Getting started

This guide will walk you through the steps of synchronizing your first files over brig. You will learn about the concepts behind it along the way. Everything is hands on, so make sure to open a terminal. For now, brig has no other user interface.

Precursor: The help system

brig has some built-in helpers to serve as support for your memory. Before you dive into the actual commands, you should learn how to get help.

Built-in documentation

Every command offers detailed built-in help, which you can view using the brig help command:

$ brig help stage
NAME:
   brig stage - Add a local file to the storage

USAGE:
   brig stage [command options] (<local-path> [<path>]|--stdin <path>)

CATEGORY:
   WORKING TREE COMMANDS

DESCRIPTION:
   Read a local file (given by »local-path«) and try to read
   it. This is the conceptual equivalent of »git add«. [...]

EXAMPLES:

   $ brig stage file.png                         # gets added as /file.png
   $ brig stage file.png /photos/me.png          # gets added as /photos/me.png
   $ cat file.png | brig stage --stdin /file.png # gets added as /file.png

OPTIONS:
   --stdin, -i  Read data from stdin

Shell autocompletion

If you don’t like to remember the exact name of each command, you can use the provided autocompletion. For this to work you have to insert this at the end of your .bashrc:

source $GOPATH/src/github.com/sahib/brig/autocomplete/bash_autocomplete

Or if you happen to use zsh, append this to your .zshrc:

source $GOPATH/src/github.com/sahib/brig/autocomplete/zsh_autocomplete

After starting a new shell you should be able to autocomplete most commands. Try this for example by typing brig remote <tab>.

Open the online documentation

By typing brig docs you’ll get a tab opened in your browser with this domain loaded.

Reporting bugs

If you need to report a bug you can use a built-in utility to do that. It will gather all relevant information, create a report and open a tab with the GitHub issue tracker in a browser for you. Only thing left for you is to fill out some questions in the report and include anything you think is relevant.

$ brig bug

To actually create the issue you sadly need an GitHub account.

Creating a repository

Let’s get started with the actual working commands.

You need a central place where brig stores files you give it. This place is called a »repository« or short »repo«. Think of it as a database where all files (and some metadata about them) is copied to. It is important to keep in mind that brig copies the file and does not do anything destructive to the original file.

By creating a new repository you also generate your identity, under which your buddies can later find and authenticate you.

But enough of the mere theory, let’s get started:

# Create a place where we store our metadata.
$ mkdir ~/sync
$ brig --repo ~/sync init ali@woods.org/desktop
27.12.2017/14:44:39 ⚐ Starting daemon from: /home/sahib/go/bin/brig
⚠  39 New passphrase:

Well done! Please re-type your password now:
⚠  39 Retype passphrase:

       _____         /  /\        ___          /  /\
      /  /::\       /  /::\      /  /\        /  /:/_
     /  /:/\:\     /  /:/\:\    /  /:/       /  /:/ /\
    /  /:/~/::\   /  /:/~/:/   /__/::\      /  /:/_/::\
   /__/:/ /:/\:| /__/:/ /:/___ \__\/\:\__  /__/:/__\/\:\
   \  \:\/:/~/:/ \  \:\/:::::/    \  \:\/\ \  \:\ /~~/:/
    \  \::/ /:/   \  \::/~~~~      \__\::/  \  \:\  /:/
     \  \:\/:/     \  \:\          /__/:/    \  \:\/:/
      \  \::/       \  \:\         \__\/      \  \::/
       \__\/         \__\/                     \__\/


     A new file README.md was automatically added.
     Use 'brig cat README.md' to view it & get started.
$ cd ~/sync
$ ls
config.yml  data  gpg.prv  gpg.pub  logs  metadata
meta.yml  passwd.locked  remotes.yml

The name you specified after the init is the name that will be shown to other users and by which you are searchable in the network. See Choosing and finding names for more details on the subject.

Once the init ran successfully there will be a daemon process running the background. Every other brig commands will communicate with it via a local network socket.

Also note that a lot of files were created in the current directory. This is all part of the metadata that is being used by the daemon that runs in the background. Please try not to modify them.

Passwords

You will be asked to enter a new password. The more secure the password is you entered, the greener the prompt gets [1]. This password is used to store the metadata in an encrypted manner on your filesystem and without further configuration it needs to be re-entered every time you start the daemon. There are two ways to prevent that:

  1. Use a password helper and tell brig how to get a password from it by using -w / --password-helper on the init command. We recommend using pass to do that:

    # Generate a password and store it in "pass":
    $ pass generate brig/ali -n 20
    # Tell brig how to get the password out of "pass":
    # (This is an alternative to the way shown above,
    #  if you try it out we first need to shut down the previous daemon)
    $ brig daemon quit
    $ brig --repo ~/sync-with-password init -w "pass brig/ali" ali@woods.org/desktop
    # Now pass will ask you for the master password with
    # a nice dialog whenever one if its passwords is first used.
    

