HTTP::DAV - A WebDAV client library for Perl5


NAME

HTTP::DAV - A WebDAV client library for Perl5


SYNOPSIS

   # DAV script that connects to a webserver, safely makes 
   # a new directory and uploads all html files in 
   # the /tmp directory.
   use HTTP::DAV;

   $d = new HTTP::DAV;
   $url = "http://host.org:8080/dav/";;

   $d->credentials( -user=>"pcollins",-pass =>"mypass", 
                    -url =>$url,      -realm=>"DAV Realm" );

   $d->open( -url=>"$url )
      or die("Couldn't open $url: " .$d->message . "\n");

   # Make a null lock on newdir
   $d->lock( -url => "$url/newdir", -timeout => "10m" ) 
      or die "Won't put unless I can lock for 10 minutes\n";
   # Make a new directory
   $d->mkcol( -url => "$url/newdir" )
      or die "Couldn't make newdir at $url\n";

   # Upload multiple files to newdir.
   if ( $d->put( -local => "/tmp/*.html", -url => $url ) ) {
      print "successfully uploaded multiple files to $url\n";
   } else {
      print "put failed: " . $d->message . "\n";
   }

   $d->unlock( -url => $url );


DESCRIPTION

HTTP::DAV is a Perl API for interacting with and modifying content on webservers using the WebDAV protocol. Now you can LOCK, DELETE and PUT files and much more on a DAV-enabled webserver.

HTTP::DAV is part of the PerlDAV project hosted at http://www.webdav.org/perldav/ and has the following features:

HTTP::DAV essentially has two API's, one which is accessed through this module directly (HTTP::DAV) and is a simple abstraction to the rest of the HTTP::DAV::* Classes. The other interface consists of the HTTP::DAV::* classes which if required allow you to get ``down and dirty'' with your DAV and HTTP interactions.

The methods provided in HTTP::DAV should do most of what you want. If, however, you need more control over the client's operations or need more info about the server's responses then you will need to understand the rest of the HTTP::DAV::* interfaces. A good place to start is with the HTTP::DAV::Resource and HTTP::DAV::Response documentation.


METHODS

METHOD CALLING: Named vs Unnamed parameters

You can pass parameters to HTTP::DAV methods in one of two ways: named or unnamed.

Named parameters provides for a simpler/easier to use interface. A named interface affords more readability and allows the developer to ignore a specific order on the parameters. (named parameters are also case insensitive)

Each argument name is preceded by a dash. Neither case nor order matters in the argument list. -url, -Url, and -URL are all acceptable. In fact, only the first argument needs to begin with a dash. If a dash is present in the first argument, HTTP::DAV assumes dashes for the subsequent ones.

Each method can also be called with unnamed parameters which often makes sense for methods with only one parameter. But the developer will need to ensure that the parameters are passed in the correct order (as listed in the docs).

 Doc:     method( -url=>$url, [-depth=>$depth] )
 Named:   $d->method( -url=>$url, -depth=>$d ); # VALID
 Named:   $d->method( -Depth=>$d, -Url=>$url ); # VALID
 Named:   $d->method( Depth=>$d,  Url=>$url );  # INVALID (needs -)
 Named:   $d->method( -Arg2=>$val2 ); # INVALID, ARG1 is not optional
 Unnamed: $d->method( $val1 );        # VALID
 Unnamed: $d->method( $val2,$val1 );  # INVALID, ARG1 must come first.

IMPORTANT POINT!!!! If you specify a named parameter first but then forget for the second and third parameters, you WILL get weird things happen. E.g. this is bad:

 $d->method( -url=>$url, $arg2, $arg3 ); # BAD BAD BAD

THINGS YOU NEED TO KNOW

In all of the methods specified in PUBLIC METHODS there are some common concepts you'll need to understand:

PUBLIC METHODS

new(USERAGENT)
Creates a new HTTP::DAV client
 $d = HTTP::DAV->new()

The -useragent parameter expects an HTTP::DAV::UserAgent object. See the dave program for an advanced example of a custom UserAgent that interactively prompts the user for their username and password.

credentials(USER,PASS,[URL],[REALM])
sets authorization credentials for a URL and/or REALM.

When the client hits a protected resource it will check these credentials to see if either the URL or REALM match the authorization response.

