When working with gRPC, we need to generate the gRPC client and server interfaces from our .proto service definition via protocol buffer compiler (protoc) or using Gradle or Maven protoc build plugin.
Flow now: protobuf file -> java code -> gRPC client.
So, is there any way to skip this step?
How to create a generic gRPC client that can call the server directly from the protobuf file without compile into java code?
Or, is there a way to Generated Code at runtime?
Flow expect: protobuf file -> gRPC client.
I want to build a generic gRPC client system with the input are protobuf files along with description of method, package, message request ... without having to compile again for each protobuf.
Thank you very much.
Protobuf systems really need protoc to be run. However, the generated code could be skipped. Instead of passing something like --java_out and --grpc_java_out to protoc you can pass --descriptor_set_out=FILE which will parse the .proto file into a descriptor file. A descriptor file is a proto-encoded FileDescriptorSet. This is the same basic format as used with the reflection service.
Once you have a descriptor, you can load it a FileDescriptor at a time and create a DynamicMessage.
Then for the gRPC piece, you need to create a gRPC MethodDescriptor.
static MethodDescriptor from(
Descriptors.MethodDescriptor methodDesc
) {
return MethodDescriptor.<DynamicMessage, DynamicMessage>newBuilder()
// UNKNOWN is fine, but the "correct" value can be computed from
// methodDesc.toProto().getClientStreaming()/getServerStreaming()
.setType(getMethodTypeFromDesc(methodDesc))
.setFullMethodName(MethodDescriptor.generateFullMethodName(
serviceDesc.getFullName(), methodDesc.getName()))
.setRequestMarshaller(ProtoUtils.marshaller(
DynamicMessage.getDefaultInstance(methodDesc.getInputType())))
.setResponseMarshaller(ProtoUtils.marshaller(
DynamicMessage.getDefaultInstance(methodDesc.getOutputType())))
.build();
static MethodDescriptor.MethodType getMethodTypeFromDesc(
Descriptors.MethodDescriptor methodDesc
) {
if (!methodDesc.isServerStreaming()
&& !methodDesc.isClientStreaming()) {
return MethodDescriptor.MethodType.UNARY;
} else if (methodDesc.isServerStreaming()
&& !methodDesc.isClientStreaming()) {
return MethodDescriptor.MethodType.SERVER_STREAMING;
} else if (!methodDesc.isServerStreaming()) {
return MethodDescriptor.MethodType.CLIENT_STREAMING);
} else {
return MethodDescriptor.MethodType.BIDI_STREAMING);
}
}
At that point you have everything you need and can call Channel.newCall(method, CallOptions.DEFAULT) in gRPC. You're also free to use ClientCalls to use something more similar to the stub APIs.
So dynamic calls are definitely possible, and is used for things like grpcurl. But it also is not easy and so is generally only done when necessary.
I did it in Java, and the step is:
Call reflection service to get FileDescriptorProto list by method name
Get FileDescriptor of method from FileDescriptorProto list by package name, service name
Get MethodDescriptor from ServiceDescriptor which get from the FileDescriptor
Generate a MethodDescriptor<DynamicMessage, DynamicMessage> by MethodDescriptor
Build request DynamicMessage from content like JSON or others
Call method
Parse response content to JSON from DynamicMessage response
You can reference the full sample in project helloworlde/grpc-java-sample#reflection
And proto is:
syntax = "proto3";
package io.github.helloworlde.grpc;
option go_package = "api;grpc_gateway";
option java_package = "io.github.helloworlde.grpc";
option java_multiple_files = true;
option java_outer_classname = "HelloWorldGrpc";
service HelloService{
rpc SayHello(HelloMessage) returns (HelloResponse){
}
}
message HelloMessage {
string message = 2;
}
message HelloResponse {
string message = 1;
}
Start server for this proto by yourself, and the full code in Java just like:
import com.google.protobuf.ByteString;
import com.google.protobuf.DescriptorProtos;
import com.google.protobuf.Descriptors;
import com.google.protobuf.DynamicMessage;
import com.google.protobuf.InvalidProtocolBufferException;
import com.google.protobuf.TypeRegistry;
import com.google.protobuf.util.JsonFormat;
import io.grpc.CallOptions;
import io.grpc.ManagedChannel;
import io.grpc.ManagedChannelBuilder;
import io.grpc.MethodDescriptor;
import io.grpc.protobuf.ProtoUtils;
import io.grpc.reflection.v1alpha.ServerReflectionGrpc;
import io.grpc.reflection.v1alpha.ServerReflectionRequest;
import io.grpc.reflection.v1alpha.ServerReflectionResponse;
import io.grpc.stub.ClientCalls;
import io.grpc.stub.StreamObserver;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.TimeUnit;
