[containercfgd] Add containercfgd and syslog rate limit configuration support (#12489)

* [containercfgd] Add containercfgd and syslog rate limit configuration support

* Fix build issue

* Fix checker issue

* Fix review comment

* Fix review comment

* Update containercfgd.py

dockers/docker-base-bullseye/Dockerfile.j2

@@ -81,7 +81,7 @@ RUN pip3 install supervisor==4.2.1
 # Add support for supervisord to handle startup dependencies
 RUN pip3 install supervisord-dependent-startup==1.4.0
 
-RUN mkdir -p /etc/supervisor /var/log/supervisor
+RUN mkdir -p /var/log/supervisor /etc/supervisor/conf.d
 
 RUN apt-get -y purge   \
     exim4              \
@@ -104,10 +104,10 @@ RUN apt-get clean -y                     && \
     apt-get autoremove -y                && \
     rm -rf /var/lib/apt/lists/* /tmp/* ~/.cache
 
-COPY ["etc/rsyslog.conf", "/etc/rsyslog.conf"]
 COPY ["etc/rsyslog.d/*", "/etc/rsyslog.d/"]
 COPY ["root/.vimrc", "/root/.vimrc"]
 
 RUN ln /usr/bin/vim.tiny /usr/bin/vim
 
 COPY ["etc/supervisor/supervisord.conf", "/etc/supervisor/"]
+COPY ["etc/supervisor/containercfgd.conf", "/etc/supervisor/conf.d/"]

dockers/docker-base-bullseye/etc/supervisor/containercfgd.conf

@@ -0,0 +1,9 @@
+[program:containercfgd]
+command=python3 /usr/local/bin/containercfgd
+priority=99
+autostart=false
+autorestart=unexpected
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running

dockers/docker-base-buster/Dockerfile.j2

@@ -94,7 +94,7 @@ RUN pip3 install supervisor==4.2.1
 # Add support for supervisord to handle startup dependencies
 RUN pip3 install supervisord-dependent-startup==1.4.0
 
-RUN mkdir -p /etc/supervisor /var/log/supervisor
+RUN mkdir -p /var/log/supervisor /etc/supervisor/conf.d
 
 RUN apt-get -y purge   \
     exim4              \
@@ -117,10 +117,10 @@ RUN apt-get clean -y                     && \
     apt-get autoremove -y                && \
     rm -rf /var/lib/apt/lists/* /tmp/* ~/.cache/
 
-COPY ["etc/rsyslog.conf", "/etc/rsyslog.conf"]
 COPY ["etc/rsyslog.d/*", "/etc/rsyslog.d/"]
 COPY ["root/.vimrc", "/root/.vimrc"]
 
 RUN ln /usr/bin/vim.tiny /usr/bin/vim
 
 COPY ["etc/supervisor/supervisord.conf", "/etc/supervisor/"]
+COPY ["etc/supervisor/containercfgd.conf", "/etc/supervisor/conf.d/"]

dockers/docker-base-buster/etc/supervisor/containercfgd.conf

@@ -0,0 +1,9 @@
+[program:containercfgd]
+command=python3 /usr/local/bin/containercfgd
+priority=99
+autostart=false
+autorestart=unexpected
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running

dockers/docker-base-stretch/Dockerfile.j2

@@ -90,7 +90,7 @@ RUN pip install supervisor>=3.4.0
 # Add support for supervisord to handle startup dependencies
 RUN pip install supervisord-dependent-startup==1.4.0
 
-RUN mkdir -p /etc/supervisor /var/log/supervisor
+RUN mkdir -p /var/log/supervisor /etc/supervisor/conf.d
 
 RUN apt-get -y purge   \
     exim4              \
@@ -113,10 +113,10 @@ RUN apt-get clean -y                     && \
     apt-get autoremove -y                && \
     rm -rf /var/lib/apt/lists/* /tmp/*
 
-COPY ["etc/rsyslog.conf", "/etc/rsyslog.conf"]
 COPY ["etc/rsyslog.d/*", "/etc/rsyslog.d/"]
 COPY ["root/.vimrc", "/root/.vimrc"]
 
