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pip install

Contents

Usage

.. pip-command-usage:: install

Description

.. pip-command-description:: install

Requirements File Format

Each line of the requirements file indicates something to be installed, and like arguments to :ref:`pip install`, the following forms are supported:

<requirement specifier>
<requirement specifier> [--install-options="..."] [--global-options="..."]
<archive url/path>
[-e] <local project path>
[-e] <vcs project url>

Since version 6.0, pip also supports markers using the "; " separator. Examples:

futures; python_version < '2.7'
http://my.package.repo/SomePackage-1.0.4.zip; python_version >= '3.4'

See the :ref:`pip install Examples<pip install Examples>` for examples of all these forms.

A line that begins with # is treated as a comment and ignored. Whitespace followed by a # causes the # and the remainder of the line to be treated as a comment.

A line ending in an unescaped \ is treated as a line continuation and the newline following it is effectively ignored.

Additionally, the following Package Index Options are supported:

For example, to specify :ref:`--no-index <--no-index>` and 2 :ref:`--find-links <--find-links>` locations:

--no-index
--find-links /my/local/archives
--find-links http://some.archives.com/archives

Lastly, if you wish, you can refer to other requirements files, like this:

-r more_requirements.txt

Requirement Specifiers

pip supports installing from "requirement specifiers" as implemented in pkg_resources Requirements

Some Examples:

'FooProject >= 1.2'
Fizzy [foo, bar]
'PickyThing<1.6,>1.9,!=1.9.6,<2.0a0,==2.4c1'
SomethingWhoseVersionIDontCareAbout

Note

Use single or double quotes around specifiers when using them in a shell to avoid > and < being interpreted as shell redirects. e.g. pip install 'FooProject>=1.2'. Don't use single or double quotes in a requirements.txt file.

Per-requirement Overrides

It is possible to set --install-options and --global-options for each requirement in the requirements file:

FooProject >= 1.2 --install-options="--prefix='/usr/local'" \
                  --global-options="--no-user-cfg"

The above translates roughly into running FooProject's setup.py script as:

python setup.py --no-user-cfg install --prefix='/usr/local'

Pre-release Versions

Starting with v1.4, pip will only install stable versions as specified by PEP426 by default. If a version cannot be parsed as a compliant PEP426 version then it is assumed to be a pre-release.

If a Requirement specifier includes a pre-release or development version (e.g. >=0.0.dev0) then pip will allow pre-release and development versions for that requirement. This does not include the != flag.

The pip install command also supports a :ref:`--pre <install_--pre>` flag that will enable installing pre-releases and development releases.

Externally Hosted Files

Starting with v1.4, pip will warn about installing any file that does not come from the primary index. As of version 1.5, pip defaults to ignoring these files unless asked to consider them.

The pip install command supports a :ref:`--allow-external PROJECT <--allow-external>` option that will enable installing links that are linked directly from the simple index but to an external host that also have a supported hash fragment. Externally hosted files for all projects may be enabled using the :ref:`--allow-all-external <--allow-all-external>` flag to the pip install command.

The pip install command also supports a :ref:`--allow-unverified PROJECT <--allow-unverified>` option that will enable installing insecurely linked files. These are either directly linked (as above) files without a hash, or files that are linked from either the home page or the download url of a package.

These options can be used in a requirements file. Assuming some fictional ExternalPackage that is hosted external and unverified, then your requirements file would be like so:

--allow-external ExternalPackage
--allow-unverified ExternalPackage
ExternalPackage

VCS Support

pip supports installing from Git, Mercurial, Subversion and Bazaar, and detects the type of VCS using url prefixes: "git+", "hg+", "bzr+", "svn+".

pip requires a working VCS command on your path: git, hg, svn, or bzr.

VCS projects can be installed in :ref:`editable mode <editable-installs>` (using the :ref:`--editable <install_--editable>` option) or not.

  • For editable installs, the clone location by default is "<venv path>/src/SomeProject" in virtual environments, and "<cwd>/src/SomeProject" for global installs. The :ref:`--src <install_--src>` option can be used to modify this location.
  • For non-editable installs, the project is built locally in a temp dir and then installed normally.

The "project name" component of the url suffix "egg=<project name>-<version>" is used by pip in its dependency logic to identify the project prior to pip downloading and analyzing the metadata. The optional "version" component of the egg name is not functionally important. It merely provides a human-readable clue as to what version is in use.

