From 6679c34c47be19ba8e9ea72129dfe768a49c5ab4 Mon Sep 17 00:00:00 2001 From: Pete Wyckoff Date: Sat, 24 Dec 2011 21:07:31 -0500 Subject: [PATCH] git-p4: introduce asciidoc documentation Add proper documentation for git-p4. Delete the old .txt documentation from contrib/fast-import. Cc: Frans Klaver Cc: Luke Diamand Signed-off-by: Pete Wyckoff Signed-off-by: Junio C Hamano --- Documentation/git-p4.txt | 455 +++++++++++++++++++++++++++++++++ contrib/fast-import/git-p4.txt | 302 ---------------------- 2 files changed, 455 insertions(+), 302 deletions(-) create mode 100644 Documentation/git-p4.txt delete mode 100644 contrib/fast-import/git-p4.txt diff --git a/Documentation/git-p4.txt b/Documentation/git-p4.txt new file mode 100644 index 000000000..201a0a03c --- /dev/null +++ b/Documentation/git-p4.txt @@ -0,0 +1,455 @@ +git-p4(1) +========= + +NAME +---- +git-p4 - Import from and submit to Perforce repositories + + +SYNOPSIS +-------- +[verse] +'git p4 clone' [] [] ... +'git p4 sync' [] [...] +'git p4 rebase' +'git p4 submit' [] [] + + +DESCRIPTION +----------- +This command provides a way to interact with p4 repositories +using git. + +Create a new git repository from an existing p4 repository using +'git p4 clone', giving it one or more p4 depot paths. Incorporate +new commits from p4 changes with 'git p4 sync'. The 'sync' command +is also used to include new branches from other p4 depot paths. +Submit git changes back to p4 using 'git p4 submit'. The command +'git p4 rebase' does a sync plus rebases the current branch onto +the updated p4 remote branch. + + +EXAMPLE +------- +* Create an alias for 'git p4', using the full path to the 'git-p4' + script if needed: ++ +------------ +$ git config --global alias.p4 '!git-p4' +------------ + +* Clone a repository: ++ +------------ +$ git p4 clone //depot/path/project +------------ + +* Do some work in the newly created git repository: ++ +------------ +$ cd project +$ vi foo.h +$ git commit -a -m "edited foo.h" +------------ + +* Update the git repository with recent changes from p4, rebasing your + work on top: ++ +------------ +$ git p4 rebase +------------ + +* Submit your commits back to p4: ++ +------------ +$ git p4 submit +------------ + + +COMMANDS +-------- + +Clone +~~~~~ +Generally, 'git p4 clone' is used to create a new git directory +from an existing p4 repository: +------------ +$ git p4 clone //depot/path/project +------------ +This: + +1. Creates an empty git repository in a subdirectory called 'project'. ++ +2. Imports the full contents of the head revision from the given p4 +depot path into a single commit in the git branch 'refs/remotes/p4/master'. ++ +3. Creates a local branch, 'master' from this remote and checks it out. + +To reproduce the entire p4 history in git, use the '@all' modifier on +the depot path: +------------ +$ git p4 clone //depot/path/project@all +------------ + + +Sync +~~~~ +As development continues in the p4 repository, those changes can +be included in the git repository using: +------------ +$ git p4 sync +------------ +This command finds new changes in p4 and imports them as git commits. + +P4 repositories can be added to an existing git repository using +'git p4 sync' too: +------------ +$ mkdir repo-git +$ cd repo-git +$ git init +$ git p4 sync //path/in/your/perforce/depot +------------ +This imports the specified depot into +'refs/remotes/p4/master' in an existing git repository. The +'--branch' option can be used to specify a different branch to +be used for the p4 content. + +If a git repository includes branches 'refs/remotes/origin/p4', these +will be fetched and consulted first during a 'git p4 sync'. Since +importing directly from p4 is considerably slower than pulling changes +from a git remote, this can be useful in a multi-developer environment. + + +Rebase +~~~~~~ +A common working pattern is to fetch the latest changes from the p4 depot +and merge them with local uncommitted changes. Often, the p4 repository +is the ultimate location for all code, thus a rebase workflow makes +sense. This command does 'git p4 sync' followed by 'git rebase' to move +local commits on top of updated p4 changes. +------------ +$ git p4 rebase +------------ + + +Submit +~~~~~~ +Submitting changes from a git repository