JAX-RS Search

Advanced Search Queries

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Please see the specification text for some examples.

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Some of the following examples on this page may often refer to FIQL due to the fact FIQL has been supported for a long time, but the same examples will work with OData $filter expressions. For example, replace the "_s=name==CXF" query with "$filter=name eq CXF".

Please use a "search.query.parameter.name" contextual property to indicate to the runtime that a $filter query option need to be checked for the query expression and a "search.parser" property to point to the instance of org.apache.cxf.jaxrs.ext.search.odata.ODataParser, as shown in this test, see the startServers function.

When to use advanced queries.

Consider a typical query expression such as "a=avalue&c=cvalue". This can mean either "find all resources with 'a' and 'c' properties equal to 'avalue' and 'cvalue'" or "find all resources with 'a' or 'c' properties equal to 'avalue' and 'cvalue'". It is application specific on whether it is "and" or "or" as far as the combination of multiple query properties is concerned.

It is also to capture conditional expressions with the custom language, example, "find all resource with 'a' property less than 123" when a number of properties is large or the entities which can be searched are created dynamically.

Use FIQL or OData for capturing simple or medium complexity queries, typically in cases where a set of properties that a user can specify is well-known. Example, a book store resource will let users search books given a number of useful properties(those of Book and/or Library a given book is available in, etc).

Furthermore, consider using FIQL/OData and SearchConditionVisitor for the purpose of generalizing the search code, when the number of properties and entities is large, dynamic, etc.

Dependencies and Configuration

The following dependency is required starting from CXF 2.6.0And here is also an XML Spring configuration example (using SearchBean in this specific case):

 <cxf:bus><dependency>
  <cxf:properties>
    <entry key="search.query.parameter.name" value="$filter" /><groupId>org.apache.cxf</groupId>
    <entry key="search.parser"><artifactId>cxf-rt-rs-extension-search</artifactId>
      <bean class="org.apache.cxf.jaxrs.ext.search.odata.ODataParser">
         <constructor-arg value="#{ T(org.apache.cxf.jaxrs.ext.search.SearchBean) }" />
      </bean>
    </entry>
  </cxf:properties>
</cxf:bus>
 

Also note that Apache Olingo offers its own visitor model which can be used to work with JPA2, etc.

When to use advanced queries.

Consider a typical query expression such as "a=avalue&c=cvalue". This can mean either "find all resources with 'a' and 'c' properties equal to 'avalue' and 'cvalue'" or "find all resources with 'a' or 'c' properties equal to 'avalue' and 'cvalue'". It is application specific on whether it is "and" or "or" as far as the combination of multiple query properties is concerned.

It is also to capture conditional expressions with the custom language, example, "find all resource with 'a' property less than 123" when a number of properties is large or the entities which can be searched are created dynamically.

Use FIQL or OData for capturing simple or medium complexity queries, typically in cases where a set of properties that a user can specify is well-known. Example, a book store resource will let users search books given a number of useful properties(those of Book and/or Library a given book is available in, etc).

Furthermore, consider using FIQL/OData and SearchConditionVisitor for the purpose of generalizing the search code, when the number of properties and entities is large, dynamic, etc.

Dependencies and Configuration

The following dependency is required starting from CXF 2.6.0:

<version>2.6.0</version>
</dependency>

<!-- If working with OData -->
<!--
<dependency>
    <groupId>org.apache.olingo</groupId>
    <artifactId>olingo-odata2-core-incubating</artifactId>
    <version>1.1.0</version> 
</dependency>
-->

Additionally, starting from CXF 2.6.0, SearchContextProvider needs to be registered as jaxrs:provider.

Working with the queries

SearchContext needs be injected into an application code and used to retrieve a SearchCondition representing the current FIQL/OData query. This SearchCondition can be used in a number of ways for finding the matching data.

In this section we assume that the data to be matched are already available in memory. The follow-up section on converting the queries will show how the queries can be converted to some other query language typed or text expression.

So, suppose a list or map of Book instances is available. Here is one possible approach:

@Path("books")
public class Books {

    private Map<Long, Book> books;
    @Context
    private SearchContext context;

    @GET
    public List<Book> getBook() {

        SearchCondition<Book> sc = searchContext.getCondition(Book.class);
        // SearchCondition#isMet method can also be used to build a list of matching beans

        // iterate over all the values in the books map and return a collection of matching beans

   <dependency>
      <groupId>org.apache.cxf</groupId>
      <artifactId>cxf-rt-rs-extension-search</artifactId>
      <version>2.6.0</version>
   </dependency>

   <!-- If working with OData -->
   <!--
       <dependency>
            <groupId>org.apache.olingo</groupId>
            <artifactId>olingo-odata2-core-incubating</artifactId>
        List<Book> found =  <version>1.1.0</version> 
sc.findAll(books.values());
        return </dependency>found;
    -->
 

Additionally, starting from CXF 2.6.0, SearchContextProvider needs to be registered as jaxrs:provider.

