/*
* 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.apache.jackrabbit.mk.core;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import org.apache.jackrabbit.mk.api.MicroKernel;
import org.apache.jackrabbit.mk.api.MicroKernelException;
import org.apache.jackrabbit.mk.json.JsopBuilder;
import org.apache.jackrabbit.mk.json.JsopReader;
import org.apache.jackrabbit.mk.json.JsopTokenizer;
import org.apache.jackrabbit.mk.model.ChildNodeEntry;
import org.apache.jackrabbit.mk.model.Commit;
import org.apache.jackrabbit.mk.model.CommitBuilder;
import org.apache.jackrabbit.mk.model.CommitBuilder.NodeTree;
import org.apache.jackrabbit.mk.model.DiffBuilder;
import org.apache.jackrabbit.mk.model.Id;
import org.apache.jackrabbit.mk.model.NodeState;
import org.apache.jackrabbit.mk.model.PropertyState;
import org.apache.jackrabbit.mk.model.StoredCommit;
import org.apache.jackrabbit.mk.util.CommitGate;
import org.apache.jackrabbit.oak.commons.PathUtils;
/**
*
*/
public class MicroKernelImpl implements MicroKernel {
protected Repository rep;
private final CommitGate gate = new CommitGate();
public MicroKernelImpl(String homeDir) throws MicroKernelException {
init(homeDir);
}
/**
* Creates a new in-memory kernel instance that doesn't need to be
* explicitly closed, i.e. standard Java garbage collection will take
* care of releasing any acquired resources when no longer needed.
* Useful especially for test cases and other similar scenarios.
*/
public MicroKernelImpl() {
this(new Repository());
}
/**
* Alternate constructor, used for testing.
*
* @param rep repository, already initialized
*/
public MicroKernelImpl(Repository rep) {
this.rep = rep;
}
protected void init(String homeDir) throws MicroKernelException {
try {
rep = new Repository(homeDir);
rep.init();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public void dispose() {
gate.commit("end");
if (rep != null) {
try {
rep.shutDown();
} catch (Exception ignore) {
// fail silently
}
rep = null;
}
}
public String getHeadRevision() throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
return getHeadRevisionId().toString();
}
/**
* Same as {@code getHeadRevisionId}, with typed {@code Id} return value instead of string.
*
* @see #getHeadRevision()
*/
private Id getHeadRevisionId() throws MicroKernelException {
try {
return rep.getHeadRevision();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public String getRevisionHistory(long since, int maxEntries) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
maxEntries = maxEntries < 0 ? Integer.MAX_VALUE : maxEntries;
List<StoredCommit> history = new ArrayList<StoredCommit>();
try {
StoredCommit commit = rep.getHeadCommit();
while (commit != null
&& history.size() < maxEntries
&& commit.getCommitTS() >= since) {
history.add(commit);
Id commitId = commit.getParentId();
if (commitId == null) {
break;
}
commit = rep.getCommit(commitId);
}
} catch (Exception e) {
throw new MicroKernelException(e);
}
JsopBuilder buff = new JsopBuilder().array();
for (int i = history.size() - 1; i >= 0; i--) {
StoredCommit commit = history.get(i);
buff.object().
key("id").value(commit.getId().toString()).
key("ts").value(commit.getCommitTS()).
key("msg").value(commit.getMsg()).
endObject();
}
return buff.endArray().toString();
}
public String waitForCommit(String oldHeadRevisionId, long maxWaitMillis) throws MicroKernelException, InterruptedException {
return gate.waitForCommit(oldHeadRevisionId, maxWaitMillis);
}
public String getJournal(String fromRevision, String toRevision, String filter) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id fromRevisionId = Id.fromString(fromRevision);
Id toRevisionId = toRevision == null ? getHeadRevisionId() : Id.fromString(toRevision);
List<StoredCommit> commits = new ArrayList<StoredCommit>();
try {
StoredCommit toCommit = rep.getCommit(toRevisionId);
if (toCommit.getBranchRootId() != null) {
throw new MicroKernelException("branch revisions are not supported: " + toRevisionId);
}
Commit fromCommit;
if (toRevisionId.equals(fromRevisionId)) {
fromCommit = toCommit;
} else {
fromCommit = rep.getCommit(fromRevisionId);
if (fromCommit.getCommitTS() > toCommit.getCommitTS()) {
// negative range, return empty journal
return "[]";
}
}
if (fromCommit.getBranchRootId() != null) {
throw new MicroKernelException("branch revisions are not supported: " + fromRevisionId);
}
// collect commits, starting with toRevisionId
// and traversing parent commit links until we've reached
// fromRevisionId
StoredCommit commit = toCommit;
while (commit != null) {
commits.add(commit);
if (commit.getId().equals(fromRevisionId)) {
break;
}
Id commitId = commit.getParentId();
if (commitId == null) {
// inconsistent revision history, ignore silently...
