Examples with OutputVariable org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable used on opensource projects

Example 1 with OutputVariable

use of org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable in project wikidata-query-rdf by wikimedia.

the class MWApiServiceCall method parseResponse.

/**
 * Parse XML response from WM API.
 *
 * @param responseStream Response body as stream
 * @param binding Current binding set.
 * @return Set of resulting bindings, or null if none found.
 * @throws SAXException on error
 * @throws IOException on error
 * @throws XPathExpressionException on error
 */
public ResultWithContinue parseResponse(InputStream responseStream, IBindingSet binding) throws SAXException, IOException, XPathExpressionException {
    if (outputVars.isEmpty()) {
        return null;
    }
    Document doc = docBuilder.get().parse(responseStream);
    XPath path = xpath.get();
    ImmutableMap<String, String> searchContinue = parseContinue(doc, path);
    // FIXME: we're re-compiling it each time. Should probably do it only
    // once per template.
    // Note though that XPathExpression is not thread-safe. Maybe use ThreadLocal?
    XPathExpression itemsXPath = path.compile(template.getItemsPath());
    NodeList nodes = (NodeList) itemsXPath.evaluate(doc, XPathConstants.NODESET);
    if (nodes.getLength() == 0) {
        return null;
    }
    IBindingSet[] results = new IBindingSet[nodes.getLength()];
    final Map<OutputVariable, XPathExpression> compiledVars = new HashMap<>();
    // Thanks, Oracle!
    for (OutputVariable var : outputVars) {
        compiledVars.put(var, xpath.get().compile(var.getPath()));
    }
    for (int i = 0; i < nodes.getLength(); i++) {
        final Node node = nodes.item(i);
        results[i] = binding.copy(null);
        for (Map.Entry<OutputVariable, XPathExpression> var : compiledVars.entrySet()) {
            final IConstant constant;
            if (var.getKey().isOrdinal()) {
                constant = makeConstant(lexiconRelation.getValueFactory(), i);
                results[i].set(var.getKey().getVar(), constant);
                continue;
            }
            final Node value = (Node) var.getValue().evaluate(node, XPathConstants.NODE);
            if (value != null && value.getNodeValue() != null) {
                if (var.getKey().isURI()) {
                    constant = makeConstant(lexiconRelation.getValueFactory(), var.getKey().getURI(value.getNodeValue()));
                } else {
                    constant = makeConstant(lexiconRelation.getValueFactory(), value.getNodeValue());
                }
                results[i].set(var.getKey().getVar(), constant);
            }
        }
    }
    return new ResultWithContinue(results, searchContinue);
}

Example 2 with OutputVariable

use of org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable in project wikidata-query-rdf by wikimedia.

the class MWApiServiceCallUnitTest method testEmptyVars.

@Test
public void testEmptyVars() throws Exception {
    List<OutputVariable> outputVars = Lists.newArrayList();
    InputStream responseStream = new ByteArrayInputStream("not even xml".getBytes("UTF-8"));
    Object results = createCall(outputVars).parseResponse(responseStream, binding);
    assertNull(results);
}

Example 3 with OutputVariable

use of org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable in project wikidata-query-rdf by wikimedia.

the class MWApiServiceCallUnitTest method testResults.

@Test
public void testResults() throws Exception {
    List<OutputVariable> outputVars = ImmutableList.of(new OutputVariable(makeVariable("var"), "@name"), new OutputVariable(makeVariable("header"), "/api/header/@value"), new OutputVariable(OutputVariable.Type.ITEM, makeVariable("item"), "@id"));
    when(template.getItemsPath()).thenReturn("/api/result");
    InputStream responseStream = new ByteArrayInputStream("<api><header value=\"heading\"></header><result name=\"result1\" id=\"Q1\"></result><result name=\"result2\"></result></api>".getBytes("UTF-8"));
    Iterator<IBindingSet> results = createCall(outputVars).parseResponse(responseStream, binding).getResultIterator();
    assertTrue(results.hasNext());
    IBindingSet result = results.next();
    assertThat(result, binds("var", "result1"));
    assertThat(result, binds("header", "heading"));
    assertThat(result, bindsItem("item", "Q1"));
    result = results.next();
    assertThat(result, binds("var", "result2"));
    assertThat(result, binds("header", "heading"));
    assertFalse(results.hasNext());
}

Example 4 with OutputVariable

use of org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable in project wikidata-query-rdf by wikimedia.

the class MWApiServiceCallUnitTest method testResultsMissingVar.

