Add json formatting option to pip show

src/pip/_internal/commands/show.py

@@ -1,3 +1,4 @@
+import json
 import logging
 import os
 from email.parser import FeedParser
@@ -33,21 +34,41 @@ def add_options(self):
             action='store_true',
             default=False,
             help='Show the full list of installed files for each package.')
-
+        self.cmd_opts.add_option(
+            '--format',
+            action='store',
+            dest='list_format',
+            default="header",
+            choices=('header', 'json'),
+            help="Select the output format among: header (default) or json",
+        )
         self.parser.insert_option_group(0, self.cmd_opts)
 
     def run(self, options, args):
         # type: (Values, List[str]) -> int
         if not args:
             logger.warning('ERROR: Please provide a package name or names.')
             return ERROR
+
         query = args
 
+        # Get list of package infos and print them
         results = search_packages_info(query)
-        if not print_results(
-                results, list_files=options.files, verbose=options.verbose):
-            return ERROR
-        return SUCCESS
+        return_status = False
+
+        if options.list_format == 'header':
+
+            return_status = print_results_default(results,
+                                                  list_files=options.files,
+                                                  verbose=options.verbose)
+
+        elif options.list_format == 'json':
+
+            return_status = print_results_json(results,
+                                               list_files=options.files,
+                                               verbose=options.verbose)
+
+        return SUCCESS if return_status else ERROR
 
 
 def search_packages_info(query):
@@ -140,10 +161,10 @@ def get_requiring_packages(package_name):
         yield package
 
 
-def print_results(distributions, list_files=False, verbose=False):
+def print_results_default(distributions, list_files=False, verbose=False):
     # type: (Iterator[Dict[str, str]], bool, bool) -> bool
     """
-    Print the information from installed distributions found.
+    Print the information from installed distributions found in default format.
     """
     results_printed = False
     for i, dist in enumerate(distributions):
@@ -179,3 +200,52 @@ def print_results(distributions, list_files=False, verbose=False):
             if "files" not in dist:
                 write_output("Cannot locate installed-files.txt")
     return results_printed
+
+
+def print_results_json(distributions, list_files=False, verbose=False):
+    # type: (Iterator[Dict[str, Any]], bool, bool) -> bool
+    """
+    Build a dictionary with information from installed distributions
+        found in JSON format.
+    """
+
+    results_printed = False
+    pkg_infos_list = []
+
+    for dist in distributions:
+        results_printed = True
+        pkg_info = {}
+
+        pkg_info["name"] = dist.get('name', '')
+        pkg_info["version"] = dist.get('version', '')
+
+        pkg_info["summary"] = dist.get('summary', '')
+        pkg_info["home-page"] = dist.get('home-page', '')
+        pkg_info["author"] = dist.get('author', '')
+        pkg_info["author-email"] = dist.get('author-email', '')
+        pkg_info["license"] = dist.get('license', '')
+        pkg_info["location"] = dist.get('location', '')
+        pkg_info["requires"] = dist.get('requires', [])
+        pkg_info["required-by"] = dist.get('required_by', [])
+
+        if verbose:
+
+            pkg_info["metadata-version"] = dist.get('metadata-version', '')
+            pkg_info["installer"] = dist.get('installer', '')
+            pkg_info["classifiers"] = dist.get('classifiers', [])
+            pkg_info["entry-points"] = \
+                [entry.strip() for entry in dist.get('entry_points', [])]\
+                if 'entry_points' in dist else []
+
+        if list_files:
+            if "files" not in dist:
+                pkg_info["files"] = None
+            else:
+                pkg_info['files'] = [line.strip()
+                                     for line in dist.get('files', [])]
+
+        pkg_infos_list.append(pkg_info)
+
+    write_output(json.dumps(pkg_infos_list, ensure_ascii=False))
+
+    return results_printed

tests/functional/test_show.py

@@ -1,3 +1,4 @@
+import json
 import os
 import re
 
@@ -21,6 +22,18 @@ def test_basic_show(script):
     assert 'Requires: ' in lines
 