import java.util.stream.Collectors;
#Slf4j
public class ReflectionCall {
public static void main(String[] args) throws InterruptedException {
// 反射方法的格式只支持 package.service.method 或者 package.service
String methodSymbol = "io.github.helloworlde.grpc.HelloService.SayHello";
String requestContent = "{\"message\": \"Reflection\"}";
// 构建 Channel
ManagedChannel channel = ManagedChannelBuilder.forAddress("127.0.0.1", 9090)
.usePlaintext()
.build();
// 使用 Channel 构建 BlockingStub
ServerReflectionGrpc.ServerReflectionStub reflectionStub = ServerReflectionGrpc.newStub(channel);
// 响应观察器
StreamObserver<ServerReflectionResponse> streamObserver = new StreamObserver<ServerReflectionResponse>() {
#Override
public void onNext(ServerReflectionResponse response) {
try {
// 只需要关注文件描述类型的响应
if (response.getMessageResponseCase() == ServerReflectionResponse.MessageResponseCase.FILE_DESCRIPTOR_RESPONSE) {
List<ByteString> fileDescriptorProtoList = response.getFileDescriptorResponse().getFileDescriptorProtoList();
handleResponse(fileDescriptorProtoList, channel, methodSymbol, requestContent);
} else {
log.warn("未知响应类型: " + response.getMessageResponseCase());
}
} catch (Exception e) {
log.error("处理响应失败: {}", e.getMessage(), e);
}
}
#Override
public void onError(Throwable t) {
}
#Override
public void onCompleted() {
log.info("Complete");
}
};
// 请求观察器
StreamObserver<ServerReflectionRequest> requestStreamObserver = reflectionStub.serverReflectionInfo(streamObserver);
// 构建并发送获取方法文件描述请求
ServerReflectionRequest getFileContainingSymbolRequest = ServerReflectionRequest.newBuilder()
.setFileContainingSymbol(methodSymbol)
.build();
requestStreamObserver.onNext(getFileContainingSymbolRequest);
channel.awaitTermination(10, TimeUnit.SECONDS);
}
/**
* 处理响应
*/
private static void handleResponse(List<ByteString> fileDescriptorProtoList,
ManagedChannel channel,
String methodFullName,
String requestContent) {
try {
// 解析方法和服务名称
String fullServiceName = extraPrefix(methodFullName);
String methodName = extraSuffix(methodFullName);
String packageName = extraPrefix(fullServiceName);
String serviceName = extraSuffix(fullServiceName);
// 根据响应解析 FileDescriptor
Descriptors.FileDescriptor fileDescriptor = getFileDescriptor(fileDescriptorProtoList, packageName, serviceName);
// 查找服务描述
Descriptors.ServiceDescriptor serviceDescriptor = fileDescriptor.getFile().findServiceByName(serviceName);
// 查找方法描述
Descriptors.MethodDescriptor methodDescriptor = serviceDescriptor.findMethodByName(methodName);
// 发起请求
executeCall(channel, fileDescriptor, methodDescriptor, requestContent);
} catch (Exception e) {
log.error(e.getMessage(), e);
}
}
/**
* 解析并查找方法对应的文件描述
*/
private static Descriptors.FileDescriptor getFileDescriptor(List<ByteString> fileDescriptorProtoList,
String packageName,
String serviceName) throws Exception {
Map<String, DescriptorProtos.FileDescriptorProto> fileDescriptorProtoMap =
fileDescriptorProtoList.stream()
.map(bs -> {
try {
return DescriptorProtos.FileDescriptorProto.parseFrom(bs);
} catch (InvalidProtocolBufferException e) {
e.printStackTrace();
}
return null;
})
.filter(Objects::nonNull)
.collect(Collectors.toMap(DescriptorProtos.FileDescriptorProto::getName, f -> f));
if (fileDescriptorProtoMap.isEmpty()) {
log.error("服务不存在");
throw new IllegalArgumentException("方法的文件描述不存在");
}
// 查找服务对应的 Proto 描述
DescriptorProtos.FileDescriptorProto fileDescriptorProto = findServiceFileDescriptorProto(packageName, serviceName, fileDescriptorProtoMap);
// 获取这个 Proto 的依赖
Descriptors.FileDescriptor[] dependencies = getDependencies(fileDescriptorProto, fileDescriptorProtoMap);
// 生成 Proto 的 FileDescriptor
return Descriptors.FileDescriptor.buildFrom(fileDescriptorProto, dependencies);
}
/**
* 根据包名和服务名查找相应的文件描述
*/
private static DescriptorProtos.FileDescriptorProto findServiceFileDescriptorProto(String packageName,
String serviceName,
Map<String, DescriptorProtos.FileDescriptorProto> fileDescriptorProtoMap) {
for (DescriptorProtos.FileDescriptorProto proto : fileDescriptorProtoMap.values()) {
if (proto.getPackage().equals(packageName)) {
boolean exist = proto.getServiceList()
.stream()
.anyMatch(s -> serviceName.equals(s.getName()));
if (exist) {
return proto;
}
}
}
throw new IllegalArgumentException("服务不存在");
}
/**
* 获取前缀
*/
private static String extraPrefix(String content) {
int index = content.lastIndexOf(".");
return content.substring(0, index);
}
/**
* 获取后缀
*/
private static String extraSuffix(String content) {
int index = content.lastIndexOf(".");
return content.substring(index + 1);
}
/**
* 获取依赖类型
*/
private static Descriptors.FileDescriptor[] getDependencies(DescriptorProtos.FileDescriptorProto proto,