    If you like this setup for an existing repo, take a look at the Configuration section.

  2. Do not use a password. You can do this by passing -x to the init command. This is obviously not recommended.

Note

Using a good password is especially important if you’re planning to move the repo, i.e. carrying it around you on a usb stick. When the daemon shuts down it locks and encrypts all files in the repository (including all metadata and keys), so nobodoy is able to access them anymore.

Adding & Viewing files

Now let’s add some files to brig. We do this by using brig stage. It’s called stage because all files first get added to a staging area. If you want, and are able to remember that easier, you can also use brig add.

$ echo "Hello World" > /tmp/hello.world
$ brig stage /tmp/hello.world
$ brig cat hello.world
Hello World
$ brig ls
SIZE   MODTIME          PATH          PIN
443 B  Dec 27 14:44:44  /README.md     🖈
12 B   Dec 27 15:14:16  /hello.world   🖈

This adds the content of /tmp/hello.world to a new file in brig called /hello.world. The name was automatically chosen from looking at the base name of the added file. All files in brig have their own name, possibly differing from the content of the file they originally came from. Of course, you can also add whole directories.

If you want to use a different name, you can simply pass the new name as second argument to stage:

$ brig stage /tmp/hello.world /hallo.welt

You also previously saw brig cat which can be used to get the content of a file again. brig ls in contrast shows you a list of currently existing files, including their size, last modification time, path and pin state [2].

One useful feature of brig cat is that you can output directories as well. When specifying a directory as path, a .tar archive is being outputted. You can use that easily to store whole directories on your disk or archive in order to send it to some client for example:

# Create a tar from root and unpack it to the current directory.
$ brig cat | tar xfv -
# Create .tar.gz out of of the /photos directory.
$ brig cat photos | gzip -f > photos.tar.gz

Coreutils

You probably already noticed that a lot of commands you’d type in a terminal on a normal day have a sibling as brig command. Here is a short overview of the available commands:

$ brig mkdir photos
$ brig touch photos/me.png
$ brig tree
    • 🖈
├──photos 🖈
│  └── me.png 🖈
├── README.md 🖈
└── hello.world 🖈

2 directories, 2 files
$ brig cp photos/me.png photos/moi.png
$ brig mv photos/me.png photos/ich.png
# NOTE: There is no "-r" switch. Directories are always deleted recursively.
$ brig rm photos

Please refer to brig help <command> for more information about those. Sometimes they work a little bit different [3] and a bit less surprising than their counterparts. Also note that there is no brig cd currently. All paths must be absolute.

Mounting repositories

Using those specialized brig commands might not feel very seamless, especially when being used to tools like file browsers. And indeed, those commands are only supposed to serve as a low-level way of interacting with brig and as means for scripting own workflows.

For your daily workflow it is far easier to mount all files known to brig to a directory of your choice and use it with your normal tools. To accomplish that brig supports a FUSE filesystem that can be controlled via the mount and fstab commands. Let’s look at brig mount:

$ mkdir ~/data
$ brig mount ~/data
$ cd ~/data
$ cat hello-world
Hello World
$ echo 'Salut le monde!' > salut-monde.txt
# There is no difference between brig's "virtual view"
# and the contents of the mount:
$ brig cat salut-monde.txt
Salut le monde!

You can use this directory exactly [4] like a normal one. You can have any number of mounts. This proves especially useful when only mounting a subdirectory of brig (let’s say Public) with the --root option of brig mount and mounting all other files as read only (--readonly).

$ brig mount ~/data --readonly
$ brig mkdir /writable
$ brig touch /writable/please-edit-me
$ mkdir ~/rw-data
$ brig mount ~/rw-data --root /writable
$ echo 'writable?' > ~/data/test
read-only file system: ~/data/test
$ echo 'writable!' > ~/rw-data/test
$ cat ~/rw-data/test
writable!

