slapos/cache: Implement report command

Report allows to check which software releases are available on which
distribution in a binary cache.

setup.py

@@ -87,6 +87,7 @@ setup(name=name,
         'slapos.cli': [
           # Utilities
           'cache lookup = slapos.cli.cache:CacheLookupCommand',
+          'cache report = slapos.cli.cache:CacheReportCommand',
           'cache source = slapos.cli.cache_source:CacheLookupCommand',
           # SlapOS Node commands
           'node bang = slapos.cli.bang:BangCommand',

slapos/cli/cache.py

@@ -66,6 +66,26 @@ class CacheLookupCommand(ConfigCommand):
         sys.exit(
           do_lookup(self.app.log, cache_dir, args.software_url))
 
+class CacheReportCommand(ConfigCommand):
+    """
+    perform a report for given list of software relases against
+    given distribution
+    """
+
+    def get_parser(self, prog_name):
+        ap = super(CacheReportCommand, self).get_parser(prog_name)
+        ap.add_argument('--distribution',
+                        help='Distribution in a form <name> <version>, like debian 9')
+        ap.add_argument('software_url', nargs='+',
+                        help='Your software url or MD5 hash')
+        return ap
+
+    def take_action(self, args):
+        configp = self.fetch_config(args)
+        cache_dir = configp.get('networkcache', 'download-binary-dir-url')
+        sys.exit(
+          do_report(self.app.log, cache_dir, args.software_url, args.distribution))
+
 def looks_like_md5(s):
     """
     Return True if the parameter looks like an hashed value.
@@ -118,3 +138,50 @@ def do_lookup(logger, cache_dir, software_url):
         logger.info(line)
 
     return 0
+
+def do_report(logger, cache_dir, software_url_list, distribution):
+    if distribution:
+        linux_distribution = distribution.split()
+        linux_distribution.append('')
+    else:
+        linux_distribution = distribution_tuple()
+    for software_url in software_url_list:
+        status = ''
+        if looks_like_md5(software_url):
+            md5 = software_url
+        else:
+            md5 = hashlib.md5(str2bytes(software_url)).hexdigest()
+        try:
+            url = '%s/%s' % (cache_dir, md5)
+            logger.debug('Connecting to %s', url)
+            req = requests.get(url, timeout=5)
+        except (requests.Timeout, requests.ConnectionError):
+            msg = 'Cannot connect to cache server %s' % (url,)
+        else:
+            if not req.ok:
+                if req.status_code == 404:
+                    status = "not in cache"
+                else:
+                    status = "error while looking up"
+            else:
+                entries = req.json()
+
+                if not entries:
+                    status = "no binary in cache"
+
+            is_compatible = False
+            if status == '':
+                ostable = sorted(ast.literal_eval(json.loads(entry[0])['os']) for entry in entries)
+
+                meta = json.loads(entries[0][0])
+                for os in ostable:
+                    if networkcache.os_matches(os, linux_distribution):
+                        is_compatible = True
+                        break
+                if is_compatible:
+                    msg = "%r available for %r is compatible with %r." % (software_url, ' '.join(os[:3]).strip(), ' '.join(linux_distribution).strip(),)
+                else:
+                    msg = "%r compatible with %r NOT found." % (software_url, ' '.join(linux_distribution).strip(),)
+            else:
+                msg = "%r is NOT available because of %s" % (software_url, status)
+        logger.info(msg)

slapos/tests/test_cli.py

@@ -48,6 +48,7 @@ import slapos.cli.computer_token
 import slapos.cli.supervisorctl
 from slapos.cli.proxy_show import do_show, StringIO
 from slapos.cli.cache import do_lookup as cache_do_lookup
+from slapos.cli.cache import do_report
 from slapos.cli.cache_source import do_lookup as cache_source_do_lookup
 from slapos.client import ClientConfig
 import slapos.grid.svcbackend
@@ -105,6 +106,40 @@ class TestCliCache(CliMixin):
       'http://xxx.shacache.org/cccdc51a07e8c575c880f2d70dd4d458')
 
 
+class TestCliCacheReport(CliMixin):
+
+  test_url = "https://lab.nexedi.com/nexedi/slapos/raw/1.0.102/software/slaprunner/software.cfg"
+  def test_cached_binary(self):
+    do_report(
+        self.logger,
+        cache_dir="http://dir.shacache.org",
+        software_url_list=[self.test_url],
+        distribution='debian 8')
+
+    self.logger.info.assert_any_call(
+        "'https://lab.nexedi.com/nexedi/slapos/raw/1.0.102/software/slaprunner/software.cfg' available for 'debian 8.10' is compatible with 'debian 8'.")
+
+  def test_uncached_binary(self):
+    do_report(
+        self.logger,
+        cache_dir="http://dir.shacache.org",
+        software_url_list=["this_is_uncached_url"],
+        distribution='debian 8')
+
+    self.logger.info.assert_any_call(
+        "'this_is_uncached_url' is NOT available because of not in cache")
+
+  def test_bad_cache_dir(self):
+    do_report(
+        self.logger,
+        cache_dir="http://xxx.shacache.org",
+        software_url_list=[self.test_url],
+        distribution='debian 8')
+
+    self.logger.info.assert_any_call(
+        'Cannot connect to cache server http://xxx.shacache.org/cccdc51a07e8c575c880f2d70dd4d458')
+
+
 class TestCliCacheSource(CliMixin):
 
   test_url = "https://mirrors.edge.kernel.org/pub/software/scm/git/git-2.17.1.tar.xz"