For Dropwizard 0.8.x use 0.1.4 version from jCenter:
group: 'com.stansvec', name: 'dropwizard-authorization-el', version: '0.1.4'
This is JSR 341: Expression Language 3.0 Expression Engine for Authorization for Dropwizard extension allowing using expressions in @Auth#check() element.
Every expression is evaluated using context which is created for every request. This context may contain beans defined for current request as well as imports and variables defined globally. A class implementing ELContextProvider interface is responsible for providing such context. The easiest way is to use DefaultELContextProvider implementation. This implemantation already defines for every request following beans:
- user - containing principal instance
- principal - alias for user, i.e. containing same principal instance as user variable
- ctx - containing
ContainerRequestContextinstance
DefaultELContextProvider class has two optional constructor parameters ImportHandler importHandler and List<Variable> vars.
ImportHandlerclass can be used for defining custom imports.- List of
Variables can be used for defining custom variables.
DefaultELContextProvider can be subclassed and custom request bean variables can be defined by overriding defineRequestBeans method.
Note: There is NoJavaLangImportHandler class which doesn't import java.lang package in default. This is due to security reasons as otherwise methods like System.exit can be called.
public class TestContextProvider extends DefaultELContextProvider<TestUser> {
public TestContextProvider() {
super(createImportHandler(), createVariables());
}
private static ImportHandler createImportHandler() {
NoJavaLangImportHandler imports = new NoJavaLangImportHandler();
imports.importClass("com.stansvec.dropwizard.auth.exp.TestUser");
imports.importStatic("com.stansvec.dropwizard.auth.exp.AuthorizationMethods.hasName");
return imports;
}
private static List<Variable> createVariables() {
List<Variable> vars = new ArrayList<>();
vars.add(new Variable("username", "user.name"));
vars.add(new Variable("nameLength", "username.length()"));
vars.add(new Variable("path", "uriInfo.path"));
return vars;
}
@Override
protected void defineRequestBeans(Map<String, Object> beans, TestUser principal, ContainerRequestContext ctx) {
beans.put("roles", principal.getRoles());
beans.put("uriInfo", ctx.getUriInfo());
}
}
public class TestUser {
public static TestUser USER = new TestUser("user1", Collections.singleton("USER_ROLE"));
private final String name;
private final Set<String> roles;
public TestUser(String name, Set<String> roles) {
this.name = name;
this.roles = roles;
}
public String getName() {
return name;
}
public Set<String> getRoles() {
return roles;
}
}
public class AuthorizationMethods {
public static boolean hasName(TestUser user, String name) {
return name.equals(user.name);
}
}@Path("/protectedByExp")
public class ProtectedResource {
@GET
@Path("/admin-combined")
@Auth(roles = Admin.class, check = "user.name == 'admin1'")
public void combined() {}
@GET
@Path("/admin-exp-only")
@Auth(check = "hasName(user, 'admin1') && roles.stream().anyMatch(r -> (r == 'ADMIN_ROLE'))")
public void methodExecutionAndStreamUsage() {}
@GET
@Path("/int-var")
@Auth(check = "nameLength == 6")
public void variableUsage() {}
@GET
@Path("/static-field")
@Auth(check = "TestUser.USER.name == username")
public void staticFieldUsage() {}
@GET
@Path("/lambda")
@Auth(check = "(s -> s.toUpperCase().substring(0, s.length() - 1)) (username) == 'ADMIN'")
public void lambdaUsage() {}
@GET
@Path("/user/admin1")
@Auth(check = "path == 'protectedByExp/user/' += username")
public void pathVariable() {}
}new AuthConfiguration.Builder<TestUser>()
.setPolicy(..)
.supportExpressions(new ELEvaluation<>(new TestContextProvider()))
.addRole(..)
.setAuthentication(..)
.build();