Either URL or REALM must be provided.

returns no value

Example:

 $d->credentials( -url=>'myhost.org:8080/test/',
                  -user=>'pcollins',
                  -pass=>'mypass');

DebugLevel($val)
sets the debug level to $val. 0=off 3=noisy.

$val default is 0.

returns no value.

When the value is greater than 1, the HTTP::DAV::Comms module will log all of the client<=>server interactions into /tmp/perldav_debug.txt.

DAV OPERATIONS

For all of the following operations, URL can be absolute (http://host.org/dav/) or relative (../dir2/). The only operation that requires an absolute URL is open.

copy(URL,DEST,[OVERWRITE],[DEPTH])
copies one remote resource to another
-url
is the remote resource you'd like to copy. Mandatory

-dest
is the remote target for the copy command. Mandatory

-overwrite
optionally indicates whether the server should fail if the target exists. Valid values are ``T'' and ``F'' (1 and 0 are synonymous). Default is T.

-depth
optionally indicates whether the server should do a recursive copy or not. Valid values are 0 and (1 or ``infinity''). Default is ``infinity'' (1).

The return value is always 1 or 0 indicating success or failure.

Requires a working resource to be set before being called. See open.

Note: if either 'URL' or 'DEST' are locked by this dav client, then the lock headers will be taken care of automatically. If the either of the two URL's are locked by someone else, the server should reject the request.

copy examples:

  $d->open(-url=>"host.org/dav_dir/");

Recursively copy dir1/ to dir2/

  $d->copy(-url=>"dir1/", -dest=>"dir2/");

Non-recursively and non-forcefully copy dir1/ to dir2/

  $d->copy(-url=>"dir1/", -dest=>"dir2/",-overwrite=>0,-depth=>0);

Create a copy of dir1/file.txt as dir2/file.txt

  $d->cwd(-url=>"dir1/");
  $d->copy("file.txt","../dir2");

Create a copy of file.txt as dir2/new_file.txt

  $d->copy("file.txt","/dav_dir/dir2/new_file.txt")
cwd(URL)
changes the remote working directory.

This is synonymous to open except that the URL can be relative and may contain a glob (the first match in a glob will be used).

  $d->open("host.org/dav_dir/dir1/");
  $d->cwd("../dir2");
  $d->cwd(-url=>"../dir1");

The return value is always 1 or 0 indicating success or failure.

Requires a working resource to be set before being called. See open.

You can not cwd to files, only collections (directories).

delete(URL)
deletes a remote resource.
  $d->open("host.org/dav_dir/");
  $d->delete("index.html");
  $d->delete("./dir1");
  $d->delete(-url=>"/dav_dir/dir2/file*",-callback=>\&mycallback);

-url
is the remote resource(s) you'd like to delete. It can be a file, directory or glob.

-callback is a reference to a callback function which will be called everytime a file is deleted. This is mainly useful when used in conjunction with GLOBS deletes. See the callbacks manpage
The return value is always 1 or 0 indicating success or failure.

Requires a working resource to be set before being called. See open.

This command will recursively delete directories. BE CAREFUL of uninitialised file variables in situation like this: $d->delete(``$dir/$file''). This will trash your $dir if $file is not set.

get(URL,[TO],[CALLBACK])
downloads the file or directory at URL to the local location indicated by TO.
-url
is the remote resource you'd like to get. It can be a file or directory or a ``glob''.

-to
is where you'd like to put the remote resource. The -to parameter can be:
 - a B<filename> indicating where to save the contents.
 - a B<FileHandle reference>.
 - a reference to a B<scalar object> into which the contents will be saved.

If the -url matches multiple files (via a glob or a directory download), then the get routine will return an error if you try to use a FileHandle reference or a scalar reference.

-callback
is a reference to a callback function which will be called everytime a file is completed downloading. The idea of the callback function is that some recursive get's can take a very long time and the user may require some visual feedback. See CALLBACKS for an examples and how to use a callback.

The return value of get is always 1 or 0 indicating whether the entire get sequence was a success or if there was ANY failures. For instance, in a recursive get, if the server couldn't open 1 of the 10 remote files, for whatever reason, then the return value will be 0. This is so that you can have your script call the errors() routine to handle error conditions.