Map<String, DescriptorProtos.FileDescriptorProto> finalDescriptorProtoMap) {
return proto.getDependencyList()
.stream()
.map(finalDescriptorProtoMap::get)
.map(f -> toFileDescriptor(f, getDependencies(f, finalDescriptorProtoMap)))
.toArray(Descriptors.FileDescriptor[]::new);
}
/**
* 将 FileDescriptorProto 转为 FileDescriptor
*/
#SneakyThrows
private static Descriptors.FileDescriptor toFileDescriptor(DescriptorProtos.FileDescriptorProto fileDescriptorProto,
Descriptors.FileDescriptor[] dependencies) {
return Descriptors.FileDescriptor.buildFrom(fileDescriptorProto, dependencies);
}
/**
* 执行方法调用
*/
private static void executeCall(ManagedChannel channel,
Descriptors.FileDescriptor fileDescriptor,
Descriptors.MethodDescriptor originMethodDescriptor,
String requestContent) throws Exception {
// 重新生成 MethodDescriptor
MethodDescriptor<DynamicMessage, DynamicMessage> methodDescriptor = generateMethodDescriptor(originMethodDescriptor);
CallOptions callOptions = CallOptions.DEFAULT;
TypeRegistry registry = TypeRegistry.newBuilder()
.add(fileDescriptor.getMessageTypes())
.build();
// 将请求内容由 JSON 字符串转为相应的类型
JsonFormat.Parser parser = JsonFormat.parser().usingTypeRegistry(registry);
DynamicMessage.Builder messageBuilder = DynamicMessage.newBuilder(originMethodDescriptor.getInputType());
parser.merge(requestContent, messageBuilder);
DynamicMessage requestMessage = messageBuilder.build();
// 调用，调用方式可以通过 originMethodDescriptor.isClientStreaming() 和 originMethodDescriptor.isServerStreaming() 推断
DynamicMessage response = ClientCalls.blockingUnaryCall(channel, methodDescriptor, callOptions, requestMessage);
// 将响应解析为 JSON 字符串
JsonFormat.Printer printer = JsonFormat.printer()
.usingTypeRegistry(registry)
.includingDefaultValueFields();
String responseContent = printer.print(response);
log.info("响应: {}", responseContent);
}
/**
* 重新生成方法描述
*/
private static MethodDescriptor<DynamicMessage, DynamicMessage> generateMethodDescriptor(Descriptors.MethodDescriptor originMethodDescriptor) {
// 生成方法全名
String fullMethodName = MethodDescriptor.generateFullMethodName(originMethodDescriptor.getService().getFullName(), originMethodDescriptor.getName());
// 请求和响应类型
MethodDescriptor.Marshaller<DynamicMessage> inputTypeMarshaller = ProtoUtils.marshaller(DynamicMessage.newBuilder(originMethodDescriptor.getInputType())
.buildPartial());
MethodDescriptor.Marshaller<DynamicMessage> outputTypeMarshaller = ProtoUtils.marshaller(DynamicMessage.newBuilder(originMethodDescriptor.getOutputType())
.buildPartial());
// 生成方法描述, originMethodDescriptor 的 fullMethodName 不正确
return MethodDescriptor.<DynamicMessage, DynamicMessage>newBuilder()
.setFullMethodName(fullMethodName)
.setRequestMarshaller(inputTypeMarshaller)
.setResponseMarshaller(outputTypeMarshaller)
// 使用 UNKNOWN，自动修改
.setType(MethodDescriptor.MethodType.UNKNOWN)
.build();
}
}
There isn't much to prevent this technically. The two big hurdles are:
having a runtime-callable parser for reading the .proto, and
having a general purpose gRPC client available that takes things like the service method name as literals
Both are possible, but neither is trivial.
For 1, the crude way would be to shell/invoke protoc using the descriptor-set option to generate a schema binary, then deserialize that as a FileDescriptorSet (from descriptor.proto); this model gives you access to how protoc sees the file. Some platforms also have native parsers (essentially reimplementing protoc as a library in that platform), for example protobuf-net.Reflection does this in .NET-land
For 2, here's an implementation of that in C#. The approach should be fairly portable to Java, even if the details vary. You can look at a generated implementation to see how it works in any particular language.
(Sorry that the specific examples are C#/.NET, but that's where I live; the approaches should be portable, even if the specific code: not directly)
technically both are possible.
The codegen is simply generating a handful of classes; mainly protobuf messages, grpc method descriptors and stubs. You can implement it or check in the generated code to bypass the codegen. i am not sure what is the benefit of doing this tbh. Also, it will be very annoying if the proto is changed.
It is also possible to do it dynamically using byte codegen as long as you check-in some interfaces/abstract classes to represent those generated stub/method descriptors and protobuf messages. you have to make sure those non dynamic code is in sync with the proto definition though (most likely runtime check/exception).
Related
I try to get some data from a dbus service and work with it in Java.