Working with the queries

SearchContext needs be injected into an application code and used to retrieve a SearchCondition representing the current FIQL/OData query. This SearchCondition can be used in a number of ways for finding the matching data.

In this section we assume that the data to be matched are already available in memory. The follow-up section on converting the queries will show how the queries can be converted to some other query language typed or text expression.

So, suppose a list or map of Book instances is available. Here is one possible approach:

...

@Path("books")
public class Books {

private Map<Long, Book> books;
@Context
private SearchContext context;

 @GET
 public List<Book> getBook() {

   SearchCondition<Book> sc = searchContext.getCondition(Book.class);
   // SearchCondition#isMet method can also be used to build a list of matching beans

   // iterate over all the values in the books map and return a collection of matching beans
   List<Book> found = sc.findAll(books.values());
   return found;
 }
}

}
}

Note that a searchContext.getCondition(Book. class) call may return an arbitrary complex SearchCondition, it can be a simple primitiveexpression or a more complex, composite one.

Capturing the queries

For the query expression to be captured, a bean like Book.class is instantiated and has all the search properties injected into it. A complex composite expression will be 'injected' into a number of Book instances - something that may have to be optimized.

Note that by default, a bean such as Book class needs to have a matching property per every property name found in the FIQL expression, for example, given a 'name==b;id==123' expression, the Book class would need to have 'name' and 'id' properties available. The reason for this strict mode being enabled by default is that ignoring a property which can not be captured may lead to a false or unexpected match, for example, if Book 'name' property has been renamed to 'title' then ignoring the 'name' property will lead to a wider match. Thus, if the property does not exist, org.apache.cxf.jaxrs.ext.search.PropertyNotFoundException will be thrown; capturing it can let returning an empty response or retry with the more lax mode, see the next paragraph.

When a more lax parsing of FIQL expressions is expected, for example, where the primitive expressions are joined by "OR", using SearchBean (see one of the next subsections) or setting a contextual property "search.lax.property.match" will help. The former option is better when you need to know the list of all the properties which have been used in the expression, even those which will not be possible to use for the actual search; the latter option will simply have the unrecognized properties ignored.

Note that a "search.decode.values" property can be used to have the 'reserved' characters such as FIQL ',' or ';' characters passed as percent-encoded characters as part of the search property values.

Mapping of query properties to bean properties

As noted above, when a 'typed' bean such as Book.class is used to capture the expressions, a property found in the query expression that can not be mapped to a specific Book property will lead to an exception being reported or it can be optionally ignored. In the reality, there is a number of reasons why the direct match between properties found in query expressions and in capturing beans may not be ideal:

• Capturing beans may evolve independently of the actual queries; for example, a working query such as "name==b" will break if a Book 'name' gets renamed to 'title' which will make it difficult to have the queries bookmarked.
• Direct match will simply not work for cases where an actual bean property does not belong to the capturing bean itself but to one of its child properties; for example, a JPA2 Book entity may have an OwnerInfo bean with Name bean property which does contain a primitive 'name' property.

The preferred approach, when working with typed beans, is to register a bean properties map, using a "search.bean.property.map" contextual property or directly with SearchContext. For example, given

public class Book {

    private int id;
    private OwnerInfo ownerinfo;
    //setters and getters omitted for brevity
}

@Embeddable
public class OwnerInfo {

    private Address address;
    private Name name;
    //setters and getters omitted for brevity
}

@Embeddable
public class Name {

    private String name;
    //setters and getters omitted for brevity
}

and the following map:

<map>
 <!-- 'oname' is alias for the actual nested bean property -->
 <entry key="oname" value="ownerinfo.name.name"/>
</map>

will let users type and bookmark queries (and without seeing them producing unexpected results) like this one:

//Find all the books owned by Fred with id greater than 100
/books?_s=id=gt=100;oname=Fred

Note, a property name such as "ownerinfo.name.name" uses '.' to let the parser navigate to the actual Name bean which has a 'name' property. This can be optimized in cases where the owner bean is known to have either a constructor or static valueOf() method accepting the 'name' property, for example, given

public class Name

Note that a searchContext.getCondition(Book.class) call may return an arbitrary complex SearchCondition, it can be a simple primitive
expression or a more complex, composite one.

Capturing the queries

For the query expression to be captured, a bean like Book.class is instantiated and has all the search properties injected into it. A complex composite expression will be 'injected' into a number of Book instances - something that may have to be optimized.