 RUN ln /usr/bin/vim.tiny /usr/bin/vim
 
 COPY ["etc/supervisor/supervisord.conf", "/etc/supervisor/"]
+COPY ["etc/supervisor/containercfgd.conf", "/etc/supervisor/conf.d/"]

dockers/docker-base-stretch/etc/supervisor/containercfgd.conf

@@ -0,0 +1,9 @@
+[program:containercfgd]
+command=python /usr/local/bin/containercfgd
+priority=99
+autostart=false
+autorestart=unexpected
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running

dockers/docker-base/Dockerfile.j2

@@ -49,7 +49,6 @@ RUN apt-get -y install \
     rsyslog            \
     less
 
-COPY ["etc/rsyslog.conf", "/etc/rsyslog.conf"]
 COPY ["etc/rsyslog.d/*", "/etc/rsyslog.d/"]
 COPY ["root/.vimrc", "/root/.vimrc"]
 
@@ -64,10 +63,11 @@ RUN pip install wheel
 # Install supervisor
 RUN pip install supervisor>=3.4.0
 
-RUN mkdir -p /etc/supervisor
+RUN mkdir -p /etc/supervisor/conf.d
 RUN mkdir -p /var/log/supervisor
 
 COPY ["etc/supervisor/supervisord.conf", "/etc/supervisor/"]
+COPY ["etc/supervisor/containercfgd.conf", "/etc/supervisor/conf.d/"]
 
 RUN apt-get -y purge   \
     exim4              \

dockers/docker-base/etc/supervisor/containercfgd.conf

@@ -0,0 +1,9 @@
+[program:containercfgd]
+command=python /usr/local/bin/containercfgd
+priority=99
+autostart=false
+autorestart=unexpected
+stdout_logfile=syslog
+stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running

dockers/docker-database/supervisord.conf.j2

@@ -3,6 +3,15 @@ logfile_maxbytes=1MB
 logfile_backups=2
 nodaemon=true
 
+[eventlistener:dependent-startup]
+command=python3 -m supervisord_dependent_startup
+autostart=true
+autorestart=unexpected
+startretries=0
+exitcodes=0,3
+events=PROCESS_STATE
+buffer_size=1024
+
 [eventlistener:supervisor-proc-exit-listener]
 command=/usr/bin/supervisor-proc-exit-listener --container-name database
 events=PROCESS_STATE_EXITED,PROCESS_STATE_RUNNING
@@ -13,10 +22,11 @@ buffer_size=1024
 [program:rsyslogd]
 command=/usr/sbin/rsyslogd -n -iNONE
 priority=1
-autostart=true
+autostart=false
 autorestart=false
 stdout_logfile=syslog
 stderr_logfile=syslog
+dependent_startup=true
 
 {% if INSTANCES %}
 {%     for redis_inst, redis_items in INSTANCES.items() %}
@@ -28,17 +38,21 @@ stderr_logfile=syslog
 {%- endif -%}
 command=/bin/bash -c "{ [[ -s /var/lib/{{ redis_inst }}/dump.rdb ]] || rm -f /var/lib/{{ redis_inst }}/dump.rdb; } && mkdir -p /var/lib/{{ redis_inst }} && exec /usr/bin/redis-server /etc/redis/redis.conf --bind {{ LOOPBACK_IP }} {{ redis_items['hostname'] }} --port {{ redis_items['port'] }} --unixsocket {{ redis_items['unix_socket_path'] }} --pidfile /var/run/redis/{{ redis_inst }}.pid --dir /var/lib/{{ redis_inst }}"
 priority=2
-autostart=true
+autostart=false
 autorestart=false
 stdout_logfile=syslog
 stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running
 {%     endfor %}
 {% endif %}
 
 [program:flushdb]
 command=/bin/bash -c "sleep 300 && /usr/local/bin/flush_unused_database"
 priority=3
-autostart=true
+autostart=false
 autorestart=false
 stdout_logfile=syslog
 stderr_logfile=syslog
+dependent_startup=true
+dependent_startup_wait_for=rsyslogd:running