I can get the information in cli with the following command:
dbus-send --print-reply --system --dest=com.victronenergy.solarcharger.ttyUSB0 /Dc/0/Voltage com.victronenergy.BusItem.GetValue
The result is:
method return time=1538903662.321580 sender=:1.14 -> destination=:1.806 serial=335692 reply_serial=2
variant double 13.43
What I tried to get this data in Java, is:
After hours of reading, I created an Interface.
package javadbus;
import java.util.Map;
import org.freedesktop.dbus.DBusInterface;
import org.freedesktop.dbus.DBusSignal;
import org.freedesktop.dbus.Variant;
import org.freedesktop.dbus.exceptions.DBusException;
public interface BusItem extends DBusInterface
{
public static class PropertiesChanged extends DBusSignal
{
public final Map<String,Variant> changes;
public PropertiesChanged(String path, Map<String,Variant> changes) throws DBusException
{
super(path, changes);
this.changes = changes;
}
}
public String GetDescription(String language, int length);
public Variant GetValue();
public String GetText();
public int SetValue(Variant value);
public Variant GetMin();
public Variant GetMax();
public int SetDefault();
public Variant GetDefault();
}
Here I call getConnection() and getRemoteObject() successfully.
package javadbus;
import org.freedesktop.dbus.DBusConnection;
import org.freedesktop.dbus.exceptions.DBusException;
import org.freedesktop.dbus.Variant;
public class VictronEnergyDBusSolarCharger {
private String port;
private DBusConnection conn;
public VictronEnergyDBusSolarCharger(String port) {
this.port = port;
try {
this.conn = DBusConnection.getConnection(DBusConnection.SYSTEM);
} catch (DBusException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private String getData(String item) {
BusItem bi;
String data = null;
Variant vData = null;
try {
bi = (BusItem)conn.getRemoteObject("com.victronenergy.solarcharger." + this.port, item, BusItem.class);
vData = bi.GetValue();
//data = bi.GetText();
} catch (DBusException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return data;
}
...
}
It was a big task to resolve all dependecies and get the code compiled. But finaly I did it. So, javac now runs without errors.
But if I try to call the Method GetValue(), I get the following Exception:
[Sender] INFO org.freedesktop.dbus.MessageWriter - <= MethodCall(0,1) { Path=>/org/freedesktop/DBus, Interface=>org.freedesktop.DBus, Member=>Hello, Destination=>org.freedesktop.DBus } { }
[Sender] INFO org.freedesktop.dbus.MessageWriter - <= MethodCall(0,3) { Path=>/Dc/0/Voltage, Interface=>javadbus.BusItem, Member=>GetValue, Destination=>com.victronenergy.solarcharger.ttyUSB0 } { }
Exception in thread "main" org.freedesktop.DBus$Error$UnknownMethod: Method "GetValue" with signature "" on interface "javadbus.BusItem" doesn't exist
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at org.freedesktop.dbus.Error.getException(Error.java:141)
at org.freedesktop.dbus.Error.throwException(Error.java:171)
at org.freedesktop.dbus.RemoteInvocationHandler.executeRemoteMethod(RemoteInvocationHandler.java:158)
at org.freedesktop.dbus.RemoteInvocationHandler.invoke(RemoteInvocationHandler.java:222)
at com.sun.proxy.$Proxy1.GetValue(Unknown Source)
at javadbus.VictronEnergyDBusSolarCharger.getData(VictronEnergyDBusSolarCharger.java:28)
at javadbus.VictronEnergyDBusSolarCharger.getDcV(VictronEnergyDBusSolarCharger.java:38)
at javadbus.MainClass.main(MainClass.java:7)
Is it necessary to make a implementation of this Method GetValue? But why e.g. how should I do this? I only want to get this Information and not provide it like a Server.
Why was it a big task to get all dependencies?
dbus-java library and dependencies are all available at maven central, so a proper maven project should just work out-of-the-box.
Back to topic:
You don't have to implement GetValue(), but you need a suitable java interface for BusItem.
As far as I can see in the documentation of victronenergy (https://www.victronenergy.com/live/open_source:ccgx:d-bus) , your interface is not correct.
You provide SetDefault()/GetDefault() methods, which are only available on com.victronenergy.settings Objects, but you want to retrieve a com.victronenergy.BusItem (no part of the com.victronenergy.settings package).
This is one error. The second error is: you use the wrong package name for your BusItem class.
In your case DBus will try to resolve an object with the path javadbus.BusItem which is not provided by the connected BusAddress com.victronenergy.solarcharger.ttyUSB0.
The BusItem class has to be in package com.victronenergy or you have to use the annotation #DBusInterfaceName("com.victronenergy.BusItem").
The annotation will tell the DBus library to ignore the java package/class name and use the one provided in the annotation.
The Inteface BusItem had been created by CreateInterface-Script from https://dbus.freedesktop.org/doc/dbus-java/dbus-java/dbus-javase10.html and the XML from Introspect()
But you solved my real problem. I used the annotation #DBusInterfaceName("com.victronenergy.BusItem") now. No Exception anymore an i get data from my solarcharger. Thank you so much!
I am working in an XPages application with the OpenNTF Domino API to explore the Graph data modelling capabilities. As example I have taken the Teamroom that ships with IBM Domino.