An existing mount can be removed again with brig unmount <path>:

$ brig unmount ~/data
$ brig unmount ~/rw-data
$ brig rm writable

Making mounts permanent

It can get a little annoying when having to manage several mounts yourself. It would be nice to have some typical mounts you’d like to have always and it should be only one command to mount or unmount all of them, kind of what mount -a does. That’s what brig fstab is for:

$ brig fstab add tmp_rw_mount /tmp/rw-mount
$ brig fstab add tmp_ro_mount /tmp/ro-mount -r
$ brig fstab
NAME          PATH           READ_ONLY  ROOT  ACTIVE
tmp_ro_mount  /tmp/ro-mount  yes        /
tmp_rw_mount  /tmp/rw-mount  no         /
$ brig fstab apply
$ brig fstab
NAME          PATH           READ_ONLY  ROOT  ACTIVE
tmp_ro_mount  /tmp/ro-mount  yes        /     ✔
tmp_rw_mount  /tmp/rw-mount  no         /     ✔
$ brig fstab apply -u
NAME          PATH           READ_ONLY  ROOT  ACTIVE
tmp_ro_mount  /tmp/ro-mount  yes        /
tmp_rw_mount  /tmp/rw-mount  no         /

Et Voilà, all mounts will be created and mounted once you enter brig fstab apply. The opposite can be achieved by executing brig fstab apply --unmount. On every restart of the daemon, all mounts are mounted by default, so the only thing you need to make sure is that the daemon is running.

Caveats: The FUSE filesystem is not yet perfect. Keep those points in mind:

  • Performance: Writing to FUSE is currently somewhat memory and CPU intensive. Generally, reading should be fast enough for most basic use cases, but also is not enough for high performance needs. If you need to edit a file many times, it is recommended to copy the file somewhere to your local storage (e.g. brig cat the_file > /tmp/the_file), edit it there and save it back for syncing purpose. Future releases will work on optimizing the performance.
  • Timeouts: Although it tries not to look like one, we’re operating on a networking filesystem. Every file you access might come from a different computer. If no other machine can serve this file we might block for a long time, causing application hangs and general slowness. This is a problem that still needs a proper solution and leaves much to be desired in the current implementation.

Remotes

Until now, all our operations were tied only to our local computer. But brig is a synchronization tool and that would be hardly very useful without supporting other peers. We call other peers »remotes« similar to the slang used in the git world.

Every remote possesses two things that identifies him:

  • A human readable name: This name can be choose by the user and can take pretty much any form, but we recommend to sticking for a form that resembles an extended email [5] like »ali@woods.org/desktop«. This name is not guaranteed to be unique! In theory everyone could take it and it is therefore only used for display purposes. There is no central place where users are registered.
  • A unique fingerprint: This serves both as address for a certain repository and as certificate of identity. It is long and hard to remember, which is the reason why brig offers to loosely link a human readable to it.

If we want to find out what our name and fingerprint is, we can use the brig whoami command to ask a very existential questions:

# NOTE: The hash will look different for you:
$ brig whoami
ali@woods.org/desktop QmTTJbkfG267gidFKfDTV4j1c843z4tkUG93Hw8r6kZ17a:W1nayTG5UMcVxy9mFFNjuZDUb7uVTnmwFYiJ4Ajr1TP3bg

Note

The fingerprint consists of two hashes divided by a colon (:). The first part is the identity of your IPFS node, the second part is the fingerprint of a keypair that was generated by brig during init and will be used to authenticate other peers.

When we want to synchronize with another repository, we need to exchange fingerprints and each other as remote. There are three typical scenarios here:

  1. Both repositories are controlled by you. In this case you can simple execute brig whoami on both repositories and add them with brig remote add as described in the following.

  2. You want to sync with somebody you know. In this case you should both execute brig whoami and send its output over a trusted side channel. Personally, I use a secure messenger like Signal, but you can also use any channel you like, including encrypted mail or meeting up with the person in question.

  3. You don’t know each other. Get to know each other and the proceed like in the second point. If you need to get a hint of what users use a certain domain, you can use brig net locate to get a list of those:

    # This command might take some time to yield results:
    $ brig net locate -m domain woods.org
    NAME           TYPE    FINGERPRINT
    ali@woods.org  domain  QmTTJbk[...]:W1UDvKzjRPb4rbbk[...]
    

    Please note again: Do not blindly add the fingerprint you see here. Always make sure the person you’re syncing with is the one you think they are.

    Todo

    This seems currently broken as it does not yield any results.

Once you have exchanged the fingerprints, you add each other as remotes. Let’s call the other side bob: [6]

$ brig remote add bob \
        QmUDSXt27LbCCG7NfNXfnwUkqwCig8RzV1wzB9ekdXaag7:
        W1e3rNGGCuuQnzyoiBKLdoN41yQ4NfNy9nRD3MwXk6h8Vy

Bob has do the same on his side. Otherwise the connection won’t be established, because the other side won’t be authenticated. By adding somebody as remote we authenticate them:

$ brig remote add ali \
QmTTJbkfG267gidFKfDTV4j1c843z4tkUG93Hw8r6kZ17a:
W1nayTG5UMcVxy9mFFNjuZDUb7uVTnmwFYiJ4Ajr1TP3bg

Thanks to the fingerprint, brig now knows how to reach the other repository over the network. This is done in the background via IPFS and might take a few moments until a valid route to the host was found.

