PushProcess.java
/*
* Copyright (C) 2008, 2022 Marek Zawirski <marek.zawirski@gmail.com> and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.transport;
import java.io.IOException;
import java.io.OutputStream;
import java.text.MessageFormat;
import java.util.Collection;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;
import org.eclipse.jgit.api.errors.AbortedByHookException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.errors.NotSupportedException;
import org.eclipse.jgit.errors.TransportException;
import org.eclipse.jgit.hooks.PrePushHook;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevObject;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.transport.RemoteRefUpdate.Status;
/**
* Class performing push operation on remote repository.
*
* @see Transport#push(ProgressMonitor, Collection, OutputStream)
*/
class PushProcess {
/** Task name for {@link ProgressMonitor} used during opening connection. */
static final String PROGRESS_OPENING_CONNECTION = JGitText.get().openingConnection;
/** Transport used to perform this operation. */
private final Transport transport;
/** Push operation connection created to perform this operation */
private PushConnection connection;
/** Refs to update on remote side. */
private final Map<String, RemoteRefUpdate> toPush;
/** Revision walker for checking some updates properties. */
private final RevWalk walker;
/** an outputstream to write messages to */
private final OutputStream out;
/** A list of option strings associated with this push */
private List<String> pushOptions;
private final PrePushHook prePush;
/**
* Create process for specified transport and refs updates specification.
*
* @param transport
* transport between remote and local repository, used to create
* connection.
* @param toPush
* specification of refs updates (and local tracking branches).
* @param prePush
* {@link PrePushHook} to run after the remote advertisement has
* been gotten
* @throws TransportException
*/
PushProcess(Transport transport, Collection<RemoteRefUpdate> toPush,
PrePushHook prePush) throws TransportException {
this(transport, toPush, prePush, null);
}
/**
* Create process for specified transport and refs updates specification.
*
* @param transport
* transport between remote and local repository, used to create
* connection.
* @param toPush
* specification of refs updates (and local tracking branches).
* @param prePush
* {@link PrePushHook} to run after the remote advertisement has
* been gotten
* @param out
* OutputStream to write messages to
* @throws TransportException
*/
PushProcess(Transport transport, Collection<RemoteRefUpdate> toPush,
PrePushHook prePush, OutputStream out) throws TransportException {
this.walker = new RevWalk(transport.local);
this.transport = transport;
this.toPush = new LinkedHashMap<>();
this.prePush = prePush;
this.out = out;
this.pushOptions = transport.getPushOptions();
for (RemoteRefUpdate rru : toPush) {
if (this.toPush.put(rru.getRemoteName(), rru) != null)
throw new TransportException(MessageFormat.format(
JGitText.get().duplicateRemoteRefUpdateIsIllegal, rru.getRemoteName()));
}
}
/**
* Perform push operation between local and remote repository - set remote
* refs appropriately, send needed objects and update local tracking refs.
* <p>
* When {@link Transport#isDryRun()} is true, result of this operation is
* just estimation of real operation result, no real action is performed.
*
* @param monitor
* progress monitor used for feedback about operation.
* @return result of push operation with complete status description.
* @throws NotSupportedException
* when push operation is not supported by provided transport.
* @throws TransportException
* when some error occurred during operation, like I/O, protocol
* error, or local database consistency error.