Previous versions of HTTP::DAV allowed the return value to be the file contents if no -to attribute was supplied. This functionality is deprecated.

Requires a working resource to be set before being called. See open.

get examples:

  $d->open("host.org/dav_dir/");

Recursively get remote my_dir/ to .

  $d->get("my_dir/",".");

Recursively get remote my_dir/ to /tmp/my_dir/ calling &mycallback($success,$mesg) everytime a file operation is completed.

  $d->get("my_dir","/tmp",\&mycallback);

Get remote my_dir/index.html to /tmp/index.html

  $d->get(-url=>"/dav_dir/my_dir/index.html",-to=>"/tmp");

Get remote index.html to /tmp/index1.html

  $d->get("index.html","/tmp/index1.html");

Get remote index.html to a filehandle

  my $fh = new FileHandle;
  $fh->open(">/tmp/index1.html");
  $d->get("index.html",\$fh);

Get remote index.html as a scalar (into the string $file_contents):

  my $file_contents;
  $d->get("index.html",\$file_contents);

Get all of the files matching the globs file1* and file2*:

  $d->get("file[12]*","/tmp");

Get all of the files matching the glob file?.html:

  $d->get("file?.html","/tmp"); # downloads file1.html and file2.html but not file3.html or file1.txt

Invalid glob:

  $d->get("/dav_dir/*/index.html","/tmp"); # Can not glob like this.
lock([URL],[OWNER],[DEPTH],[TIMEOUT],[SCOPE],[TYPE])
locks a resource. If URL is not specified, it will lock the current working resource (opened resource).
   $d->lock( -url     => "index.html",
             -owner   => "Patrick Collins",
             -depth   => "infinity",
             -scope   => "exclusive",
             -type    => "write",
             -timeout => "10h" )

See HTTP::DAV::Resource lock() for details of the above parameters.

The return value is always 1 or 0 indicating success or failure.

Requires a working resource to be set before being called. See open.

When you lock a resource, the lock is held against the current HTTP::DAV object. In fact, the locks are held in a HTTP::DAV::ResourceList object. You can operate against all of the locks that you have created as follows:

  ## Print and unlock all locks that we own.
  my $rl_obj = $d->get_lockedresourcelist();
  foreach $resource ( $rl_obj->get_resources() ) {
      @locks = $resource->get_locks(-owned=>1);
      foreach $lock ( @locks ) { 
        print $resource->get_uri . "\n";
        print $lock->as_string . "\n";
      }
      ## Unlock them?
      $resource->unlock;
  }

Typically, a simple $d->unlock($uri) will suffice.

lock example

  $d->lock($uri, -timeout=>"1d");
  ...
  $d->put("/tmp/index.html",$uri);
  $d->unlock($uri);

mkcol(URL)
make a remote collection (directory)

The return value is always 1 or 0 indicating success or failure.

Requires a working resource to be set before being called. See open.

  $d->open("host.org/dav_dir/");
  $d->mkcol("new_dir");                  # Should succeed
  $d->mkcol("/dav_dir/new_dir");         # Should succeed
  $d->mkcol("/dav_dir/new_dir/xxx/yyy"); # Should fail

move(URL,DEST,[OVERWRITE],[DEPTH])
moves one remote resource to another
-url
is the remote resource you'd like to move. Mandatory

-dest
is the remote target for the move command. Mandatory

-overwrite
optionally indicates whether the server should fail if the target exists. Valid values are ``T'' and ``F'' (1 and 0 are synonymous). Default is T.

Requires a working resource to be set before being called. See open.

The return value is always 1 or 0 indicating success or failure.

Note: if either 'URL' or 'DEST' are locked by this dav client, then the lock headers will be taken care of automatically. If either of the two URL's are locked by someone else, the server should reject the request.

move examples:

  $d->open(-url=>"host.org/dav_dir/");

move dir1/ to dir2/

  $d->move(-url=>"dir1/", -dest=>"dir2/");

non-forcefully move dir1/ to dir2/

  $d->move(-url=>"dir1/", -dest=>"dir2/",-overwrite=>0);

Move dir1/file.txt to dir2/file.txt

  $d->cwd(-url=>"dir1/");
  $d->move("file.txt","../dir2");

move file.txt to dir2/new_file.txt

  $d->move("file.txt","/dav_dir/dir2/new_file.txt")
open(URL)
opens the directory (collection resource) at URL.

open will perform a propfind against URL. If the server does not understand the request then the open will fail.