files/build_templates/docker_image_ctl.j2

@@ -34,16 +34,23 @@ function updateSyslogConf()
     # Also update the container name
     if [[ ($NUM_ASIC -gt 1) ]]; then
         TARGET_IP=$(docker network inspect bridge --format={{ "'{{(index .IPAM.Config 0).Gateway}}'" }})
+    else
+        if [ "$CONTAINER_EXISTS" = "yes" ]; then
+            # database configuration has been synced to /etc/rsyslog.conf
+            # no need generate it to save boot time
+            return
+        fi
+        TARGET_IP="127.0.0.1"
+    fi
     CONTAINER_NAME="$DOCKERNAME"
     TMP_FILE="/tmp/rsyslog.$CONTAINER_NAME.conf"
     {%- if docker_container_name == "database" %}
     python -c "import jinja2, os; paths=['/usr/share/sonic/templates']; loader = jinja2.FileSystemLoader(paths); env = jinja2.Environment(loader=loader, trim_blocks=True); template_file='/usr/share/sonic/templates/rsyslog-container.conf.j2'; template = env.get_template(os.path.basename(template_file)); data=template.render({\"target_ip\":\"$TARGET_IP\",\"container_name\":\"$CONTAINER_NAME\"}); print(data)" > $TMP_FILE
     {%- else %}
-        sonic-cfggen -t /usr/share/sonic/templates/rsyslog-container.conf.j2 -a "{\"target_ip\": \"$TARGET_IP\", \"container_name\": \"$CONTAINER_NAME\" }"  > $TMP_FILE
+    sonic-cfggen -d -t /usr/share/sonic/templates/rsyslog-container.conf.j2 -a "{\"target_ip\": \"$TARGET_IP\", \"container_name\": \"$CONTAINER_NAME\" }"  > $TMP_FILE
     {%- endif %}
     docker cp $TMP_FILE ${DOCKERNAME}:/etc/rsyslog.conf
     rm -rf $TMP_FILE
-    fi
 }
 function ebtables_config()
 {
@@ -342,6 +349,7 @@ start() {
         DOCKERMOUNT=`getMountPoint "$DOCKERCHECK"`
         {%- endif %}
         if [ x"$DOCKERMOUNT" == x"$MOUNTPATH" ]; then
+            CONTAINER_EXISTS="yes"
             preStartAction
             {%- if docker_container_name == "database" %}
             echo "Starting existing ${DOCKERNAME} container"
@@ -536,6 +544,7 @@ start() {
 {%- endif %}
         $REDIS_MNT \
         -v /usr/share/sonic/device/$PLATFORM:/usr/share/sonic/platform:ro \
+        -v /usr/share/sonic/templates/rsyslog-container.conf.j2:/usr/share/sonic/templates/rsyslog-container.conf.j2:ro \
 {%- if sonic_asic_platform != "mellanox" %}
 {%- if mount_default_tmpfs|default("n") == "y" %}
         --tmpfs /tmp \
@@ -547,6 +556,7 @@ start() {
         --env "NAMESPACE_ID"="$DEV" \
         --env "NAMESPACE_PREFIX"="$NAMESPACE_PREFIX" \
         --env "NAMESPACE_COUNT"=$NUM_ASIC \
+        --env "CONTAINER_NAME"=$DOCKERNAME \
         --name=$DOCKERNAME \
 {%- if docker_container_name == "gbsyncd" %}
         -v /var/run/docker-syncd$DEV:/var/run/sswsyncd \
@@ -617,6 +627,7 @@ fi
 {%- endif %}
 NAMESPACE_PREFIX="asic"
 DOCKERNAME=$DOCKERNAME$DEV
+CONTAINER_EXISTS="no"
 if [ "$DEV" ]; then
     NET_NS="$NAMESPACE_PREFIX$DEV" #name of the network namespace
 

files/image_config/rsyslog/rsyslog-container.conf.j2

@@ -14,8 +14,24 @@ $ModLoad imuxsock # provides support for local system logging
 #
 # Set a rate limit on messages from the container
 #
-$SystemLogRateLimitInterval 300
+
-$SystemLogRateLimitBurst 20000
+{% if SYSLOG_CONFIG_FEATURE is defined %}
+{% if container_name in SYSLOG_CONFIG_FEATURE %}
+{% if 'rate_limit_interval' in SYSLOG_CONFIG_FEATURE[container_name]%}
+{% set rate_limit_interval = SYSLOG_CONFIG_FEATURE[container_name]['rate_limit_interval'] %}
+{% endif %}
+{% if 'rate_limit_burst' in SYSLOG_CONFIG_FEATURE[container_name]%}
+{% set rate_limit_burst = SYSLOG_CONFIG_FEATURE[container_name]['rate_limit_burst'] %}
+{% endif %}
+{% endif %}
+{% endif %}
+
+{% if rate_limit_interval is defined %}
+$SystemLogRateLimitInterval {{ rate_limit_interval }}
+{% endif %}
+{% if rate_limit_burst is defined %}
+$SystemLogRateLimitBurst {{ rate_limit_burst }}
+{% endif %}
 