The remote list can tell us if a remote is online:

$ brig remote list
NAME   FINGERPRINT  ROUNDTRIP  ONLINE AUTHENTICATED LASTSEEN
bob    QmUDSXt27    0s         ✔      ✔             Apr 16 17:31:01
$ brig remote ping bob
ping to bob: ✔ (0.00250s)

Nice. Now we know that bob is online (✔) and also that he authenticated us (✔). Otherwise brig remote ping bob would have failed.

Note

About open ports:

While ipfs tries to do it’s best to avoid having the user to open ports in his firewall/router. This mechanism might not be perfect though and maybe never is. If any of the following network operations might not work it might be necessary to open the port 4001 and/or enable UPnP. For security reasons we recommend to only open the required ports explicitly and not to use UPnP unless necessary. This is only necessary if the computers you’re using brig on are not in the same local network.

Choosing and finding names

You might wonder what the name you pass to init is actually for. As previously noted, there is no real restriction for choosing a name, so all of the following are indeed valid names:

  • ali
  • ali@woods.org
  • ali@woods.org/desktop
  • ali/desktop

It’s however recommended to choose a name that is formatted like a XMPP/Jabber-ID. Those IDs can look like plain emails, but can optionally have a »resource« part as suffix (separated by a »/« like desktop). Choosing such a name has two advantages:

  • Other peers can find you by only specifying parts of your name. Imagine all of the Smith family members use brig, then they’d possibly those names:

    • dad@smith.org/desktop
    • mom@smith.org/tablet
    • son@smith.org/laptop

    When dad now sets up brig on his server, he can use brig net locate -m domain 'smith.org' to get all fingerprints of all family members. Note however that brig net locate is not secure. Its purpose is solely discovery, but is not able to verify that the fingerprints really correspond to the persons they claim to be. This due to the distributed nature of brig where there is no central or federated authority that coordinate user name registrations. So it is perfectly possible that one name can be taken by several repositories - only the fingerprint is unique.

  • Later development of brig might interpret the user name and domain as email and might use your email account for verification purposes.

Having a resource part is optional, but can help if you have several instances of brig on your machines. i.e. one username could be dad@smith.org/desktop and the other dad@smith.org/server.

Syncing

Before we move on to do our first synchronization, let’s do a quick recap of what we have done so far:

  • Create a repository (brig init <name>) - This needs to be done only once.
  • Create optional mount points (brig fstab add <name> <path>) - This needs to be done only once.
  • Find & add remotes (brig remote add) - This needs to be done once for each peer.
  • Add some files (brig stage <path>) - Do as often as you like.

As you can see, there is some initial setup work, but the actual syncing is pretty effortless now. Before we attempt to sync with anybody, it’s always a good idea to see what changes they have. We can check this with brig diff <remote>:

# The "--missing" switch also tells us what files the remote does not possess:
$ brig diff bob --missing
•
├── _ hello.world
├── + videos/
└── README.md ⇄ README.md

This output resembles the one we saw from brig tree earlier. Each node in this tree tells us about something that would happen when we merge. The prefix of each file and the color in the terminal indicate what would happen with this file. Refer to the table below to see what prefix relates to what action:

Symbol Description
+ This file is only present on the remote side.
- This file was removed on the remote side.
This file was moved to a new location.
* This file was ignored because we chose to, due to our settings.
Both sides have changes, but they are compatible and can be merged.
Both sides have changes, but they are incompatible and result in conflict files.
_ This file is missing on the remote side (needs to be enabled with --missing)

Note

Remember that brig does not do any actual diffs between files. It does not care a lot about the content. It only records how the file metadata changes and what content hash the file has at a certain point.

If you prefer a more traditional view, similar to git, you can use --list on brig diff.

So in the above output we can tell that Bob added the directory /videos, but does not possess the /hello.world file. He also apparently modified README.md, but since we did not, it’s safe for us to take over his changes. If we sync now we will get this directory from him:

$ brig sync bob
$ brig ls
SIZE   MODTIME          OWNER    PATH                      PIN
443 B  Dec 27 14:44:44  ali      /README.md                🖈
443 B  Dec 27 14:44:44  bob      /README.md.conflict.0
12 B   Dec 27 15:14:16  ali      /hello.world              🖈
32 GB  Dec 27 15:14:16  bob      /videos

You might notice that the sync step took only around one second, even though /videos is 32 GB in size. This is because sync does not transfer actual data. It only transferred the metadata, while the actual data will only be loaded when required. This might sound a little inconvenient at first. When I want to watch the video, I’d prefer to have it cached locally before viewing it to avoid stuttering playback. If you plan to use the files immediately, you should be using pinning (see Pinning)

Data retrieval

If the data is not on your local machine, where is it then? Thanks to IPFS it can be transferred from any other peer that caches this particular content. Content is usually cached when the peer either really stores this file or if this peer recently used this content. In the latter case it will still be available in its cache. This property is particularly useful when having a small device for viewing data (e.g. a smartphone, granted brig would run there) and a big machine that acts as storage server (e.g. a desktop).