back to the p4 repository +requires a separate p4 client workspace. This should be specified +using the 'P4CLIENT' environment variable or the git configuration +variable 'git-p4.client'. The p4 client must exist, but the client root +will be created and populated if it does not already exist. + +To submit all changes that are in the current git branch but not in +the 'p4/master' branch, use: +------------ +$ git p4 submit +------------ + +To specify a branch other than the current one, use: +------------ +$ git p4 submit topicbranch +------------ + +The upstream reference is generally 'refs/remotes/p4/master', but can +be overridden using the '--origin=' command-line option. + +The p4 changes will be created as the user invoking 'git p4 submit'. The +'--preserve-user' option will cause ownership to be modified +according to the author of the git commit. This option requires admin +privileges in p4, which can be granted using 'p4 protect'. + + +OPTIONS +------- + +General options +~~~~~~~~~~~~~~~ +All commands except clone accept this option. + +--git-dir :: + Set the 'GIT_DIR' environment variable. See linkgit:git[1]. + +Sync options +~~~~~~~~~~~~ +These options can be used in the initial 'clone' as well as in +subsequent 'sync' operations. + +--branch :: + Import changes into given branch. If the branch starts with + 'refs/', it will be used as is, otherwise the path 'refs/heads/' + will be prepended. The default branch is 'master'. + +--detect-branches:: + Use the branch detection algorithm to find new paths in p4. It is + documented below in "BRANCH DETECTION". + +--changesfile :: + Import exactly the p4 change numbers listed in 'file', one per + line. Normally, 'git p4' inspects the current p4 repository + state and detects the changes it should import. + +--silent:: + Do not print any progress information. + +--verbose:: + Provide more progress information. + +--detect-labels:: + Query p4 for labels associated with the depot paths, and add + them as tags in git. + +--import-local:: + By default, p4 branches are stored in 'refs/remotes/p4/', + where they will be treated as remote-tracking branches by + linkgit:git-branch[1] and other commands. This option instead + puts p4 branches in 'refs/heads/p4/'. + +--max-changes :: + Limit the number of imported changes to 'n'. Useful to + limit the amount of history when using the '@all' p4 revision + specifier. + +--keep-path:: + The mapping of file names from the p4 depot path to git, by + default, involves removing the entire depot path. With this + option, the full p4 depot path is retained in git. For example, + path '//depot/main/foo/bar.c', when imported from + '//depot/main/', becomes 'foo/bar.c'. With '--keep-path', the + git path is instead 'depot/main/foo/bar.c'. + +--use-client-spec:: + Use a client spec to find the list of interesting files in p4. + The client spec is discovered using 'p4 client -o' which checks + the 'P4CLIENT' environment variable and returns a mapping of + depot files to workspace files. + +Clone options +~~~~~~~~~~~~~ +These options can be used in an initial 'clone', along with the 'sync' +options described above. + +--destination :: + Where to create the git repository. If not provided, the last + component in the p4 depot path is used to create a new + directory. + +--bare:: + Perform a bare clone. See linkgit:git-clone[1]. + +-/ :: + Exclude selected depot paths when cloning. + +Submit options +~~~~~~~~~~~~~~ +These options can be used to modify 'git p4 submit' behavior. + +--verbose:: + Provide more progress information. + +--origin :: + Upstream location from which commits are identified to submit to + p4. By default, this is the most recent p4 commit reachable + from 'HEAD'. + +-M[]:: + Detect renames. See linkgit:git-diff[1]. Renames will be + represented in p4 using explicit 'move' operations. + +--preserve-user:: + Re-author p4 changes before submitting to p4. This option + requires p4 admin privileges. + + +DEPOT PATH SYNTAX +----------------- +The p4 depot path argument to 'git p4 sync' and 'git p4 clone' can +be one or more space-separated p4 depot paths, with an optional +p4 revision specifier on the end: + +"//depot/my/project":: + Import one commit with all files in the '#head' change under that