Collect DB dump when test failed

tests/conftest.py

@@ -1357,3 +1357,39 @@ def get_reboot_cause(duthost):
     uptime_end = duthost.get_up_time()
     if not uptime_end == uptime_start:
         duthost.show_and_parse("show reboot-cause history")
+
+def collect_db_dump_on_duts(request, duthosts):
+    '''
+        When test failed, teardown of this fixture will dump all the DB and collect to the test servers
+    '''
+    if hasattr(request.node, 'rep_call') and request.node.rep_call.failed:
+        dut_file_path = "/tmp/db_dump"
+        docker_file_path = "./logs/db_dump"
+        db_dump_path = os.path.join(dut_file_path, request.module.__name__, request.node.name)
+        db_dump_tarfile = "{}.tar.gz".format(dut_file_path)
+
+        # Collect DB config
+        dbs = set()
+        result = duthosts[0].shell("cat /var/run/redis/sonic-db/database_config.json")
+        db_config = json.loads(result['stdout'])
+        for db in db_config['DATABASES']:
+            db_id = db_config['DATABASES'][db]['id']
+            dbs.add(db_id)
+
+        # Collect DB dump
+        duthosts.file(path = db_dump_path, state="directory")
+        for i in dbs:
+            duthosts.shell("redis-dump -d {} -y -o {}/{}".format(i, db_dump_path, i))
+        duthosts.shell("tar czf {} {}".format(db_dump_tarfile, dut_file_path))
+        duthosts.fetch(src = db_dump_tarfile, dest = docker_file_path)
+
+        #remove dump file from dut
+        duthosts.shell("rm -rf {} {}".format(dut_file_path, db_dump_tarfile))
+
+@pytest.fixture(autouse=True)
+def collect_db_dump(request, duthosts):
+    '''
+        When test failed, teardown of this fixture will dump all the DB and collect to the test servers
+    '''
+    yield
+    collect_db_dump_on_duts(request, duthosts)