--- /dev/null
+
+Writing "8011" into CLIENTDIR/webport causes the client to run a webserver on
+port 8011. Writing "tcp:8011:interface=127.0.0.1" into CLIENTDIR/webport does
+the same but binds to the loopback interface, insuring that only the programs
+on the local host can connect. Using
+"ssl:8011:privateKey=mykey.pem:certKey=cert.pem" would run an SSL server. See
+twisted.application.strports for more details.
+
+If CLIENTDIR/webpassword exists, it will be used (somehow) to require HTTP
+Digest Authentication for all webserver connections.
+
+
+The client provides some small number of "virtual drives". In the 0.4.0
+release, this number is two: the first is the global shared vdrive, the
+second is the private non-shared vdrive. We will call these "global" and
+"private" for now.
+
+For the purpose of this document, let us assume that the vdrives currently
+contain the following directories and files:
+
+ global/
+ global/Documents/
+ global/Documents/notes.txt
+
+ private/
+ private/Pictures/
+ private/Pictures/tractors.jpg
+
+
+== vdrive ==
+
+Within the webserver, there is a tree of resources. The top-level "vdrive"
+resource gives access to files and directories in all of the user's virtual
+drives. For example, the URL that corresponds to notes.txt would be:
+
+FILEURL = http://localhost:8011/vdrive/global/Documents/notes.txt
+
+and the URL for tractors.jpg would be:
+
+ http://localhost:8011/vdrive/private/Pictures/tractors.jpg
+
+In addition, each directory has a corresponding URL. The Pictures URL is:
+
+DIRURL = http://localhost:8011/vdrive/private/Pictures
+
+Now, what can we do with these URLs? By varying the HTTP "method"
+(GET/PUT/POST/DELETE) and by appending a type-indicating query argument, we
+control how what we want to do with the data and how it should be presented.
+
+In the following examples, FILEURL and DIRURL are abbreviations for the
+previously listed examples. In addition. NEWFILEURL and NEWDIRURL are URLs
+for files and directories which do not yet exist.
+
+=== Files ===
+
+ GET FILEURL
+
+ This simply retrives the contents of the file at the given place in the
+ vdrive. The Content-Type is set according to the vdrive's metadata (if
+ available) or by using the usual filename-extension-magic built into most
+ webservers. The file's contents are provided in the body of the HTTP
+ response.
+
+ (thought: we could conceivably provide some measure of gathering-peers
+ progress and pre-plaintext status information by emitting some extra
+ X-Tahoe-Status headers. Of course, once the headers are done and we start
+ sending plaintext, we have to stop sending such headers)
+
+ PUT NEWFILEURL
+
+ This uploads a file to the given place in the vdrive. It will create
+ intermediate directory nodes as necessary. The file's contents are taken
+ from the body of the HTTP request. For convenience, the HTTP response
+ contains the URI that results from uploading the file, although the client
+ is not obligated to do anything with the URI. According to the HTTP/1.1
+ specification (rfc2068), this should return a 200 (OK) code when modifying
+ and existing file, and a 201 (Created) code when creating a new file.
+
+ DELETE FILEURL
+
+ This deletes the given file from the vdrive. Note that this *does not*
+ delete any parent directories, so a sequence of 'PUT NEWFILEURL' and
+ 'DELETE NEWFILEURL' does not return the vdrive to its original state (it
+ may leave some intermediate directory nodes).
+
+ GET FILEURL?t=json
+ GET FILEURL?t=xml
+
+ This returns machine-parseable information about the file in the HTTP
+ response body, including file size, metadata (like Content-Type), and URIs.
+ This information is also required to contain a flag that distinguishes
+ between files and directories. Programatic clients are expected to use this
+ query before actually downloading the file's contents.
+
+ GET FILEURL?localfile=$FILENAME
+
+ This instructs the client to download the given file and write its contents
+ into the local filesystem at $FILENAME. This request will only be accepted
+ from an HTTP client connection originating at 127.0.0.1 . This request is
+ most useful when the client node and the HTTP client are operated by the
+ same user. $FILENAME should be an absolute pathname.
+
+ (thoughts: we could use either the response headers or the response body
+ to indicate download progress)
+
+ PUT NEWFILEURL?localfile=$FILENAME
+
+ This uploads file to the vdrive and gets the contents from a file in the
+ client's local filesystem. As with GET, this request will only be accepted
+ from an HTTP connection originating from 127.0.0.1.
+
+ (we could indicate upload progress too. The response body could contain
+ the URI of the uploaded file)
+
+
+ GET FILEURL?t=uri
+
+ This returns the URI of the given file in the HTTP response body.