How are the files secure then if they essentially could be everywhere? Every file is encrypted by brig before giving it to IPFS. The encryption key is part of the metadata and is only available to the peers that you chose to synchronize with. Think of each brig repository only as a cache for the whole network it is in.

Partial synchronisation

Sometimes you only want to share certain things with certain people. You probably want to share all your /photos directory with your significant other, but not with your fellow students where you maybe want to share the /lectures folder. In brig you can define what folder you want to share with what remote. If you do not limit this, all folders will be open to a remote by default. Also note, that if a remote already got some content of a folder you did not want to share, he will still be able to access it. If you’re unsure, you should better be restrictive than too permissive.

To add a folder for a specific remote, you can use the folders subcommand of brig remote:

# Starting with next sync, bob will only see the /videos folder:
$ brig remote folder add bob /videos
$ brig remote folder ls bob
/videos

If you’re tired of typing all of this, be reminded that there are aliases for most subcommands:

$ brig rmt f a bob /videos

Pinning

How can we control what files are stored locally and which should be retrieved from the network? You can do this by pinning each file or directory you want to keep locally. Normally, files that are not pinned may be cleaned up from time to time, that means they are evaded from the local cache and need to be fetched again when being accessed afterwards. Since you still have the metadata for this file, you won’t notice difference beside possible network lag. When you pin a file, it will not be garbage collected.

brig knows of two types of pins: Explicit and implicit.

  • Implicit pins: This kind of pin is created automatically by brig and cannot be created by the user. In the command line output it always shows as blue pin. Implicit pins are created by brig whenever you create a new file, or update the contents of a file. The old version of a file will then be unpinned.
  • Explicit pins: This kind of pin is created by the user explicitly (hence the name) and is never done by brig automatically. It has the same effect as an implicit pin, but cannot be removed again by brig, unless explicitly unpinned. It’s the user’s way to tell brig »Never forgot these!«.

Note

The current pinning implementation is still under conceptual development. It’s still not clear what the best way is to modify/view the pin state of older versions. Time and user experience will tell.

When syncing with somebody, all files retrieved by them are by default not pinned. If you want to keep them for longer, make sure to pin them explicitly.

If you never pin something explicitly, only the newest version of all files will be stored locally. If you decide that you need older versions, you can pin them explicitly, so brig cannot unpin them implicitly. For this you should also look into the brig pin set and brig pin clear commands, which are similar to brig pin add and brig pin rm but can operate on whole commit ranges.

Garbage collection

Strongly related to pinning is garbage collection. This is normally being run for you every few minutes, but you can also trigger it manually via the brig gc command. While not usually needed, it can help you understand how brig works internally as it shows what hashes it throws away.

Version control

One key feature of brig over other synchronisation tools is the built-in and quite capable version control. If you already know git that’s a plus for this chapter since a lot of stuff will feel similar. This isn’t a big surprise, since brig implements something like git internally. Don’t worry, knowing git is however not needed at all for this chapter.

Key concepts

I’d like you to keep the following mantra in your head when thinking about versioning (repeating before you go to sleep may or may not help):

Metadata and actual data are separated. This means that a repository may contain metadata about many files, including older versions of them. However, it is not guaranteed that a repository caches all actual data for each file or version. This is solely controlled by pinning described in the section before. If you check out earlier versions of a file, you’re always able to see the metadata of it, but being able to view the actual data depends on having a peer that is being able to deliver the data in your network (which might be yourself). So in short: brig only versions metadata and links to the respective data for each version.

This is a somewhat novel approach to versioning, so feel free to re-read the last paragraph, since I’ve found that it does not quite fit what most people are used to. Together with pinning this offers a high degree of freedom on how you can decide what repositories store what data. The price is that this fine-tuned control can get a little annoying. Future versions of brig will try to solve that.