Note that by default, a bean such as Book class needs to have a matching property per every property name found in the FIQL expression, for example, given a 'name==b;id==123' expression, the Book class would need to have 'name' and 'id' properties available. The reason for this strict mode being enabled by default is that ignoring a property which can not be captured may lead to a false or unexpected match, for example, if Book 'name' property has been renamed to 'title' then ignoring the 'name' property will lead to a wider match. Thus, if the property does not exist, org.apache.cxf.jaxrs.ext.search.PropertyNotFoundException will be thrown; capturing it can let returning an empty response or retry with the more lax mode, see the next paragraph.

When a more lax parsing of FIQL expressions is expected, for example, where the primitive expressions are joined by "OR", using SearchBean (see one of the next subsections) or setting a contextual property "search.lax.property.match" will help. The former option is better when you need to know the list of all the properties which have been used in the expression, even those which will not be possible to use for the actual search; the latter option will simply have the unrecognized properties ignored.

Note that a "search.decode.values" property can be used to have the 'reserved' characters such as FIQL ',' or ';' characters passed as percent-encoded characters as part of the search property values.

Mapping of query properties to bean properties

As noted above, when a 'typed' bean such as Book.class is used to capture the expressions, a property found in the query expression that can not be mapped to a specific Book property will lead to an exception being reported or it can be optionally ignored. In the reality, there is a number of reasons why the direct match between properties found in query expressions and in capturing beans may not be ideal:

• Capturing beans may evolve independently of the actual queries; for example, a working query such as "name==b" will break if a Book 'name' gets renamed to 'title' which will make it difficult to have the queries bookmarked.
• Direct match will simply not work for cases where an actual bean property does not belong to the capturing bean itself but to one of its child properties; for example, a JPA2 Book entity may have an OwnerInfo bean with Name bean property which does contain a primitive 'name' property.

The preferred approach, when working with typed beans, is to register a bean properties map, using a "search.bean.property.map" contextual property or directly with SearchContext. For example, given

public class Book {

    private int id;
    private OwnerInfo ownerinfo;
    //setters and getters omitted for brewity
}

@Embeddable
public class OwnerInfo {

    private AddressString addressname;
    privatepublic Name() name;{
    //setters} and
 getters omitted for brewity
}

@Embeddable
public class NameName(String name) {

        privatethis.name String= name;
    }
    //setters and getters omitted for brewitybrevity
}

the mapping between "oname" and "ownerinfo.name" will work too.

You can also have many to one mappings, for exampleand the following map:

<map>
 <!-- 'oname' is alias and 'owner' are aliases for the actual nested'ownerinfo.name.name' bean property -->
 <entry key="oname" value="ownerinfo.name.name"/>
</map>

will let users type and bookmark queries (and without seeing them producing unexpected results) like this one:

...

//Find all the books owned by Fred with id greater than 100
/books?_s=id=gt=100;oname=Fred

...

 <entry key="owner" value="ownerinfo.name.name"

...

public class Name {

    private String name;
    public Name() {
    } 
    public Name(String name) {
        this.name = name;
    }
    //setters and getters omitted for brewity
}

the mapping between "oname" and "ownerinfo.name" will work too.

You can also have many to one mappings, for example

...

/>
</map>

Dealing with mistyped property names

Consider a case where a documented search property is named as 'address' (lower case) and a query contains a mistyped 'Address' instead. In this case, unless a "search.lax.property.match" property is set, PropertyNotFoundException will be thrown.

Supporting case-insensitive property mapping is easy, register a "search.bean.property.map" (mentioned earlier) map as Java TreeMap

with a case-insensitive String.CASE_INSENSITIVE_ORDER Comparator.

However it will not help if the 'address' property was mistyped as 'adress'. In this case, "search.bean.property.map" might still be useful with having few more keys supporting some typical typos, example, 'adress' - 'address', 'addres' - 'address', etc.

Starting from  CXF 3.1.5, org.apache.cxf.jaxrs.ext.search.PropertyNameConverter  is available and might be used for a more sophisticated conversion of mistyped property names to correct names. 

The implementation can be registered as a "search.bean.property.converter" endpoint contextual property.

Parser properties

The parser properties are the ones which tell the parser how to treat the conversion of Date values and the unrecognized search property names.

...

// ?_s="level=gt=10"
SearchCondition<SearchBean> sc = searchContext.getCondition(SearchBean.class);

Map\<, String\> fieldMap = new HashMap\<String, String\>();
fieldMap.put("level", "LEVEL_COLUMN");

SQLPrinterVisitor<SearchBean> visitor = new SQLPrinterVisitor<SearchBean>(fieldMap, "table", "LEVEL_COLUMN");
sc.accept(visitor);
assertEquals("SELECT LEVEL_COLUMN FROM table 
              WHERE LEVEL_COLUMN > '10'",
              visitor.getResultgetQuery());

Converting the queries

SearchCondition can also be used to convert the search requirements (originally expressed in FIQL/OData) into other query languages.
A custom SearchConditionVisitor implementation can be used to convert SearchCondition objects into custom expressions or typed objects. CXF ships visitors for converting expressions to SQL, JPA 2.0 CriteriaQuery or TypedQuery, Lucene Query.

