Add 'dotenv run' command for calling arbitrary shell script with .env (theskumar#105)

venthur · theskumar · commit b20d818c9296 · 2018-04-05T23:08:43.000+05:30
* Added support for calling arbitrary script with .env variables provides

* Integrated everything into cli.py

* Fail properly when no command given and exit with return code of command

* Updated README

* Added tests.

* Fixed test for run w/o command
diff --git a/README.md b/README.md
@@ -192,6 +192,7 @@ Options:
 Commands:
   get    Retrive the value for the given key.
   list   Display all the stored key/value.
+  run    Run command with environment variables from .env file present
   set    Store the given key/value.
   unset  Removes the given key.
 ```
diff --git a/dotenv/cli.py b/dotenv/cli.py
@@ -8,7 +8,7 @@
                      'Run pip install "python-dotenv[cli]" to fix this.')
     sys.exit(1)
 
-from .main import dotenv_values, get_key, set_key, unset_key
+from .main import dotenv_values, get_key, set_key, unset_key, run_command
 
 
 @click.group()
@@ -78,5 +78,19 @@ def unset(ctx, key):
         exit(1)
 
 
+@cli.command(context_settings={'ignore_unknown_options': True})
+@click.pass_context
+@click.argument('commandline', nargs=-1, type=click.UNPROCESSED)
+def run(ctx, commandline):
+    """Run command with environment variables present."""
+    file = ctx.obj['FILE']
+    dotenv_as_dict = dotenv_values(file)
+    if not commandline:
+        click.echo('No command given.')
+        exit(1)
+    ret = run_command(commandline, dotenv_as_dict)
+    exit(ret)
+
+
 if __name__ == "__main__":
     cli()
diff --git a/dotenv/main.py b/dotenv/main.py
@@ -7,6 +7,7 @@
 import os
 import re
 import sys
+from subprocess import Popen, PIPE, STDOUT
 import warnings
 from collections import OrderedDict
 
@@ -253,3 +254,46 @@ def load_dotenv(dotenv_path=None, stream=None, verbose=False, override=False):
 def dotenv_values(dotenv_path=None, stream=None, verbose=False):
     f = dotenv_path or stream or find_dotenv()
     return DotEnv(f, verbose=verbose).dict()
+
+
+def run_command(command, env):
+    """Run command in sub process.
+
+    Runs the command in a sub process with the variables from `env`
+    added in the current environment variables.
+
+    Parameters
+    ----------
+    command: List[str]
+        The command and it's parameters
+    env: Dict
+        The additional environment variables
+
+    Returns
+    -------
+    int
+        The return code of the command
+
+    """
+    # copy the current environment variables and add the vales from
+    # `env`
+    cmd_env = os.environ.copy()
+    cmd_env.update(env)
+
+    p = Popen(command,
+              stdin=PIPE,
+              stdout=PIPE,
+              stderr=STDOUT,
+              universal_newlines=True,
+              bufsize=0,
+              shell=False,
+              env=cmd_env)
+    try:
+        out, _ = p.communicate()
+        print(out)
+    except Exception:
+        warnings.warn('An error occured, running the command:')
+        out, _ = p.communicate()
+        warnings.warn(out)
+
+    return p.returncode
diff --git a/tests/test_cli.py b/tests/test_cli.py
@@ -192,3 +192,28 @@ def test_get_key_with_interpolation_of_unset_variable(cli):
         assert stored_value == 'BAR'
         del(environ['NOT_SET'])
         sh.rm(dotenv_path)
+
+
+def test_run(cli):
+    with cli.isolated_filesystem():
+        sh.touch(dotenv_path)
+        sh.cd(here)
+        dotenv.set_key(dotenv_path, 'FOO', 'BAR')
+        result = sh.dotenv('run', 'printenv', 'FOO').strip()
+        assert result == 'BAR'
+
+
+def test_run_with_other_env(cli, dotenv_file):
+    cli.invoke(dotenv_cli, ['--file', dotenv_file, 'set', 'FOO', "BAR"])
+    result = cli.invoke(dotenv_cli, ['--file', dotenv_file, 'run', 'printenv', 'FOO'])
+    assert result.output.strip() == 'BAR'
+
+
+def test_run_without_cmd(cli):
+    result = cli.invoke(dotenv_cli, ['run'])
+    assert result.exit_code != 0
+
+
+def test_run_with_invalid_cmd(cli):
+    result = cli.invoke(dotenv_cli, ['run', 'i_do_not_exist'])
+    assert result.exit_code != 0