Similarly, if the server indicates that the resource at URL is NOT a collection, the open command will fail.

options([URL])
Performs an OPTIONS request against the URL or the working resource if URL is not supplied.

Requires a working resource to be set before being called. See open.

The return value is a string of comma separated OPTIONS that the server states are legal for URL or undef otherwise.

A fully compliant DAV server may offer as many methods as: OPTIONS, TRACE, GET, HEAD, DELETE, PUT, COPY, MOVE, PROPFIND, PROPPATCH, LOCK, UNLOCK

Note: IIS5 does not support PROPPATCH or LOCK on collections.

Example:

 $options = $d->options($url);
 print $options . "\n";
 if ($options=~ /\bPROPPATCH\b/) {
    print "OK to proppatch\n";
 }

Or, put more simply:

 if ( $d->options($url) =~ /\bPROPPATCH\b/ ) {
    print "OK to proppatch\n";
 }

propfind([URL],[DEPTH])
Perform a propfind against URL at DEPTH depth.

-depth can be used to specify how deep the propfind goes. ``0'' is collection only. ``1'' is collection and it's immediate members (This is the default value). ``infinity'' is the entire directory tree. Note that most DAV compliant servers deny ``infinity'' depth propfinds for security reasons.

Requires a working resource to be set before being called. See open.

The return value is an HTTP::DAV::Resource object on success or 0 on failure.

The Resource object can be used for interrogating properties or performing other operations.

 ## Print collection or content length
 if ( $r=$d->propfind( -url=>"/my_dir", -depth=>1) ) {
    if ( $r->is_collection ) {
       print "Collection\n" 
       print $r->get_resourcelist->as_string . "\n"
    } else {
       print $r->get_property("getcontentlength") ."\n";
    }
 }

Please note that although you may set a different namespace for a property of a resource during a set_prop, HTTP::DAV currently ignores all XML namespaces so you will get clashes if two properties have the same name but in different namespaces. Currently this is unavoidable but I'm working on the solution.

proppatch([URL],[NAMESPACE],PROPNAME,PROPVALUE,ACTION,[NSABBR])
If -action equals ``set'' then we set a property named -propname to -propvalue in the namespace -namespace for -url.

If -action equals ``remove'' then we unset a property named -propname in the namespace -namespace for -url.

If no action is supplied then the default action is ``set''.

The return value is an HTTP::DAV::Resource object on success or 0 on failure.

The Resource object can be used for interrogating properties or performing other operations.

To explicitly set a namespace in which to set the propname then you can use the -namespace and -nsabbr (namespace abbreviation) parameters. But you're welcome to play around with DAV namespaces.

Requires a working resource to be set before being called. See open.

It is recommended that you use set_prop and unset_prop instead of proppatch for readability.

set_prop simply calls proppatch(-action=set)> and unset_prop calls proppatch(-action=``remove'')>

See set_prop and unset_prop for examples.

put(LOCAL,[URL],[CALLBACK])
uploads the files or directories at -local to the remote destination at -url.

-local points to a file, directory or series of files or directories (indicated by a glob).

If the filename contains any of the characters `*', `?' or `[' it is a candidate for filename substitution, also known as ``globbing''. This word is then regarded as a pattern (``glob-pattern''), and replaced with an alphabetically sorted list of file names which match the pattern.

One can upload/put a string by passing a reference to a scalar in the -local parameter. See example below.

put requires a working resource to be set before being called. See open.

The return value is always 1 or 0 indicating success or failure.

See get() for a description of what the optional callback parameter does.

put examples:

Put a string to the server:

  my $myfile = "This is the contents of a file to be uploaded\n";
  $d->put(-local=>\$myfile,-url=>"http://www.host.org/dav_dir/file.txt";);

Put a local file to the server:

  $d->put(-local=>"/tmp/index.html,-url=>"http://www.host.org/dav_dir/";);

Put a series of local files to the server:

  In these examples, /tmp contains file1.html, file1, file2.html, 
  file2.txt, file3.html, file2/
  $d->put(-local=>"/tmp/file[12]*",-url=>"http://www.host.org/dav_dir/";);

  uploads file1.html, file1, file2.html, file2.txt and the directory file2/ to dav_dir/.

set_prop([URL],[NAMESPACE],PROPNAME,PROPVALUE)
Sets a property named -propname to -propvalue in the namespace -namespace for -url.

