#!/bin/bash
#
# **inc/python** - Python-related functions
#
# Support for pip/setuptools interfaces and virtual environments
#
# External functions used:
# - GetOSVersion
# - is_fedora
# - safe_chown

# Save trace setting
INC_PY_TRACE=$(set +o | grep xtrace)
set +o xtrace


# Global Config Variables

# PROJECT_VENV contains the name of the virtual environment for each
# project.  A null value installs to the system Python directories.
declare -A -g PROJECT_VENV

# Utility Functions
# =================

# Joins bash array of extras with commas as expected by other functions
function join_extras {
    local IFS=","
    echo "$*"
}

# Python Functions
# ================

# Setup the global devstack virtualenvs and the associated environment
# updates.
function setup_devstack_virtualenv {
    # We run devstack out of a global virtualenv.
    if [[ ! -d $DEVSTACK_VENV ]] ; then
        # Using system site packages to enable nova to use libguestfs.
        # This package is currently installed via the distro and not
        # available on pypi.
        python$PYTHON3_VERSION -m venv --system-site-packages $DEVSTACK_VENV
        pip_install -U pip
    fi
    if [[ ":$PATH:" != *":$DEVSTACK_VENV/bin:"* ]] ; then
        export PATH="$DEVSTACK_VENV/bin:$PATH"
        export PYTHON="$DEVSTACK_VENV/bin/python3"
    fi
}

# Get the path to the pip command.
# get_pip_command
function get_pip_command {
    local version="$1"
    if [ -z "$version" ]; then
        die $LINENO "pip python version is not set."
    fi

    # NOTE(dhellmann): I don't know if we actually get a pip3.4-python
    # under any circumstances.
    which pip${version} || which pip${version}-python

    if [ $? -ne 0 ]; then
        die $LINENO "Unable to find pip${version}; cannot continue"
    fi
}

# Get the path to the directory where python executables are installed.
# get_python_exec_prefix
function get_python_exec_prefix {
    local xtrace
    xtrace=$(set +o | grep xtrace)
    set +o xtrace
    if [[ -z "$os_PACKAGE" ]]; then
        GetOSVersion
    fi
    $xtrace

    if [[ "$GLOBAL_VENV" == "True" ]] ; then
        echo "$DEVSTACK_VENV/bin"
    else
        echo "/usr/local/bin"
    fi
}

# Wrapper for ``pip install`` that only installs versions of libraries
# from the global-requirements specification.
#
# Uses globals ``REQUIREMENTS_DIR``
#
# pip_install_gr packagename
function pip_install_gr {
    local name=$1
    local clean_name
    clean_name=$(get_from_global_requirements $name)
    pip_install $clean_name
}

# Wrapper for ``pip install`` that only installs versions of libraries
# from the global-requirements specification with extras.
#
# Uses globals ``REQUIREMENTS_DIR``
#
# pip_install_gr_extras packagename extra1,extra2,...
function pip_install_gr_extras {
    local name=$1
    local extras=$2
    local version_constraints
    version_constraints=$(get_version_constraints_from_global_requirements $name)
    pip_install $name[$extras]$version_constraints
}

# enable_python3_package() -- no-op for backwards compatibility
#
# enable_python3_package dir [dir ...]
function enable_python3_package {
    local xtrace
    xtrace=$(set +o | grep xtrace)
    set +o xtrace

    echo "It is no longer necessary to call enable_python3_package()."

    $xtrace
}

# disable_python3_package() -- no-op for backwards compatibility
#
# disable_python3_package dir [dir ...]
function disable_python3_package {
    local xtrace
    xtrace=$(set +o | grep xtrace)
    set +o xtrace

    echo "It is no longer possible to call disable_python3_package()."

    $xtrace
}

# Wrapper for ``pip install`` to set cache and proxy environment variables
# Uses globals ``OFFLINE``, ``PIP_VIRTUAL_ENV``,
# ``PIP_UPGRADE``, ``*_proxy``,
# Usage:
#  pip_install pip_arguments
function pip_install {
    local xtrace result
    xtrace=$(set +o | grep xtrace)
    set +o xtrace
    local upgrade=""
    local offline=${OFFLINE:-False}
    if [[ "$offline" == "True" || -z "$@" ]]; then
        $xtrace
        return
    fi

    time_start "pip_install"