...

// ?_s="name==ami*;level=gt=10"
SearchCondition<Book> sc = searchContext.getCondition(Book.class);
SQLPrinterVisitor<Book> visitor = new SQLPrinterVisitor<Book>("table");
sc.accept(visitor);
assertEquals("SELECT * FROM table 
              WHERE 
              name LIKE 'ami%' 
              AND 
              level > '10'",
              visitor.getResultgetQuery());

Note that SQLPrinterVisitor can also be initialized with the names of columns and the field aliases map:

// ?_s="level=gt=10"
SearchCondition<Book> sc = searchContext.getCondition(Book.class);

Map<String, String> fieldMap = new HashMap<String, String>();
fieldMap.put("level", "LEVEL_COLUMN");

SQLPrinterVisitor<Book> visitor = new SQLPrinterVisitor<Book>(fieldMap, "table", "LEVEL_COLUMN");
sc.accept(visitor);
assertEquals("SELECT LEVEL_COLUMN FROM table 
              WHERE LEVEL_COLUMN > '10'",
              visitor.getResultgetQuery());

The fields map can help hide the names of the actual table columns/record fields from the Web frontend. Example, the users will know that the 'level' property is available while internally it will be converted to a LEVEL_COLUMN name.

Warning: Using the SQLPrinterVisitor may leave your service open to SQL injection attacks. Please take appropriate steps to avoid these attacks (for example validating queries using a custom PropertyValidator, or manually escaping the input values).

JPA 2.0

CXF 2.6.4 and CXF 2.7.1 introduce org.apache.cxf.jaxrs.ext.search.jpa.JPATypedQueryVisitor and org.apache.cxf.jaxrs.ext.search.jpa.JPACriteriaQueryVisitor which can be used to capture FIQL/OData expressions into
javax.persistence.TypedQuery or javax.persistence.criteria.CriteriaQuery objects.

...

public class Book {

    private String title;
    private Date date;
    private OwnerInfo ownerinfo;
    //setters and getters omitted for brewitybrevity
}

@Embeddable
public class OwnerInfo {

    private Address address;
    private Name name;
    //setters and getters omitted for brewitybrevity
}

@Embeddable
public class Name {

    private String name;
    //setters and getters omitted for brewitybrevity
}

@Embeddable
public class Address {

    private String street;
    //setters and getters omitted for brewitybrevity
}

the following code can be used:

...

public static class BookInfo {
        private int id;
     id;
    private String title;

        public BookInfo() {
            
        }
        
        public BookInfo(Integer id, String title) {
            this.id = id;
            this.title = title;
        }
        //setters and getters omitted for brewitybrevity
 }

// actual application code:

SearchCondition<Book> sc = searchContext.getCondition(Book.class);
JPACriteriaQueryVisitor<Book, BookInfo> visitor = 
    new JPACriteriaQueryVisitor<Book, BookInfo>(entityManager, Book.class, BookInfo.class);
sc.accept(visitor);

List<SingularAttribute<Book, ?>> selections = new LinkedList<SingularAttribute<Book, ?>>();
// Book_ class is generated by JPA2 compiler
selections.add(Book_.id);
selections.add(Book_.title);

visitor.selectConstruct(selections);

TypedQuery<BookInfo> query = visitor.getQuery();

List<BookInfo> bookInfo = typedQuery.getResultList();
return bookInfo;

JPA2 typed converters also support join operations in cases when explicit collections are used, for example, given:

@Entity(name = "Book")
public class Book {

    private List<BookReview> reviews = new LinkedList<BookReview>();
    private List<String> authors = new LinkedList<String>();
    // other properties omitted

    @OneToMany
    public List<BookReview> getReviews() {
        return reviews;
    }

    public void setReviews(List<BookReview> reviews) {
        this.reviews = reviews;
    }

    @ElementCollection
    public List<String> getAuthors() {
        return authors;
    }

    public void setAuthors(List<String> authors) {
        this.authors = authors;
    }
}

@Entity
public class BookReview {
    private Review review;
    private List<String> authors = new LinkedList<String>();
    private Book book;
    // other properties omitted    

    public Review getReview() {
        return review;
    }

    public void setReview(Review review) {
        this.review = review;
    }

    @OneToOne
    public Book getBook() {
        return book;
    }

    public void setBook(Book book) {
        this.book = book;
    }

    @ElementCollection
    public List<String> getAuthors() {
        return authors;
    }

    public void setAuthors(List<String> authors) {
        this.authors = authors;
    }

    public static enum Review {
        GOOD,
        BAD
    }
}

the following will find "all the books with good reviews written by Ted":