Requires a working resource to be set before being called. See open.

The return value is an HTTP::DAV::Resource object on success or 0 on failure.

The Resource object can be used for interrogating properties or performing other operations.

Example:

 if ( $r = $d->set_prop(-url=>$url,
              -namespace=>"dave",
              -propname=>"author",
              -propvalue=>"Patrick Collins"
             ) ) {
    print "Author property set\n";
 } else {
    print "set_prop failed:" . $d->message . "\n";
 }

See the note in propfind about namespace support in HTTP::DAV. They're settable, but not readable.

steal([URL])
forcefully steals any locks held against URL.

steal will perform a propfind against URL and then, any locks that are found will be unlocked one by one regardless of whether we own them or not.

Requires a working resource to be set before being called. See open.

The return value is always 1 or 0 indicating success or failure. If multiple locks are found and unlocking one of them fails then the operation will be aborted.

 if ($d->steal()) {
    print "Steal succeeded\n";
 } else {
    print "Steal failed: ". $d->message() . "\n";
 }

unlock([URL])
unlocks any of our locks on URL.

Requires a working resource to be set before being called. See open.

The return value is always 1 or 0 indicating success or failure.

 if ($d->unlock()) {
    print "Unlock succeeded\n";
 } else {
    print "Unlock failed: ". $d->message() . "\n";
 }

unset_prop([URL],[NAMESPACE],PROPNAME)
Unsets a property named -propname in the namespace -namespace for -url. Requires a working resource to be set before being called. See open.

The return value is an HTTP::DAV::Resource object on success or 0 on failure.

The Resource object can be used for interrogating properties or performing other operations.

Example:

 if ( $r = $d->unset_prop(-url=>$url,
              -namespace=>"dave",
              -propname=>"author",
             ) ) {
    print "Author property was unset\n";
 } else {
    print "set_prop failed:" . $d->message . "\n";
 }

See the note in propfind about namespace support in HTTP::DAV. They're settable, but not readable.

ACCESSOR METHODS

get_user_agent
Returns the clients' working HTTP::DAV::UserAgent object.

You may want to interact with the HTTP::DAV::UserAgent object to modify request headers or provide advanced authentication procedures. See dave for an advanced authentication procedure.

get_last_request
Takes no arguments and returns the clients' last outgoing HTTP::Request object.

You would only use this to inspect a request that has already occurred.

If you would like to modify the HTTP::Request BEFORE the HTTP request takes place (for instance to add another header), you will need to get the HTTP::DAV::UserAgent using get_user_agent and interact with that.

get_workingresource
Returns the currently ``opened'' or ``working'' resource (HTTP::DAV::Resource).

The working resource is changed whenever you open a url or use the cwd command.

e.g. $r = $d->get_workingresource print ``pwd: '' . $r->get_uri . ``\n'';

get_workingurl
Returns the currently ``opened'' or ``working'' URL.

The working resource is changed whenever you open a url or use the cwd command.

  print "pwd: " . $d->get_workingurl . "\n";

get_lockedresourcelist
Returns an HTTP::DAV::ResourceList object that represents all of the locks we've created using THIS dav client.
  print "pwd: " . $d->get_workingurl . "\n";

get_absolute_uri(REL_URI,[BASE_URI])
This is a useful utility function which joins BASE_URI and REL_URI and returns a new URI.

If BASE_URI is not supplied then the current working resource (as indicated by get_workingurl) is used. If BASE_URI is not set and there is no current working resource the REL_URI will be returned.

For instance: $d->open(``http://host.org/webdav/dir1/'');

 # Returns "http://host.org/webdav/dir2/";
 $d->get_absolute_uri(-rel_uri=>"../dir2");
 # Returns "http://x.org/dav/dir2/file.txt";
 $d->get_absolute_uri(-rel_uri  =>"dir2/file.txt",
                      ->base_uri=>"http://x.org/dav/";);

Note that it subtly takes care of trailing slashes.

