Apache
/
jclouds
mirror of https://github.com/apache/jclouds.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Generalized the Arg0ToPagedIterable to propagate all args 

Generalized the Arg0ToPagedIterable to allow to propagating
all arguments. This will help building PagedIterables for
api methods that require more than one argument to be invoked.
This commit is contained in:
Ignasi Barrera 2013-07-22 16:05:02 +02:00
parent c64c7423cd
commit 4621176516
4 changed files with 263 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
core/src/main/java/org/jclouds/collect/internal/Arg0ToPagedIterable.java
View File

@ -16,15 +16,10 @@
*/
package org.jclouds.collect.internal;
import static org.jclouds.collect.PagedIterables.advance;
import static org.jclouds.collect.PagedIterables.onlyPage;
import java.util.List;
import org.jclouds.collect.IterableWithMarker;
import org.jclouds.collect.PagedIterable;
import org.jclouds.http.HttpRequest;
import org.jclouds.rest.InvocationContext;
import org.jclouds.rest.internal.GeneratedHttpRequest;
import com.google.common.annotations.Beta;
@ -38,22 +33,12 @@ import com.google.common.base.Optional;
* @author Adrian Cole
*/
@Beta
public abstract class Arg0ToPagedIterable<T, I extends Arg0ToPagedIterable<T, I>> implements
Function<IterableWithMarker<T>, PagedIterable<T>>, InvocationContext<I> {
private GeneratedHttpRequest request;
public abstract class Arg0ToPagedIterable<T, I extends Arg0ToPagedIterable<T, I>> extends ArgsToPagedIterable<T, I> {
@Override
public PagedIterable<T> apply(IterableWithMarker<T> input) {
if (!input.nextMarker().isPresent())
return onlyPage(input);
List<Object> args = getArgs(request);
protected Function<Object, IterableWithMarker<T>> markerToNextForArgs(List<Object> args) {
Optional<Object> arg0 = Optional.fromNullable(args.size() > 0 ? args.get(0) : null);
return advance(input, markerToNextForArg0(arg0));
}
protected List<Object> getArgs(GeneratedHttpRequest request) {
return request.getInvocation().getArgs();
return markerToNextForArg0(arg0);
}
/**
@ -62,13 +47,6 @@ public abstract class Arg0ToPagedIterable<T, I extends Arg0ToPagedIterable<T, I>
*/
protected abstract Function<Object, IterableWithMarker<T>> markerToNextForArg0(Optional<Object> arg0);
@SuppressWarnings("unchecked")
@Override
public I setContext(HttpRequest request) {
this.request = GeneratedHttpRequest.class.cast(request);
return (I) this;
}
/**
* Used to propagate caller {@code arg0} to a callee during an advance in a {@link PagedIterable}. For example, in
* the call {@code api.getUserApiForZone(zone).list()}, the caller arg0 is the value of {@code zone}, and the callee

91
core/src/main/java/org/jclouds/collect/internal/ArgsToPagedIterable.java Normal file
View File

@ -0,0 +1,91 @@
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jclouds.collect.internal;
import static com.google.common.base.Preconditions.checkArgument;
import static org.jclouds.collect.PagedIterables.advance;
import static org.jclouds.collect.PagedIterables.onlyPage;
import java.util.List;
import org.jclouds.collect.IterableWithMarker;
import org.jclouds.collect.PagedIterable;
import org.jclouds.http.HttpRequest;
import org.jclouds.rest.InvocationContext;
import org.jclouds.rest.internal.GeneratedHttpRequest;
import com.google.common.annotations.Beta;
import com.google.common.base.Function;
/**
* Used to propagate the invoked method arguments during an advance in a
* {@link PagedIterable}.
* <p>
* In order to fetch the next page in the result set, subclasses may need to
* have the context of the initial request. This class propagates the arguments
* used in the original request, so they can be used to fetch the next page in
* the result set.
*
* @author Ignasi Barrera
*/
@Beta
public abstract class ArgsToPagedIterable<T, I extends ArgsToPagedIterable<T, I>> implements
Function<IterableWithMarker<T>, PagedIterable<T>>, InvocationContext<I> {
protected GeneratedHttpRequest request;
@Override
public PagedIterable<T> apply(IterableWithMarker<T> input) {
return input.nextMarker().isPresent() ? advance(input, markerToNextForArgs(getArgs(request))) : onlyPage(input);
}
protected List<Object> getArgs(GeneratedHttpRequest request) {
return request.getInvocation().getArgs();
}
protected abstract Function<Object, IterableWithMarker<T>> markerToNextForArgs(List<Object> args);
@SuppressWarnings("unchecked")
@Override
public I setContext(HttpRequest request) {
checkArgument(request instanceof GeneratedHttpRequest,
"ArgsToPagedIterable only supports a GeneratedHttpRequest");
this.request = GeneratedHttpRequest.class.cast(request);
return (I) this;
}
/**
* Sometimes the arguments in the invoked method do not provide enough
* information to fetch the next page of the result set. This, for example,
* is common in APIs dealing with several endpoints.
* <p>
* This class provides a way to propagate the arguments passed to the caller
* of the method, so they can be used to fetch the next page of the result
* set. For example, in the call {@code api.getUserApiForZone(zone).list()},
* the caller arg0 is the value of {@code zone}, and the callee is
* {@code UserApi.list()}
*
* @author Adrian Cole
* @see ParseImages function in openstack-glance for a usage example.
*/
public abstract static class FromCaller<T, I extends FromCaller<T, I>> extends ArgsToPagedIterable<T, I> {
@Override
protected List<Object> getArgs(GeneratedHttpRequest request) {
return request.getCaller().get().getArgs();
}
}
}

