= The Tahoe CLI commands = Tahoe provides a single executable named "tahoe", which can be used to create and manage client/server nodes, manipulate the virtual drive, and perform several debugging/maintenance tasks. This executable lives in the source tree at "bin/tahoe". Once you've done a build (by running "make"), bin/tahoe can be run in-place: if it discovers that it is being run from within a Tahoe source tree, it will modify sys.path as necessary to use all the source code and dependent libraries contained in that tree. If you've installed Tahoe (using "make install", or by installing a binary package), then the tahoe executable will be available somewhere else, perhaps in /usr/bin/tahoe . In this case, it will use your platform's normal PYTHONPATH search paths to find the tahoe code and other libraries. == CLI Command Overview == The "tahoe" tool provides access to three categories of commands. * node management: create a client/server node, start/stop/restart it * vdrive manipulation: list files, upload, download, delete, rename * debugging: unpack cap-strings, examine share files To get a list of all commands, just run "tahoe" with no additional arguments. "tahoe --help" might also provide something useful. Running "tahoe --version" will display a list of version strings, starting with the "allmydata" module (which contains the majority of the Tahoe functionality) and including versions for a number of dependent libraries, like Twisted, Foolscap, pycryptopp, and zfec. == Node Management == "tahoe create-client [NODEDIR]" is the basic make-a-new-node command. It creates a new directory and populates it with files that will allow the "tahoe start" command to use it later on. This command creates nodes that have client functionality (upload/download files), web API services (controlled by the 'webport' file), and storage services (controlled by "no_storage" and the like). NODEDIR defaults to ~/.tahoe/ , and newly-created clients default to publishing a web server on port 8123 (limited to the loopback interface, at 127.0.0.1, to restrict access to other programs on the same host). All of the other "tahoe" subcommands use corresponding defaults. "tahoe create-introducer [NODEDIR]" is used to create the Introducer node. This node provides introduction services and nothing else. When started, this node will produce an introducer.furl, which should be published to all clients. "tahoe create-key-generator [NODEDIR]" is used to create a special "key-generation" service, which allows a client to offload their RSA key generation to a separate process. Since RSA key generation takes several seconds, and must be done each time a directory is created, moving it to a separate process allows the first process (perhaps a busy webapi server) to continue servicing other requests. The key generator exports a FURL that can be copied into a client node to enable this functionality. "tahoe start [NODEDIR]" will launch a previously-created node. It will launch the node into the background, using the standard Twisted "twistd" daemon-launching tool. "tahoe run [NODEDIR]" will start a previous-created node in the foreground. Some platforms are unable to run a daemon in the background: this command provides a way to use a tahoe node on such platforms. "tahoe stop [NODEDIR]" will shut down a running node. "tahoe restart [NODEDIR]" will stop and then restart a running node. This is most often used by developers who have just modified the code and want to start using their changes. == Virtual Drive Manipulation == These commands let you exmaine a Tahoe virtual drive, providing basic list/upload/download/delete/rename/mkdir functionality. They can be used as primitives by other scripts. Most of these commands are fairly thin wrappers around webapi calls. By default, all vdrive-manipulation commands look in ~/.tahoe/ to figure out which Tahoe node they should use. When the CLI command uses webapi calls, it will use ~/.tahoe/node.url for this purpose: a running Tahoe node that provides a webapi port will write its URL into this file. If you want to use a node on some other host, just create ~/.tahoe/ and copy that node's webapi URL into this file, and the CLI commands will contact that node instead of a local one. These commands also use a table of "aliases" to figure out which directory they ought to use a starting point. This is explained in more detail below. === Starting Directories === As described in architecture.txt, the Tahoe distributed filesystem consists of a collection of directories and files, each of which has a "read-cap" or a "write-cap" (also known as a URI). Each directory is simply a table that maps a name to a child file or directory, and this table is turned into a string and stored in a mutable file. The whole set of directory and file "nodes" are connected together into a directed graph. To use this collection of files and directories, you need to choose