[sonic-psud] add a new daemon sonic-psud to platform monitor (sonic-n…

…et#20)

* This new daemon will periodcally read PSU presence and status from sysfs and write to DB
* CLI will get the PSU presence and status from DB directly.

Signed-off-by: Kevin Wang <kevinw@mellanox.com>

sonic-psud/scripts/psud

@@ -0,0 +1,190 @@
+#!/usr/bin/env python2
+
+"""
+    Psud
+    PSU information update daemon for SONiC
+    This daemon will loop to collect PSU related information and then write the information to state DB.
+    Currently it is implemented based on old plugins rather than new platform APIs. So the PSU information just
+    includes three things: number of PSU, PSU presence and PSU status which is supported by old plugins.
+    The loop interval is PSU_INFO_UPDATE_PERIOD_SECS in seconds.
+"""
+
+try:
+    import getopt
+    import os
+    import imp
+    import signal
+    import subprocess
+    import sys
+    import syslog
+    import time
+    from swsscommon import swsscommon
+except ImportError, e:
+    raise ImportError (str(e) + " - required module not found")
+
+#============================= Constants =============================
+
+VERSION = '1.0'
+
+SYSLOG_IDENTIFIER = os.path.basename(__file__)
+PLATFORM_SPECIFIC_MODULE_NAME = "psuutil"
+PLATFORM_SPECIFIC_CLASS_NAME = "PsuUtil"
+
+# Platform root directory inside docker
+PLATFORM_ROOT_DOCKER = "/usr/share/sonic/platform"
+SONIC_CFGGEN_PATH = '/usr/local/bin/sonic-cfggen'
+HWSKU_KEY = 'DEVICE_METADATA.localhost.hwsku'
+PLATFORM_KEY = 'DEVICE_METADATA.localhost.platform'
+
+# Global platform-specific psuutil class instance
+platform_psuutil = None
+
+REDIS_HOSTNAME = "localhost"
+REDIS_PORT = 6379
+REDIS_TIMEOUT_MSECS = 0
+
+PSU_INFO_UPDATE_PERIOD_SECS = 3
+
+#========================== Syslog wrappers ==========================
+
+def log_info(msg, also_print_to_console=False):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_INFO, msg)
+    syslog.closelog()
+
+    if also_print_to_console:
+        print msg
+
+def log_warning(msg, also_print_to_console=False):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_WARNING, msg)
+    syslog.closelog()
+
+    if also_print_to_console:
+        print msg
+
+def log_error(msg, also_print_to_console=False):
+    syslog.openlog(SYSLOG_IDENTIFIER)
+    syslog.syslog(syslog.LOG_ERR, msg)
+    syslog.closelog()
+
+    if also_print_to_console:
+        print msg
+
+#========================== Signal Handling ==========================
+
+def signal_handler(sig, frame):
+    if sig == signal.SIGHUP:
+        log_info("Caught SIGHUP - ignoring...")
+        return
+    elif sig == signal.SIGINT:
+        log_info("Caught SIGINT - exiting...")
+        sys.exit(128 + sig)
+    elif sig == signal.SIGTERM:
+        log_info("Caught SIGTERM - exiting...")
+        sys.exit(128 + sig)
+    else:
+        log_warning("Caught unhandled signal '" + sig + "'")
+        return
+
+#============ Functions to load platform-specific classes ============
+
+# Returns platform and HW SKU
+def get_platform_and_hwsku():
+    try:
+        proc = subprocess.Popen([SONIC_CFGGEN_PATH, '-H', '-v', PLATFORM_KEY],
+                                stdout=subprocess.PIPE,
+                                shell=False,
+                                stderr=subprocess.STDOUT)
+        stdout = proc.communicate()[0]
+        proc.wait()
+        platform = stdout.rstrip('\n')
+
+        proc = subprocess.Popen([SONIC_CFGGEN_PATH, '-d', '-v', HWSKU_KEY],
+                                stdout=subprocess.PIPE,
+                                shell=False,
+                                stderr=subprocess.STDOUT)
+        stdout = proc.communicate()[0]
+        proc.wait()
+        hwsku = stdout.rstrip('\n')
+    except OSError, e:
+        raise OSError("Cannot detect platform")
+
+    return (platform, hwsku)
+
+# Loads platform specific psuutil module from source