    PIP_UPGRADE=$(trueorfalse False PIP_UPGRADE)
    if [[ "$PIP_UPGRADE" = "True" ]] ; then
        upgrade="--upgrade"
    fi

    if [[ -z "$os_PACKAGE" ]]; then
        GetOSVersion
    fi

    # Try to extract the path of the package we are installing into
    # package_dir.  We need this to check for test-requirements.txt,
    # at least.
    #
    # ${!#} expands to the last positional argument to this function.
    # With "extras" syntax included, our arguments might be something
    # like:
    #  -e /path/to/fooproject[extra]
    # Thus this magic line grabs just the path without extras
    #
    # Note that this makes no sense if this is a pypi (rather than
    # local path) install; ergo you must check this path exists before
    # use.  Also, if we had multiple or mixed installs, we would also
    # likely break.  But for historical reasons, it's basically only
    # the other wrapper functions in here calling this to install
    # local packages, and they do so with single call per install.  So
    # this works (for now...)
    local package_dir=${!#%\[*\]}

    if [[ -n ${PIP_VIRTUAL_ENV:=} && -d ${PIP_VIRTUAL_ENV} ]]; then
        local cmd_pip=$PIP_VIRTUAL_ENV/bin/pip
        local sudo_pip="env"
    elif [[ "${GLOBAL_VENV}" == "True" && -d ${DEVSTACK_VENV} ]] ; then
        # We have to check that the DEVSTACK_VENV exists because early
        # devstack boostrapping needs to operate in a system context
        # too bootstrap pip. Once pip is bootstrapped we create the
        # global venv and can start to use it.
        local cmd_pip=$DEVSTACK_VENV/bin/pip
        local sudo_pip="env"
        echo "Using python $PYTHON3_VERSION to install $package_dir"
    else
        local cmd_pip="python$PYTHON3_VERSION -m pip"
        # See
        #  https://github.com/pypa/setuptools/issues/2232
        #  http://lists.openstack.org/pipermail/openstack-discuss/2020-August/016905.html
        # this makes setuptools >=50 use the platform distutils.
        # We only want to do this on global pip installs, not if
        # installing in a virtualenv
        local sudo_pip="sudo -H LC_ALL=en_US.UTF-8 SETUPTOOLS_USE_DISTUTILS=stdlib "
        echo "Using python $PYTHON3_VERSION to install $package_dir"
    fi

    cmd_pip="$cmd_pip install"
    # Always apply constraints
    cmd_pip="$cmd_pip -c $REQUIREMENTS_DIR/upper-constraints.txt"

    $xtrace

    $sudo_pip \
        http_proxy="${http_proxy:-}" \
        https_proxy="${https_proxy:-}" \
        no_proxy="${no_proxy:-}" \
        PIP_FIND_LINKS=$PIP_FIND_LINKS \
        $cmd_pip $upgrade \
        $@
    result=$?

    time_stop "pip_install"
    return $result
}

function pip_uninstall {
    # Skip uninstall if offline
    [[ "${OFFLINE}" = "True" ]] && return

    local name=$1
    if [[ -n ${PIP_VIRTUAL_ENV:=} && -d ${PIP_VIRTUAL_ENV} ]]; then
        local cmd_pip=$PIP_VIRTUAL_ENV/bin/pip
        local sudo_pip="env"
    else
        local cmd_pip="python$PYTHON3_VERSION -m pip"
        local sudo_pip="sudo -H LC_ALL=en_US.UTF-8"
    fi
    # don't error if we can't uninstall, it might not be there
    $sudo_pip $cmd_pip uninstall -y $name || /bin/true
}

# get version of a package from global requirements file
# get_from_global_requirements <package>
function get_from_global_requirements {
    local package=$1
    local required_pkg
    required_pkg=$(grep -i -h ^${package} $REQUIREMENTS_DIR/global-requirements.txt | cut -d\# -f1)
    if [[ $required_pkg == ""  ]]; then
        die $LINENO "Can't find package $package in requirements"
    fi
    echo $required_pkg
}

# get only version constraints of a package from global requirements file
# get_version_constraints_from_global_requirements <package>
function get_version_constraints_from_global_requirements {
    local package=$1
    local required_pkg_version_constraint
    # drop the package name from output (\K)
    required_pkg_version_constraint=$(grep -i -h -o -P "^${package}\K.*" $REQUIREMENTS_DIR/global-requirements.txt | cut -d\# -f1)
    if [[ $required_pkg_version_constraint == ""  ]]; then
        die $LINENO "Can't find package $package in requirements"
    fi
    echo $required_pkg_version_constraint
}