tree. + +"//depot/my/project@all":: + Import one commit for each change in the history of that depot path. + +"//depot/my/project@1,6":: + Import only changes 1 through 6. + +"//depot/proj1 //depot/proj2@all":: + Import all changes from both named depot paths. + +See 'p4 help revisions' for the full syntax of p4 revision specifiers. + + +BRANCH DETECTION +---------------- +P4 does not have the same concept of a branch as git. Instead, +p4 organizes its content as a directory tree, where by convention +different logical branches are in different locations in the tree. +The 'p4 branch' command is used to maintain mappings between +different areas in the tree, and indicate related content. 'git p4' +can use these mappings to determine branch relationships. + +If you have a repository where all the branches of interest exist as +subdirectories of a single depot path, you can use '--detect-branches' +when cloning or syncing to have 'git p4' automatically find +subdirectories in p4, and to generate these as branches in git. + +For example, if the P4 repository structure is: +---- +//depot/main/... +//depot/branch1/... +---- + +And "p4 branch -o branch1" shows a View line that looks like: +---- +//depot/main/... //depot/branch1/... +---- + +Then this 'git p4 clone' command: +---- +git p4 clone --detect-branches //depot@all +---- +produces a separate branch in 'refs/remotes/p4/' for //depot/main, +called 'master', and one for //depot/branch1 called 'depot/branch1'. + +However, it is not necessary to create branches in p4 to be able to use +them like branches. Because it is difficult to infer branch +relationships automatically, a git configuration setting +'git-p4.branchList' can be used to explicitly identify branch +relationships. It is a list of "source:destination" pairs, like a +simple p4 branch specification, where the "source" and "destination" are +the path elements in the p4 repository. The example above relied on the +presence of the p4 branch. Without p4 branches, the same result will +occur with: +---- +git config git-p4.branchList main:branch1 +git p4 clone --detect-branches //depot@all +---- + + +PERFORMANCE +----------- +The fast-import mechanism used by 'git p4' creates one pack file for +each invocation of 'git p4 sync'. Normally, git garbage compression +(linkgit:git-gc[1]) automatically compresses these to fewer pack files, +but explicit invocation of 'git repack -adf' may improve performance. + + +CONFIGURATION VARIABLES +----------------------- +The following config settings can be used to modify 'git p4' behavior. +They all are in the 'git-p4' section. + +General variables +~~~~~~~~~~~~~~~~~ +git-p4.user:: + User specified as an option to all p4 commands, with '-u '. + The environment variable 'P4USER' can be used instead. + +git-p4.password:: + Password specified as an option to all p4 commands, with + '-P '. + The environment variable 'P4PASS' can be used instead. + +git-p4.port:: + Port specified as an option to all p4 commands, with + '-p '. + The environment variable 'P4PORT' can be used instead. + +git-p4.host:: + Host specified as an option to all p4 commands, with + '-h '. + The environment variable 'P4HOST' can be used instead. + +git-p4.client:: + Client specified as an option to all p4 commands, with + '-c '. This can also be used as a way to find + the client spec for the 'useClientSpec' option. + The environment variable 'P4CLIENT' can be used instead. + +Clone and sync variables +~~~~~~~~~~~~~~~~~~~~~~~~ +git-p4.syncFromOrigin:: + Because importing commits from other git repositories is much faster + than importing them from p4, a mechanism exists to find p4 changes + first in git remotes. If branches exist under 'refs/remote/origin/p4', + those will be fetched and used when syncing from p4. This + variable can be set to 'false' to disable this behavior. + +git-p4.branchUser:: + One phase in branch detection involves looking at p4 branches + to find new ones to import. By default, all branches are + inspected. This option limits the search to just those owned + by the single user named in the variable. + +git-p4.branchList:: + List of branches to be imported when branch detection is + enabled. Each entry should be a pair of branch names separated + by a colon (:). This example