ERROR HANDLING METHODS

message
message gets the last success or error message.

The return value is always a scalar (string) and will change everytime a dav operation is invoked (lock, cwd, put, etc).

See also errors for operations which contain multiple error messages.

errors
Returns an @array of error messages that had been set during a multi-request operation.

Some of HTTP::DAV's operations perform multiple request to the server. At the time of writing only put and get are considered multi-request since they can operate recursively requiring many HTTP requests.

In these situations you should check the errors array if to determine if any of the requests failed.

The errors function is used for multi-request operations and not to be confused with a multi-status server response. A multi-status server response is when the server responds with multiple error messages for a SINGLE request. To deal with multi-status responses, see HTTP::DAV::Response.

 # Recursive put
 if (!$d->put( "/tmp/my_dir", $url ) ) {
    # Get the overall message
    print $d->message;
    # Get the individual messages
    foreach $err ( $d->errors ) { print "  Error:$err\n" }
 }

is_success
Returns the status of the last DAV operation performed through the HTTP::DAV interface.

This value will always be the same as the value returned from an HTTP::DAV::method. For instance:

  # This will always evaluate to true
  ($d->lock($url) eq $d->is_success) ?

You may want to use the is_success method if you didn't capture the return value immediately. But in most circumstances you're better off just evaluating as follows: if($d->lock($url)) { ... }

get_lastresponse
Takes no arguments and returns the last seen HTTP::DAV::Response object.

You may want to use this if you have just called a propfind and need the individual error messages returned in a MultiStatus.

If you find that you're using get_last_response() method a lot, you may be better off using the more advanced HTTP::DAV interface and interacting with the HTTP::DAV::* interfaces directly as discussed in the intro. For instance, if you find that you're always wanting a detailed understanding of the server's response headers or messages, then you're probably better off using the HTTP::DAV::Resource methods and interpreting the HTTP::DAV::Response directly.

To perform detailed analysis of the server's response (if for instance you got back a multistatus response) you can call get_lastresponse which will return to you the most recent response object (always the result of the last operation, PUT, PROPFIND, etc). With the returned HTTP::DAV::Response object you can handle multi-status responses.

For example:

   # Print all of the messages in a multistatus response
   if (! $d->unlock($url) ) {
      $response = $d->get_lastresponse();
      if ($response->is_multistatus() ) {
        foreach $num ( 0 .. $response->response_count() ) {
           ($err_code,$mesg,$url,$desc) =
              $response->response_bynum($num);
           print "$mesg ($err_code) for $url\n";
        }
      }
   }

ADVANCED METHODS

new_resource
Creates a new resource object with which to play. This is the preferred way of creating an HTTP::DAV::Resource object if required. Why? Because each Resource object needs to sit within a global HTTP::DAV client. Also, because the new_resource routine checks the HTTP::DAV locked resource list before creating a new object.
 $dav->new_resource( -uri => "http://..."; );

set_workingresource(URL)
Sets the current working resource to URL.

You shouldn't need this method. Call open or cwd to set the working resource.

You CAN call set_workingresource but you will need to perform a propfind immediately following it to ensure that the working resource is valid.


INSTALLATION, TODO, MAILING LISTS and REVISION HISTORY

Please see the primary HTTP::DAV webpage at (http://www.webdav.org/perldav/http-dav/) or the README file in this library.


SEE ALSO

You'll want to also read: HTTP::DAV::Response, HTTP::DAV::Resource, dave

and maybe if you're more inquisitive: LWP::UserAgent,HTTP::Request, HTTP::DAV::Comms,HTTP::DAV::Lock, HTTP::DAV::ResourceList, HTTP::DAV::Utils


AUTHOR AND COPYRIGHT

This module is Copyright (C) 2001 by

    Patrick Collins
    G03 Gloucester Place, Kensington
    Sydney, Australia
    Email: pcollins@cpan.org
    Phone: +61 2 9663 4916

All rights reserved.

You may distribute this module under the terms of either the GNU General Public License or the Artistic License, as specified in the Perl README file.

 HTTP::DAV - A WebDAV client library for Perl5