access DCR from external Java class

I have created a livesite component with an external call to a java class. The DCR is passed onto this class as a parameter. It passes the following path to the Javaclass;
/templatedata/something/something/DCR

how can I retrieve the physical path to this DCR, knowing that the path is different in each context I use (preview, page preview, webserver)

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shanon

use the FileDALIfc, available from the user object.



// if using LiveSite 3.0, you must get the user from the RequestContext
// which is passed in the method signature.

EndUserIfc user = context.getUser();

// if using LiveSite 2.2.1 or prior, the user object is passed directly 
// to the method.

FileDALIfc dal = user.getFileDAL();

String path = "templatedata/Category/Type/data/file.xml";

String fullPath = dal.getRoot() + dal.getSeparator() + path;
String fileData = null;
if( dal.exists(fullPath) )
{
  fileData = dal.read(fullPath);
}

// fileData contains file contents or is null if file doesn't exist.

Here is the full FileDALIfc interface from LiveSite 3.0 ( 2.2.1 impl is *very* similar ):


public interface FileDALIfc extends XmlEmittable
{
  /*****************************************************************************
   * See if path exist
   *
   * @param path the path to the file or directory
   * @return true if file Exists
   ****************************************************************************/
  boolean exists(String path);

  /*****************************************************************************
   * See if path is a file
   *
   * @param path the path to a file
   * @return true if file Exists
   ****************************************************************************/
  boolean isFile(String path);

  /*****************************************************************************
   * See if path is directory
   *
   * @param path the path to a directory
   * @return true if file Exists
   ****************************************************************************/
  boolean isDirectory(String path);

  /*****************************************************************************
   * Read a file
   *
   * @param path the path to the file
   * @return the data read
   ****************************************************************************/
  String read(String path);

  /*****************************************************************************
   * write data to a file
   *
   * @param relativePath the path relative to the root
   * @param data the data
   *****************************************************************************/
  void write(String relativePath, String data);

  /*****************************************************************************
   * get the list of child files
   *
   * @param path the the path to the file
   * @return the list of child files
   ****************************************************************************/
  String[] getChildFiles(String path);

  /*****************************************************************************
   * get the list of child Directories
   *
   * @param path the the path to the file
   * @return the list of child Directories
   ****************************************************************************/
  String[] getChildDirectories(String path);

    /*****************************************************************************
   * Get the root directory -- points to the web root.
   *
   * @return  the web root directory.
   *****************************************************************************/
  String getRoot();

  /*****************************************************************************
   * get a file as a stream
   *
   * @param path the path to the file
   * @return the input stream
   ****************************************************************************/
  InputStream getStream(String path);

  /*****************************************************************************
   * Get the seperator
   *
   * @return the seperator
   *****************************************************************************/
  char getSeparator();
}

niske

But this is an interface. Doesn't help me very much.
Is there already a class implementing this interface?

tec_iwov

yes it is available via the user object.

from BaseExternal.getUser().getFileDAL()

TheYann

where is the documentation for this?
If we don't find this particular post how are we supposed to ever find that out?
And even if we do find this particular file, how do we know what those objects mean?

Frederik

where is the documentation for this?

Seconded!
ls.221.dg.pdf is really not covering any of the API decently :mad:

Sujay0825

I was just following this thread looking for some answers.
My requirement is that I have to read a DCR from a java program. The DCR is passed as parameter,(as you know, via the tag of ContentXML). But My question is, How do I pass the DCR parameter dynamically?. The DCR name is passed as a URL Querystring Parameter, from a main page(Summary.page) to a secondary page(Detail.page). This is to be passed as the parameter.

Any Help or Ideas?

Thanks in advance.

Bowker

I'm not 100% sure I follow you, but today I was playing around with accessing DCRs from within the Java environment.

This is probably not what you were asking, but others may need/want something like this in the future. If you find this helpful remember where you got it and pass your good fortune forward in the future.

Admittedly I didn't mess around with the DAL stuff and "hard coded" the path of where stuff is located. We won't be moving anything anytime soon.

In the Java world I have the following (I'm paraphrasing and not copy/pasting so forgive me)

Element compModel = context.getThisComponentModel();
Element data = compModel.element("Data");
I setup an iterator over data.elements("Datum") to loop through all the Datums that were defined in the component.

String dcrFilename
if (context.isPreview())
dcrFilename = "y:/default/main/branch/workarea/xxxx/";
else
dcrFilename = "/opt/interwoven/LiveSite/DisplayServices/runtime/web/";

// your paths above will be different

if iter.attribute("Name").getValue().equals("myDCR")
dcrFilename = dcrFilename + iter.element("DCR").getText()

(this can be shortened, but I have other things going on that I used an iterator. You don't really need to if you only have one DCR field in the Datums.

now you have a fully pathed filename that you can use standard Java file I/O to read. I personally read it into a org.w3c.dom.Document using a DocumentBuilder object and use the .parse(dcrFilename) method.

something like this:
DocumentBUilderFactory dbf - DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
DocumentBuilder db = dbf.newDocumentBuilder()
org.w3c.dom.Document doc = db.parse(dcrFilename);

Now in "doc" is a Document that contains the DCR content.

Sujay0825

Dan, Thanks for your suggestion. It is helpful but it is just that I still have a doubt. You said you didn't follow me correctly. So let me give a detailed explanation.
1. I have a summary.component where i have 6 images.
2. Each image is a link to a "different page".
3. I read the images from "a DCR", eg "test,test1,test2...test5".
4. Now this summary.component is added to a page called summary.page.
5. Now the links in the summary.page will send me to a detail.page.
6. In the detail.page, I have a component, detail.component.
7. This detail.component gets its value from the DCR.
8. But the name of the DCR is sent as a parameter from the summary.page to the detail.page, like $PAGE_LINK[detail]?dcrName = "test1".
9. This parameter varies based on the link I click(the Images).
10. There are no "different page".
11. Each time i click a link, the DCR from which the image is picked is sent as a parameter.
eg, If i click the first image, My redirect URL is
' $PAGE_LINK[detail]?dcrName = "test". '

Now how do I get this parameter, dcrName, and pass it to the tag of ContentXML?

Rick Poulin

Now how do I get this parameter, dcrName, and pass it to the tag of ContentXML?

[PHP]
/* In Java */
public Document myExternalCall(RequestContext context) {
String dcrName = context.getRequest().getParameter("dcrName");
if (dcrName == null || dcrName.length() == 0) {
// TODO: do something nicer than this
throw new IllegalArgumentException("DCR Name not provided");
} else {
Document out = ExternalUtils.readXmlFile(context, "templatedata/hello/world/data/" + dcrName);
if (out == null) {
// TODO: do something nicer than this
throw new IllegalArgumentException("Requested DCR not found");
}
return out;
}
}
[/PHP]

If all goes well, your DCR XML will be appended as a child of /Properties/Data/Result in your component's XML data source.

Sujay0825

If all goes well, your DCR XML will be appended as a child of /Properties/Data/Result in your component's XML data source.

Thanks a ton Rick. It worked.

Bowker

Fantastic solution.

I have one addition/comment be careful with using "dcrName" directly. It would not be impossible for someone to pass "../../../../../../someSystemFile.xml" as dcrName and possibly get information from your system.

You probably should verify there are no ".." or any other undesirable things in dcrName before you use it. It's kinda like SQL injection but not quite as bad.

It is a VERY VERY long shot that such an issue could occur (the format of the XML files would have to be similar) but our security people here get all over us for not doing this.