break;
}
commit = rep.getCommit(commitId);
if (commit.getCommitTS() < fromCommit.getCommitTS()) {
// inconsistent revision history, ignore silently...
break;
}
}
} catch (Exception e) {
throw new MicroKernelException(e);
}
JsopBuilder commitBuff = new JsopBuilder().array();
// iterate over commits in chronological order,
// starting with oldest commit
for (int i = commits.size() - 1; i >= 0; i--) {
StoredCommit commit = commits.get(i);
if (commit.getParentId() == null) {
continue;
}
commitBuff.object().
key("id").value(commit.getId().toString()).
key("ts").value(commit.getCommitTS()).
key("msg").value(commit.getMsg()).
key("changes").value(commit.getChanges()).endObject();
}
return commitBuff.endArray().toString();
}
public String diff(String fromRevision, String toRevision, String filter) throws MicroKernelException {
// TODO extract and evaluate filter criteria (such as e.g. 'path') specified in 'filter' parameter
String path = "/";
Id fromRevisionId, toRevisionId;
if (fromRevision == null || toRevision == null) {
Id head = getHeadRevisionId();
fromRevisionId = fromRevision == null ? head : Id.fromString(fromRevision);
toRevisionId = toRevision == null ? head : Id.fromString(toRevision);
} else {
fromRevisionId = Id.fromString(fromRevision);
toRevisionId = Id.fromString(toRevision);
}
if (fromRevisionId.equals(toRevisionId)) {
return "";
}
try {
NodeState before = rep.getNodeState(fromRevisionId, path);
NodeState after = rep.getNodeState(toRevisionId, path);
return new DiffBuilder(before, after, path, rep.getRevisionStore(), filter).build();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public boolean nodeExists(String path, String revisionId) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id revId = revisionId == null ? getHeadRevisionId() : Id.fromString(revisionId);
try {
return rep.nodeExists(revId, path);
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public long getChildNodeCount(String path, String revisionId) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id revId = revisionId == null ? getHeadRevisionId() : Id.fromString(revisionId);
NodeState nodeState;
try {
nodeState = rep.getNodeState(revId, path);
} catch (Exception e) {
throw new MicroKernelException(e);
}
if (nodeState != null) {
return nodeState.getChildNodeCount();
} else {
throw new MicroKernelException("Path " + path + " not found in revision " + revisionId);
}
}
public String getNodes(String path, String revisionId) throws MicroKernelException {
return getNodes(path, revisionId, 1, 0, -1, null);
}
public String getNodes(String path, String revisionId, int depth, long offset, int count, String filter) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id revId = revisionId == null ? getHeadRevisionId() : Id.fromString(revisionId);
// TODO extract and evaluate filter criteria (such as e.g. ':hash') specified in 'filter' parameter
try {
NodeState nodeState = rep.getNodeState(revId, path);
if (nodeState == null) {
return null;
}
JsopBuilder buf = new JsopBuilder().object();
toJson(buf, nodeState, depth, (int) offset, count, true);
return buf.endObject().toString();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public String commit(String path, String jsonDiff, String revisionId, String message) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
if (path.length() > 0 && !PathUtils.isAbsolute(path)) {
throw new IllegalArgumentException("absolute path expected: " + path);
}
Id revId = revisionId == null ? getHeadRevisionId() : Id.fromString(revisionId);
try {
JsopTokenizer t = new JsopTokenizer(jsonDiff);
CommitBuilder cb = rep.getCommitBuilder(revId, message);
while (true) {
int r = t.read();
if (r == JsopReader.END) {
break;
}
int pos; // used for error reporting
switch (r) {
case '+': {
pos = t.getLastPos();
String subPath = t.readString();
t.read(':');
if (t.matches('{')) {
String nodePath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(nodePath)) {
throw new Exception("absolute path expected: " + nodePath + ", pos: " + pos);
}
String parentPath = PathUtils.getParentPath(nodePath);
String nodeName = PathUtils.getName(nodePath);
cb.addNode(parentPath, nodeName, parseNode(t));
} else {
String value;
if (t.matches(JsopReader.NULL)) {
value = null;
} else {
value = t.readRawValue().trim();
}
String targetPath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(targetPath)) {
throw new Exception("absolute path expected: " + targetPath + ", pos: " + pos);
}
String parentPath = PathUtils.getParentPath(targetPath);
String propName = PathUtils.getName(targetPath);
cb.setProperty(parentPath, propName, value);
}
break;
}
case '-': {
pos = t.getLastPos();
