Add option to output failures only

certo/report.py

@@ -2,8 +2,9 @@ import json
 
 
 class CheckReporter:
-    def __init__(self):
+    def __init__(self, output_passes):
         self.checks = list()
+        self.output_passes = output_passes
 
     def append(self, check):
         self.checks.append(check)
@@ -35,7 +36,7 @@ class JSONReporter(CheckReporter):
             list(
                 map(
                     lambda check: JSONReporter.__make_check_serialisable(check),
-                    self.checks,
+                    self.checks if self.output_passes else self.failed(),
                 )
             ),
             indent=4,
@@ -45,6 +46,8 @@ class JSONReporter(CheckReporter):
 class DefaultReporter(CheckReporter):
     def append(self, check):
         super().append(check)
+        if check.check_successful and not self.output_passes:
+            return
         result = f"[{'PASS' if check.check_successful else 'FAIL'}] Check host {check.hostname}"
         if check.debug:
             result += f" - {check.debug}"