SearchCondition<Book> filter = new FiqlParser<Book>(Book.class).parse("reviews.review==good;reviews.authors==Ted");
// in practice, map "reviews.review" to "review", "reviews.authors" to "reviewAuthor" 
// and have a simple query like "review==good;reviewAuthor==Ted" instead

SearchConditionVisitor<Book, TypedQuery<Book>> jpa = new JPATypedQueryVisitor<Book>(em, Book.class);
filter.accept(jpa);
TypedQuery<Book> query = jpa.getQuery();
return query.getResultList();

org.apache.cxf.jaxrs.ext.search.jpa.JPALanguageVisitor for converting FIQL/OData expressions into JPQL expressions have also been introduced.

...

SearchCondition<Book> filter = new FiqlParser<Book>(Book.class).parse("reviews.review==good;reviews.authors==Ted");

JPACriteriaQueryVisitor<Book, Long> jpa = new JPACriteriaQueryVisitor<Book, Long>(em, Book.class, Long.class);
filter.accept(jpa);
long count = jpa.count();

...

Second, only when using FIQL, a count extension can be used. For example, one may want to find 'all the books written by at least two authors or all the books with no reviews'.
If a collection entity such as BookReview has a non primitive type, then typing "reviews==0" is all what is needed, otherwise a count extension needs to be used, for example: "count(authors)=ge=2"

...

Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_4_9);

// Lower-case filter and stop-words filter are part of the StandardAnalyzer
SearchCondition<SearchBean> filter = new FiqlParser<SearchBean>(SearchBean.class).parse("contents==pears and APPLES");
LuceneQueryVisitor<SearchBean> lucene = new LuceneQueryVisitor<SearchBean>("contents", analyzer);
lucene.visit(filter);

org.apache.lucene.search.Query query = lucene.getQuery();

...

LDAP

Mapping of FIQL/OData expressions to LDAP queries as defined by RFC-4515 is supported starting from CXF 2.7.1 with the help of org.apache.cxf.jaxrs.ext.search.ldap.LdapQueryVisitor. Use this visitor when working with LDAP or OSGI.

...

// FIQL "oclass=Bar"

// map 'oclass' used in the FIQL query to the actual property name, 'objectClass'
LdapQueryVisitor<Condition> visitor = 
   new LdapQueryVisitor<Condition>(Collections.singletonMap("oclass", "objectClass"));

filter.accept(visitor.visitor());
String ldap = visitor.getQuery();

Note that since CXF 3.2.5 the query values are encoded by default, to prevent possible LDAP injection attacks. If you want to support wildcard searching with the LdapQueryVisitor from CXF 3.2.5 onwards, it is necessary to set the 'encodeQueryValues' property of LdapQueryVisitor to 'false'.

Custom visitors

In cases when a custom conversion has to be done, a converter for doing the untyped (example, SQL) or typed (example, JPA2 TypedQuery) conversions can be provided.

...

public class CustomSQLVisitor<T> extends AbstractSearchConditionVisitor<T, String> {

    private String tableName;
    private StringBuilder sb = new StringBuilder();

    public void visit(SearchCondition<T> sc) {
        
        if (sb == null) {
            sb = new StringBuilder();
            // start the expression as needed, example
            // sb.append("Select from ").append(tableName);
        }
        
        PrimitiveStatement statement = sc.getStatement();
        if (statement != null) {
                // ex "a > b"
                // use statement.getValue()
                // use statement.getConditionType() such as greaterThan, lessThan
                // use statement.getProperty();
                // to convert "a > b" into SQL expression
                sb.append(toSQL(statement));         
        } else {
            // composite expression, ex "a > b;c < d"
            for (SearchCondition<T> condition : sc.getSearchConditions()) {
                // pre-process, example sb.append("(");
                condition.accept(this);
                // post-process, example sb.append(")");
            }
        }
    }

    public String getQuery() {
        return sb.toString();
    }
}

...

public class CustomTypedVisitor<T> extends AbstractSearchConditionVisitor<T, Query> {

    private Stack<List<Query>> queryStack = new Stack<List<Query>>();


    public void visit(SearchCondition<T> sc) {
                
        PrimitiveStatement statement = sc.getStatement();
        if (statement != null) {
                // ex "a > b"
                // use statement.getValue()
                // use statement.getConditionType() such as greaterThan, lessThan
                // use statement.getProperty();
                // to convert "a > b" into Query object
                Query query = buildSimpleQuery(statement);
                queryStack.peek().add(query);                 

        } else {
            // composite expression, ex "a > b;c < d"
            queryStack.push(new ArrayList<Query>());

            for (SearchCondition<T> condition : sc.getSearchConditions()) {
                condition.accept(this);
            }

            boolean orCondition = sc.getConditionType() == ConditionType.OR;
            List<Query> queries = queryStack.pop();
            queryStack.peek().add(createCompositeQuery(queries, orCondition));
        }
    }

    public Query getResultgetQuery() {
        return queryStack.peek().get(0);
    }
}

...