2
core/src/test/java/org/jclouds/collect/internal/Arg0ToPagedIterableTest.java
View File

@ -53,7 +53,7 @@ public class Arg0ToPagedIterableTest {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArg0(Optional<Object> arg0) {
fail();
fail("The Iterable should not advance");
return null;
}

168
core/src/test/java/org/jclouds/collect/internal/ArgsToPagedIterableTest.java Normal file
View File

@ -0,0 +1,168 @@
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jclouds.collect.internal;
import static com.google.common.base.Throwables.propagate;
import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertTrue;
import static org.testng.Assert.fail;
import java.util.List;
import org.jclouds.collect.IterableWithMarker;
import org.jclouds.collect.IterableWithMarkers;
import org.jclouds.reflect.Invocation;
import org.jclouds.rest.internal.GeneratedHttpRequest;
import org.testng.annotations.Test;
import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import com.google.common.reflect.Invokable;
/**
* @author Ignasi Barrera
*/
@Test(testName = "ArgsToPagedIterableTest")
public class ArgsToPagedIterableTest {
private abstract static class TestArgs extends ArgsToPagedIterable<String, TestArgs> {
private TestArgs(GeneratedHttpRequest in) {
this.setContext(in);
}
}
@Test
public void testWhenNextMarkerAbsentDoesntAdvance() {
GeneratedHttpRequest request = args(ImmutableList.of());
TestArgs converter = new TestArgs(request) {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArgs(List<Object> args) {
fail("The Iterable should not advance");
return null;
}
};
assertEquals(converter.apply(IterableWithMarkers.from(ImmutableSet.of("foo", "bar"))).concat().toSet(),
ImmutableSet.of("foo", "bar"));
}
@Test
public void testWhenNextMarkerPresentButNoArgsMarkerToNextForArgsParamIsAbsent() {
GeneratedHttpRequest request = args(ImmutableList.of());
final IterableWithMarker<String> next = IterableWithMarkers.from(ImmutableSet.of("baz"));
TestArgs converter = new TestArgs(request) {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArgs(List<Object> args) {
assertTrue(args.isEmpty());
return Functions.constant(next);
}
};
assertEquals(converter.apply(IterableWithMarkers.from(ImmutableSet.of("foo", "bar"), "marker")).concat().toSet(),
ImmutableSet.of("foo", "bar", "baz"));
}
@Test
public void testWhenNextMarkerPresentWithArgsMarkerToNextForArgsParamIsPresent() {
GeneratedHttpRequest request = args(ImmutableList.<Object> of("path"));
final IterableWithMarker<String> next = IterableWithMarkers.from(ImmutableSet.of("baz"));
TestArgs converter = new TestArgs(request) {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArgs(List<Object> args) {
assertEquals(args.get(0), "path");
return Functions.constant(next);
}
};
assertEquals(converter.apply(IterableWithMarkers.from(ImmutableSet.of("foo", "bar"), "marker")).concat().toSet(),
ImmutableSet.of("foo", "bar", "baz"));
}
private GeneratedHttpRequest args(ImmutableList<Object> args) {
try {
return GeneratedHttpRequest.builder().method("GET").endpoint("http://localhost")
.invocation(Invocation.create(Invokable.from(String.class.getMethod("toString")), args)).build();
} catch (Exception e) {
throw propagate(e);
}
}
private abstract static class TestCallerArgs extends ArgsToPagedIterable.FromCaller<String, TestCallerArgs> {
private TestCallerArgs(GeneratedHttpRequest in) {
this.setContext(in);
}
}
@Test
public void testFromCallerWhenNextMarkerPresentButNoArgsMarkerToNextForArgsParamIsAbsent() {
GeneratedHttpRequest request = callerArgs(ImmutableList.of());
final IterableWithMarker<String> next = IterableWithMarkers.from(ImmutableSet.of("baz"));
TestCallerArgs converter = new TestCallerArgs(request) {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArgs(List<Object> args) {
assertTrue(args.isEmpty());
return Functions.constant(next);
}
};
assertEquals(converter.apply(IterableWithMarkers.from(ImmutableSet.of("foo", "bar"), "marker")).concat().toSet(),
ImmutableSet.of("foo", "bar", "baz"));
}
@Test
public void testFromCallerWhenNextMarkerPresentWithArgsMarkerToNextForArgsParamIsPresent() {
GeneratedHttpRequest request = callerArgs(ImmutableList.<Object> of("path"));
final IterableWithMarker<String> next = IterableWithMarkers.from(ImmutableSet.of("baz"));
TestCallerArgs converter = new TestCallerArgs(request) {
@Override
protected Function<Object, IterableWithMarker<String>> markerToNextForArgs(List<Object> args) {
assertEquals(args.get(0), "path");
return Functions.constant(next);
}
};
assertEquals(converter.apply(IterableWithMarkers.from(ImmutableSet.of("foo", "bar"), "marker")).concat().toSet(),
ImmutableSet.of("foo", "bar", "baz"));
}
private GeneratedHttpRequest callerArgs(ImmutableList<Object> args) {
try {
return GeneratedHttpRequest.builder().method("GET").endpoint("http://localhost")
.invocation(Invocation.create(Invokable.from(String.class.getMethod("toString"))))
.caller(Invocation.create(Invokable.from(String.class.getMethod("toString")), args)).build();
} catch (Exception e) {
throw propagate(e);
}
}
}