declares that both branchA and + branchB were created from main: +------------- +git config git-p4.branchList main:branchA +git config --add git-p4.branchList main:branchB +------------- + +git-p4.useClientSpec:: + Specify that the p4 client spec to be used to identify p4 depot + paths of interest. This is equivalent to specifying the option + '--use-client-spec'. The variable 'git-p4.client' can be used + to specify the name of the client. + +Submit variables +~~~~~~~~~~~~~~~~ +git-p4.detectRenames:: + Detect renames. See linkgit:git-diff[1]. + +git-p4.detectCopies:: + Detect copies. See linkgit:git-diff[1]. + +git-p4.detectCopiesHarder:: + Detect copies harder. See linkgit:git-diff[1]. + +git-p4.preserveUser:: + On submit, re-author changes to reflect the git author, + regardless of who invokes 'git p4 submit'. + +git-p4.allowMissingP4Users:: + When 'preserveUser' is true, 'git p4' normally dies if it + cannot find an author in the p4 user map. This setting + submits the change regardless. + +git-p4.skipSubmitEdit:: + The submit process invokes the editor before each p4 change + is submitted. If this setting is true, though, the editing + step is skipped. + +git-p4.skipSubmitEditCheck:: + After editing the p4 change message, 'git p4' makes sure that + the description really was changed by looking at the file + modification time. This option disables that test. + +git-p4.allowSubmit:: + By default, any branch can be used as the source for a 'git p4 + submit' operation. This configuration variable, if set, permits only + the named branches to be used as submit sources. + +git-p4.skipUserNameCheck:: + If the user running 'git p4 submit' does not exist in the p4 + user map, 'git p4' exits. This option can be used to force + submission regardless. + + +IMPLEMENTATION DETAILS +---------------------- +* Changesets from p4 are imported using git fast-import. +* Cloning or syncing does not require a p4 client; file contents are + collected using 'p4 print'. +* Submitting requires a p4 client, which is not in the same location + as the git repository. Patches are applied, one at a time, to + this p4 client and submitted from there. +* Each commit imported by 'git p4' has a line at the end of the log + message indicating the p4 depot location and change number. This + line is used by later 'git p4 sync' operations to know which p4 + changes are new. diff --git a/contrib/fast-import/git-p4.txt b/contrib/fast-import/git-p4.txt deleted file mode 100644 index 5044a121e..000000000 --- a/contrib/fast-import/git-p4.txt +++ /dev/null @@ -1,302 +0,0 @@ -git-p4 - Perforce <-> Git converter using git-fast-import - -Usage -===== - -git-p4 can be used in two different ways: - -1) To import changes from Perforce to a Git repository, using "git-p4 sync". - -2) To submit changes from Git back to Perforce, using "git-p4 submit". - -Importing -========= - -Simply start with - - git-p4 clone //depot/path/project - -or - - git-p4 clone //depot/path/project myproject - -This will: - -1) Create an empty git repository in a subdirectory called "project" (or -"myproject" with the second command) - -2) Import the head revision from the given Perforce path into a git branch -called "p4" (remotes/p4 actually) - -3) Create a master branch based on it and check it out. - -If you want the entire history (not just the head revision) then you can simply -append a "@all" to the depot path: - - git-p4 clone //depot/project/main@all myproject - - - -If you want more control you can also use the git-p4 sync command directly: - - mkdir repo-git - cd repo-git - git init - git-p4 sync //path/in/your/perforce/depot - -This will import the current head revision of the specified depot path into a -"remotes/p4/master" branch of your git repository. You can use the ---branch=mybranch option to import into a different branch. - -If you want to import the entire history of a given depot path simply use: - - git-p4 sync //path/in/depot@all - - -Note: - -To achieve optimal compression you may want to run 'git repack -a -d -f' after -a big import. This may take a while. - -Incremental Imports -=================== - -After an initial import you can continue to synchronize your git repository -with newer changes from the Perforce depot by just calling - - git-p4 