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.. into HTML or text. In the future we plan to extract the example commands
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.. and automatically test them.
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.. This text was previously on the wiki at
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.. This text was previously on the wiki at
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.. http://bazaar.canonical.com/IntroductionToBzr
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.. but has been moved into the source tree so it can be kept in sync with
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.. the source and possibly automatically checked.
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Current for bzr-0.91, 2007-08
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If you are already familiar with decentralized version control, then
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If you are already familiar with decentralized revision control, then
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please feel free to skip ahead to "Introducing Yourself to Bazaar". If,
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on the other hand, you are familiar with version control but not
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decentralized version control, then please start at "How DVCS is
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on the other hand, you are familiar with revision control but not
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decentralized revision control, then please start at "How DRCS is
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different." Otherwise, get some coffee or tea, get comfortable and get
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The purpose of version control
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==============================
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The Purposes of Revision Control
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================================
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Odds are that you have worked on some sort of textual data -- the sources
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to a program, web sites or the config files that Unix system
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important information that you would desperately like to get back. If this
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has ever happened to you, then you are probably ready for Bazaar.
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Version control systems (which I'll henceforth call VCS) such as
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Revision control systems (which I'll henceforth call RCS) such as
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Bazaar give you the ability to track changes for a directory by turning
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it into something slightly more complicated than a directory that we call
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a **branch**. The branch not only stores how the directory looks right
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do something you wish you hadn't, you can restore the directory to the way
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it looked at some point in the past.
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Version control systems give users the ability to save changes to a
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Revision control systems give users the ability to save changes to a
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branch by "committing a **revision**". The revision created is essentially
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a summary of the changes that were made since the last time the tree was
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These revisions have other uses as well. For example, one can comment
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revisions to record what the recent set of changes meant by providing an
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optional log message. Real life log messages include things like "Fixed
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the web template to close the table" and "Added SFTP suppport. Fixes #595"
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the web template to close the table" and "Added sftp suppport. Fixes #595"
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We keep these logs so that if later there is some sort of problem with
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SFTP, we can figure out when the problem probably happened.
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Many Version Control Systems (VCS) are stored on servers. If one wants to
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work on the code stored within a VCS, then one needs to connect to the
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sftp, we can figure out when the problem probably happened.
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Many Revision Control Systems (RCS) are stored on servers. If one wants to
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work on the code stored within an RCS, then one needs to connect to the
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server and "checkout" the code. Doing so gives one a directory in which a
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person can make changes and then commit. The VCS client then connects to
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the VCS server and stores the changes. This method is known as the
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person can make changes and then commit. The RCS client then connects to
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the RCS server and stores the changes. This method is known as the
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The centralized model can have some drawbacks. A centralized VCS requires
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The centralized model can have some drawbacks. A centralized RCS requires
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that one is able to connect to the server whenever one wants to do version
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control work. This can be a bit of a problem if your server is on some other
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machine on the internet and you are not. Or, worse yet, you **are** on the
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internet but the server is missing!
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Decentralized Version Control Systems (which I'll call DVCS after this
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Decentralized Revision Control Systems (which I'll call DRCS after this
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point) deal with this problem by keeping branches on the same machine as
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the client. In Bazaar's case, the branch is kept in the same place as
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the code that is being version controlled. This allows the user to save
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user only needs internet access when he wants to access the changes in
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someone else's branch that are somewhere else.
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A common requirement that many people have is the need to keep track of
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the changes for a directory such as file and subdirectory changes.
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Performing this tracking by hand is a awkward process that over time
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becomes unwieldy. That is, until one considers version control tools such
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as Bazaar. These tools automate the process of storing data by creating
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a **revision** of the directory tree whenever the user asks.
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a **revision** of the directory tree whenever the user asks.
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Version control software such as Bazaar can do much more than just
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Revision control software such as Bazaar can do much more than just
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storage and performing undo. For example, with Bazaar a developer can
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take the modifications in one branch of software and apply them to a
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related branch -- even if those changes exist in a branch owned by
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==============================
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Bazaar installs a single new command, **bzr**. Everything else is a
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subcommand of this. You can get some help with ``bzr help``. Some arguments
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subcommand of this. You can get some help with ``bzr help``. Some arguments
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are grouped in topics: ``bzr help topics`` to see which topics are available.
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One function of a version control system is to keep track of who changed
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address by looking up your username and hostname. If you don't like the
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guess that Bazaar makes, then three options exist:
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1. Set an email address via ``bzr whoami``. This is the simplest way.
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To set a global identity, use::
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% bzr whoami "Your Name <email@example.com>"
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If you'd like to use a different address for a specific branch, enter
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the branch folder and use::
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% bzr whoami --branch "Your Name <email@example.com>"
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#. Setting the email address in the ``~/.bazaar/bazaar.conf`` [1]_ by
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adding the following lines. Please note that ``[DEFAULT]`` is case
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email=Your Name <email@isp.com>
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As above, you can override this settings on a branch by branch basis
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by creating a branch section in ``~/.bazaar/locations.conf`` and
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adding the following lines::
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[/the/path/to/the/branch]
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email=Your Name <email@isp.com>
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#. Overriding the two previous options by setting the global environment
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variable ``$BZR_EMAIL`` or ``$EMAIL`` (``$BZR_EMAIL`` will take
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precedence) to your full email address.
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1. Set an email address via ``bzr whoami``. This is the simplest way.