@Test
public void testResultsMissingVar() throws Exception {
    List<OutputVariable> outputVars = ImmutableList.of(new OutputVariable(makeVariable("var"), "@name"), new OutputVariable(makeVariable("data"), "text()"), new OutputVariable(makeVariable("header"), "/api/header/@value"));
    when(template.getItemsPath()).thenReturn("/api/result");
    InputStream responseStream = new ByteArrayInputStream("<api><header value=\"heading\"></header><result name=\"result1\">datadata</result><result>we need moar data</result></api>".getBytes("UTF-8"));
    Iterator<IBindingSet> results = createCall(outputVars).parseResponse(responseStream, binding).getResultIterator();
    assertTrue(results.hasNext());
    IBindingSet result = results.next();
    assertThat(result, binds("var", "result1"));
    assertThat(result, binds("data", "datadata"));
    assertThat(result, binds("header", "heading"));
    result = results.next();
    assertThat(result, notBinds("var"));
    assertThat(result, binds("data", "we need moar data"));
    assertThat(result, binds("header", "heading"));
    assertFalse(results.hasNext());
}

Example 5 with OutputVariable

use of org.wikidata.query.rdf.blazegraph.mwapi.ApiTemplate.OutputVariable in project wikidata-query-rdf by wikimedia.

the class ApiTemplateUnitTest method testServiceOutput.

@Test
public void testServiceOutput() throws Exception {
    JsonNode json = parseJson(JSON_CONFIG);
    ApiTemplate template = ApiTemplate.fromJSON(json);
    assertThat(template.getItemsPath(), equalTo("/api/query/pages/page/categories/cl"));
    JoinGroupNode patterns = new JoinGroupNode();
    // predefined variable
    patterns.addArg(new StatementPatternNode(new VarNode("somevar"), createURI(ApiTemplate.OutputVariable.Type.STRING.predicate()), createURI(paramNameToURI("category"))));
    // User-defined variable
    patterns.addArg(new StatementPatternNode(new VarNode("var2"), createURI(ApiTemplate.OutputVariable.Type.URI.predicate()), createConstant("@somedata")));
    // User-defined path variable
    patterns.addArg(new StatementPatternNode(new VarNode("var3"), createURI(ApiTemplate.OutputVariable.Type.ITEM.predicate()), createConstant("item/@wikibase_id")));
    // Variable with ordinal
    patterns.addArg(new StatementPatternNode(new VarNode("var4"), createURI(ApiTemplate.OutputVariable.Type.ORDINAL.predicate()), createConstant("goat")));
    ServiceNode serviceNode = new ServiceNode(createConstant("test"), patterns);
    List<OutputVariable> outputs = template.getOutputVars(serviceNode);
    assertThat(outputs.size(), equalTo(4));
    // Pre-defined variable
    OutputVariable var = outputs.get(0);
    assertThat(var.getName(), equalTo("somevar"));
    assertThat(var.getPath(), equalTo("@title"));
    assertFalse(var.isOrdinal());
    // User-defined variable
    var = outputs.get(1);
    assertThat(var.getName(), equalTo("var2"));
    assertThat(var.getPath(), equalTo("@somedata"));
    assertTrue(var.isURI());
    assertFalse(var.isOrdinal());
    assertThat(var.getURI("http://test.com/"), instanceOf(URI.class));
    // URI keeps the case
    assertThat(var.getURI("http://test.com/test").toString(), endsWith("test"));
    // User-defined variable which is an item
    var = outputs.get(2);
    assertThat(var.getName(), equalTo("var3"));
    assertThat(var.getPath(), equalTo("item/@wikibase_id"));
    assertTrue(var.isURI());
    assertFalse(var.isOrdinal());
    assertThat(var.getURI("test"), instanceOf(URI.class));
    // T172642: Item URIs will be uppercased
    assertThat(var.getURI("test").toString(), endsWith("TEST"));
    // Ordinal
    var = outputs.get(3);
    assertThat(var.getName(), equalTo("var4"));
    assertThat(var.getPath(), equalTo("."));
    assertFalse(var.isURI());
    assertTrue(var.isOrdinal());
}