String subPath = t.readString();
String targetPath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(targetPath)) {
throw new Exception("absolute path expected: " + targetPath + ", pos: " + pos);
}
cb.removeNode(targetPath);
break;
}
case '^': {
pos = t.getLastPos();
String subPath = t.readString();
t.read(':');
String value;
if (t.matches(JsopReader.NULL)) {
value = null;
} else {
value = t.readRawValue().trim();
}
String targetPath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(targetPath)) {
throw new Exception("absolute path expected: " + targetPath + ", pos: " + pos);
}
String parentPath = PathUtils.getParentPath(targetPath);
String propName = PathUtils.getName(targetPath);
cb.setProperty(parentPath, propName, value);
break;
}
case '>': {
pos = t.getLastPos();
String subPath = t.readString();
String srcPath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(srcPath)) {
throw new Exception("absolute path expected: " + srcPath + ", pos: " + pos);
}
t.read(':');
pos = t.getLastPos();
String targetPath = t.readString();
if (!PathUtils.isAbsolute(targetPath)) {
targetPath = PathUtils.concat(path, targetPath);
if (!PathUtils.isAbsolute(targetPath)) {
throw new Exception("absolute path expected: " + targetPath + ", pos: " + pos);
}
}
cb.moveNode(srcPath, targetPath);
break;
}
case '*': {
pos = t.getLastPos();
String subPath = t.readString();
String srcPath = PathUtils.concat(path, subPath);
if (!PathUtils.isAbsolute(srcPath)) {
throw new Exception("absolute path expected: " + srcPath + ", pos: " + pos);
}
t.read(':');
pos = t.getLastPos();
String targetPath = t.readString();
if (!PathUtils.isAbsolute(targetPath)) {
targetPath = PathUtils.concat(path, targetPath);
if (!PathUtils.isAbsolute(targetPath)) {
throw new Exception("absolute path expected: " + targetPath + ", pos: " + pos);
}
}
cb.copyNode(srcPath, targetPath);
break;
}
default:
throw new AssertionError("token type: " + t.getTokenType());
}
}
Id newHead = cb.doCommit();
if (!newHead.equals(revId)) {
// non-empty commit
gate.commit(newHead.toString());
}
return newHead.toString();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public String branch(String trunkRevisionId) throws MicroKernelException {
// create a private branch
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id revId = trunkRevisionId == null ? getHeadRevisionId() : Id.fromString(trunkRevisionId);
try {
CommitBuilder cb = rep.getCommitBuilder(revId, "");
return cb.doCommit(true).toString();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public String merge(String branchRevisionId, String message) throws MicroKernelException {
// merge a private branch with current head revision
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
Id revId = Id.fromString(branchRevisionId);
try {
return rep.getCommitBuilder(revId, message).doMerge().toString();
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public long getLength(String blobId) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
try {
return rep.getBlobStore().getBlobLength(blobId);
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public int read(String blobId, long pos, byte[] buff, int off, int length) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
try {
return rep.getBlobStore().readBlob(blobId, pos, buff, off, length);
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
public String write(InputStream in) throws MicroKernelException {
if (rep == null) {
throw new IllegalStateException("this instance has already been disposed");
}
try {
return rep.getBlobStore().writeBlob(in);
} catch (Exception e) {
throw new MicroKernelException(e);
}
}
//-------------------------------------------------------< implementation >
void toJson(JsopBuilder builder, NodeState node, int depth, int offset, int count, boolean inclVirtualProps) {
for (PropertyState property : node.getProperties()) {
builder.key(property.getName()).encodedValue(property.getEncodedValue());
}
long childCount = node.getChildNodeCount();
if (inclVirtualProps) {
builder.key(":childNodeCount").value(childCount);
}
if (childCount > 0 && depth >= 0) {
for (ChildNodeEntry entry : node.getChildNodeEntries(offset, count)) {
builder.key(entry.getName()).object();
if (depth > 0) {
toJson(builder, entry.getNode(), depth - 1, 0, -1, inclVirtualProps);
}
builder.endObject();
}
}
}
NodeTree parseNode(JsopTokenizer t) throws Exception {
NodeTree node = new NodeTree();
if (!t.matches('}')) {
do {
String key = t.readString();
t.read(':');
if (t.matches('{')) {
node.nodes.put(key, parseNode(t));
} else {
node.props.put(key, t.readRawValue().trim());
}
} while (t.matches(','));
t.read('}');
}
return node;
}
}