 #$ModLoad imklog  # provides kernel logging support
 #$ModLoad immark  # provides --MARK-- message capability

rules/docker-config-engine-bullseye.mk

@@ -12,7 +12,8 @@ $(DOCKER_CONFIG_ENGINE_BULLSEYE)_DEPENDS += $(LIBSWSSCOMMON) \
                                           $(SONIC_EVENTD)
 $(DOCKER_CONFIG_ENGINE_BULLSEYE)_PYTHON_WHEELS += $(SONIC_PY_COMMON_PY3) \
                                                   $(SONIC_YANG_MGMT_PY3) \
-                                                $(SONIC_YANG_MODELS_PY3)
+                                                  $(SONIC_YANG_MODELS_PY3) \
+                                                  $(SONIC_CONTAINERCFGD)
 $(DOCKER_CONFIG_ENGINE_BULLSEYE)_PYTHON_WHEELS += $(SONIC_CONFIG_ENGINE_PY3)
 $(DOCKER_CONFIG_ENGINE_BULLSEYE)_LOAD_DOCKERS += $(DOCKER_BASE_BULLSEYE)
 $(DOCKER_CONFIG_ENGINE_BULLSEYE)_FILES += $(SWSS_VARS_TEMPLATE)

rules/docker-config-engine-buster.mk

@@ -11,7 +11,8 @@ $(DOCKER_CONFIG_ENGINE_BUSTER)_DEPENDS += $(LIBSWSSCOMMON) \
                                           $(SONIC_DB_CLI)
 $(DOCKER_CONFIG_ENGINE_BUSTER)_PYTHON_WHEELS += $(SONIC_PY_COMMON_PY3) \
                                                 $(SONIC_YANG_MGMT_PY3) \
-                                                $(SONIC_YANG_MODELS_PY3)
+                                                $(SONIC_YANG_MODELS_PY3) \
+                                                $(SONIC_CONTAINERCFGD)
 $(DOCKER_CONFIG_ENGINE_BUSTER)_PYTHON_WHEELS += $(SONIC_CONFIG_ENGINE_PY3)
 $(DOCKER_CONFIG_ENGINE_BUSTER)_LOAD_DOCKERS += $(DOCKER_BASE_BUSTER)
 $(DOCKER_CONFIG_ENGINE_BUSTER)_FILES += $(SWSS_VARS_TEMPLATE)

rules/sonic-containercfgd.dep

@@ -0,0 +1,10 @@
+SPATH       := $($(SONIC_CONTAINERCFGD)_SRC_PATH)
+DEP_FILES   := $(SONIC_COMMON_FILES_LIST) rules/sonic-containercfgd.mk rules/sonic-containercfgd.dep
+DEP_FILES   += $(SONIC_COMMON_BASE_FILES_LIST)
+SMDEP_FILES := $(addprefix $(SPATH)/,$(shell cd $(SPATH) && git ls-files))
+
+$(SONIC_CONTAINERCFGD)_CACHE_MODE  := GIT_CONTENT_SHA
+$(SONIC_CONTAINERCFGD)_DEP_FLAGS   := $(SONIC_COMMON_FLAGS_LIST)
+$(SONIC_CONTAINERCFGD)_DEP_FILES   := $(DEP_FILES)
+$(SONIC_CONTAINERCFGD)_SMDEP_FILES := $(SMDEP_FILES)
+$(SONIC_CONTAINERCFGD)_SMDEP_PATHS := $(SPATH)

