Custom virtual environment

See merge request nexedi/slapos!1188

component/macros/virtual-env.cfg

@@ -2,6 +2,8 @@
 extends =
 	../pygolang/buildout.cfg
 
+parts =
+
 [virtual-env-base]
 recipe = slapos.recipe.build
 name = ${:_buildout_section_name_}
@@ -10,26 +12,26 @@ init =
   from zc.buildout.easy_install import working_set
   import os
   name = options['name']
-  eggs = options['eggs']
-  try:
-    scripts = "scripts = " + options['scripts']
-  except KeyError:
-    scripts = ""
+  eggs = options.get('eggs')
+  self.message = options.get('message')
+  self.chain = options.get('chain')
+  environment = options.get('environment')
+  scripts = options.get('scripts')
 
-  self.buildout.parse("""
+  eggs_template = """
   [.%(name)s.install-eggs]
   recipe = zc.recipe.egg
-  eggs = %(eggs)s
+  eggs =
+    %(eggs)s
   %(scripts)s
 
   [.%(name)s.install-interpreter]
   <= python-interpreter
-  eggs += %(eggs)s
-  """ % locals())
+  eggs +=
+    %(eggs)s
+  """
 
-  if is_true(options.get('default-instance')):
-    cookbook = "{slapos-cookbook:recipe}"
-    self.buildout.parse("""
+  instance_template = """
   [.%(name)s.instance]
   recipe = slapos.recipe.template
   output = ${buildout:directory}/instance.cfg
@@ -44,30 +46,99 @@ init =
     [publish]
     recipe = slapos.cookbook:publish
     activate-script = %(location)s
-    """ % locals())
+  """
+
+  if eggs:
+    self.buildout.parse(eggs_template % {
+      "eggs": "\n  ".join(e.strip() for e in eggs.splitlines()),
+      "name": name,
+      "scripts": "scripts = " + scripts if scripts else "",
+    })
+
+  if is_true(options.get('default-instance')):
+    self.buildout.parse(instance_template % {
+      "cookbook": "{slapos-cookbook:recipe}",
+      "location": location,
+      "name": name,
+    })
+
+  env = {
+    "PATH": self.buildout['buildout']['bin-directory'] + ":\$PATH",
+    "PS1": "\"(" + self.name + ") \$PS1\"",
+  }
+
+  if environment:
+    for line in environment.splitlines():
+      key, value = line.split("=", 1)
+      env[key.strip()] = value.strip()
+
+  self.env = env
 
 install =
+  message = ""
+  if self.message:
+    message = "echo " + "\n  echo ".join(
+      "%r" % line for line in self.message.splitlines())
+    message += "\n  echo \'\'"
+
+  chain = ""
+  if self.chain:
+    chain = "source " + "\n  source ".join(
+      "%r" % line for line in self.chain.splitlines())
+
   with open(location, "w") as f:
     f.write(options['template'] % {
-      "path" : self.buildout['buildout']['bin-directory'],
-      "name" : self.name,
+      "env": " ".join("%s %s" % (k, v) for k, v in self.env.items()),
+      "message": message,
+      "chain": chain,
     })
 
 # Template virtual env for bash shell in posix
 [virtual-env-base:posix]
 template =
+  if type deactivate > /dev/null 2>&1
+  then
+    export _OLD_PARAM=( "$@")
+    set %(env)s
+    while [ "$1" ]; do
+      if ! ( echo $_LIST_OLD_VENV | grep $1 ) > /dev/null 2>&1
+      then
+        eval "export _OLD_VENV_$1=\$$1"
+        eval "export _LIST_OLD_VENV=\"$1 \$_LIST_OLD_VENV\""
+      fi
+      eval "export $1=\"$2\""
+      shift
+      shift
+    done
+    if [[ -n "$_OLD_PARAM" ]]; then
+      set "$${_OLD_PARAM[@]}"
+    fi
+    unset _OLD_PARAM
+    %(chain)s
+    %(message)s
+  else
     deactivate () {
-    set PATH PS1
+      set $_LIST_OLD_VENV
       while [ "$1" ]; do
         eval "if [ \"\$_OLD_VENV_$1\" ]; then $1=\$_OLD_VENV_$1; else unset $1; fi; unset \$_OLD_VENV_$1"
         shift
       done
       unset -f deactivate
+      unset _LIST_OLD_VENV
     }
-
-
-  VENV_PATH=%(path)s
-  _OLD_VENV_PATH=$PATH
-  _OLD_VENV_PS1=$PS1
-  PATH=$VENV_PATH:$PATH
-  PS1='(%(name)s) '$PS1
+    export _OLD_PARAM=( "$@" )
+    set %(env)s
+    while [ "$1" ]; do
+      eval "_OLD_VENV_$1=\$$1"
+      eval "export $1=\"$2\""
+      eval "export _LIST_OLD_VENV=\"$1 \$_LIST_OLD_VENV\""
+      shift
+      shift
+    done
+    if [[ -n "$_OLD_PARAM" ]]; then
+      set "$${_OLD_PARAM[@]}"
+    fi
+    unset _OLD_PARAM
+    %(chain)s
+    %(message)s
+  fi

component/macros/virtual-env.rst

+Virtual environment
+===================
+
+Introduction
+------------
+
+The virtual environment macro allows you to quickly create a development environment.
+
+Options
+-------
+
+Several options are available to customize your virtual environment :
+
+name
+~~~~
+
+The ``name`` option is the name that will be displayed when the environment is activated. For example::
+
+  name = virtual-env
+
+gives::
+
+  >> source activate
+  ( virtual-env ) >>
+
+**Note:** By default, ``name`` is the name of the Buildout section that uses the macro.
+
+location
+~~~~~~~~
+
+The ``location`` option is where the script to be sourced will be stored. For example::
+
+  location = project/activate
+
+gives::
+
+  >> source project/activate
+  ( virtual-env ) >>
+  
+**Note:** Don't forget to add the name of the script in the path.
+
+eggs
+~~~~
+
+This option should not be used to install eggs during instantiation (in an instance file).
+
+It works the same way as ``zc.recipe.eggs``, you can add to the line several eggs to download for use in the virtual environment.
+
+A custom Python with the chosen eggs will then be generated. For example::
+
+  eggs = numpy
+
+gives::
+
+  ( virtual-env ) >> python
+  python
+  >>> import numpy
+
+scripts
+~~~~~~~
+
+This option should not be used to install scripts during instantiation (in an instance file).
+
+It works in the same way as in ``zc.recipe.eggs``, you can add to the line several scripts to generate for use in the virtual environment.For example::
+
+  eggs = Django
+  scripts = django-admin
+
+gives::
+
+  ( virtual-env ) >> django-admin
+
+**Note:** By default if the option is not used, all scripts will be installed.
+
+default-instance
+~~~~~~~~~~~~~~~~
+
+The ``default-instance`` option takes the value ``true`` or ``false``.
+
+If set to ``true``, it will create a minimal instance that will publish the path of the script to be sourced.
+
+If it is set to ``false``, you will be able to create your own custom instance.
+
+**Note:** If you want to use the macro in an ``instance`` file, you should set this option to ``false``.
+
+environment
+~~~~~~~~~~~
+
+The ``environment`` option allows you to choose the value of the environment variables of the virtual environment.
+
+They are to be written on the line in the form ``VAR = value``. For example::
+
+  environment = 
+    VAR1 = value1
+    VAR2 = value2
+
+gives::
+
+  ( virtual-env ) >> echo $VAR1
+  value1
+
+**Note:** If you want to keep the other values as well, like for PATH for example, you have to do::
+
+  PATH = new_val:$PATH
+
+message
+~~~~~~~
+
+The ``message`` option allows to display a message when sourcing the virtual environment.
+
+The message will be considered as a string. For example::
+
+  message =
+    You are in a virtual environment.
+
+gives::
+
+  >> source activate
+  You are in a virtual environment.
+
+  ( virtual-env) >> 
+
+chain
+~~~~~
+
+The ``chain`` option allows you to chain several scripts created by the macro as if it were one. This can be useful if one script is generated in a ``software`` file and another in an ``instance`` file.
+
+When deactivating, the state of the environment will return to the initial state.
+
+To use this option you just have to specify the script to source by running the script. For example::
+
+  chain = project/another_activate
+
+Deactivate
+----------
+
+Once you want to exit the virtual environment, you just have to run the ``deactivate`` function. Like::
+
+  ( virtual-env ) >> deactivate
+    >>