I have defined a method to migrate responses documents into the Grap db but I get the error message: Cannot make a static reference to the non-static method
Here is what the method looks like:
private void migrateResponses(DFramedTransactionalGraph<DGraph> profilesGraph) {
try {
Database db = Factory.getSession().getCurrentDatabase();
View view = db.getView("responsesOnly");
DocumentCollection col = view.getAllDocuments();
System.out.println("number of docs found " + col.getCount());
for (Document response : col) {
System.out.println("form:" + response.getFormName());
System.out.println("id:" + response.getUniversalID());
org.openntf.domino.ext.Document parent = response.getParentDocument();
if (null == parent.getParentDocument()){
//has no parent document so this parent document is a MainTopic/Post
Post post = profilesGraph.addVertex(parent.getMetaversalID(), Post.class);
Response vertexResponse = profilesGraph.addVertex(response.getUniversalID(), Response.class);
vertexResponse.setSubject(response.getItemValueString("Subject"));
Post.addResponse(vertexResponse);
}
}
profilesGraph.commit();
} catch (Throwable t) {
XspOpenLogUtil.logError(t);
}
}
The error occurs in line:
Post.addResponse(vertexResponse);
Here is what my Post class looks like:
package com.wordpress.quintessens.graph.teamroom;
import org.openntf.domino.graph2.annotations.AdjacencyUnique;
import org.openntf.domino.graph2.builtin.DVertexFrame;
import com.tinkerpop.blueprints.Direction;
import com.tinkerpop.frames.Property;
import com.tinkerpop.frames.modules.typedgraph.TypeValue;
#TypeValue("post")
public interface Post extends DVertexFrame {
#Property("$$Key")
public String getKey();
#Property("subject")
public String getSubject();
#Property("subject")
public void setSubject(String n);
// real edges!
#AdjacencyUnique(label = "hasWritten", direction = Direction.OUT)
public Iterable<Profile> getAuthors();
#AdjacencyUnique(label = "hasReaction", direction = Direction.IN)
public void addResponse(Response response);
#AdjacencyUnique(label = "hasReaction", direction = Direction.IN)
public void removeResponse(Response response);
#AdjacencyUnique(label = "hasReaction", direction = Direction.IN)
public Iterable<Response> getResponses();
}
Do you have a suggestion how I should adapt my code to make it work?
Unless OpenNTF or TinkerPop are doing some kind of magic with the supplied annotations, you are attempting to call a non-static method on an interface. Are you sure that you don't want to change:
Post.addResponse(vertexResponse);
to
post.addResponse(vertexResponse);
I'm trying to create a XAdES-BES signature for a given blob. For this signature, I'd need to add two transforms on the content before it is signed: Base64 (http://www.w3.org/2000/09/xmldsig#base64) & a custom one (called optional-deflate).
The problems lies with that optional transform. I'm trying to figure out how to implement a custom Transform, register it, and finally have Xades4J use it.
So far I figured a lot (thanks Google and a lot of time), so I got roughly to this: I've got a Provider-class that, in the constructor, puts the new TransformService; In my main code I add my Provider to the Security instance; then, I try to add the transform to my actual to-be-signed object.
Unfortunately, I always get the same error:
Exception in thread "main" xades4j.UnsupportedAlgorithmException: Unsupported transform on XML Signature provider (urn:xml:sig:transform:optional-deflate)
at xades4j.production.DataObjectDescsProcessor.processTransforms(DataObjectDescsProcessor.java:194)
at xades4j.production.DataObjectDescsProcessor.process(DataObjectDescsProcessor.java:87)
at xades4j.production.SignerBES.sign(SignerBES.java:173)
at xades4j.production.SignerBES.sign(SignerBES.java:122)
at com.mycompany.Test.createXades(Test.java:199)
at com.mycompany.Test.main(Test.java:47)
Caused by: org.apache.xml.security.transforms.TransformationException: Unknown transformation. No handler installed for URI urn:xml:sig:transform:optional-deflate
Original Exception was org.apache.xml.security.transforms.InvalidTransformException: Unknown transformation. No handler installed for URI urn:xml:sig:transform:optional-deflate
at org.apache.xml.security.transforms.Transforms.addTransform(Unknown Source)
at xades4j.production.DataObjectDescsProcessor.processTransforms(DataObjectDescsProcessor.java:185)
... 5 more
So, my code looks like this (abbreviated to what I think is necessary here):
TransformService class:
package com.mycompany.security;
import java.io.OutputStream;
import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;
import javax.xml.crypto.Data;
import javax.xml.crypto.MarshalException;
import javax.xml.crypto.XMLCryptoContext;
import javax.xml.crypto.XMLStructure;
import javax.xml.crypto.dsig.TransformService;
import javax.xml.crypto.dsig.TransformException;
import javax.xml.crypto.dsig.spec.TransformParameterSpec;
public class OptionalDeflateTransform extends TransformService {
public AlgorithmParameterSpec getParameterSpec() {
return null;
}
public Data transform(Data data, XMLCryptoContext context) throws TransformException {
return null;
}
public Data transform(Data data, XMLCryptoContext context, OutputStream os) throws TransformException {
return null;
}
public boolean isFeatureSupported(String feature) {
return false;
}
public void init(TransformParameterSpec params) throws InvalidAlgorithmParameterException {}
public void marshalParams(XMLStructure parent, XMLCryptoContext context) throws MarshalException {}
public void init(XMLStructure parent, XMLCryptoContext context) throws InvalidAlgorithmParameterException {}
}
Provider subclass:
package com.mycompany.security;
import java.security.Provider;
public final class OptionalDeflateProvider extends Provider {
private static final long serialVersionUID = 8849833178389029123L;
public OptionalDeflateProvider() {
super("OptionalDeflate", 1.0, "OptionalDeflate provider 1.0 implementing the OptionalDeflate transform algorithm.");
put("TransformService.urn:xml:sig:transform:optional-deflate", "com.mycompany.security.OptionalDeflateTransform");
}
}
And finally, my main Test class, which contains the actual signing. Without that transform, it works (but well, doesn't add the transform, which is necessary). So Base64 works.