 
+def test_basic_show_json(script):
+    """
+    Test end to end test for show command.
+    """
+    result = script.pip('show', 'pip', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert len(data) == 10
+    assert data['name'] == 'pip'
+    assert data['version'] == '{}'.format(__version__)
+    assert {'location', 'requires'} <= set(data)
+
+
 def test_show_with_files_not_found(script, data):
     """
     Test for show command with installed files listing enabled and
@@ -39,6 +52,21 @@ def test_show_with_files_not_found(script, data):
     assert 'Cannot locate installed-files.txt' in lines
 
 
+def test_show_with_files_not_found_json(script, data):
+    """
+    Test for show command with installed files listing enabled and
+    installed-files.txt not found.
+    """
+    editable = data.packages.joinpath('SetupPyUTF8')
+    script.pip('install', '-e', editable)
+    result = script.pip('show', '-f', 'SetupPyUTF8', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert data['name'] == 'SetupPyUTF8'
+    assert data['version'] == '0.0.0'
+    assert {'location', 'requires'} <= set(data)
+    assert not data['files']
+
+
 def test_show_with_files_from_wheel(script, data):
     """
     Test that a wheel's files can be listed
@@ -52,6 +80,18 @@ def test_show_with_files_from_wheel(script, data):
     assert re.search(r"Files:\n(  .+\n)+", result.stdout)
 
 
+def test_show_with_files_from_wheel_json(script, data):
+    """
+    Test that a wheel's files can be listed
+    """
+    wheel_file = data.packages.joinpath('simple.dist-0.1-py2.py3-none-any.whl')
+    script.pip('install', '--no-index', wheel_file)
+    result = script.pip('show', '-f', 'simple.dist', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert data['name'] == 'simple.dist'
+    assert data['files']
+
+
 @pytest.mark.network
 def test_show_with_all_files(script):
     """
@@ -64,6 +104,17 @@ def test_show_with_all_files(script):
     assert re.search(r"Files:\n(  .+\n)+", result.stdout)
 
 
+@pytest.mark.network
+def test_show_with_all_files_json(script):
+    """
+    Test listing all files in the show command.
+    """
+    script.pip('install', 'initools==0.2')
+    result = script.pip('show', '--files', 'initools', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert data['files']
+
+
 def test_missing_argument(script):
     """
     Test show command with no arguments.
@@ -108,6 +159,21 @@ def test_report_mixed_not_found(script):
     assert 'Name: pip' in lines
 
 
+def test_report_mixed_not_found_json(script):
+    """
+    Test passing a mixture of found and not-found names.
+    """
+    # We test passing non-canonicalized names.
+    result = script.pip(
+        'show', 'Abcd3', 'A-B-C', 'pip', '--format=json',
+        allow_stderr_warning=True
+    )
+    assert 'WARNING: Package(s) not found: A-B-C, Abcd3' in result.stderr
+    print(result.stdout)
+    data = json.loads(result.stdout)[0]
+    assert data['name'] == 'pip'
+
+
 def test_search_any_case():
     """
     Search for a package in any case.
@@ -138,6 +204,17 @@ def test_show_verbose_with_classifiers(script):
     assert "Intended Audience :: Developers" in result.stdout
 
 
+def test_show_verbose_with_classifiers_json(script):
+    """
+    Test that classifiers can be listed
+    """
+    result = script.pip('show', 'pip', '--verbose', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert data['name'] == 'pip'
+    assert data['classifiers']
+    assert "Intended Audience :: Developers" in data["classifiers"]
+
+
 def test_show_verbose_installer(script, data):
     """
     Test that the installer is shown (this currently needs a wheel install)
@@ -150,6 +227,18 @@ def test_show_verbose_installer(script, data):
     assert 'Installer: pip' in lines
 
