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First, yes I'm back, after a couple years out, I decided to reactivate this blog and now I have tons of things to talk about.
For my "Welcome back" article I'll do a very nice peace of code. The demand has started with a customer asking for a solution to read a "pom.xml" file from an Stream, increment the version number attribute and deliver it back to the stream. So I began my research and found an article from Kelvin that did help me a lot: Reading and writing files directly on a stream. And of course I found this article by the Ralph's blog tsjazz | Jazz in Flight . (which is the best blog about RTC API that I know of).
That article showed me the way, but I still had a problem, the article was all about using client API and as I said, the customer needed to do this at server side, more specifically using an IOperationParticipant. So, after some hours of digging the RTC SDK, I was able to get it done. So, here is it.
First, the method to update the file
/**
* Update the content of a file
*
* @param workItem
* @param filePath
* @param stream
* @param component
* @param myService
* @return
*/
public boolean updatePomVersion(IWorkItem workItem, String filePath, IWorkspace stream, IComponent component, AbstractService myService) {
// File pat, e.g. src/pom.xml
IPath pomPath = new Path(filePath);
// Getting services
IScmItemService scmItemService = (IScmItemService) myService.getService(IScmItemService.class);
IScmService scmService = (IScmService) myService.getService(IScmService.class);
ServiceConfigurationProvider config = ServiceConfigurationProvider.FACTORY.create(stream, component);
IServerSideVersionedContentService contentService = myService.getService(IServerSideVersionedContentService.class);
IServerSideFileContentService fileContentService = myService.getService(IServerSideFileContentService.class);
// Trying to locate the file within the component
IVersionableHandle versionableHandle;
try {
versionableHandle = scmService.configurationResolvePath(
config, component.getRootFolder(),
pomPath.segments(), null, null);
// File not found
if (versionableHandle == null) {
System.out.println("Versionable not found.");
return false;
} else {
// Fetching Versionable from its handle
IVersionable versionable = scmItemService.fetchState(versionableHandle, IScmItemService.COMPLETE);
// If not file (that is just to be safe)
if( !(versionable instanceof IFileItem ) ) {
System.out.println("Versionable is not a file"); //$NON-NLS-1$
return false;
} else {
// Reading file content
IFileItem file = (IFileItem) versionable;
IFileContent content = file.getContent();
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
contentService.fetchContentTrusted(versionableHandle, content.getHash(), outStream);
// Now that you have the content of the file in "outStream" object
// I'll skip the code to update the file content
// as this is not the goal of this article.
// Let's just assume that you have the new
// content in a new object called "newOutputStream"
// with something like:
// ByteArrayOutputStream newOutputStream = updateStreamContent(outStream);
// Updating File content
IFileItem fileWorkingCopy = (IFileItem) file.getWorkingCopy();
IFileContent newFileContent = createFileContent(newOutputStream.toByteArray(), fileContentService);
ICommitParameter param = ICommitParameter.FACTORY.create();
fileWorkingCopy.setContent((IFileContent) newFileContent);
param.addItemToSave(fileWorkingCopy);
// Applying lock and delivering
applyLock(stream, component, fileWorkingCopy, scmService);
try {
// Create change set
IChangeSetHandle cs = scmService.createChangeSetForStream(stream, component, "Changeset Comment - File content updated", param, IScmService.DELTA_PER_INVOCATION, null);
IChangeSetHandle[] csHandles = new IChangeSetHandle[1];
csHandles[0] = cs;
// Deliver
scmService.deliverCombined(null, null, stream, new IBaselineHandle[0], csHandles, null, null, null, null);
// I'll cover how to associate a changeset with an work item (server side) in another post
// So this is only to get you curious :)
// associateWorkItem(workItem, cs, stream);
return true;
} finally {
// Remove the lock
removeLock(stream, component, fileWorkingCopy, scmService);
}
}
}
} catch (Exception e) {
return false;
}
}
Now let's look at the others methods created.
Starting with the two methods to lock and unlock the file. This is necessary to create a changeset.