+def load_platform_psuutil():
+    global platform_psuutil
+
+    # Get platform and hwsku
+    (platform, hwsku) = get_platform_and_hwsku()
+
+    # Load platform module from source
+    platform_path = PLATFORM_ROOT_DOCKER
+    hwsku_path = "/".join([platform_path, hwsku])
+
+    try:
+        module_file = "/".join([platform_path, "plugins", PLATFORM_SPECIFIC_MODULE_NAME + ".py"])
+        module = imp.load_source(PLATFORM_SPECIFIC_MODULE_NAME, module_file)
+    except IOError, e:
+        log_error("Failed to load platform module '%s': %s" % (PLATFORM_SPECIFIC_MODULE_NAME, str(e)), True)
+        return -1
+
+    try:
+        platform_psuutil_class = getattr(module, PLATFORM_SPECIFIC_CLASS_NAME)
+        platform_psuutil = platform_psuutil_class()
+    except AttributeError, e:
+        log_error("Failed to instantiate '%s' class: %s" % (PLATFORM_SPECIFIC_CLASS_NAME, str(e)), True)
+        return -2
+
+    return 0
+
+def psu_db_update(psu_tbl, num_psus):
+    for psu_index in range(1, num_psus + 1):
+        fvs = swsscommon.FieldValuePairs([('presence',
+                                           'true' if platform_psuutil.get_psu_presence(psu_index) else 'false'),
+                                          ('status',
+                                           'true' if platform_psuutil.get_psu_status(psu_index) else 'false')])
+        psu_tbl.set("PSU {}".format(psu_index), fvs)
+
+#=============================== Main ================================
+
+def main():
+    log_info("Starting up...")
+
+    # Register our signal handlers
+    signal.signal(signal.SIGHUP, signal_handler)
+    signal.signal(signal.SIGINT, signal_handler)
+    signal.signal(signal.SIGTERM, signal_handler)
+
+    # Load platform-specific psuutil class
+    err = load_platform_psuutil()
+    if err != 0:
+        log_error("failed to load psuutil")
+        sys.exit(1)
+
+    state_db = swsscommon.DBConnector(swsscommon.STATE_DB,
+                                      REDIS_HOSTNAME,
+                                      REDIS_PORT,
+                                      REDIS_TIMEOUT_MSECS)
+    psu_tbl = swsscommon.Table(state_db, "PSU_INFO")
+    chassis_tbl = swsscommon.Table(state_db, "CHASSIS_INFO")
+    num_psus = platform_psuutil.get_num_psus()
+    fvs = swsscommon.FieldValuePairs([('num_psus', str(num_psus))])
+    chassis_tbl.set('chassis 1', fvs)
+
+    # Start main loop to listen to the PSU change event.
+    log_info("Start main loop")
+    while True:
+        psu_db_update(psu_tbl, num_psus)
+        time.sleep(PSU_INFO_UPDATE_PERIOD_SECS)
+
+    # Clean all the information from DB and then exit
+    for psu_index in range(1, num_psus + 1):
+        psu_tbl._del("PSU {}".format(psu_index))
+    chassis_tbl._del('chassis 1')
+    log_error("Error: return error from psu daemon, exiting...")
+    return 1
+
+if __name__ == '__main__':
+    main()

sonic-psud/setup.py

@@ -0,0 +1,29 @@
+from setuptools import setup
+
+setup(
+    name='sonic-psud',
+    version='1.0',
+    description='PSU daemon for SONiC',
+    license='Apache 2.0',
+    author='SONiC Team',
+    author_email='linuxnetdev@microsoft.com',
+    url='https://github.com/Azure/sonic-platform-daemons',
+    maintainer='Kevin Wang',
+    maintainer_email='kevinw@mellanox.com',
+    scripts=[
+        'scripts/psud',
+    ],
+    classifiers=[
+        'Development Status :: 4 - Beta',
+        'Environment :: No Input/Output (Daemon)',
+        'Intended Audience :: Developers',
+        'Intended Audience :: Information Technology',
+        'Intended Audience :: System Administrators',
+        'License :: OSI Approved :: Apache Software License',
+        'Natural Language :: English',
+        'Operating System :: POSIX :: Linux',
+        'Programming Language :: Python :: 2.7',
+        'Topic :: System :: Hardware',
+    ],
+    keywords='sonic SONiC psu PSU daemon psud PSUD',
+)