*/
PushResult execute(ProgressMonitor monitor)
throws NotSupportedException, TransportException {
try {
monitor.beginTask(PROGRESS_OPENING_CONNECTION,
ProgressMonitor.UNKNOWN);
final PushResult res = new PushResult();
connection = transport.openPush();
try {
res.setAdvertisedRefs(transport.getURI(), connection
.getRefsMap());
res.peerUserAgent = connection.getPeerUserAgent();
monitor.endTask();
Map<String, RemoteRefUpdate> expanded = expandMatching();
toPush.clear();
toPush.putAll(expanded);
res.setRemoteUpdates(toPush);
final Map<String, RemoteRefUpdate> preprocessed = prepareRemoteUpdates();
List<RemoteRefUpdate> willBeAttempted = preprocessed.values()
.stream().filter(u -> {
switch (u.getStatus()) {
case NON_EXISTING:
case REJECTED_NODELETE:
case REJECTED_NONFASTFORWARD:
case REJECTED_OTHER_REASON:
case REJECTED_REMOTE_CHANGED:
case UP_TO_DATE:
return false;
default:
return true;
}
}).collect(Collectors.toList());
if (!willBeAttempted.isEmpty()) {
if (prePush != null) {
try {
prePush.setRefs(willBeAttempted);
prePush.setDryRun(transport.isDryRun());
prePush.call();
} catch (AbortedByHookException | IOException e) {
throw new TransportException(e.getMessage(), e);
}
}
}
if (transport.isDryRun())
modifyUpdatesForDryRun();
else if (!preprocessed.isEmpty())
connection.push(monitor, preprocessed, out);
} finally {
connection.close();
res.addMessages(connection.getMessages());
}
if (!transport.isDryRun())
updateTrackingRefs();
for (RemoteRefUpdate rru : toPush.values()) {
final TrackingRefUpdate tru = rru.getTrackingRefUpdate();
if (tru != null)
res.add(tru);
}
return res;
} finally {
walker.close();
}
}
private Map<String, RemoteRefUpdate> prepareRemoteUpdates()
throws TransportException {
boolean atomic = transport.isPushAtomic();
final Map<String, RemoteRefUpdate> result = new LinkedHashMap<>();
for (RemoteRefUpdate rru : toPush.values()) {
final Ref advertisedRef = connection.getRef(rru.getRemoteName());
ObjectId advertisedOld = null;
if (advertisedRef != null) {
advertisedOld = advertisedRef.getObjectId();
}
if (advertisedOld == null) {
advertisedOld = ObjectId.zeroId();
}
if (rru.getNewObjectId().equals(advertisedOld)) {
if (rru.isDelete()) {
// ref does exist neither locally nor remotely
rru.setStatus(Status.NON_EXISTING);
} else {
// same object - nothing to do
rru.setStatus(Status.UP_TO_DATE);
}
continue;
}
// caller has explicitly specified expected old object id, while it
// has been changed in the mean time - reject
if (rru.isExpectingOldObjectId()
&& !rru.getExpectedOldObjectId().equals(advertisedOld)) {
rru.setStatus(Status.REJECTED_REMOTE_CHANGED);
if (atomic) {
return rejectAll();
}
continue;
}
if (!rru.isExpectingOldObjectId()) {
rru.setExpectedOldObjectId(advertisedOld);
}
// create ref (hasn't existed on remote side) and delete ref
// are always fast-forward commands, feasible at this level
if (advertisedOld.equals(ObjectId.zeroId()) || rru.isDelete()) {
rru.setFastForward(true);
result.put(rru.getRemoteName(), rru);
continue;
}
boolean fastForward = isFastForward(advertisedOld,
rru.getNewObjectId());
rru.setFastForward(fastForward);
if (!fastForward && !rru.isForceUpdate()) {
rru.setStatus(Status.REJECTED_NONFASTFORWARD);
if (atomic) {
return rejectAll();
}
} else {
result.put(rru.getRemoteName(), rru);
}
}
return result;
}
/**
* Determines whether an update from {@code oldOid} to {@code newOid} is a
* fast-forward update:
* <ul>
* <li>both old and new must be commits, AND</li>
* <li>both of them must be known to us and exist in the repository,
* AND</li>
* <li>the old commit must be an ancestor of the new commit.</li>
* </ul>
*
* @param oldOid
* {@link ObjectId} of the old commit
* @param newOid
* {@link ObjectId} of the new commit
* @return {@code true} if the update fast-forwards, {@code false} otherwise
* @throws TransportException
*/
private boolean isFastForward(ObjectId oldOid, ObjectId newOid)
throws TransportException {
try {
RevObject oldRev = walker.parseAny(oldOid);
RevObject newRev = walker.parseAny(newOid);
if (!(oldRev instanceof RevCommit) || !(newRev instanceof RevCommit)
|| !walker.isMergedInto((RevCommit) oldRev,
(RevCommit) newRev)) {
return false;
}
} catch (MissingObjectException x) {
return false;
} catch (Exception x) {
throw new TransportException(transport.getURI(),
MessageFormat.format(JGitText
.get().readingObjectsFromLocalRepositoryFailed,
x.getMessage()),
x);
}
return true;
}
/**
* Expands all placeholder {@link RemoteRefUpdate}s for "matching"
* {@link RefSpec}s ":" in {@link #toPush} and returns the resulting map in
* which the placeholders have been replaced by their expansion.
