Tidying up a bit

clair_singularity/__init__.py

-VERSION='0.1.0'
+VERSION = '0.1.0'

clair_singularity/clair.py

 from __future__ import print_function
 import requests
-import json
 import sys
 
+from util import pretty_json, err_and_exit
+
 
 def check_clair(API_URI, quiet):
     """Check Clair is accessible by call to namespaces end point"""
@@ -15,8 +16,7 @@ def check_clair(API_URI, quiet):
         if not quiet:
             sys.stderr.write("Found Clair server with %d namespaces\n" % namespace_count)
     except Exception as e:
-        sys.stderr.write("Error - couldn't access Clair v1 API at %s\n%s\n" % (API_URI, e.message))
-        sys.exit(1)
+        err_and_exit("Error - couldn't access Clair v1 API at %s\n%s\n" % (API_URI, e.message), 1)
     return True
 
 
@@ -35,13 +35,10 @@ def post_layer(API_URI, image_name, image_uri, quiet):
             if not quiet:
                 sys.stderr.write("Image registered as layer with Clair\n")
         else:
-            pretty_response = json.dumps(r.json(), separators=(',', ':'), sort_keys=True, indent=2)
-            sys.stderr.write("Failed registering image with Clair\n %s\n" % pretty_response)
-            sys.exit(1)
+            err_and_exit("Failed registering image with Clair\n %s\n" % pretty_json(r), 1)
 
     except Exception as e:
-        sys.stderr.write("Error - couldn't send image to Clair - %s\n" % (e))
-        sys.exit(1)
+        err_and_exit("Error - couldn't send image to Clair - %s\n" % (e), 1)
 
 
 def get_report(API_URI, image_name):
@@ -53,13 +50,10 @@ def get_report(API_URI, image_name):
         if r.status_code == requests.codes.ok:
             return r.json()
         else:
-            pretty_response = json.dumps(r.json(), separators=(',', ':'), sort_keys=True, indent=2)
-            sys.stderr.write("Failed retrieving report from Clair\n %s\n" % pretty_response)
-            sys.exit(1)
+            err_and_exit("Failed retrieving report from Clair\n %s\n" % pretty_json(r), 1)
 
     except Exception as e:
-        sys.stderr.write("Error - couldn't retrieve report from Clair - %s\n" % (e))
-        sys.exit(1)
+        err_and_exit("Error - couldn't retrieve report from Clair - %s\n" % (e), 1)
 
 
 def format_report_text(report):

clair_singularity/cli.py

@@ -9,6 +9,7 @@ from .clair import check_clair, post_layer, get_report, format_report_text
 from .util import sha256
 from .image import check_image, image_to_tgz, http_server
 
+
 @click.command()
 @click.option('--clair-uri', default="http://localhost:6060",
               help='Base URI for your Clair server')

clair_singularity/image.py

@@ -3,16 +3,16 @@ import sys
 import tempfile
 from os import path, chdir
 
-import click
 from six.moves import SimpleHTTPServer, socketserver
 
+from .util import err_and_exit
+
 
 def check_image(image):
     """Check if specified image file exists"""
 
     if not path.isfile(image):
-        click.secho('Error: Singularity image "%s" not found.' % image, fg='red', err=True)
-        sys.exit(66)  # E_NOINPUT
+        err_and_exit('Error: Singularity image "%s" not found.' % image, 66)  # E_NOINPUT
     return True
 
 
@@ -31,8 +31,7 @@ def image_to_tgz(image, quiet):
     try:
         subprocess.check_call(cmd)
     except (subprocess.CalledProcessError, OSError) as e:
-        sys.stderr.write("Error calling Singularity export to create .tar file\n%s" % e.message)
-        sys.exit(1)
+        err_and_exit("Error calling Singularity export to create .tar file\n%s" % e.message, 1)
 
     cmd = ['gzip', tar_file]
 
@@ -42,8 +41,7 @@ def image_to_tgz(image, quiet):
     try:
         subprocess.check_call(cmd)
     except subprocess.CalledProcessError as e:
-        sys.stderr.write("Error calling gzip export to compress .tar file\n%s" % e.message)
-        sys.exit(1)
+        err_and_exit("Error calling gzip export to compress .tar file\n%s" % e.message, 1)
 
     return (temp_dir, tar_gz_file)
 

clair_singularity/util.py

 import hashlib
+import json
+import sys
 
 
 def sha256(fname):
+    """Compute sha256 hash for file fname"""
     hash_sha256 = hashlib.sha256()
     with open(fname, "rb") as f:
         for chunk in iter(lambda: f.read(65536), b""):
             hash_sha256.update(chunk)
     return hash_sha256.hexdigest()
+
+
+def pretty_json(obj):
+    """Format an object into json nicely"""
+    return json.dumps(obj.json(), separators=(',', ':'), sort_keys=True, indent=2)
+
+
+def err_and_exit(message, code=1):
+    """Write error to STDERR and exit with supplied code"""
+    sys.stderr.write(message)
+    sys.exit(code)

tests/test_cli.py

@@ -6,6 +6,7 @@ from clair_singularity.cli import cli
 
 from .test_image import testimage
 
+
 @pytest.fixture
 def runner():
     return CliRunner()
@@ -15,8 +16,11 @@ def test_help(runner):
     result = runner.invoke(cli, ['--help'])
     assert 'Usage:' in result.output
 
+
 def test_full_json(runner, testimage):
-    result = runner.invoke(cli, ['--quiet', '--json-output', '--bind-ip', '127.0.0.1', '--bind-port', '8081', '--clair-uri', 'http://127.0.0.1:6060', testimage])
+    result = runner.invoke(cli,
+                           ['--quiet', '--json-output', '--bind-ip', '127.0.0.1', '--bind-port', '8081', '--clair-uri',
+                            'http://127.0.0.1:6060', testimage])
     output = json.loads(result.output)
 
     # Using the shub://396 image and the 2017-08-21 clair db...
@@ -32,7 +36,8 @@ def test_full_json(runner, testimage):
 
 
 def test_full_text(runner, testimage):
-    result = runner.invoke(cli, ['--quiet', '--bind-ip', '127.0.0.1', '--bind-port', '8082', '--clair-uri', 'http://127.0.0.1:6060', testimage])
+    result = runner.invoke(cli, ['--quiet', '--bind-ip', '127.0.0.1', '--bind-port', '8082', '--clair-uri',
+                                 'http://127.0.0.1:6060', testimage])
     # Check we do have some CVEs we expect reported here
     assert 'bash - 4.3-14ubuntu1.1' in result.output
-    assert 'CVE-2016-9401' in result.output
\ No newline at end of file
+    assert 'CVE-2016-9401' in result.output