECT, DESCRIBE, ASK, CONSTRUCT query) or the string update (for SPARQL Update queries, like DELETE or INSERT). The second item of the tuple is the query string itself.
Returns:the request encoded parameters.
Return type:string
_getAcceptHeader()[source]

Internal method for getting the HTTP Accept Header.

See also

Hypertext Transfer Protocol – HTTP/1.1 - Header Field Definitions

_createRequest()[source]

Internal method to create request according a HTTP method. Returns a urllib2.Request object of the urllib2 Python library

Raises:NotImplementedError – If the HTTP authentification method is not one of the valid values: BASIC or DIGEST.
Returns:request a urllib2.Request object of the urllib2 Python library
_query()[source]

Internal method to execute the query. Returns the output of the urllib2.urlopen() method of the urllib2 Python library

Returns:

tuples with the raw request plus the expected format.
Raises:
query()[source]

Execute the query. Exceptions can be raised if either the URI is wrong or the HTTP sends back an error (this is also the case when the query is syntactically incorrect, leading to an HTTP error sent back by the SPARQL endpoint). The usual urllib2 exceptions are raised, which therefore cover possible SPARQL errors, too.

Note that some combinations of return formats and query types may not make sense. For example, a SELECT query with Turtle response is meaningless (the output of a SELECT is not a Graph), or a CONSTRUCT query with JSON output may be a problem because, at the moment, there is no accepted JSON serialization of RDF (let alone one implemented by SPARQL endpoints). In such cases the returned media type of the result is unpredictable and may differ from one SPARQL endpoint implementation to the other. (Endpoints usually fall back to one of the “meaningful” formats, but it is up to the specific implementation to choose which one that is.)

Returns:query result
Return type:QueryResult instance
queryAndConvert()[source]

Macro like method: issue a query and return the converted results.

Returns:the converted query result. See the conversion methods for more details.
class SPARQLWrapper.Wrapper.QueryResult(result)[source]

Wrapper around an a query result. Users should not create instances of this class, it is generated by a SPARQLWrapper.query() call. The results can be converted to various formats, or used directly.

If used directly: the class gives access to the direct HTTP request results response obtained from the call to urllib.urlopen(). It is a file-like object with two additional methods:

  • geturl() to return the URL of the resource retrieved
  • info() that returns the meta-information of the HTTP result as a dictionary-like object.

For convenience, these methods are also available on the QueryResult instance.

The __iter__() and next() methods are also implemented (by mapping them to response). This means that the common idiom for l in obj : do_something_with_line(l) would work, too.

Variables:
__init__(result)[source]
Parameters:result – HTTP response stemming from a SPARQLWrapper.query() call, or a tuple with the expected format: (response, format).
geturl()[source]

Return the URL of the original call.

Returns:URL of the original call.
Return type:string
info()[source]

Return the meta-information of the HTTP result.

Returns:meta-information of the HTTP result.
Return type:dict
next()[source]

Method for the standard iterator.

_convertJSON()[source]

Convert a JSON result into a Python dict. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:dict
_convertXML()[source]

Convert an XML result into a Python dom tree. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:xml.dom.minidom.Document
_convertRDF()[source]

Convert a RDF/XML result into an RDFLib Graph. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:rdflib.graph.Graph
_convertN3()[source]

Convert a RDF Turtle/N3 result into a string. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:string
_convertCSV()[source]

Convert a CSV result into a string. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:string
_convertTSV()[source]

Convert a TSV result into a string. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result.
Return type:string
_convertJSONLD()[source]

Convert a RDF JSON-LD result into an RDFLib Graph. This method can be overwritten in a subclass for a different conversion method.

Returns:converted result
Return type:rdflib.graph.Graph
convert()[source]

Encode the return value depending on the return format:

  • in the case of XML, a DOM top element is returned
  • in the case of JSON, a json conversion will return a dictionary
  • in the case of RDF/XML, the value is converted via RDFLib into a RDFLib Graph instance
  • in the case of JSON-LD, the value is converted via RDFLib into a RDFLib Graph instance
  • in the case of RDF Turtle/N3, a string is returned
  • in the case of CSV/TSV, a string is returned
  • In all other cases the input simply returned.
Returns:the converted query result. See the conversion methods for more details.
_get_responseFormat()[source]

Get the response (return) format. The possible values are: JSON, XML, RDFXML, TURTLE, N3, CSV, TSV, JSONLD. In case there is no Content-Type, None is return. In all other cases, the raw Content-Type is return.

New in version 1.8.3.

Returns:the response format. The possible values are: JSON, XML, RDFXML, TURTLE, N3, CSV, TSV, JSONLD.
Return type:string
print_results(minWidth=None)[source]

This method prints a representation of a QueryResult object that MUST has as response format JSON.

Parameters:minWidth (string) – The minimum width, counting as characters. The default value is None.