# should we use this library from their git repo, or should we let it
# get pulled in via pip dependencies.
function use_library_from_git {
    local name=$1
    local enabled=1
    [[ ${LIBS_FROM_GIT} = 'ALL' ]] || [[ ,${LIBS_FROM_GIT}, =~ ,${name}, ]] && enabled=0
    return $enabled
}

# determine if a package was installed from git
function lib_installed_from_git {
    local name=$1
    local safe_name
    safe_name=$(python -c "from pkg_resources import safe_name; \
        print(safe_name('${name}'))")
    # Note "pip freeze" doesn't always work here, because it tries to
    # be smart about finding the remote of the git repo the package
    # was installed from.  This doesn't work with zuul which clones
    # repos with no remote.
    #
    # The best option seems to be to use "pip list" which will tell
    # you the path an editable install was installed from; for example
    # in response to something like
    #  pip install -e 'git+https://opendev.org/openstack/bashate#egg=bashate'
    # pip list --format columns shows
    #  bashate 0.5.2.dev19 /tmp/env/src/bashate
    # Thus we check the third column to see if we're installed from
    # some local place.
    [[ -n $(pip list --format=columns 2>/dev/null | awk "/^$safe_name/ {print \$3}") ]]
}

# setup a library by name. If we are trying to use the library from
# git, we'll do a git based install, otherwise we'll punt and the
# library should be installed by a requirements pull from another
# project.
function setup_lib {
    local name=$1
    local dir=${GITDIR[$name]}
    setup_install $dir
}

# setup a library by name in editable mode. If we are trying to use
# the library from git, we'll do a git based install, otherwise we'll
# punt and the library should be installed by a requirements pull from
# another project.
#
# use this for non namespaced libraries
#
# setup_dev_lib [-bindep] <name> [<extras>]
function setup_dev_lib {
    local bindep
    if [[ $1 == -bindep* ]]; then
        bindep="${1}"
        shift
    fi
    local name=$1
    local dir=${GITDIR[$name]}
    local extras=$2
    setup_develop $bindep $dir $extras
}

# this should be used if you want to install globally, all libraries should
# use this, especially *oslo* ones
#
# setup_install project_dir [extras]
# project_dir: directory of project repo (e.g., /opt/stack/keystone)
# extras: comma-separated list of optional dependencies to install
#         (e.g., ldap,memcache).
#         See https://docs.openstack.org/pbr/latest/user/using.html#extra-requirements
# bindep: Set "-bindep" as first argument to install bindep.txt packages
# The command is like "pip install <project_dir>[<extras>]"
function setup_install {
    local bindep
    if [[ $1 == -bindep* ]]; then
        bindep="${1}"
        shift
    fi
    local project_dir=$1
    local extras=$2
    _setup_package_with_constraints_edit $bindep $project_dir "" $extras
}

# this should be used for projects which run services, like all services
#
# setup_develop project_dir [extras]
# project_dir: directory of project repo (e.g., /opt/stack/keystone)
# extras: comma-separated list of optional dependencies to install
#         (e.g., ldap,memcache).
#         See https://docs.openstack.org/pbr/latest/user/using.html#extra-requirements
# The command is like "pip install -e <project_dir>[<extras>]"
function setup_develop {
    local bindep
    if [[ $1 == -bindep* ]]; then
        bindep="${1}"
        shift
    fi
    local project_dir=$1
    local extras=$2
    _setup_package_with_constraints_edit $bindep $project_dir -e $extras
}

# ``pip install -e`` the package, which processes the dependencies
# using pip before running `setup.py develop`
#
# Updates the constraints from REQUIREMENTS_DIR to reflect the
# future installed state of this package. This ensures when we
# install this package we get the from source version.
#
# Uses globals ``REQUIREMENTS_DIR``
# _setup_package_with_constraints_edit project_dir flags [extras]
# project_dir: directory of project repo (e.g., /opt/stack/keystone)
# flags: pip CLI options/flags
# extras: comma-separated list of optional dependencies to install
#         (e.g., ldap,memcache).
#         See https://docs.openstack.org/pbr/latest/user/using.html#extra-requirements
# The command is like "pip install <flags> <project_dir>[<extras>]"
function _setup_package_with_constraints_edit {
    local bindep
    if [[ $1 == -bindep* ]]; then
        bindep="${1}"
        shift
    fi
    local project_dir=$1
    local flags=$2
    local extras=$3