@Path("/search")
public class SearchEngine {
    @Context
    private UriInfo ui;

    @GET
    public List<Book> findBooks() {
        MultivaluedMap<String, String> params = ui.getQueryParameters();
        String query = params.getFirst("_s"); // or $filter, etc
        // delegate to your own custom handler 

        // note that the original search expression can also be retrieved 
        // using a SearchContext.getSearchExpression() method
}

Converting the queries with QueryContext

QueryContext is the helper context available from CXF 2.7.1 which makes it simpler for the application code to
get the converted query expression, with the actual converter/visitor registered as the jaxrs contextual property, for example:

import java.util.ArrayList;
import java.util.List;
import org.apache.cxf.jaxrs.JAXRSServerFactoryBean;
import org.apache.cxf.jaxrs.ext.search.QueryContextProvider;
import org.apache.cxf.jaxrs.ext.search.SearchBean;
import org.apache.cxf.jaxrs.ext.search.visitor.SBThrealLocalVisitorState;
import org.apache.cxf.jaxrs.ext.search.sql.SQLPrinterVisitor;

import books.BookStore;

// Register the visitor:
JAXRSServerFactoryBean sf = new JAXRSServerFactoryBean();
List<Object> providers = new ArrayList<Object>();
providers.add(new QueryContextProvider());
sf.setProviders(providers);

SQLPrinterVisitor<SearchBean> sqlVisitor = new SQLPrinterVisitor<SearchBean>("books");
sqlVisitor.setVisitorState(new SBThrealLocalVisitorState());
sf.getProperties(true).put("search.visitor", sqlVisitor);


sf.setResourceClasses(BookStore.class);
server = sf.create();

...

@Path("/")
public class BookStore { 
    @GET
    @Path("/books/{expression}")
    @Produces("application/xml")
    public List<Book> getBookQueryContext(@PathParam("expression") String expression, 
                                      @Context QueryContext searchContext) 
        throws BookNotFoundFault {
        String sqlExpression = searchContext.getConvertedExpression(expression, Book.class);
        // pass it to the SQL DB and return the list of Books
    }
}

...

// GET /search?a=a1&a=v2
String exp = searchContext.getSearchExpression();
assertEquals("(a==a1,a==a2)", exp);

// GET /search?a=a1&b=b1
exp = searchContext.getSearchExpression();
assertEquals("(a==a1;b==b1)", exp);

Also, by default, if a query property name ends with "From" then "=ge=" (greater or equals to) will be used, and if ends with "Till" then "=lt=" will be used, for example:

...

First option is to have a bean capturing specific property values do a domain specific validation. For example, a Book.class may have its setName(String name) method validating the name value.
Another option is to inject a custom validator into a visitor which is used to build the untyped or typed query.

Finally, avoid letting users to use properties whose values which can not be well validated in the application code. Using a typed capturing bean like Book.class offers a perfect option to limit a number of supported properties to the ones known to be related to Books.

Bean Validation 1.1 can also be used.

Building the queries

FIQL

CXF 2.4.0 introduces SearchConditionBuilder which makes it simpler to build FIQL queries. SearchConditionBuilder is an abstract class that returns a FIQL builder by default:

be well validated in the application code. Using a typed capturing bean like Book.class offers a perfect option to limit a number of supported properties to the ones known to be related to Books.

Bean Validation 1.1 can also be used.

Building the queries

FIQL

CXF 2.4.0 introduces SearchConditionBuilder which makes it simpler to build FIQL queries. SearchConditionBuilder is an abstract class that returns a FIQL builder by default:

SearchConditionBuilder b = SearchConditionBuilder.instance();
String fiqlQuery = b.is("id").greaterThan(123).query();

WebClient wc = WebClient.create("http://books.com/search");
wc.query("_s", fiqlQuery);
// find all the books with id greater than 123 
Collection books = wc.getCollection(Book.class);

Here is an example of building more complex queries:

// OR condition
String ret = b.is("foo").greaterThan(20).or().is("foo").lessThan(10).query();
assertEquals("foo=gt=20,foo=lt=10", ret);

// AND condition
String ret = b.is("foo").greaterThan(20).and().is("bar").equalTo("plonk").query();
assertEquals("foo=gt=20;bar==plonk", ret);