For some more background, you can invoke brig info to see what metadata is being saved per file version:

$ brig show README.md
Path          /README.md
User          ali
Type          file
Size          832 bytes
Inode         4
Pinned        yes
Explicit      no
ModTime       2018-10-14T22:46:00+02:00
Tree Hash     W1gX8NMQ9m8SBnjHRGtamRAjJewbnSgi6C1P7YEunfgTA3
Content Hash  W1pzHcGbVpXaePa1XpehW4HGPatDUJs8zZzSRbpNCGbN2u
Backend Hash  QmPvNjR1h56EFK1Sfb7vr7tFJ57A4JDJS9zwn7PeNbHCsK

Most of it should be no big surprise. It might be a small surprise that three hashes are stored per file. The Backend Hash is really the link to the actual data. If you’d type ipfs cat QmPvNjR1h56EFK1Sfb7vr7tFJ57A4JDJS9zwn7PeNbHCsK you will get the encrypted version of your file dumped to your terminal. The Content Hash is being calculated before the encryption and is the same for two files with the same content. The Tree Hash is a hash that uniquely identifies this specific node for internal purposes. The Inode is a number that stays unique over the lifetime of a file (including moves and removes). It is used mostly in the FUSE filesystem.

Commits

Now that we know that only metadata is versioned, we have to ask »what is the smallest unit of modification that can be saved?«. This smallest unit is a commit. A commit can be seen as a snapshot of the whole repository.

The command brig log shows you a list of commits that were made already:

      -      Sun Oct 14 22:46:00 CEST 2018(curr)
W1kAySD3aKLt Sun Oct 14 22:46:00 CEST 2018 user: Added ali-file (head)
W1ocyBsS28SD Sun Oct 14 22:46:00 CEST 2018 user: Added initial README.md
W1D9KsLNnAv4 Sun Oct 14 22:46:00 CEST 2018 initial commit (init)

Each commit is identified by a hash (e.g. W1kAySD3aKLt) and records the time when it was created. Apart from that, there is a message that describes the commit in some way. In contrast to git, commits are rarely done by the user themselve. More often they are done by brig when synchronizing.

All commits form a long chain (no branches, just a linear chain) with the very first empty commit called init and the still unfinished commit called curr. Directly below curr there is the last finished commit called head.

Note

curr is what git users would call the staging area. While the staging area in git is “special”, the curr commit can be used like any other one, with the sole difference that it does not have a proper hash yet.

Sometimes you might want to do a snapshot or »savepoint« yourself. In this case you can do a commit yourself:

$ brig touch A_NEW_FILE
$ brig commit -m 'better leave some breadcrumbs'
$ brig log | head -n 2
      -      Mon Oct 15 00:27:37 CEST 2018(curr)
W1hZoY7TrxyK Sun Oct 14 22:46:00 CEST 2018 user: better leave some bread crumbs (head)

This snapshot can be useful later if you decide to revert to a certain version. The hash of the commit is of course hard to remember, so if you need it very often, you can give it a tag yourself. Tags are similar to the names, curr, head and init but won’t be changed by brig and won’t move therefore:

# instead of "W1hZoY7TrxyK" you also could use "head" here:
$ brig tag W1hZoY7TrxyK breadcrumbs
$ brig log | grep breadcrumbs
$ W1hZoY7TrxyK Sun Oct 14 22:46:00 CEST 2018 user: better leave some bread crumbs (breadcrumbs, head)

File history

Each file and directory in brig maintains its own history. Each entry of this history relates to exactly one distinct commit. In the life of a file or directory there are four things that can happen to it:

  • added: The file was added in this commit.
  • moved: The file was moved in this commit.
  • removed: The file was removed in this commit.
  • modified: The file’s content (i.e. hash changed) was altered in this commit.

You can check an individual file or directorie’s history by using the brig history command:

# or "hst" for short:
$ brig hst README.md
CHANGE  FROM  TO              WHEN
added   INIT  W1ocyBsS28SD    Oct 14 22:46:00
$ brig mv README.md README_LATER.md
$ brig hst README_LATER.md
CHANGE  FROM  TO            HOW                           WHEN
moved   HEAD  CURR          /README.md → /README_LATER.md Oct 15 00:27:37
added   INIT  W1ocyBsS28SD                                Oct 14 22:46:0

As you can see, you will be shown one line per history entry. Each entry denotes which commit the change was in. Some commits were nothing was changed will be jumped over except if you pass --empty.

Viewing differences

If you’re interested what changed in a range of your own commits, you can use the brig diff command as shown previously. The -s (--self) switch says that we want to compare only two of our own commits (as opposed to comparing with the commits of a remote).