protected static void createXades(String content) throws Exception {
/*Get certificate & private key*/
Certificates c = new Certificates();
c.initSession(); //some helper class where I can get my certificate & private key for signing
/*Create a document*/
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.newDocument();
Element objectElement = doc.createElement("object");
doc.appendChild(objectElement);
Element requestElement = doc.createElement("request");
requestElement.appendChild(doc.createTextNode(content));
requestElement.setAttribute("ID", UUID.randomUUID().toString());
objectElement.appendChild(requestElement);
/*Key provider, signing profile & signer itself*/
KeyingDataProvider kp = new CustomKeyingDataProvider(c.getCertificate(), c.getPrivateKey());
XadesSigningProfile p = new XadesBesSigningProfile(kp);
p.withAlgorithmsProviderEx(new ProviderEx());
XadesSigner signer = p.newSigner();
/*Add the optional deflate provider*/
Security.addProvider(new OptionalDeflateProvider());
System.out.println("--- installed providers ---");
for (Provider pr : Security.getProviders())
System.out.println(pr.getName());
System.out.println("---");
/*Test if we can get the transformservice-instance*/
TransformService ts = TransformService.getInstance("urn:xml:sig:transform:optional-deflate", "DOM");
System.out.println(ts.getAlgorithm());
System.out.println("---");
/*Signed data*/
DataObjectDesc flatFile = new DataObjectReference("#" + requestElement.getAttribute("ID"))
.withTransform(new GenericAlgorithm("http://www.w3.org/2000/09/xmldsig#base64"))
.withTransform(new GenericAlgorithm("urn:xml:sig:transform:optional-deflate"));
SignedDataObjects dataObjs = new SignedDataObjects(flatFile);
/*Actual signing*/
signer.sign(dataObjs, objectElement);
log(objectElement.getLastChild());
}
As you can see I print some things out. I for instance logged that the installation works fine and I also logged the installed providers. I get this as output:
--- installed providers ---
SUN
SunRsaSign
SunEC
SunJSSE
SunJCE
SunJGSS
SunSASL
XMLDSig
SunPCSC
SunMSCAPI
OptionalDeflate
---
urn:xml:sig:transform:optional-deflate
---
So as far as I can see, the provider has succesfully been registered, the transformservice can be loaded without a problem, ... So I don't really see what's going on?
I've checked the source code of Xades4j as well, and what's happening internally on the line .withTransform(new GenericAlgorithm("urn:xml:sig:transform:optional-deflate")) is pretty straight forward:
import org.apache.xml.security.transforms.Transforms;
...
private Transforms processTransforms(DataObjectDesc dataObjDesc, Document document) throws UnsupportedAlgorithmException {
Collection<Algorithm> dObjTransfs = dataObjDesc.getTransforms();
if (dObjTransfs.isEmpty()) {
return null;
}
Transforms transforms = new Transforms(document);
for (Algorithm dObjTransf : dObjTransfs) {
try {
List<Node> transfParams = this.algorithmsParametersMarshaller.marshalParameters(dObjTransf, document);
if (null == transfParams) {
transforms.addTransform(dObjTransf.getUri());
} else {
transforms.addTransform(dObjTransf.getUri(), DOMHelper.nodeList(transfParams));
}
} catch (TransformationException ex) {
throw new UnsupportedAlgorithmException("Unsupported transform on XML Signature provider", dObjTransf.getUri(), ex);
}
}
return transforms;
}
The exact line throwing up the error is transforms.addTransform(dObjTransf.getUri()). This transforms object is a 'standard' apache object (org.apache.xml.security.transforms.Transforms object). So I'd guess it should be able to get the same TransformService as I do in code litteraly two lines up higher? But it isn't?
Anyone that can point me out what I'm missing? I'll be eternally grateful.
Apparently, Apache Santuario loads transforms from a internal map. There is a register
method that you probably can use to register your custom transform.
I'm trying to copy a file with java.nio.file.Files like this:
Files.copy(cfgFilePath, strTarget, StandardCopyOption.REPLACE_EXISTING);
The problem is that Eclipse says "The method copy(Path, Path, CopyOption...) in the type Files is not applicable for the arguments (File, String, StandardCopyOption)"
I'm using Eclipse and Java 7 on Win7 x64. My project is set up to use Java 1.6 compatibility.
Is there a solution to this or do I have to create something like this as a workaround:
File temp = new File(target);
if(temp.exists())
temp.delete();
Thanks.