sync - -in your git repository. By default the "remotes/p4/master" branch is updated. - -Advanced Setup -============== - -Suppose you have a periodically updated git repository somewhere, containing a -complete import of a Perforce project. This repository can be cloned and used -with git-p4. When updating the cloned repository with the "sync" command, -git-p4 will try to fetch changes from the original repository first. The git -protocol used with this is usually faster than importing from Perforce -directly. - -This behaviour can be disabled by setting the "git-p4.syncFromOrigin" git -configuration variable to "false". - -Updating -======== - -A common working pattern is to fetch the latest changes from the Perforce depot -and merge them with local uncommitted changes. The recommended way is to use -git's rebase mechanism to preserve linear history. git-p4 provides a convenient - - git-p4 rebase - -command that calls git-p4 sync followed by git rebase to rebase the current -working branch. - -Submitting -========== - -git-p4 has support for submitting changes from a git repository back to the -Perforce depot. This requires a Perforce checkout separate from your git -repository. To submit all changes that are in the current git branch but not in -the "p4" branch (or "origin" if "p4" doesn't exist) simply call - - git-p4 submit - -in your git repository. If you want to submit changes in a specific branch that -is not your current git branch you can also pass that as an argument: - - git-p4 submit mytopicbranch - -You can override the reference branch with the --origin=mysourcebranch option. - -The Perforce changelists will be created with the user who ran git-p4. If you -use --preserve-user then git-p4 will attempt to create Perforce changelists -with the Perforce user corresponding to the git commit author. You need to -have sufficient permissions within Perforce, and the git users need to have -Perforce accounts. Permissions can be granted using 'p4 protect'. - -If a submit fails you may have to "p4 resolve" and submit manually. You can -continue importing the remaining changes with - - git-p4 submit --continue - -Example -======= - -# Clone a repository - git-p4 clone //depot/path/project -# Enter the newly cloned directory - cd project -# Do some work... - vi foo.h -# ... and commit locally to gi - git commit foo.h -# In the meantime somebody submitted changes to the Perforce depot. Rebase your latest -# changes against the latest changes in Perforce: - git-p4 rebase -# Submit your locally committed changes back to Perforce - git-p4 submit -# ... and synchronize with Perforce - git-p4 rebase - - -Configuration parameters -======================== - -git-p4.user ($P4USER) - -Allows you to specify the username to use to connect to the Perforce repository. - - git config [--global] git-p4.user public - -git-p4.password ($P4PASS) - -Allows you to specify the password to use to connect to the Perforce repository. -Warning this password will be visible on the command-line invocation of the p4 binary. - - git config [--global] git-p4.password public1234 - -git-p4.port ($P4PORT) - -Specify the port to be used to contact the Perforce server. As this will be passed -directly to the p4 binary, it may be in the format host:port as well. - - git config [--global] git-p4.port codes.zimbra.com:2666 - -git-p4.host ($P4HOST) - -Specify the host to contact for a Perforce repository. - - git config [--global] git-p4.host perforce.example.com - -git-p4.client ($P4CLIENT) - -Specify the client name to use - - git config [--global] git-p4.client public-view - -git-p4.allowSubmit - - git config [--global] git-p4.allowSubmit false - -git-p4.syncFromOrigin - -A useful setup may be that you have a periodically updated git repository -somewhere that contains a complete import of a Perforce project. That git -repository can be used to clone the working repository from and one would -import from Perforce directly after cloning using git-p4. If the connection to -the Perforce server is slow and the working repository hasn't been synced for a -while it may be desirable to fetch changes from the origin git repository using -the efficient git protocol. git-p4 supports this setup by calling "git fetch origin" -by default if