Adding test case to test telemetry service "osversion/build" query. (#…

…2578)

Adding a new test case to validate the osversion/build telemetry query. This is a new query to get the Sonic build version from the telemetry service. Details of the changes on telemetry service can be found in this PR: sonic-net/sonic-telemetry#50

What is the motivation for this PR?
A test case needed to cover a recently added telemetry service feature.

How did you do it?
The test case runs the mentioned query and checks the existence of expected keywords in the response.

How did you verify/test it?
Using Sonic KVM testbed.

Co-authored-by: Murat <[email protected]>

tests/telemetry/test_telemetry.py

@@ -14,7 +14,16 @@
 logger = logging.getLogger(__name__)
 
 TELEMETRY_PORT = 50051
+METHOD_SUBSCRIBE = "subscribe"
+METHOD_GET = "get"
 
+SUBSCRIBE_MODE_STREAM = 0
+SUBSCRIBE_MODE_ONCE = 1
+SUBSCRIBE_MODE_POLL = 2
+
+SUBMODE_TARGET_DEFINED = 0
+SUBMODE_ON_CHANGE = 1
+SUBMODE_SAMPLE = 2
 
 # Helper functions
 def get_dict_stdout(gnmi_out, certs_out):
@@ -47,6 +56,21 @@ def setup_telemetry_forpyclient(duthost):
     else:
         logger.info('client auth is false. No need to restart telemetry')
 
+def generate_client_cli(duthost, method=METHOD_GET, xpath="COUNTERS/Ethernet0", target="COUNTERS_DB", subscribe_mode=SUBSCRIBE_MODE_STREAM, submode=SUBMODE_SAMPLE, intervalms=0, update_count=3):
+    """Generate the py_gnmicli command line based on the given params.
+    """
+    cmdFormat = 'python /gnxi/gnmi_cli_py/py_gnmicli.py -g -t {0} -p {1} -m {2} -x {3} -xt {4} -o {5}'
+    cmd = cmdFormat.format(duthost.mgmt_ip, TELEMETRY_PORT, method, xpath, target, "ndastreamingservertest")
+
+    if method == METHOD_SUBSCRIBE:
+        cmd += " --subscribe_mode {0} --submode {1} --interval {2} --update_count {3}".format(subscribe_mode, submode, intervalms, update_count)
+    return cmd
+
+def assert_equal(actual, expected, message):
+    """Helper method to compare an expected value vs the actual value.
+    """
+    pytest_assert(actual == expected, "{0}. Expected {1} vs actual {2}".format(message, expected, actual))
+
 @pytest.fixture(scope="module", autouse=True)
 def verify_telemetry_dockerimage(duthosts, rand_one_dut_hostname):
     """If telemetry docker is available in image then return true
@@ -138,6 +162,19 @@ def test_telemetry_ouput(duthosts, rand_one_dut_hostname, ptfhost, setup_streami
     inerrors_match = re.search("SAI_PORT_STAT_IF_IN_ERRORS", result)
     pytest_assert(inerrors_match is not None, "SAI_PORT_STAT_IF_IN_ERRORS not found in gnmi_output")
 
+def test_osbuild_version(duthosts, rand_one_dut_hostname, ptfhost, localhost):
+    """ Test osbuild/version query.
+    """
+    duthost = duthosts[rand_one_dut_hostname]
+    cmd = generate_client_cli(duthost=duthost, method=METHOD_GET, target="OTHERS", xpath="osversion/build")
+    logger.debug("Command to run: {0}".format(cmd))
+    show_gnmi_out = ptfhost.shell(cmd)['stdout']
+    logger.debug(show_gnmi_out)
+    result = str(show_gnmi_out)
+
+    assert_equal(len(re.findall('"build_version": "sonic\.', result)), 1, "build_version value at {0}".format(result))
+    assert_equal(len(re.findall('sonic\.NA', result, flags=re.IGNORECASE)), 0, "invalid build_version value at {0}".format(result))
+
 def test_sysuptime(duthosts, rand_one_dut_hostname, ptfhost, setup_streaming_telemetry, localhost):
     """
     @summary: Run pyclient from ptfdocker and test the dataset 'system uptime' to check