// Complex condition
String ret

SearchConditionBuilder b = SearchConditionBuilder.instance();
String fiqlQuery = b.is("idfoo").greaterThanequalTo(123.4).queryor();

WebClient wc = WebClient.create("http://books.com/search");
wc.query("_s", fiqlQuery);
// find all the books with id greater than 123 
Collection books = wc.getCollection(Book.class);
.and(
            b.is("bar").equalTo("asadf*"), 
            b.is("baz").lessThan(20)).query();
assertEquals("foo==123.4,(bar==asadf*;baz=lt=20.0)", ret);

Note, starting from CXF 2.7.1 the following can be used to make connecting multiple primitive expressions simplerHere is an example of building more complex queries:

// ORAND condition
String ret = b.is("foo").greaterThan(20).or, '.and("bar")' is a shortcut for "and().is("foo").lessThan(10).query();
assertEquals("foo=gt=20,foo=lt=10", ret);

// AND conditionbar")", similar shortcut is supported for 'or'
String ret = b.is("foo").greaterThan(20).and().is("bar").equalTo("plonk").query();
assertEquals("foo=gt=20;bar==plonk", ret);

More updates to the builder API are available on the trunk:

// ComplexOR condition
String ret = b.is("foo").equalTo(123.420).or().and(
            b.is("barfoo").equalTo("asadf*"), 
            (10).query();
assertEquals("foo==20,foo==10", ret);

// Same query, shorter expression
String ret = b.is("bazfoo").lessThanequalTo(20, 10)).query();
assertEquals("foo==123.4,(bar==asadf*;baz=lt=20.0)20,foo==10", ret);

Note, starting from CXF 2.7.1 the following can be used to make connecting multiple primitive expressions simpler:and

// AND condition, '.and("bar")' is a shortcut for "and().is("bar")", similar shortcut is supported for 'or' Connecting composite or() and and() expressions will add "()" implicitly:
String ret = b.is("foo").equalTo(20, 10).and("bar").lessThan(10).query();
assertEquals("(foo==20,foo==10);bar=lt=10", ret);

// wrap() method can be used to wrap explicitly:

String ret = b.is("foo").greaterThanequalTo(2010).and("bar").lessThan(10).wrap().equalToor("plonkbar").greaterThan(25).query();
assertEquals("(foo=gt=20;bar=lt=10),bar=gt=plonk25", ret);

Using dates in queries

By default, the date values have to have the following format: "yyyy-MM-dd", for exampleMore updates to the builder API are available on the trunk:

// OR condition
String ret = b.is("foo").equalTo(20).or().is("foo").equalTo(10).query();
assertEquals("foo==20,foo==10", ret);

// Same query, shorter expression
String ret = b.is("foo").equalTo(20, 10).query();
assertEquals("foo==20,foo==10", ret);

?_search=date=le=2010-03-11

A custom date format can be supported. Use "search.date-format" contextual property, example, "search.date-format"="yyyy-MM-dd'T'HH:mm:ss" will let users type:

?_search=time=le=2010-03-11T18:00:00

If needed, "search.timezone.support" can be enabled to get the timezones supported too.

At the moment, for custom date formats be recognized by SearchConditionBuilder, FIQLSearchConditionBuilder has to be created explicitly:and

//Map<String, ConnectingString> composite or() and and() expressions will add "()" implicitly:
String ret = b.is("foo").equalTo(20, 10).and("bar").lessThan(10).query();
assertEquals("(foo==20,foo==10);bar=lt=10", ret);

// wrap() method can be used to wrap explicitly:
props = new HashMap<String, String>();
props.put("search.date-format", "yyyy-MM-dd'T'HH:mm:ss");
props.put("search.timezone.support", "false");

Date d = df.parse("2011-03-01 12:34:00");
        
FiqlSearchConditionBuilder bCustom = new FiqlSearchConditionBuilder(props);
        
String ret = bbCustom.is("foo").equalTo(10).and("bar").lessThan(10).wrap().or("bar").greaterThan(25).d).query();
assertEquals("(foo==20;bar=lt=10),bar=gt=252011-03-01T12:34:00", ret);

OData

Please work with Apache Olingo to produce OData queries from the code.

Using dates in queries

...

?_search=date=

...

ge=

...

-

...

P90D

A custom date format can be supported. Use "search.date-format" contextual property, example, "search.date-format"="yyyy-MM-dd'T'HH:mm:ss" will let users type:

...

?_search=time=le=2010-03-11T18:00:00

Alternative query languages

Custom org.apache.cxf.jaxrs.ext.search.SearchConditionParser implementations can be registered as a "search.parser" contextual property starting from CXF 3.0.0-milestone2.