 
+def test_show_verbose_installer_json(script, data):
+    """
+    Test that the installer is shown (this currently needs a wheel install)
+    """
+    wheel_file = data.packages.joinpath('simple.dist-0.1-py2.py3-none-any.whl')
+    script.pip('install', '--no-index', wheel_file)
+    result = script.pip('show', '--verbose', 'simple.dist', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert data['name'] == 'simple.dist'
+    assert data['installer'] == 'pip'
+
+
 def test_show_verbose(script):
     """
     Test end to end test for verbose show command.
@@ -162,6 +251,17 @@ def test_show_verbose(script):
     assert 'Classifiers:' in lines
 
 
+def test_show_verbose_json(script):
+    """
+    Test end to end test for verbose show command.
+    """
+    result = script.pip('show', '--verbose', 'pip', '--format=json')
+    data = json.loads(result.stdout)[0]
+
+    assert {'metadata-version', 'installer',
+            'entry-points', 'classifiers'} <= set(data)
+
+
 def test_all_fields(script):
     """
     Test that all the fields are present
@@ -175,6 +275,18 @@ def test_all_fields(script):
     assert actual == expected
 
 
+def test_all_fields_json(script):
+    """
+    Test that all the fields are present
+    """
+    result = script.pip('show', 'pip', '--format=json')
+    data = json.loads(result.stdout)[0]
+    expected = {'name', 'version', 'summary', 'home-page', 'author',
+                'author-email', 'license', 'location', 'requires',
+                'required-by'}
+    assert set(data) == expected
+
+
 def test_pip_show_is_short(script):
     """
     Test that pip show stays short
@@ -184,6 +296,15 @@ def test_pip_show_is_short(script):
     assert len(lines) <= 10
 
 
+def test_pip_show_is_short_json(script):
+    """
+    Test that pip show stays short
+    """
+    result = script.pip('show', 'pip', '--format=json')
+    data = json.loads(result.stdout)[0]
+    assert len(data) <= 10
+
+
 def test_pip_show_divider(script, data):
     """
     Expect a divider between packages
@@ -222,6 +343,22 @@ def test_show_required_by_packages_basic(script, data):
     assert 'Required-by: requires-simple' in lines
 
 
+def test_show_required_by_packages_basic_json(script, data):
+    """
+    Test that installed packages that depend on this package are shown
+    """
+    editable_path = os.path.join(data.src, 'requires_simple')
+    script.pip(
+        'install', '--no-index', '-f', data.find_links, editable_path
+    )
+
+    result = script.pip('show', 'simple', '--format=json')
+    data = json.loads(result.stdout)[0]
+
+    assert data['name'] == 'simple'
+    assert data['required-by'] == ['requires-simple']
+
+
 def test_show_required_by_packages_capitalized(script, data):
     """
     Test that the installed packages which depend on a package are shown
@@ -239,6 +376,23 @@ def test_show_required_by_packages_capitalized(script, data):
     assert 'Required-by: Requires-Capitalized' in lines
 
 
+def test_show_required_by_packages_capitalized_json(script, data):
+    """
+    Test that the installed packages which depend on a package are shown
+    where the package has a capital letter
+    """
+    editable_path = os.path.join(data.src, 'requires_capitalized')
+    script.pip(
+        'install', '--no-index', '-f', data.find_links, editable_path
+    )
+
+    result = script.pip('show', 'simple', '--format=json')
+    data = json.loads(result.stdout)[0]
+
+    assert data['name'] == 'simple'
+    assert data['required-by'] == ['Requires-Capitalized']
+
+
 def test_show_required_by_packages_requiring_capitalized(script, data):
     """
     Test that the installed packages which depend on a package are shown
@@ -292,7 +446,6 @@ def test_show_include_work_dir_pkg(script):
                expect_stderr=True, cwd=pkg_path)
 
     script.environ.update({'PYTHONPATH': pkg_path})
-
     # Show should include package simple when run from package directory,
     # when package directory is in PYTHONPATH
     result = script.pip('show', 'simple', cwd=pkg_path)