@SuppressWarnings("unchecked")
/**
* Lock the file
*
* @param streamHandle
* @param componentHandle
* @param fileItem
* @param scmService
* @throws TeamRepositoryException
*/
private void applyLock(IWorkspace streamHandle, IComponentHandle componentHandle, IFileItem fileItem, IScmService scmService) throws TeamRepositoryException {
// Commit parameter
ICommitParameter instruction = ICommitParameter.FACTORY.create();
instruction.addItemToSave(fileItem);
// Setting up workspace/stream, component and contributor
LockParameter operationParameter = ScmDtoFactory.eINSTANCE.createLockParameter();
WorkspaceLocks wl = ScmDtoFactory.eINSTANCE.createWorkspaceLocks();
operationParameter.getToAcquire().add(wl);
wl.setWorkspace(streamHandle);
ComponentLocks cl = ScmDtoFactory.eINSTANCE.createComponentLocks();
cl.setComponent(componentHandle);
wl.getComponentLocks().add(cl);
ContributorLocks contL = ScmDtoFactory.eINSTANCE.createContributorLocks();
contL.setContributor(getAuthenticatedContributor());
contL.getVersionables().add(fileItem);
cl.getContributorLocks().add(contL);
// Locking file
scmService.updateLocks(operationParameter , null);
}
@SuppressWarnings("unchecked")
/**
*
* @param streamHandle
* @param componentHandle
* @param fileItem
* @param scmService
* @throws TeamRepositoryException
*/
private void removeLock(IWorkspace streamHandle, IComponentHandle componentHandle, IFileItem fileItem, IScmService scmService) throws TeamRepositoryException {
// Commit parameter
ICommitParameter instruction = ICommitParameter.FACTORY.create();
instruction.addItemToSave(fileItem);
// Setting up workspace/stream, component and contributor
LockParameter operationParameter = ScmDtoFactory.eINSTANCE.createLockParameter();
WorkspaceLocks wl = ScmDtoFactory.eINSTANCE.createWorkspaceLocks();
operationParameter.getToRelease().add(wl);
wl.setWorkspace(streamHandle);
ComponentLocks cl = ScmDtoFactory.eINSTANCE.createComponentLocks();
cl.setComponent(componentHandle);
wl.getComponentLocks().add(cl);
ContributorLocks contL = ScmDtoFactory.eINSTANCE.createContributorLocks();
contL.setContributor(getAuthenticatedContributor());
contL.getVersionables().add(fileItem);
cl.getContributorLocks().add(contL);
// Removing the lock
scmService.updateLocks(operationParameter , null);
}
And lastly the method to create the file content
@SuppressWarnings("restriction")
/**
* Create an IFileContent with the bytes informed
* @param bytes Usually coming from an Input or Output Stream
* @param fileContentService Service used to store de content
* @return
* @throws TeamRepositoryException
*/
private IFileContent createFileContent(byte[] bytes, IServerSideFileContentService fileContentService) throws TeamRepositoryException {
// Generate has code
ContentHash contentHashCode;
try {
contentHashCode = ContentHash.valueOf(new UnsynchronizedByteArrayInputStream(bytes));
} catch (IOException e) {
throw new TeamRepositoryException(e);
}
// Create an Input Stream with the informed bytes
ByteArrayInputStream inStream = new ByteArrayInputStream(bytes);
// Store the content
fileContentService.storeContent(contentHashCode, bytes.length, null, IFileContent.ENCODING_UTF_8, FileLineDelimiter.LINE_DELIMITER_NONE, 0, inStream);
// Setting the file content object
FileContent c = FilesystemFactory.eINSTANCE.createFileContent();
c.setHash(contentHashCode);
c.setPredecessorHint((ContentHash)null);
c.setSize(bytes.length);
c.setCharacterEncoding(IFileContent.ENCODING_UTF_8);
c.setLineDelimiter(FileLineDelimiter.LINE_DELIMITER_NONE);
c.setLineDelimiterCount(0);
return c;
}
All the code above runs directly with in a IOperationParticipant. You'll need the follow interfaces to make it works:
<requiredservice interface="com.ibm.team.repository.service.IRepositoryItemService"> <requiredservice interface="com.ibm.team.repository.service.IServerQueryService"> <requiredservice interface="com.ibm.team.repository.service.IContentService"> <requiredservice interface="com.ibm.team.scm.common.IScmService"> <requiredservice interface="com.ibm.team.scm.service.IScmItemService"> <requiredservice interface="com.ibm.team.scm.service.IServerSideVersionedContentService"> <requiredservice interface="com.ibm.team.repository.common.service.IPermissionService"> <requiredservice interface="com.ibm.team.repository.common.service.IContributorService"> <requiredservice interface="com.ibm.team.filesystem.service.internal.IServerSideFileContentService"> <requiredservice interface="com.ibm.team.process.service.IProcessServerService"> <requiredservice interface="com.ibm.team.repository.service.ITransactionService">
That is it! Let me know if you need anything else.