rules/sonic-containercfgd.mk

@@ -0,0 +1,8 @@
+# sonic-bgpcfgd package
+
+SONIC_CONTAINERCFGD = sonic_containercfgd-1.0-py3-none-any.whl
+$(SONIC_CONTAINERCFGD)_SRC_PATH = $(SRC_PATH)/sonic-containercfgd
+$(SONIC_CONTAINERCFGD)_DEPENDS += $(SONIC_PY_COMMON_PY3)
+$(SONIC_CONTAINERCFGD)_DEBS_DEPENDS = $(LIBSWSSCOMMON) $(PYTHON3_SWSSCOMMON)
+$(SONIC_CONTAINERCFGD)_PYTHON_VERSION = 3
+SONIC_PYTHON_WHEELS += $(SONIC_CONTAINERCFGD)

src/sonic-containercfgd/.gitignore

@@ -0,0 +1,13 @@
+# Compiled Python files
+*.pyc
+
+# Generated by packaging
+*.egg-info/
+.eggs/
+build/
+dist/
+
+# Unit test coverage
+.coverage
+coverage.xml
+htmlcov/

src/sonic-containercfgd/containercfgd/containercfgd.py

@@ -0,0 +1,198 @@
+import os
+import re
+import signal
+import subprocess
+import sys
+
+from sonic_py_common import daemon_base, logger
+from swsscommon.swsscommon import ConfigDBConnector, RestartWaiter
+
+SYSLOG_IDENTIFIER = "containercfgd"
+logger = logger.Logger(SYSLOG_IDENTIFIER)
+
+# Table names
+FEATURE_TABLE = 'FEATURE'
+SYSLOG_CONFIG_FEATURE_TABLE = 'SYSLOG_CONFIG_FEATURE'
+
+# Table field names
+SYSLOG_RATE_LIMIT_INTERVAL = 'rate_limit_interval'
+SYSLOG_RATE_LIMIT_BURST = 'rate_limit_burst'
+
+# Container name
+container_name = None
+
+
+def run_command(command):
+    """
+    Utility function to run an shell command and return the output.
+    :param command: Shell command string.
+    :return: Output of the shell command.
+    """
+    return subprocess.check_output(command, text=True, stderr=subprocess.PIPE)
+
+
+class ContainerConfigDaemon(daemon_base.DaemonBase):
+    handlers = {}
+
+    def __init__(self):
+        super(ContainerConfigDaemon, self).__init__(SYSLOG_IDENTIFIER)
+
+    def run(self):
+        """Register config handlers and listen to CONFIG DB changes
+        """
+        config_db = ConfigDBConnector()
+        config_db.connect(wait_for_init=True, retry_on=True)
+        self.log_notice(f'Connected to CONFIG DB')
+        for table_name, handler in self.handlers.items():
+            config_db.subscribe(table_name, handler.handle_config)
+        config_db.listen(init_data_handler=self.init_data_handler)
+
+    def init_data_handler(self, init_data):
+        """Handle initial data in CONFIG DB
+
+        Args:
+            init_data (dict): Initial data when first time connecting to CONFIG DB. {<table_name>: {<field_name>: <field_value>}}
+        """
+        for handler in self.handlers.values():
+            handler.handle_init_data(init_data)
+
+    @classmethod
+    def register_handler(cls, table_name, object_type):
+        """Register CONFIG DB handler
+
+        Args:
+            table_name (str): CONFIG DB table name
+            object_type (class): Class of CONFIG DB handler
+        """
+        cls.handlers[table_name] = object_type()
+
+    def signal_handler(self, sig, frame):
+        if sig == signal.SIGHUP:
+            self.log_info("ContainerCfgd: Caught SIGHUP - ignoring...")
+        elif sig == signal.SIGINT:
+            self.log_info("ContainerCfgd: Caught SIGINT - exiting...")
+            sys.exit(128 + sig)
+        elif sig == signal.SIGTERM:
+            self.log_info("ContainerCfgd: Caught SIGTERM - exiting...")
+            sys.exit(128 + sig)
+        else:
+            self.log_warning("ContainerCfgd: Caught unhandled signal '{}'".format(sig))
+
+
+def config_handler(table_name):
+    """Decorator to register CONFIG DB handler
+
+    Args:
+        table_name (str): CONFIG DB table name
+    """
+    def wrapper(object_type):
+        ContainerConfigDaemon.register_handler(table_name, object_type)
+        return object_type
+    return wrapper
+
+
+@config_handler(SYSLOG_CONFIG_FEATURE_TABLE)
+class SyslogHandler:
+    # syslog conf file path in docker
+    SYSLOG_CONF_PATH = '/etc/rsyslog.conf'
