From 7ec233f3bb0bd31de3e32883ac89ef6f72c36d1a Mon Sep 17 00:00:00 2001
From: Guilhem MARION <gmarion@netc.fr>
Date: Mon, 10 Oct 2022 07:48:14 +1030
Subject: [PATCH] Refactor reporting to provide instant feedback on default
 output

---
 certo/__main__.py        | 21 ++++++++--------
 certo/checks/hostname.py |  2 +-
 certo/output.py          | 34 --------------------------
 certo/report.py          | 53 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 65 insertions(+), 45 deletions(-)
 delete mode 100644 certo/output.py
 create mode 100644 certo/report.py

diff --git a/certo/__main__.py b/certo/__main__.py
index ff20d0e..e9cf8d5 100644
--- a/certo/__main__.py
+++ b/certo/__main__.py
@@ -12,7 +12,7 @@ import logging
 from docopt import docopt
 
 from certo.checks.hostname import check_host_certificate_expiration
-from certo.output import default_output, json_output
+from certo.report import JSONReporter, DefaultReporter
 
 if __name__ == "__main__":
     args = docopt(__doc__)
@@ -23,17 +23,18 @@ if __name__ == "__main__":
     hostnames = args.get("<hostnames>")
     days_to_expiration = int(args.get("--days-to-expiration"))
 
-    results = []
+    # @todo factory
+    if output_as_json:
+        reporter = JSONReporter()
+    else:
+        reporter = DefaultReporter()
 
+    # @todo async
     for hs in hostnames:
         logging.info(f"Getting CERT from {hs}")
-        results.append(check_host_certificate_expiration(hs, days_to_expiration))
+        reporter.add_check(check_host_certificate_expiration(hs, days_to_expiration))
 
-    failed = list(r for r in results if not r.check_successful)
+    if log := reporter.report():
+        print(log)
 
-    if output_as_json:
-        print(json_output(results))
-    else:
-        print(default_output(results))
-
-    exit(len(failed))
+    exit(reporter.num_failed())
diff --git a/certo/checks/hostname.py b/certo/checks/hostname.py
index da62b32..7f59bd4 100644
--- a/certo/checks/hostname.py
+++ b/certo/checks/hostname.py
@@ -34,7 +34,7 @@ def check_host_certificate_expiration(hostname, days_to_expiration, timeout=5):
             hostname,
             False,
             expdate,
-            f"Certificate expires in {(expdate - curdate).days} days - expected more than {days_to_expiration}",
+            f"Certificate expires in {(expdate - curdate).days} days, expected more than {days_to_expiration}",
         )
     return CertCheckResult(
         hostname,
diff --git a/certo/output.py b/certo/output.py
deleted file mode 100644
index a1c0395..0000000
--- a/certo/output.py
+++ /dev/null
@@ -1,34 +0,0 @@
-import json
-from typing import List
-
-from certo.checks.hostname import CertCheckResult
-
-
-def json_output(cert_check_results: List[CertCheckResult]):
-    def make_check_serialisable(check):
-        """
-        Converts a CertCheckResult for json serialisation
-        :param check: CertCheckResult as output by checks
-        :return: check as dict() with appropriate type conversions for json.dumps
-        """
-        ret = check._asdict()
-        if check.expiration_date:
-            ret["expiration_date"] = check.expiration_date.strftime("%c %Z")
-        return ret
-
-    return json.dumps(
-        list(map(lambda check: make_check_serialisable(check), cert_check_results)),
-        indent=4,
-    )
-
-
-def default_output(cert_check_results: List[CertCheckResult]):
-    res = list()
-    for check in cert_check_results:
-        result = f"[{'PASS' if check.check_successful else 'FAIL'}] Check host {check.hostname}"
-        if check.debug:
-            result += f" - {check.debug}"
-        if check.expiration_date:
-            result += f" - Certificate expires on {check.expiration_date} {check.expiration_date.tzname()}"
-        res.append(result)
-    return "\n".join(res)
diff --git a/certo/report.py b/certo/report.py
new file mode 100644
index 0000000..51387ee
--- /dev/null
+++ b/certo/report.py
@@ -0,0 +1,53 @@
+import json
+
+
+class CheckReporter:
+    def __init__(self):
+        self.checks = list()
+
+    def add_check(self, check):
+        self.checks.append(check)
+
+    def failed(self):
+        return list(r for r in self.checks if not r.check_successful)
+
+    def num_failed(self):
+        return len(self.failed())
+
+    def report(self):
+        ...
+
+
+class JSONReporter(CheckReporter):
+    def __make_check_serialisable(check):
+        """
+        Converts a CertCheckResult for json serialisation
+        :param check: CertCheckResult as output by checks
+        :return: check as dict() with appropriate type conversions for json.dumps
+        """
+        ret = check._asdict()
+        if check.expiration_date:
+            ret["expiration_date"] = check.expiration_date.strftime("%c %Z")
+        return ret
+
+    def report(self):
+        return json.dumps(
+            list(
+                map(
+                    lambda check: JSONReporter.__make_check_serialisable(check),
+                    self.checks,
+                )
+            ),
+            indent=4,
+        )
+
+
+class DefaultReporter(CheckReporter):
+    def add_check(self, check):
+        super().add_check(check)
+        result = f"[{'PASS' if check.check_successful else 'FAIL'}] Check host {check.hostname}"
+        if check.debug:
+            result += f" - {check.debug}"
+        if check.expiration_date:
+            result += f" - Certificate expires on {check.expiration_date} {check.expiration_date.tzname()}"
+        print(result)