Git

pip currently supports cloning over git, git+https and git+ssh:

Here are the supported forms:

[-e] git+git://git.myproject.org/MyProject#egg=MyProject
[-e] git+https://git.myproject.org/MyProject#egg=MyProject
[-e] git+ssh://git.myproject.org/MyProject#egg=MyProject
-e git+git@git.myproject.org:MyProject#egg=MyProject

Passing branch names, a commit hash or a tag name is possible like so:

[-e] git://git.myproject.org/MyProject.git@master#egg=MyProject
[-e] git://git.myproject.org/MyProject.git@v1.0#egg=MyProject
[-e] git://git.myproject.org/MyProject.git@da39a3ee5e6b4b0d3255bfef95601890afd80709#egg=MyProject

Mercurial

The supported schemes are: hg+http, hg+https, hg+static-http and hg+ssh.

Here are the supported forms:

[-e] hg+http://hg.myproject.org/MyProject#egg=MyProject
[-e] hg+https://hg.myproject.org/MyProject#egg=MyProject
[-e] hg+ssh://hg.myproject.org/MyProject#egg=MyProject

You can also specify a revision number, a revision hash, a tag name or a local branch name like so:

[-e] hg+http://hg.myproject.org/MyProject@da39a3ee5e6b#egg=MyProject
[-e] hg+http://hg.myproject.org/MyProject@2019#egg=MyProject
[-e] hg+http://hg.myproject.org/MyProject@v1.0#egg=MyProject
[-e] hg+http://hg.myproject.org/MyProject@special_feature#egg=MyProject

Subversion

pip supports the URL schemes svn, svn+svn, svn+http, svn+https, svn+ssh.

You can also give specific revisions to an SVN URL, like so:

[-e] svn+svn://svn.myproject.org/svn/MyProject#egg=MyProject
[-e] svn+http://svn.myproject.org/svn/MyProject/trunk@2019#egg=MyProject

which will check out revision 2019. @{20080101} would also check out the revision from 2008-01-01. You can only check out specific revisions using -e svn+....

Bazaar

pip supports Bazaar using the bzr+http, bzr+https, bzr+ssh, bzr+sftp, bzr+ftp and bzr+lp schemes.

Here are the supported forms:

[-e] bzr+http://bzr.myproject.org/MyProject/trunk#egg=MyProject
[-e] bzr+sftp://user@myproject.org/MyProject/trunk#egg=MyProject
[-e] bzr+ssh://user@myproject.org/MyProject/trunk#egg=MyProject
[-e] bzr+ftp://user@myproject.org/MyProject/trunk#egg=MyProject
[-e] bzr+lp:MyProject#egg=MyProject

Tags or revisions can be installed like so:

[-e] bzr+https://bzr.myproject.org/MyProject/trunk@2019#egg=MyProject
[-e] bzr+http://bzr.myproject.org/MyProject/trunk@v1.0#egg=MyProject

Finding Packages

pip searches for packages on PyPI using the http simple interface, which is documented here and there

pip offers a number of Package Index Options for modifying how packages are found.

See the :ref:`pip install Examples<pip install Examples>`.

SSL Certificate Verification

Starting with v1.3, pip provides SSL certificate verification over https, for the purpose of providing secure, certified downloads from PyPI.

Caching

Starting with v6.0, pip provides an on by default cache which functions similarly to that of a web browser. While the cache is on by default and is designed do the right thing by default you can disable the cache and always access PyPI by utilizing the --no-cache-dir option.

When making any HTTP request pip will first check it's local cache to determine if it has a suitable response stored for that request which has not expired. If it does then it simply returns that response and doesn't make the request.

If it has a response stored, but it has expired, then it will attempt to make a conditional request to refresh the cache which will either return an empty response telling pip to simply use the cached item (and refresh the expiration timer) or it will return a whole new response which pip can then store in the cache.

When storing items in the cache pip will respect the CacheControl header if it exists, or it will fall back to the Expires header if that exists. This allows pip to function as a browser would, and allows the index server to communicate to pip how long it is reasonable to cache any particular item.

While this cache attempts to minimize network activity, it does not prevent network access all together. If you want a fast/local install solution that circumvents accessing PyPI, see :ref:`Fast & Local Installs`.

The default location for the cache directory depends on the Operating System:

Unix
:file:`~/.cache/pip` and it respects the XDG_CACHE_HOME directory.
OS X
:file:`~/Library/Caches/pip`.
Windows
:file:`<CSIDL_LOCAL_APPDATA>\pip\Cache`

Hash Verification

PyPI provides md5 hashes in the hash fragment of package download urls.

pip supports checking this, as well as any of the guaranteed hashlib algorithms (sha1, sha224, sha384, sha256, sha512, md5).

The hash fragment is case sensitive (i.e. sha1 not SHA1).