# Let's compare the commit hashes from above:
$ brig diff -s W1hZoY7TrxyK W1kAySD3aKLt
•
└── + A_NEW_FILE

Often, those hashes are quite hard to remember and annoying to look up. That’s why you can the special syntax <tag or hash>^ to denote that you want to go »one commit up«:

brig diff -s head head^
•
└── + A_NEW_FILE
# You can also use this several times:
brig diff -s head^^^ head^^^^^
•
└── + README.md

If you just want to see what you changed since head, you can simply type brig diff. This is the same as brig diff -s curr head:

$ brig diff
•
└── README.md → README_LATER.md
$ brig diff -s curr head
•
└── README.md → README_LATER.md

Reverting to previous state

Until now we were only looking at the version history and didn’t modify it. The most versatile command to do that is brig reset. It is able to revert changes previously made:

# Reset to the "init" commit (the very first and empty commit)
$ brig reset init
$ brig ls  # nothing, it's empty.

The key here is that you did not loose any history:

$ brig log | head -2
       -     Mon Oct 15 00:51:12 CEST 2018(curr)
W1hZoY7TrxyK Sun Oct 14 22:46:00 CEST 2018 user: better leave some bread crumbs (breadcrumbs)

As you can see, we still have the previous commits. brig revert did one thing more than restoring the state of init and put that result in curr. This also means that you can’t really modify history. But you can revert it. Let’s revert your complete wipe-out:

# Reset to the state we had in »breadcrumbs«
$ brig reset breadcrumbs

brig reset cannot only restore old commits, but individual files and directories:

$ brig reset head^^ README.md

Note

It is a good idea to do a brig commit before a brig reset. Since it modifies curr you might loose uncommitted changes. It will warn you about that, but you can overwrite that warning with --force. If you did a brig commit you can simply use brig reset head to go back to the last good state.

Nodes that were overwritten with brig reset will be unpinned (unless pinned explicitly). Those nodes and their content will be garbage collected after some time. The content may still be accessed through the use of other remotes though.

Other commands

There are a few other commands, but they are not (yet) very useful for most end users. Therefore they will not be explained in depth to save you some mental space. The commands in question are:

  • brig become: View the metadata of another remote. Good for debugging.
  • brig daemon: Start the daemon manually. Good for init systems like systemd.
  • brig net: Commands to modify the network status and find other peers.
  • brig edit: Edit a file in brig with the $EDITOR. Good for quick edits.
  • brig fetch: Manually trigger the fetching of a remote’s metadata. Also good for debugging.

Please use brig help <command> to find out more about them if you’re interested.

Configuration

Quite a few details can be configured in a different way to your liking. brig config is the command that allows you to list, get and set individual configuration values. Each config entry already brings some documentation that tells you about its purpose:

$ brig config ls
[... output truncated ...]
fs.sync.ignore_moved: false (default)
Default:       false
Documentation: Do not move what the remote moved
Needs restart: no
[... output truncated ...]
$ brig config get repo.password_command
pass brig/repo/password
$ brig config set repo.password_command "pass brig/repo/my-password"

Using the gateway

Many users will not run brig. Chances are, that you still want to send them your files without too much hassle. brig features a Gateway to HTTP(S), which comes particularly handy if you happen to run a public server.

The gateway is disabled by default. If you want to start it, use this command:

$ brig gateway start

Without further configuration, this will create a HTTP server on port 5000, which can be queried already. There is a small helper that will print you a nice hyperlink to a certain file called brig gateway url:

$ brig gateway url README.md
http://localhost:5000/get/README.md

Opening this in your browser will show you the file’s content. If you’d like to use another port than 5000, you can do so by setting the respective config key:

$ brig cfg set gateway.port 7777

Note

You can always check the status of the gateway:

$ brig gateway status

This will also print helpful diagnostics if something might be wrong.

The gateway can be stopped anytime with the following command. It tries to still serve all open requests, so that no connections are dropped:

$ brig gateway stop

Note

If you want to forward the gateway to the outside, but do not own a dedicated server, you can forward port 5000 to your computer. With this setup you should also get a certficate which in turn requires a DNS name. An easy way to get one is to use dynamic DNS.

Securing access

You probably do not want to offer your files to everyone that have a link. Therefore you can restrict access to a few folders (/public for example) and require a user to authenticate himself with a user and password upon access.

By default all files are accessible. You can change this by changing the config:

$ brig cfg set gateway.folders /public

Now only the files in /public (and including /public itself) are accessible from the gateway. If you want to add basic HTTP authentication:

$ brig cfg set gateway.auth.enabled true
$ brig cfg set gateway.auth.user <user>
$ brig cfg set gateway.auth.pass <pass>

If you use authentication, it is strongly recommended to enable HTTPS. Otherwise the password will be transmitted in clear text.