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To set a global identity, use::
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% bzr whoami "Your Name <email@example.com>"
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If you'd like to use a different address for a specific branch, enter
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the branch folder and use::
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% bzr whoami --branch "Your Name <email@example.com>"
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#. Setting the email address in the ``~/.bazaar/bazaar.conf`` [1]_ by
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adding the following lines. Please note that ``[DEFAULT]`` is case
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email=Your Name <email@isp.com>
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As above, you can override this settings on a branch by branch basis
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by creating a branch section in ``~/.bazaar/locations.conf`` and
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adding the following lines::
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[/the/path/to/the/branch]
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email=Your Name <email@isp.com>
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#. Overriding the two previous options by setting the global environment
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variable ``$BZR_EMAIL`` or ``$EMAIL`` (``$BZR_EMAIL`` will take
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precedence) to your full email address.
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.. [1] On Windows, the users configuration files can be found in the
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application data directory. So instead of ``~/.bazaar/branch.conf``
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the configuration file can be found as:
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the configuration file can be found as:
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``C:\Documents and Settings\<username>\Application Data\Bazaar\2.0\branch.conf``.
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The same is true for ``locations.conf``, ``ignore``, and the
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``plugins`` directory.
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You'll usually refer to branches on your computer's filesystem just by
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giving the name of the directory containing the branch. bzr also supports
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accessing branches over SSH, HTTP and SFTP, amongst other things::
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accessing branches over http and sftp, for example::
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% bzr log bzr+ssh://bazaar.launchpad.net/~bzr-pqm/bzr/bzr.dev/
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% bzr log http://bazaar.launchpad.net/~bzr-pqm/bzr/bzr.dev/
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% bzr log sftp://bazaar.launchpad.net/~bzr-pqm/bzr/bzr.dev/
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% bzr log http://bazaar-vcs.org/bzr/bzr.dev/
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% bzr log sftp://bazaar-vcs.org/bzr/bzr.dev/
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By installing bzr plugins you can also access branches using the rsync
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its test suite before committing, to make sure that every revision is a
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known-good state. You can also review your changes, to make sure you're
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committing what you intend to, and as a chance to rethink your work before
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you permanently record it.
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you permanently record it.
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Two bzr commands are particularly useful here: **status** and **diff**.
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Two bzr commands are particularly useful here: **status** and **diff**.
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Some projects prefer patches to show a prefix at the start of the path
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for old and new files. The ``--prefix`` option can be used to provide
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As a shortcut, ``bzr diff -p1`` produces a form that works with the
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As a shortcut, ``bzr diff -p1`` produces a form that works with the
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command ``patch -p1``.
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Committing changes
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==================
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When the working tree state is satisfactory, it can be **committed** to
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the branch, creating a new revision holding a snapshot of that state.
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the branch, creating a new revision holding a snapshot of that state.
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commit message when you have finished. If you would like parts to be
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included in the message you can copy and paste them above the separator.
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Marking bugs as fixed
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---------------------
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Many changes to a project are as a result of fixing bugs. Bazaar can keep
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metadata about bugs you fixed when you commit them. To do this you use the
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``--fixes`` option. This option takes an argument that looks like this::
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% bzr commit --fixes <tracker>:<id>
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Where ``<tracker>`` is an identifier for a bug tracker and ``<id>`` is an
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identifier for a bug that is tracked in that bug tracker. ``<id>`` is usually
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a number. Bazaar already knows about a few popular bug trackers. They are
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bugs.launchpad.net, bugs.debian.org, and bugzilla.gnome.org. These trackers
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have their own identifiers: lp, deb, and gnome respectively. For example,
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if you made a change to fix the bug #1234 on bugs.launchpad.net, you would
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use the following command to commit your fix::
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% bzr commit -m "fixed my first bug" --fixes lp:1234
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For more information on this topic or for information on how to configure
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other bug trackers please read `Bug Tracker Settings`_.
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.. _Bug Tracker Settings: ../user-reference/index.html#bug-tracker-settings
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given then only those ones will be affected. ``bzr revert`` also clears the
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list of pending merges revisions.
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Many source trees contain some files that do not need to be versioned,
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such as editor backups, object or bytecode files, and built programs. You
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can simply not add them, but then they'll always crop up as unknown files.
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% bzr commit -m "Add ignore patterns"
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As an alternative to editing the ``.bzrignore`` file, you can use the
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``bzr ignore`` command. The ``bzr ignore`` command takes filenames and/or
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patterns as arguments and then adds them to the ``.bzrignore`` file. If a
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``.bzrignore`` file does not exist the ``bzr ignore`` command will
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automatically create one for you, and implicitly add it to be versioned::
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Just like when editing the ``.bzrignore`` file on your own, you should
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commit the automatically created ``.bzrignore`` file::
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% bzr commit -m "Added tags to ignore file"
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There are some ignored files which are not project specific, but more user
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directory. This is a bit different to CVS, which requires that you also
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do ``cvs remove``.
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``bzr remove`` makes the file un-versioned, but may or may not delete the
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working copy [2]_. This is useful when you add the wrong file, or decide that
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a file should actually not be versioned.
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``bzr remove`` makes the file un-versioned, but may or may not delete
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the working copy [2]_. This is useful when you add the wrong file,
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or decide that a file should actually not be versioned.
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After this change, the local directory will be a mirror of the source. This
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includes the ''revision-history'' - which is a list of the commits done in
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includes the ''revision-history'' - which is a list of the commits done in
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this branch, rather than merged from other branches.
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This command only works if your local (destination) branch is either an
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uses rsync to push the changes to the revision history and the working
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* You can also copy the files around manually, by sending a tarball, or using
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rsync, or other related file transfer methods. This is usually less safe
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than using ``push``, but may be faster or easier in some situations.
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Moving changes between trees
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You can also use copy the files around manually, by sending a tarball, or
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using rsync, or other related file transfer methods. This is usually
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less safe than using ``push``, but may be faster or easier in some
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Moving changes between trees
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============================
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It happens to the best of us: sometimes you'll make changes in the wrong