*
* @return a new map of {@link RemoteRefUpdate}s keyed by remote name
* @throws TransportException
* if the expansion results in duplicate updates
*/
private Map<String, RemoteRefUpdate> expandMatching()
throws TransportException {
Map<String, RemoteRefUpdate> result = new LinkedHashMap<>();
boolean hadMatch = false;
for (RemoteRefUpdate update : toPush.values()) {
if (update.isMatching()) {
if (hadMatch) {
throw new TransportException(MessageFormat.format(
JGitText.get().duplicateRemoteRefUpdateIsIllegal,
":")); //$NON-NLS-1$
}
expandMatching(result, update);
hadMatch = true;
} else if (result.put(update.getRemoteName(), update) != null) {
throw new TransportException(MessageFormat.format(
JGitText.get().duplicateRemoteRefUpdateIsIllegal,
update.getRemoteName()));
}
}
return result;
}
/**
* Expands the placeholder {@link RemoteRefUpdate} {@code match} for a
* "matching" {@link RefSpec} ":" or "+:" and puts the expansion into the
* given map {@code updates}.
*
* @param updates
* map to put the expansion in
* @param match
* the placeholder {@link RemoteRefUpdate} to expand
*
* @throws TransportException
* if the expansion results in duplicate updates, or the local
* branches cannot be determined
*/
private void expandMatching(Map<String, RemoteRefUpdate> updates,
RemoteRefUpdate match) throws TransportException {
try {
Map<String, Ref> advertisement = connection.getRefsMap();
Collection<RefSpec> fetchSpecs = match.getFetchSpecs();
boolean forceUpdate = match.isForceUpdate();
for (Ref local : transport.local.getRefDatabase()
.getRefsByPrefix(Constants.R_HEADS)) {
if (local.isSymbolic()) {
continue;
}
String name = local.getName();
Ref advertised = advertisement.get(name);
if (advertised == null || advertised.isSymbolic()) {
continue;
}
ObjectId oldOid = advertised.getObjectId();
if (oldOid == null || ObjectId.zeroId().equals(oldOid)) {
continue;
}
ObjectId newOid = local.getObjectId();
if (newOid == null || ObjectId.zeroId().equals(newOid)) {
continue;
}
RemoteRefUpdate rru = new RemoteRefUpdate(transport.local, name,
newOid, name, forceUpdate,
Transport.findTrackingRefName(name, fetchSpecs),
oldOid);
if (updates.put(rru.getRemoteName(), rru) != null) {
throw new TransportException(MessageFormat.format(
JGitText.get().duplicateRemoteRefUpdateIsIllegal,
rru.getRemoteName()));
}
}
} catch (IOException x) {
throw new TransportException(transport.getURI(),
MessageFormat.format(JGitText
.get().readingObjectsFromLocalRepositoryFailed,
x.getMessage()),
x);
}
}
private Map<String, RemoteRefUpdate> rejectAll() {
for (RemoteRefUpdate rru : toPush.values()) {
if (rru.getStatus() == Status.NOT_ATTEMPTED) {
rru.setStatus(RemoteRefUpdate.Status.REJECTED_OTHER_REASON);
rru.setMessage(JGitText.get().transactionAborted);
}
}
return Collections.emptyMap();
}
private void modifyUpdatesForDryRun() {
for (RemoteRefUpdate rru : toPush.values())
if (rru.getStatus() == Status.NOT_ATTEMPTED)
rru.setStatus(Status.OK);
}
private void updateTrackingRefs() {
for (RemoteRefUpdate rru : toPush.values()) {
final Status status = rru.getStatus();
if (rru.hasTrackingRefUpdate()
&& (status == Status.UP_TO_DATE || status == Status.OK)) {
// update local tracking branch only when there is a chance that
// it has changed; this is possible for:
// -updated (OK) status,
// -up to date (UP_TO_DATE) status
try {
rru.updateTrackingRef(walker);
} catch (IOException e) {
// ignore as RefUpdate has stored I/O error status
}
}
}
}
/**
* Gets the list of option strings associated with this push.
*
* @return pushOptions
* @since 4.5
*/
public List<String> getPushOptions() {
return pushOptions;
}
}