OData

Please use a "search.query.parameter.name" contextual property to indicate to the runtime that an OData '$filter' query option needs to be checked for the query expression and a "search.parser" property to point to the instance of org.apache.cxf.jaxrs.ext.search.odata.ODataParser, as shown in this test, see the startServers function.

And here is also an XML Spring configuration example (using SearchBean in this specific case):

 <cxf:bus>
  <cxf:properties>
    <entry key="search.query.parameter.name" value="$filter" />
    <entry key="search.parser">
      <bean class="org.apache.cxf.jaxrs.ext.search.odata.ODataParser">

If needed, "search.timezone.support" can be enabled to get the timezones supported too.

At the moment, for custom date formats be recognized by SearchConditionBuilder, FIQLSearchConditionBuilder has to be created explicitly:

Map<String, String> props = new HashMap<String, String>();
props.put("search.date-format", "yyyy-MM-dd'T'HH:mm:ss");
props.put("search.timezone.support", "false");

Date d = df.parse("2011-03-01 12:34:00");
        
FiqlSearchConditionBuilder bCustom<constructor-arg value= new FiqlSearchConditionBuilder(props);
    "#{ T(org.apache.cxf.jaxrs.ext.search.SearchBean) }" />
      </bean>
    </entry>
String ret = bCustom.is("foo").equalTo(d).query();
assertEquals("foo==2011-03-01T12:34:00", ret);

Alternative query languages

 </cxf:properties>
</cxf:bus>
 

Also note that Apache Olingo offers its own visitor model which can be used to work with JPA2, etc.Custom org.apache.cxf.jaxrs.ext.search.SearchConditionParser implementations can be registered as a "search.parser" contextual property starting from CXF 3.0.0-milestone2.

Content Extraction

Starting from CXF 3.0.2, the content extraction support has been added in order to complement the search capabilites with text extraction from various document formats (PDF, ODF, DOC,TXT,RTFin order to complement the search capabilites with text extraction from various document formats (PDF, ODF, DOC,TXT,RTF,...). It is based on Apache Tika and is available in two shapes: raw content extraction (TikaContentExtractor) and Lucene document content extraction (TikaLuceneContentExtractor).

Using TikaContentExtractor

The purpose of Tika content extractor is to provide the essential support of text extraction from supported document formats. Additionally, the metadata is being extracted as well depending on the document format (author, modified, created, pages, ...). It is based on Apache Tika and is available in two shapes: raw content extraction (TikaContentExtractor) and Lucene document content extraction (TikaLuceneContentExtractor).

Using TikaContentExtractor

The TikaContentExtractor accepts the list of supported parsers and returns the extracted metadata together with the desired extracted content format (by default raw text). For example:

TikaContentExtractor extractor = new TikaContentExtractor(new PDFParser(), true);
TikaContent content = extractor .extract( Files.newInputStream( new File( "testPDF.pdf" ).toPath() ) );

By default, the TikaContentExtractor  also performs the content type detection and validation, which could be turned off using the 'validateMediaType' constructor argument.

Using TikaLuceneContentExtractor

The TikaLuceneContentExtractor is very similar to TikaContentExtractor but instead of raw content and metadata it returns prepared Lucene document. However, in order to properly create the Lucene document which is ready to be indexed, TikaLuceneContentExtractor  accepts an additional parameter, LuceneDocumentMetadata, with the field types and type convertersThe purpose of Tika content extractor is to provide the essential support of text extraction from supported document formats. Additionally, the metadata is being extracted as well depending on the document format (author, modified, created, pages, ...). The TikaContentExtractor accepts the list of supported parsers and returns the extracted metadata together with the desired extracted content format. For example:

TikaContentExtractorLuceneDocumentMetadata documentMetadata = new LuceneDocumentMetadata("contents").withField("modified", Date.class);
TikaLuceneContentExtractor extractor = new TikaContentExtractorTikaLuceneContentExtractor(new PDFParser(), true);
TikaContentDocument contentdocument = extractor .extract( Files.newInputStream( new File( "testPDF.pdf" ).toPath() ) );( new File( "testPDF.pdf" ).toPath() ), documentMetadata  );

At this point, the document is ready to be analyzed and indexed. The TikaLuceneContentExtractor uses LuceneDocumentMetadata to create the properly typed document fields and currently supports DoubleField, FloatField, LongField, IntField, IntField, TextField (for content) and StringField (also used to store dates).

To demonstrate the full power of the CXF 3.0.2 content extraction and search capabiities, the demo project 'jax_rs_search' has been developed and is distributed in the samples bundle. The project could be found in the official Apache CXF Github repository. It integrates together Apache CXF, Apache Lucene and Apache Tika showing off some advanced features related to custom analyzers and different filter criteria (keyword and  phrase search)By default, the TikaContentExtractor  also performs the content type detection and validation, which could be turned off using the 'validateMediaType' constructor argument.