+
+=== Directories ===
+
+ GET DIRURL
+
+ This returns an HTML page, intended to be used by humans, which contains
+ HREF links to all files and directories reachable from this dirnode. These
+ HREF links do not have a t= argument, meaning that a human who follows them
+ will get pages also meant for a human. It also contains forms to upload new
+ files, and to delete files and directories. These forms use POST methods to
+ do their job.
+
+ GET DIRURL?t=json
+ GET DIRURL?t=xml
+
+ This returns machine-parseable information about this directory in the HTTP
+ response body. This information first contains a flag to indicate that
+ DIRURL referenced a directory (as opposed to a file). Then it contains a
+ flag to indicate whether this is a read-write dirnode or a read-only
+ dirnode. Finally it also contains information about the children of this
+ directory, probably as a mapping from child name to a set of metadata about
+ the child (basically the same data that would appear in a corresponding
+ GET?t=xml of the child itself). A programmatic client should be able to use
+ the information from this query to display filesystem navigation choices to
+ a human user.
+
+ GET DIRURL?t=uri
+ GET DIRURL?t=readonly-uri
+
+ Return a URI for this dirnode in the HTTP response body. If the dirnode is
+ read-only, the t=uri and t=readonly-uri responses will be the same.
+
+ PUT NEWDIRURL?t=mkdir
+
+ Create a new empty directory at the given path. The HTTP response contains
+ the URI of the given directory, although the client is not obligated to do
+ anything with it.
+
+ GET DIRURL?localdir=$DIRNAME
+
+ This instructs the client to perform a recursive download of the given
+ directory and all its descendant files and directories, writing the results
+ to the local filesystem starting at DIRNAME.
+
+ (thoughts: we could use the response headers or the response body to
+ indicate download progress)
+
+ PUT NEWDIRURL?localdir=$DIRNAME
+
+ This instructs the client to perform a recursive upload of a directory on
+ the local filesystem into the vdrive at the given location.
+
+
+== POST Forms ==
+
+ POST DIRURL?t=upload-form
+
+ This instructs the client to upload a file into the given dirnode. We need
+ this because forms are the only way for a web browser to upload a file
+ (browsers do not know how to do PUT or DELETE). The file's contents and the
+ new child name will be included in the form's arguments. This can only be
+ used to upload a single file at a time.
+
+ POST DIRURL?t=mkdir-form
+
+ This instructs the client to create a new empty directory. The name of the
+ new child directory will be included in the form's arguments.
+
+ POST DIRURL?t=put-uri-form
+
+ This instructs the client to attach a child that is referenced by URI (just
+ like the PUT NEWFILEURL?t=uri method). The name and URI of the new child
+ will be included in the form's arguments.
+
+ POST DIRURL?t=delete-form
+
+ This instructs the client to delete a file from the given dirnode. The name
+ of the child to be deleted will be included in the form's arguments.
+
+
+== URI ==
+
+ http://localhost:8011/uri/$URI
+
+ A separate top-level resource namespace ("uri" instead of "vdrive") is used
+ to get access to files and dirnodes that are indexed directly by URI,
+ rather than by going through the vdrive. The resource thus referenced is
+ used the same way as if it were accessed through the vdrive, including
+ child-resource-traversal behavior. For example, if the URI corresponds to a
+ file, then
+
+ GET http://localhost:8011/uri/$URI
+
+ would retrieve the contents of the file. If the URI corresponds to a
+ directory, then:
+
+ PUT http://localhost:8011/uri/$URI/subdir/newfile?localfile=$FILENAME
+
+ would upload a file (with contents taken from the local filesystem) to a
+ new file in a subdirectory of the referenced dirnode.
+
+ PUT NEWFILEURL?t=uri
+
+ This attaches a child (either a file or a directory) to the vdrive at the
+ given location. The URI is provided in the body of the HTTP request. This
+ can be used to attach a shared directory to the vdrive. Intermediate
+ directories are created on-demand just like with the regular PUT command.
+
+== XMLRPC ==
+
+ http://localhost:8011/xmlrpc
+
+ This resource provides an XMLRPC server on which all of the previous
+ operations can be expressed as function calls taking a "pathname" argument.
+ This is provided for applications that want to think of everything in terms
+ of XMLRPC.
+
+ listdir(vdrivename, path) -> dict of (childname -> (stuff))
+ put(vdrivename, path, contents) -> URI
+ get(vdrivename, path) -> contents
+ mkdir(vdrivename, path) -> URI
+ put_localfile(vdrivename, path, localfilename) -> URI
+ get_localfile(vdrivename, path, localfilename)
+ put_localdir(vdrivename, path, localdirname) # recursive
+ get_localdir(vdrivename, path, localdirname) # recursive
+ put_uri(vdrivename, path, URI)
+
+ etc..