You need to pass Path arguments as explained by the error message:
Path from = cfgFilePath.toPath(); //convert from File to Path
Path to = Paths.get(strTarget); //convert from String to Path
Files.copy(from, to, StandardCopyOption.REPLACE_EXISTING);
That assumes your strTarget is a valid path.
As a complement to #assylias' answer:
If you use Java 7, drop File entirely. What you want is Path instead.
And to get a Path object matching a path on your filesystem, you do:
Paths.get("path/to/file"); // argument may also be absolute
Get used to it real fast. Note that if you still use APIs which require File, Path has a .toFile() method.
Note that if you are in the unfortunate case where you use an API which returns File objects, you can always do:
theFileObject.toPath()
But in code of yours, use Path. Systematically. Without a second thought.
EDIT Copying a file to another using 1.6 using NIO can be done as such; note that the Closer class is inspited by Guava:
public final class Closer
implements Closeable
{
private final List<Closeable> closeables = new ArrayList<Closeable>();
// #Nullable is a JSR 305 annotation
public <T extends Closeable> T add(#Nullable final T closeable)
{
closeables.add(closeable);
return closeable;
}
public void closeQuietly()
{
try {
close();
} catch (IOException ignored) {
}
}
#Override
public void close()
throws IOException
{
IOException toThrow = null;
final List<Closeable> l = new ArrayList<Closeable>(closeables);
Collections.reverse(l);
for (final Closeable closeable: l) {
if (closeable == null)
continue;
try {
closeable.close();
} catch (IOException e) {
if (toThrow == null)
toThrow = e;
}
}
if (toThrow != null)
throw toThrow;
}
}
// Copy one file to another using NIO
public static void doCopy(final File source, final File destination)
throws IOException
{
final Closer closer = new Closer();
final RandomAccessFile src, dst;
final FileChannel in, out;
try {
src = closer.add(new RandomAccessFile(source.getCanonicalFile(), "r");
dst = closer.add(new RandomAccessFile(destination.getCanonicalFile(), "rw");
in = closer.add(src.getChannel());
out = closer.add(dst.getChannel());
in.transferTo(0L, in.size(), out);
out.force(false);
} finally {
closer.close();
}
}
package main.java;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
public class CopyFileOnExist {
public static void main(String[] args) {
Path sourceDirectory = Paths.get("C:/Users/abc/Downloads/FileNotFoundExceptionExample/append.txt");
Path targetDirectory = Paths.get("C:/Users/abc/Downloads/FileNotFoundExceptionExample/append5.txt");
//copy source to target using Files Class
try {
Files.copy(sourceDirectory, targetDirectory,StandardCopyOption.REPLACE_EXISTING);
} catch (IOException e) {
System.out.println(e.toString());
}
}
}
strTarget is a "String" object and not a "Path" object
I have a strange problem.
Using wsimport I generated als JAX-WS Code from a WSDL (in a dedicated eclipse java project). This works fine in JDK6 without any external dependencies (running in Eclipse)
I have second project where I once used Apache CXF. If I copy the Code described in 1.) into this project, suddenly not the JDK executes the JAX-WS stuff (files I generated), but rather Apache CXF.
How can I prevent Apache CXF "running" the JAX-WS stuff. (Problem is, CXF Fails to run the code...). I also completely do not understand how Apache CXF discovers these classes. I did not register them anywere?
Thank you very much!
Markus
Apache CXF (cxf-rt-frontend-jaxws-*.jar to be precise) registers itself as a JAX-WS provider in the JVM. Inside the aforementioned JAR there is a file named: /META-INF/services/javax.xml.ws.spi.Provider with the following contents:
org.apache.cxf.jaxws.spi.ProviderImpl
If you now look at javax.xml.ws.spi.FactoryFinder#find method you will discover that JDK searches the CLASSPATH for the presence of javax.xml.ws.spi.Provider file and falls back to default Sun implementation if not available. So you have two options to force fallback:
either remove cxf-rt-frontend-jaxws-*.jar from CLASSPATH
or override javax.xml.ws.spi.Provider file provided by CXF to point to fallback location
The second option is actually a bit easier. Simply create:
/src/main/resources/META-INF/services/javax.xml.ws.spi.Provider
file (assuming you are using Maven) with the following contents:
org.apache.cxf.jaxws.spi.ProviderImpl
That's it, tested with javax.xml.ws.Endpoint#publish.
For the default implementation put:
com.sun.xml.internal.ws.spi.ProviderImpl
inside /src/main/resources/META-INF/services/javax.xml.ws.spi.Provider
I tried the other and I just couldn't make it work at all, so to set CXF if it was not set to CXF, I just override the delegate inside the service.
try {
loc = this.getClass().getResource(wsdlResource);
QName qName = new QName( wsTargetNamespace, wsName );
service = new YourWS(loc, qName);
Field delegateField = Service.class.getDeclaredField("delegate"); //ALLOW CXF SPECIFIC SERVICE DELEGATE ONLY!
delegateField.setAccessible(true);
ServiceDelegate previousDelegate = (ServiceDelegate) delegateField.get(service);
if (!previousDelegate.getClass().getName().contains("cxf")) {
ServiceDelegate serviceDelegate = ((Provider) Class.forName("org.apache.cxf.jaxws.spi.ProviderImpl").newInstance())
.createServiceDelegate(loc, qName, service.getClass());
log.info("The " + getClass().getSimpleName() + " delegate is changed from " + "[" + previousDelegate + "] to [" +
serviceDelegate +
"]");
delegateField.set(service, serviceDelegate);
}
port = service.getYourWSSoap();
The standard finding mechanisms don't seem to work nicely in OSGi (*).