there is an origin branch. You can disable this using: - - git config [--global] git-p4.syncFromOrigin false - -git-p4.useclientspec - - git config [--global] git-p4.useclientspec false - -The P4CLIENT environment variable should be correctly set for p4 to be -able to find the relevant client. This client spec will be used to -both filter the files cloned by git and set the directory layout as -specified in the client (this implies --keep-path style semantics). - -git-p4.skipSubmitEdit - - git config [--global] git-p4.skipSubmitEdit false - -Normally, git-p4 invokes an editor after each commit is applied so -that you can make changes to the submit message. Setting this -variable to true will skip the editing step, submitting the change as is. - -git-p4.skipSubmitEditCheck - - git config [--global] git-p4.skipSubmitEditCheck false - -After the editor is invoked, git-p4 normally makes sure you saved the -change description, as an indication that you did indeed read it over -and edit it. You can quit without saving to abort the submit (or skip -this change and continue). Setting this variable to true will cause -git-p4 not to check if you saved the change description. This variable -only matters if git-p4.skipSubmitEdit has not been set to true. - -git-p4.preserveUser - - git config [--global] git-p4.preserveUser false - -If true, attempt to preserve user names by modifying the p4 changelists. See -the "--preserve-user" submit option. - -git-p4.allowMissingPerforceUsers - - git config [--global] git-p4.allowMissingP4Users false - -If git-p4 is setting the perforce user for a commit (--preserve-user) then -if there is no perforce user corresponding to the git author, git-p4 will -stop. With allowMissingPerforceUsers set to true, git-p4 will use the -current user (i.e. the behavior without --preserve-user) and carry on with -the perforce commit. - -git-p4.skipUserNameCheck - - git config [--global] git-p4.skipUserNameCheck false - -When submitting, git-p4 checks that the git commits are authored by the current -p4 user, and warns if they are not. This disables the check. - -git-p4.detectRenames - -Detect renames when submitting changes to Perforce server. Will enable -M git -argument. Can be optionally set to a number representing the threshold -percentage value of the rename detection. - - git config [--global] git-p4.detectRenames true - git config [--global] git-p4.detectRenames 50 - -git-p4.detectCopies - -Detect copies when submitting changes to Perforce server. Will enable -C git -argument. Can be optionally set to a number representing the threshold -percentage value of the copy detection. - - git config [--global] git-p4.detectCopies true - git config [--global] git-p4.detectCopies 80 - -git-p4.detectCopiesHarder - -Detect copies even between files that did not change when submitting changes to -Perforce server. Will enable --find-copies-harder git argument. - - git config [--global] git-p4.detectCopies true - -git-p4.branchUser - -Only use branch specifications defined by the selected username. - - git config [--global] git-p4.branchUser username - -git-p4.branchList - -List of branches to be imported when branch detection is enabled. - - git config [--global] git-p4.branchList main:branchA - git config [--global] --add git-p4.branchList main:branchB - -Implementation Details... -========================= - -* Changesets from Perforce are imported using git fast-import. -* The import does not require anything from the Perforce client view as it just uses - "p4 print //depot/path/file#revision" to get the actual file contents. -* Every imported changeset has a special [git-p4...] line at the - end of the log message that gives information about the corresponding - Perforce change number and is also used by git-p4 itself to find out - where to continue importing when doing incremental imports. - Basically when syncing it extracts the perforce change number of the - latest commit in the "p4" branch and uses "p4 changes //depot/path/...@changenum,#head" - to find out which changes need to be imported. -* git-p4 submit uses "git rev-list" to pick the commits between the "p4" branch - and the current branch. - The commits themselves are applied using git diff/format-patch ... | git apply - -- 2.26.2