add tests and ci workflow for running tests

This commit adds tests (using python3 pytest framework):
1. Test basic accel-cmd commands (show version, show stat, etc)
2. Test ipoe shared session up (dhcpv4) without radius
3. Test pppoe discovery (without PADO delay)
4. Test pppoe discovery (without PADO delay)
5. Test pppoe session up (ipv4) without radius
6. Test vlan creation using vlan-mon (pppoe)

These tests require external utils. Please read tests/README.md how to setup
environment, how to run the tests and how to generate coverage report
Also, run-tests.yml contains step-by-step instruction how to run the tests

Signed-off-by: Sergey V. Lobanov <sergey@lobanov.in>

1 files changed, 86 insertions, 0 deletions

diff --git a/tests/common/accel_pppd_process.py b/tests/common/accel_pppd_process.py
new file mode 100644
index 00000000..c2ee451e
--- /dev/null
+++ b/tests/common/accel_pppd_process.py
@@ -0,0 +1,86 @@
+from subprocess import Popen, PIPE
+from common import process
+from threading import Thread
+import time
+
+
+def accel_pppd_thread_func(accel_pppd_control):
+    process = accel_pppd_control["process"]
+    print("accel_pppd_thread_func: before communicate")
+    (out, err) = process.communicate()
+    print(
+        "accel_pppd_thread_func: after communicate out=" + str(out) + " err=" + str(err)
+    )
+    process.wait()
+    print("accel_pppd_thread_func: after wait")
+
+
+def start(accel_pppd, args, accel_cmd, max_wait_time):
+    print("accel_pppd_start: begin")
+    accel_pppd_process = Popen([accel_pppd] + args, stdout=PIPE, stderr=PIPE)
+    accel_pppd_control = {"process": accel_pppd_process}
+    accel_pppd_thread = Thread(
+        target=accel_pppd_thread_func,
+        args=[accel_pppd_control],
+    )
+    accel_pppd_thread.start()
+
+    # wait until accel-pppd replies to 'show version'
+    # accel-pppd needs some time to be accessible
+    sleep_time = 0.0
+    is_started = False
+    while sleep_time < max_wait_time:
+        if accel_pppd_process.poll() is not None:  # process is terminated
+            print(
+                "accel_pppd_start: terminated during 'show version' polling in (sec): "
+                + str(sleep_time)
+            )
+            is_started = False
+            break
+        (exit, out, err) = process.run([accel_cmd, "show version"])
+        if exit != 0:  # does not reply
+            time.sleep(0.1)
+            sleep_time += 0.1
+        else:  # replied
+            print("accel_pppd_start: 'show version' replied")
+            is_started = True
+            break
+
+    return (is_started, accel_pppd_thread, accel_pppd_control)
+
+
+def end(accel_pppd_thread, accel_pppd_control, accel_cmd, max_wait_time):
+    print("accel_pppd_end: begin")
+    if accel_pppd_control["process"].poll() is not None: # terminated
+        print("accel_pppd_end: already terminated. nothing to do")
+        accel_pppd_thread.join() 
+        return
+
+    process.run(
+        [accel_cmd, "shutdown hard"]
+    )  # send shutdown hard command (in coverage mode it helps saving coverage data)
+    print("accel_pppd_end: after shutdown hard")
+
+    # wait until accel-pppd is finished
+    sleep_time = 0.0
+    is_finished = False
+    while sleep_time < max_wait_time:
+        if accel_pppd_control["process"].poll() is None:  # not terminated yet
+            time.sleep(0.01)
+            sleep_time += 0.01
+            # print("accel_pppd_end: sleep 0.01")
+        else:
+            is_finished = True
+            print(
+                "accel_pppd_end: finished via shutdown hard in (sec): "
+                + str(sleep_time)
+            )
+            break
+
+    # accel-pppd is still alive. kill it
+    if not is_finished:
+        print("accel_pppd_end: kill process: " + str(accel_pppd_control["process"]))
+        accel_pppd_control["process"].kill()  # kill -9 if 'shutdown hard' didn't help
+
+    accel_pppd_thread.join()  # wait until thread is finished
+    print("accel_pppd_end: end")