This check is only intended to provide basic download corruption protection. It is not intended to provide security against tampering. For that, see :ref:`SSL Certificate Verification`

"Editable" Installs

"Editable" installs are fundamentally "setuptools develop mode" installs.

You can install local projects or VCS projects in "editable" mode:

$ pip install -e path/to/SomeProject
$ pip install -e git+http://repo/my_project.git#egg=SomeProject

(See the :ref:`VCS Support` section above for more information on VCS-related syntax.)

For local projects, the "SomeProject.egg-info" directory is created relative to the project path. This is one advantage over just using setup.py develop, which creates the "egg-info" directly relative the current working directory.

Controlling setup_requires

Setuptools offers the setup_requires setup() keyword for specifying dependencies that need to be present in order for the setup.py script to run. Internally, Setuptools uses easy_install to fulfill these dependencies.

pip has no way to control how these dependencies are located. None of the Package Index Options have an effect.

The solution is to configure a "system" or "personal" Distutils configuration file to manage the fulfillment.

For example, to have the dependency located at an alternate index, add this:

[easy_install]
index_url = https://my.index-mirror.com

To have the dependency located from a local directory and not crawl PyPI, add this:

[easy_install]
allow_hosts = ''
find_links = file:///path/to/local/archives

Build System Interface

In order for pip to install a package from source, setup.py must implement the following commands:

setup.py egg_info [--egg-base XXX]
setup.py install --record XXX [--single-version-externally-managed] [--root XXX] [--compile|--no-compile] [--install-headers XXX]

The egg_info command should create egg metadata for the package, as described in the setuptools documentation at http://pythonhosted.org/setuptools/setuptools.html#egg-info-create-egg-metadata-and-set-build-tags

The install command should implement the complete process of installing the package to the target directory XXX.

To install a package in "editable" mode (pip install -e), setup.py must implement the following command:

setup.py develop --no-deps

This should implement the complete process of installing the package in "editable" mode.

One further setup.py command is invoked by pip install:

setup.py clean

This command is invoked to clean up temporary commands from the build. (TODO: Investigate in more detail when this command is required).

No other build system commands are invoked by the pip install command.

Installing a package from a wheel does not invoke the build system at all.

Options

.. pip-command-options:: install


.. pip-index-options::

Examples

  1. Install SomePackage and its dependencies from PyPI using :ref:`Requirement Specifiers`
$ pip install SomePackage            # latest version
$ pip install SomePackage==1.0.4     # specific version
$ pip install 'SomePackage>=1.0.4'     # minimum version
  1. Install a list of requirements specified in a file. See the :ref:`Requirements files <Requirements Files>`.
$ pip install -r requirements.txt
  1. Upgrade an already installed SomePackage to the latest from PyPI.
$ pip install --upgrade SomePackage
  1. Install a local project in "editable" mode. See the section on :ref:`Editable Installs <editable-installs>`.
$ pip install -e .                     # project in current directory
$ pip install -e path/to/project       # project in another directory
  1. Install a project from VCS in "editable" mode. See the sections on :ref:`VCS Support <VCS Support>` and :ref:`Editable Installs <editable-installs>`.
$ pip install -e git+https://git.repo/some_pkg.git#egg=SomePackage          # from git
$ pip install -e hg+https://hg.repo/some_pkg.git#egg=SomePackage            # from mercurial
$ pip install -e svn+svn://svn.repo/some_pkg/trunk/#egg=SomePackage         # from svn
$ pip install -e git+https://git.repo/some_pkg.git@feature#egg=SomePackage  # from 'feature' branch
$ pip install -e git+https://git.repo/some_repo.git#egg=subdir&subdirectory=subdir_path # install a python package from a repo subdirectory
  1. Install a package with setuptools extras.
$ pip install SomePackage[PDF]
$ pip install SomePackage[PDF]==3.0
$ pip install -e .[PDF]==3.0  # editable project in current directory
  1. Install a particular source archive file.
$ pip install ./downloads/SomePackage-1.0.4.tar.gz
$ pip install http://my.package.repo/SomePackage-1.0.4.zip
  1. Install from alternative package repositories.

Install from a different index, and not PyPI

$ pip install --index-url http://my.package.repo/simple/ SomePackage

Search an additional index during install, in addition to PyPI

$ pip install --extra-index-url http://my.package.repo/simple SomePackage

Install from a local flat directory containing archives (and don't scan indexes):

$ pip install --no-index --find-links=file:///local/dir/ SomePackage
$ pip install --no-index --find-links=/local/dir/ SomePackage
$ pip install --no-index --find-links=relative/dir/ SomePackage
  1. Find pre-release and development versions, in addition to stable versions. By default, pip only finds stable versions.
$ pip install --pre SomePackage