Examples with PredicateExtractionVisitor com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor used on opensource projects

Example 6 with PredicateExtractionVisitor

use of com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor in project elide by yahoo.

the class RootCollectionFetchQueryBuilder method build.

/**
 * Constructs a query that fetches a root collection.
 *
 * @return the constructed query
 */
@Override
public Query build() {
    Type<?> entityClass = this.entityProjection.getType();
    String entityName = entityClass.getCanonicalName();
    String entityAlias = getTypeAlias(entityClass);
    Query query;
    FilterExpression filterExpression = entityProjection.getFilterExpression();
    if (filterExpression != null) {
        PredicateExtractionVisitor extractor = new PredicateExtractionVisitor();
        Collection<FilterPredicate> predicates = filterExpression.accept(extractor);
        // Build the WHERE clause
        String filterClause = WHERE + new FilterTranslator(dictionary).apply(filterExpression, USE_ALIAS);
        // Build the JOIN clause
        String joinClause = getJoinClauseFromFilters(filterExpression) + getJoinClauseFromSort(entityProjection.getSorting()) + extractToOneMergeJoins(entityClass, entityAlias);
        boolean requiresDistinct = entityProjection.getPagination() != null && containsOneToMany(filterExpression);
        boolean sortOverRelationship = entityProjection.getSorting() != null && entityProjection.getSorting().getSortingPaths().keySet().stream().anyMatch(path -> path.getPathElements().size() > 1);
        if (requiresDistinct && sortOverRelationship) {
            // SQL does not support distinct and order by on columns which are not selected
            throw new InvalidValueException("Combination of pagination, sorting over relationship and" + " filtering over toMany relationships unsupported");
        }
        query = session.createQuery(SELECT + (requiresDistinct ? DISTINCT : "") + entityAlias + FROM + entityName + AS + entityAlias + SPACE + joinClause + SPACE + filterClause + SPACE + getSortClause(entityProjection.getSorting()));
        // Fill in the query parameters
        supplyFilterQueryParameters(query, predicates);
    } else {
        query = session.createQuery(SELECT + entityAlias + FROM + entityName + AS + entityAlias + SPACE + getJoinClauseFromSort(entityProjection.getSorting()) + extractToOneMergeJoins(entityClass, entityAlias) + SPACE + getSortClause(entityProjection.getSorting()));
    }
    addPaginationToQuery(query);
    return query;
}

Example 7 with PredicateExtractionVisitor

use of com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor in project elide by yahoo.

the class FilterPredicateTest method parse.

private Map<String, Set<FilterPredicate>> parse(MultivaluedMap<String, String> queryParams) {
    PredicateExtractionVisitor visitor = new PredicateExtractionVisitor();
    Map<String, FilterExpression> expressionMap;
    try {
        expressionMap = strategy.parseTypedExpression("/book", queryParams, NO_VERSION);
    } catch (ParseException e) {
        throw new BadRequestException(e.getMessage());
    }
    Map<String, Set<FilterPredicate>> returnMap = new HashMap<>();
    for (Map.Entry<String, FilterExpression> entry : expressionMap.entrySet()) {
        String typeName = entry.getKey();
        FilterExpression expression = entry.getValue();
        if (!returnMap.containsKey(typeName)) {
            returnMap.put(typeName, new HashSet<>());
        }
        returnMap.get(typeName).addAll(expression.accept(visitor));
    }
    return returnMap;
}

Example 8 with PredicateExtractionVisitor

use of com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor in project elide by yahoo.

the class SQLQueryEngine method supplyFilterQueryParameters.

/**
 * Given a Prepared Statement, replaces any parameters with their values from client query.
 *
 * @param query The client query
 * @param stmt Customized Prepared Statement
 * @param dialect the SQL dialect
 */
private void supplyFilterQueryParameters(Query query, NamedParamPreparedStatement stmt, SQLDialect dialect) {
    Collection<FilterPredicate> predicates = new ArrayList<>();
    if (query.getWhereFilter() != null) {
        predicates.addAll(query.getWhereFilter().accept(new PredicateExtractionVisitor()));
    }
    if (query.getHavingFilter() != null) {
        predicates.addAll(query.getHavingFilter().accept(new PredicateExtractionVisitor()));
    }
    for (FilterPredicate filterPredicate : predicates) {
        Column column = metaDataStore.getColumn(filterPredicate.getEntityType(), filterPredicate.getField());
        if (filterPredicate.getOperator().isParameterized()) {
            boolean shouldEscape = filterPredicate.isMatchingOperator();
            filterPredicate.getParameters().forEach(param -> {
                try {
                    Object value = param.getValue();
                    value = convertForJdbc(filterPredicate.getEntityType(), column, value, dialect);
                    stmt.setObject(param.getName(), shouldEscape ? param.escapeMatching() : value);
                } catch (SQLException e) {
                    throw new IllegalStateException(e);
                }
            });
        }
    }
}

Example 9 with PredicateExtractionVisitor

use of com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor in project elide by yahoo.

the class EntityProjectionTranslator method addHavingMetrics.

/**
 * Adds to the list of queried metrics any metric in the HAVING filter that has not been explicitly requested
 * by the client.
 */
private void addHavingMetrics() {
    if (havingFilter == null) {
        return;
    }
    // Flatten the HAVING filter expression into a list of predicates...
    havingFilter.accept(new PredicateExtractionVisitor()).forEach(filterPredicate -> {
        String fieldName = filterPredicate.getField();
        // If the predicate field is a metric
        if (queriedTable.getMetric(fieldName) != null) {
            // If the query doesn't contain this metric.
            if (metrics.stream().noneMatch((metric -> metric.getName().equals(fieldName)))) {
                // Construct a new projection and add it to the query.
                MetricProjection havingMetric = engine.constructMetricProjection(queriedTable.getMetric(fieldName), fieldName, new HashMap<>());
                metrics.add(havingMetric);
            }
        }
    });
}

Example 10 with PredicateExtractionVisitor

use of com.yahoo.elide.core.filter.expression.PredicateExtractionVisitor in project elide by yahoo.

the class AbstractHQLQueryBuilder method getJoinClauseFromFilters.

/**
 * Extracts all the HQL JOIN clauses from given filter expression.
 * @param filterExpression the filter expression to extract a join clause from
 * @param skipFetches JOIN but don't FETCH JOIN a relationship.
 * @return an HQL join clause
 */
protected String getJoinClauseFromFilters(FilterExpression filterExpression, boolean skipFetches) {
    PredicateExtractionVisitor visitor = new PredicateExtractionVisitor(new ArrayList<>());
    Collection<FilterPredicate> predicates = filterExpression.accept(visitor);
    return predicates.stream().map(predicate -> extractJoinClause(predicate.getPath(), skipFetches)).collect(Collectors.joining(SPACE));
}