Running the gateway with HTTPS

The gateway has built-in support for LetsEncrypt. If the gateway is reachable under a DNS name, it is straightforward to get a TLS certificate for it. In total there are three methods:

Method one: Automatic: This works by telling the gateway the domain name. Since the retrieval process for getting a certificate involves binding on port 80, you need to prepare the brig binary to allow that without running as root:

# You need to restart the brig daemon for that.
# Every next brig command will restart it.
$ brig daemon quit
$ sudo setcap CAP_NET_BIND_SERVICE=+ep $(which brig)

Afterwards you can set the domain in the config. If the gateway is already running, it will restart immediately.

$ brig cfg set gateway.cert.domain your.domain.org

You can check after a few seconds if it worked by checking if the certfile and keyfile was set:

$ brig cfg get gateway.cert.certfile
/home/user/.cache/brig/your.domain.org_cert.pem
$ brig cfg get gateway.cert.keyfile
/home/user/.cache/brig/your.domain.org_key.pem
$ curl -i https://your.domain.org:5000
HTTP/2 200
vary: Accept-Encoding
content-type: text/plain; charset=utf-8
content-length: 38
date: Wed, 05 Dec 2018 11:53:57 GMT

This brig gateway seems to be working.

This method has the advantage that the certificate can be updated automatically before it expires.

Method two: Half-Automated:

If the above did not work for whatever reasons, you can try to get a certificate manually. There is a built-in helper called brig gateway cert that can help you doing that:

$ brig gateway cert your.domain.org
You are not root. We need root rights to bind to port 80.
I will re-execute this command for you as:
$ sudo brig gateway cert nwzmlh4iouqikobq.myfritz.net --cache-dir /home/sahib/.cache/brig

A certificate was downloaded successfully.
Successfully set the gateway config to use the certificate.
Note that you have to re-run this command every 90 days currently.

If successful, this command will set the certfile and keyfile config values for you. You can test if the change worked by doing the same procedure as in method one. Sadly, you have to re-execute once the certificate expires.

Method three: Manual:

If you already own a certificate you can make the gateway use it by setting the path to the public certificate and the private key file:

$ brig cfg set gateway.cert.certfile /path/to/cert.pem
$ brig cfg set gateway.cert.keyfile /path/to/key.pem

If you do not own a certificate yet, but want to setup an automated way to download one for usages outside of brig, you should look into certbot.

Redirecting HTTP traffic

This section only applies to you if you choose method one from above and want to run the gateway on port 80 (http) and port 443 (https). This has the advantage that a user does not need to specify the port in a gateway URL have which looks a little bit less »scary«. With this setup all traffic on port 80 will be redirected directly to port 443.

$ brig cfg set gateway.port 443
$ brig cfg set gateway.cert.redirect.enabled true
$ brig cfg set gateway.cert.redirect.http_port 80

Running the daemon and viewing logs

As discussed before, the daemon is being started on demand in the background. Subsequent commands will then use the daemon. For debugging purposes it can be useful to run in the daemon in the foreground. You can do this with the brig daemon commands:

# Make sure no prior daemon is running:
$ brig daemon quit
# Start the daemon in the foreground and log to stdout:
$ brig daemon launch -s

The last step will ask for your password if you did not set a password helper program. If you want to quit the instance, either just hit CTRL-C or type brig daemon quit into another terminal window.

Logging

Unless you pass the -s (--log-to-stdout flag) all logs are being piped to the system log. You can follow the log like this:

# The actual daemon log:
$ journalctl -ft brig

# The ipfs log:
$ journalctl -ft brig-ipfs

This assumes you’re using a systemd-based distribution. If not, refer to the documentation of your syslog daemon.

Using several repositories in parallel

It can be useful to run more than one instance of the brig daemon in parallel. Either for testing purposes or as actual production configuration. If you’re planning to do that it is advisable to be always explicit about the port number you’re using. Here’s an example how you can run two daemons at the same time:

# It might be a good idea to keep that in your .bashrc:
alias brig-ali='brig --port 6666'
alias brig-bob='brig --port 6667'

# Subsitute your password helper here:
brig-ali --repo /tmp/ali init ali -w "echo brig/repo/ali"
brig-bob --repo /tmp/bob init bob -w "echo brig/repo/bob"

# Now you can use them normally,
# e.g. by adding them as remotes each:
brig-ali remote add bob $(brig-bob whoami -f)
brig-bob remote add ali $(brig-ali whoami -f)

[1]This uses Dropbox’s password strength library »zxcvbn«.
[2]Pinning and pin states are explained Pinning and are not important for now.
[3]brig rm for example deletes directories without needing a -r switch.
[4]Well almost. See the Caveats below.
[5]To be more exact, it resembles an XMPP or Jabber-ID.
[6]The name you choose as remote can be anything you like and does not need to match the name the other person chose for themselves. It’s not a bad idea though.