There are two ways I've gotten to work forcing the service to pick up the CXF implementation of javax.xml.ws.spi.Provider:
the approach of setting delegate by reflection given in EpicPandaForce's answer to this question (https://stackoverflow.com/a/31892305/109079)
calling the lower-level JaxWsProxyFactoryBean; this seems to avoid all calls to the javax.xml.ws.spi.FactoryFinder included with Java which is the root of the problem
Here is an example of the latter, for less intrepid coders who prefer not reflectively changing private fields:
JaxWsProxyFactoryBean factory = new JaxWsProxyFactoryBean();
factory.getClientFactoryBean().getServiceFactory().setWsdlURL(WinRmService.WSDL_LOCATION);
factory.setServiceName(WinRmService.SERVICE);
factory.setEndpointName(WinRmService.WinRmPort);
// factory.setFeatures(...); // if required
Service winrm = factory.create(WinRm.class);
Client client = ClientProxy.getClient(winrm);
A couple of notes:
Passing a URL as above, rather than the simpler factory.setWsdlURL(String) may be needed if the WSDL is a resource on the classpath (avoid unresolvable bundle://... URLs for classpath items)
You may need additional bundles for features (such as addressing)
(*) As for why the finding mechanisms don't work in most OSGi containers, check out this little bit of nasty in Oracle Java's FactoryFinder:
private static final String OSGI_SERVICE_LOADER_CLASS_NAME = "com.sun.org.glassfish.hk2.osgiresourcelocator.ServiceLoader";
private static boolean isOsgi() {
try {
Class.forName(OSGI_SERVICE_LOADER_CLASS_NAME);
return true;
} catch (ClassNotFoundException ignored) {
}
return false;
}
OSGi = Glassfish? Fishy indeed!
I had a similar problem. In my case I had to use org.apache.cxf.jaxws.spi.ProviderImpl for JAX-WS stuff (creating webservice endpoints etc.) and com.sun.xml.internal.ws.spi.ProviderImpl for publishing endpoints on com.sun.net.httpserver.HttpsServer.
I managed to solve this by creating my own provider which extends javax.xml.ws.spi.Provider and using it instead of the default one.
package provider;
import java.net.URL;
import java.util.List;
import javax.xml.namespace.QName;
import javax.xml.transform.Source;
import javax.xml.ws.Endpoint;
import javax.xml.ws.EndpointReference;
import javax.xml.ws.WebServiceFeature;
import javax.xml.ws.spi.Provider;
import javax.xml.ws.spi.ServiceDelegate;
import javax.xml.ws.wsaddressing.W3CEndpointReference;
import org.w3c.dom.Element;
public class MyProvider extends Provider
{
#SuppressWarnings({ "rawtypes", "unchecked" })
#Override
public ServiceDelegate createServiceDelegate(URL wsdlDocumentLocation, QName serviceName, Class serviceClass)
{
try {
return ((Provider) Class.forName("org.apache.cxf.jaxws.spi.ProviderImpl").newInstance()).createServiceDelegate(wsdlDocumentLocation, serviceName, serviceClass.getClass());
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public Endpoint createEndpoint(String bindingId, Object implementor)
{
try {
return ((Provider) Class.forName("com.sun.xml.internal.ws.spi.ProviderImpl").newInstance()).createEndpoint(bindingId, implementor);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public Endpoint createAndPublishEndpoint(String address, Object implementor)
{
try {
return ((Provider) Class.forName("com.sun.xml.internal.ws.spi.ProviderImpl").newInstance()).createAndPublishEndpoint(address, implementor);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public EndpointReference readEndpointReference(Source eprInfoset)
{
try {
return ((Provider) Class.forName("org.apache.cxf.jaxws.spi.ProviderImpl").newInstance()).readEndpointReference(eprInfoset);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public <T> T getPort(EndpointReference endpointReference, Class<T> serviceEndpointInterface, WebServiceFeature... features)
{
try {
return ((Provider) Class.forName("org.apache.cxf.jaxws.spi.ProviderImpl").newInstance()).getPort(endpointReference, serviceEndpointInterface, features);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public W3CEndpointReference createW3CEndpointReference(String address, QName serviceName, QName portName, List<Element> metadata, String wsdlDocumentLocation, List<Element> referenceParameters)
{
try {
return ((Provider) Class.forName("org.apache.cxf.jaxws.spi.ProviderImpl").newInstance()).createW3CEndpointReference(address, serviceName, portName, metadata, wsdlDocumentLocation,
referenceParameters);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
Then simply create:
/src/main/resources/META-INF/services/javax.xml.ws.spi.Provider
file (assuming you are using Maven) with the following contents:
package.MyProvider