    # Normalize the directory name to avoid
    # "installation from path or url cannot be constrained to a version"
    # error.
    # REVISIT(yamamoto): Remove this when fixed in pip.
    # https://github.com/pypa/pip/pull/3582
    project_dir=$(cd $project_dir && pwd)

    if [ -n "$REQUIREMENTS_DIR" ]; then
        # Remove this package from constraints before we install it.
        # That way, later installs won't "downgrade" the install from
        # source we are about to do.
        local name
        name=$(awk '/^name.*=/ {print $3}' $project_dir/setup.cfg)
        if [ -z $name ]; then
            name=$(awk '/^name =/ {gsub(/"/, "", $3); print $3}' $project_dir/pyproject.toml)
        fi
        $REQUIREMENTS_DIR/.venv/bin/edit-constraints \
            $REQUIREMENTS_DIR/upper-constraints.txt -- $name
    fi

    setup_package $bindep $project_dir "$flags" $extras

    # If this project is in LIBS_FROM_GIT, verify it was actually installed
    # correctly.  This helps catch errors caused by constraints mismatches.
    if use_library_from_git "$project_dir"; then
        if ! lib_installed_from_git "$project_dir"; then
            die $LINENO "The following LIBS_FROM_GIT was not installed correctly: $project_dir"
        fi
    fi
}

# ``pip install -e`` the package, which processes the dependencies
# using pip before running `setup.py develop`.  The command is like
# "pip install <flags> <project_dir>[<extras>]"
#
# Uses globals ``STACK_USER``
#
# Usage:
#  setup_package [-bindep[=profile,profile]] <project_dir> <flags> [extras]
#
# -bindep     : Use bindep to install dependencies; select extra profiles
#               as comma separated arguments after "="
# project_dir : directory of project repo (e.g., /opt/stack/keystone)
# flags       : pip CLI options/flags
# extras      : comma-separated list of optional dependencies to install
#               (e.g., ldap,memcache).
#               See https://docs.openstack.org/pbr/latest/user/using.html#extra-requirements
function setup_package {
    local bindep=0
    local bindep_flag=""
    local bindep_profiles=""
    if [[ $1 == -bindep* ]]; then
        bindep=1
        IFS="=" read bindep_flag bindep_profiles <<< ${1}
        shift
    fi
    local project_dir=$1
    local flags=$2
    local extras=$3

    # if the flags variable exists, and it doesn't look like a flag,
    # assume it's actually the extras list.
    if [[ -n "$flags" && -z "$extras" && ! "$flags" =~ ^-.* ]]; then
        extras=$flags
        flags=""
    fi

    if [[ ! -z "$extras" ]]; then
        extras="[$extras]"
    fi

    # install any bindep packages
    if [[ $bindep == 1 ]]; then
        install_bindep $project_dir/bindep.txt $bindep_profiles
    fi

    pip_install $flags "$project_dir$extras"
    # ensure that further actions can do things like setup.py sdist
    if [[ "$flags" == "-e" && "$GLOBAL_VENV" == "False" ]]; then
        safe_chown -R $STACK_USER $1/*.egg-info
    fi
}

# Report whether python 3 should be used
# TODO(frickler): drop this once all legacy uses are removed
function python3_enabled {
    return 0
}

# Provide requested python version and sets PYTHON variable
function install_python {
    install_python3
    export PYTHON=$(which python${PYTHON3_VERSION} 2>/dev/null)
}

# Install python3 packages
function install_python3 {
    if is_ubuntu; then
        apt_get install python${PYTHON3_VERSION} python${PYTHON3_VERSION}-dev
    elif is_fedora; then
        if [ "$os_VENDOR" = "Fedora" ]; then
            install_package python${PYTHON3_VERSION//.}
        else
            install_package python${PYTHON3_VERSION//.} python${PYTHON3_VERSION//.}-devel
        fi
    fi
}

function install_devstack_tools {
    # intentionally old to ensure devstack-gate has control
    local dstools_version=${DSTOOLS_VERSION:-0.1.2}
    install_python3
    sudo pip3 install -U devstack-tools==${dstools_version}
}

# Restore xtrace
$INC_PY_TRACE

# Local variables:
# mode: shell-script
# End: