Package: collective.recipe.environment
ContentsOverviewExample usage: Use an environment variableExample usage: Set an environment variableSimilar recipesRegression test: Values containing variable substitution syntax breaks thingsChangelog1.1.0 (2017-07-27)1.0.0 (2017-07-20)0.2.0 (2012-08-21)0.1b1 (2011-08-18)ContentsOverviewExample usage: Use an environment variableExample usage: Set an environment variableSimilar recipesRegression test: Values containing variable substitution syntax breaks thingsChangelog1.1.0 (2017-07-27)1.0.0 (2017-07-20)0.2.0 (2012-08-21)0.1b1 (2011-08-18)OverviewThis recipe allows to set and get environment variables during the execution of a buildout.The recipe mirrors the current environment variables into its section, so that e.g.${environment:USER}will give the current user.To set an environment variable you just set it in the section.The environment variables are set and get during the initialization of theRecipeinstance,
i.e. afterbuildout.cfgis read but before any recipe is installed or updated.Example usage: Use an environment variableWe’ll start by creating a buildout that uses the recipe:>>> write('buildout.cfg',
... """
... [buildout]
... parts = environment print
...
... [some-section]
... some-option = ${environment:SOME_VARIABLE}
...
... [environment]
... recipe = collective.recipe.environment
...
... [print]
... recipe = mr.scripty
... install =
...     ... print(self.buildout['some-section']['some-option'])
...     ... return []
... """)Themr.scriptyrecipe is used to print out the value of the ${some-section:some-option}
option.Now we set the environment variable:>>> import os
>>> os.environ['SOME_VARIABLE'] = 'some_value'Running the buildout gives us:>>> run_buildout()
START...
some_value
...ENDExample usage: Set an environment variableWe’ll start by creating a buildout that uses the recipe:>>> write('buildout.cfg',
... """
... [buildout]
... parts = environment print
...
... [some-section]
... some-option = value2
...
... [environment]
... recipe = collective.recipe.environment
... var1 = value1
... var2 = ${some-section:some-option}
...
... [print]
... recipe = mr.scripty
... install =
...     ... import os
...     ... for var in ('var1', 'var2'):
...     ...     print('%s = %s' % (var, os.environ[var]))
...     ... return []
... """)Themr.scriptyrecipe is used to print out the values of the environment variables.Running the buildout gives us:>>> run_buildout()
START...
var1 = value1
var2 = value2
...ENDSimilar recipesThe functionality to mirror the environment variables into the recipe’s section is largely copied
fromgocept.recipe.env.Regression test: Values containing variable substitution syntax breaks thingsProblem: if an environment variable value contains something looking like variable substitution
in Buildout syntax then things break. We fix this by escaping the variable substitutions using
two dollar signs. Eg.:${foo}becomes$${foo}.Let’s see if it works.Set environment variables:>>> os.environ['PROBLEM_VAR_1'] = '${foo}'
>>> os.environ['PROBLEM_VAR_2'] = '${foo:bar}'
>>> os.environ['PROBLEM_VAR_3'] = 'Contains ${foo} and also ${foo:bar}.'
>>> os.environ['LEGAL_VAR_1'] = '$foo'
>>> os.environ['LEGAL_VAR_2'] = '{foo}'Write a buildout using those variables:>>> write('buildout.cfg',
... """
... [buildout]
... parts = environment print
...
... [some-section]
... option-1 = ${environment:PROBLEM_VAR_1}
... option-2 = ${environment:PROBLEM_VAR_2}
... option-3 = ${environment:PROBLEM_VAR_3}
... option-4 = ${environment:LEGAL_VAR_1}
... option-5 = ${environment:LEGAL_VAR_2}
...
... [environment]
... recipe = collective.recipe.environment
...
... [print]
... recipe = mr.scripty
... install =
...     ... section = self.buildout['some-section']
...     ... for (k, v) in sorted(section.items()):
...     ...     print('{} = {}'.format(k, v))
...     ... return []
...
... """)Running the buildout gives us:>>> run_buildout()
START...
option-1 = $${foo}
option-2 = $${foo:bar}
option-3 = Contains $${foo} and also $${foo:bar}.
option-4 = $foo
option-5 = {foo}
...ENDChangelog1.1.0 (2017-07-27)New features:Fix code for Python 3 compatiblity.
[cas–]1.0.0 (2017-07-20)Breaking changes:Fix bug: Values containing variable substitution syntax breaks things. This is a breaking change
because problematic values are escaped, eg. “${foo}” becomes “$${foo}”.0.2.0 (2012-08-21)Now it’s possible to read environment variables.0.1b1 (2011-08-18)First release.