a starting point: some specific directory that we will refer to as a "starting directory". For a given starting directory, the "ls [STARTING_DIR]:" command would list the contents of this directory, the "ls [STARTING_DIR]:dir1" command would look inside this directory for a child named "dir1" and list its contents, "ls [STARTING_DIR]:dir1/subdir2" would look two levels deep, etc. Note that there is no real global "root" directory, but instead each starting directory provides a different, possibly overlapping perspective on the graph of files and directories. Each tahoe node remembers a list of starting points, named "aliases", in a file named ~/.tahoe/private/aliases . These aliases are short strings that stand in for a directory read- or write- cap. If you use the command line "ls" without any "[STARTING_DIR]:" argument, then it will use the default alias, which is "tahoe", therefore "tahoe ls" has the same effect as "tahoe ls tahoe:". The same goes for the other commands which can reasonably use a default alias: get, put, mkdir, mv, and rm. For backwards compatibility with Tahoe-1.0, if the "tahoe": alias is not found in ~/.tahoe/private/aliases, the CLI will use the contents of ~/.tahoe/private/root_dir.cap instead. Tahoe-1.0 had only a single starting point, and stored it in this root_dir.cap file, so Tahoe-1.1 will use it if necessary. However, once you've set a "tahoe:" alias with "tahoe set-alias", that will override anything in the old root_dir.cap file. The Tahoe CLI commands use the same filename syntax as scp and rsync -- an optional "alias:" prefix, followed by the pathname or filename. Some commands (like "tahoe cp") use the lack of an alias to mean that you want to refer to a local file, instead of something from the tahoe virtual filesystem. [TODO] Another way to indicate this is to start the pathname with a dot, slash, or tilde. When you're dealing a single starting directory, the "tahoe:" alias is all you need. But when you want to refer to something that isn't yet attached to the graph rooted at that starting directory, you need to refer to it by its capability. The way to do that is either to use its capability directory as an argument on the command line, or to add an alias to it, with the "tahoe add-alias" command. Once you've added an alias, you can use that alias as an argument to commands. The best way to get started with Tahoe is to create a node, start it, then use the following command to create a new directory and set it as your "tahoe:" alias: tahoe add-alias tahoe `tahoe mkdir` After that you can use "tahoe ls tahoe:" and "tahoe cp local.txt tahoe:", and both will refer to the directory that you've just created. ==== SECURITY NOTE: For users of shared systems ==== Remember that command-line arguments are visible to other users (through the 'ps' command, or the windows Process Explorer tool), so if you are using a tahoe node on a shared host, your login neighbors will be able to see (and capture) any directory caps that you set up with the "tahoe add-alias" command. To avoid this, bypass add-alias and edit the NODEDIR/private/aliases file directly, by adding a line like this: fun: URI:DIR2:ovjy4yhylqlfoqg2vcze36dhde:4d4f47qko2xm5g7osgo2yyidi5m4muyo2vjjy53q4vjju2u55mfa By entering the dircap through the editor, the command-line arguments are bypassed, and other users will not be able to see them. Once you've added the alias, no other secrets are passed through the command line, so this vulnerability becomes less significant: they can still see your filenames and other arguments you type there, but not the caps that Tahoe uses to permit access to your files and directories. === Command Syntax Summary === tahoe add-alias alias cap tahoe list-aliases tahoe mkdir tahoe mkdir [alias:]path tahoe ls [alias:][path] tahoe webopen [alias:]path tahoe put [--mutable] [localfrom:-] tahoe put [--mutable] [localfrom:-] [alias:]to tahoe put [--mutable] [localfrom:-] [alias:]subdir/to tahoe put [--mutable] [localfrom:-] dircap:to tahoe put [--mutable] [localfrom:-] dircap:./subdir/to tahoe put [localfrom:-] mutable-file-writecap tahoe get [alias:]from [localto:-] tahoe cp [-r] [alias:]frompath [alias:]topath tahoe rm [alias:]what tahoe mv [alias:]from [alias:]to tahoe ln [alias:]from [alias:]to === Command Examples === tahoe mkdir This creates a new empty unlinked directory, and prints its write-cap to stdout. The new directory is not attached to anything else. tahoe add-alias fun DIRCAP An example would be: tahoe add-alias fun URI:DIR2:ovjy4yhylqlfoqg2vcze36dhde:4d4f47qko2xm5g7osgo2yyidi5m4muyo2vjjy53q4vjju2u55mfa This creates an alias "fun:" and configures it to use the given directory cap. Once this is done, "tahoe ls fun:" will list the contents of this directory. Use "tahoe add-alias tahoe DIRCAP" to set the contents of the default "tahoe:" alias. tahoe create-alias fun This combines 'tahoe mkdir' and 'tahoe add-alias' into a single step. tahoe list-aliases This displays a table of all configured aliases. tahoe mkdir subdir tahoe mkdir /subdir This both create a new empty directory and attaches it to your root with the name "subdir". tahoe ls tahoe ls / tahoe ls tahoe: tahoe ls tahoe:/ All four list the root directory of your personal virtual filesystem. tahoe ls subdir This lists a subdirectory of your filesystem. tahoe webopen tahoe: tahoe webopen tahoe:subdir/ This uses the python 'webbrowser' module to cause a local web browser to open to the web page for the given directory. This page offers interfaces to add, dowlonad, rename, and delete files in the directory. tahoe put file.txt tahoe put ./file.txt tahoe put /tmp/file.txt tahoe put ~/file.txt These upload the local file into the grid, and prints the new read-cap to stdout. The uploaded file is not attached to any directory. All one-argument forms of "tahoe put" perform an unlinked upload. tahoe put - tahoe put These also perform an unlinked upload, but the data to be uploaded is taken from stdin. tahoe put file.txt uploaded.txt tahoe put file.txt tahoe:uploaded.txt These upload the local file and add it to your root with the name "uploaded.txt" tahoe put file.txt subdir/foo.txt tahoe put - subdir/foo.txt tahoe put file.txt tahoe:subdir/foo.txt tahoe put file.txt DIRCAP:./foo.txt tahoe put file.txt DIRCAP:./subdir/foo.txt These upload the named file and attach them to a subdirectory of the given root directory, under the name "foo.txt". Note that to use a directory write-cap instead of an alias, you must use ":./" as a separator, rather than ":", to help the CLI parser figure out where the dircap ends. When the source file is named "-", the contents are taken from stdin. tahoe put file.txt --mutable Create a new mutable file, fill it with the contents of file.txt, and print the new write-cap to stdout. tahoe put file.txt MUTABLE-FILE-WRITECAP Replace the contents of the given mutable file with the contents of file.txt and prints the same write-cap to stdout. tahoe cp file.txt tahoe:uploaded.txt tahoe cp file.txt tahoe: tahoe cp file.txt tahoe:/ tahoe cp ./file.txt tahoe: These upload the local file and add it to your root with the name "uploaded.txt". tahoe cp tahoe:uploaded.txt downloaded.txt tahoe cp tahoe:uploaded.txt ./downloaded.txt tahoe cp tahoe:uploaded.txt /tmp/downloaded.txt tahoe cp tahoe:uploaded.txt ~/downloaded.txt This downloads the named file from your tahoe root, and puts the result on your local filesystem. tahoe cp tahoe:uploaded.txt fun:stuff.txt This copies a file from your tahoe root to a different virtual directory, set up earlier with "tahoe add-alias fun DIRCAP". tahoe rm uploaded.txt tahoe rm tahoe:uploaded.txt This deletes a file from your tahoe root. tahoe mv uploaded.txt renamed.txt tahoe mv tahoe:uploaded.txt tahoe:renamed.txt These rename a file within your tahoe root directory. tahoe mv uploaded.txt fun: tahoe mv tahoe:uploaded.txt fun: tahoe mv tahoe:uploaded.txt fun:uploaded.txt These move a file from your tahoe root directory to the virtual directory set up earlier with "tahoe add-alias fun DIRCAP" == Debugging == For a list of all debugging commands, use "tahoe debug". "tahoe debug find-shares STORAGEINDEX NODEDIRS.." will look through one or more storage nodes for the share files that are providing storage for the given storage index. "tahoe debug catalog-shares NODEDIRS.." will look through one or more storage nodes and locate every single share they contain. It produces a report on stdout with one line per share, describing what kind of share it is, the storage index, the size of the file is used for, etc. It may be useful to concatenate these reports from all storage hosts and use it to look for anomalies. "tahoe debug dump-share SHAREFILE" will take the name of a single share file (as found by "tahoe find-shares") and print a summary of its contents to stdout. This includes a list of leases, summaries of the hash tree, and information from the UEB (URI Extension Block). For mutable file shares, it will describe which version (seqnum and root-hash) is being stored in this share. "tahoe debug dump-cap CAP" will take a URI (a file read-cap, or a directory read- or write- cap) and unpack it into separate pieces. The most useful aspect of this command is to reveal the storage index for any given URI. This can be used to locate the share files that are holding the encoded+encrypted data for this file. "tahoe debug repl" will launch an interactive python interpreter in which the Tahoe packages and modules are available on sys.path (e.g. by using 'import allmydata'). This is most useful from a source tree: it simply sets the PYTHONPATH correctly and runs the 'python' executable. "tahoe debug corrupt-share SHAREFILE" will flip a bit in the given sharefile. This can be used to test the client-side verification/repair code. Obviously this command should not be used during normal operation.