+    # temporary syslog conf file path in docker
+    TMP_SYSLOG_CONF_PATH = '/tmp/rsyslog.conf'
+
+    # Regular expressions to extract value from rsyslog.conf
+    INTERVAL_PATTERN = '.*SystemLogRateLimitInterval\s+(\d+).*'
+    BURST_PATTERN = '.*SystemLogRateLimitBurst\s+(\d+).*'
+    TARGET_IP_PATTERN = '.*target="(.*?)".*'
+
+    def __init__(self):
+        self.current_interval, self.current_burst, self.target_ip = self.parse_syslog_conf()
+
+    def handle_config(self, table, key, data):
+        """Handle CONFIG DB change. Callback by ConfigDBConnector.
+
+        Args:
+            table (str): CONFIG DB table name
+            key (str): Key of the changed entry
+            data (dict): Data of the entry: {<field_name>: <field_value>}
+        """
+        try:
+            if key != container_name:
+                return
+            self.update_syslog_config(data)
+        except Exception as e:
+            logger.log_error('Failed to config syslog for container {} with data {} - {}'.format(key, data, e))
+
+    def handle_init_data(self, init_data):
+        """Handle initial data in CONFIG DB. Callback by ConfigDBConnector.
+
+        Args:
+            init_data (dict): Initial data when first time connecting to CONFIG DB. {<table_name>: {<field_name>: <field_value>}}
+        """
+        if SYSLOG_CONFIG_FEATURE_TABLE in init_data:
+            if container_name in init_data[SYSLOG_CONFIG_FEATURE_TABLE]:
+                self.update_syslog_config(init_data[SYSLOG_CONFIG_FEATURE_TABLE][container_name])
+
+    def update_syslog_config(self, data):
+        """Parse existing syslog conf and apply new syslog conf.
+
+        Args:
+            data (dict): Data of the entry: {<field_name>: <field_value>}
+        """
+        new_interval = '0' if not data else data.get(SYSLOG_RATE_LIMIT_INTERVAL, '0')
+        new_burst = '0' if not data else data.get(SYSLOG_RATE_LIMIT_BURST, '0')
+
+        if new_interval == self.current_interval and new_burst == self.current_burst:
+            logger.log_notice('Syslog rate limit configuration does not change, ignore it')
+            return
+
+        logger.log_notice(f'Configure syslog rate limit interval={new_interval}, burst={new_burst}')
+
+        if os.path.exists(self.TMP_SYSLOG_CONF_PATH):
+            os.remove(self.TMP_SYSLOG_CONF_PATH)
+        with open(self.TMP_SYSLOG_CONF_PATH, 'w+') as f:
+            json_args = f'{{"target_ip": "127.0.0.1", "{self.target_ip}": "{container_name}" }}'
+            output = run_command(['sonic-cfggen', '-d', '-t', '/usr/share/sonic/templates/rsyslog-container.conf.j2', '-a', json_args])
+            f.write(output)
+        run_command(['cp', self.TMP_SYSLOG_CONF_PATH, self.SYSLOG_CONF_PATH])
+        run_command(['supervisorctl', 'restart', 'rsyslogd'])
+        self.current_interval = new_interval
+        self.current_burst = new_burst
+
+    def parse_syslog_conf(self):
+        """Passe existing syslog conf and extract config values
+
+        Returns:
+            tuple: interval,burst,target_ip
+        """
+        interval = '0'
+        burst = '0'
+        target_ip = None
+
+        with open(self.SYSLOG_CONF_PATH, 'r') as f:
+            content = f.read()
+            pattern = re.compile(self.INTERVAL_PATTERN)
+            for match in pattern.finditer(content):
+                interval = match.group(1)
+                break
+
+            pattern = re.compile(self.BURST_PATTERN)
+            for match in pattern.finditer(content):
+                burst = match.group(1)
+                break
+
+            pattern = re.compile(self.TARGET_IP_PATTERN)
+            for match in pattern.finditer(content):
+                target_ip = match.group(1)
+                break
+        return interval, burst, target_ip
+
+
+def main():
+    RestartWaiter.waitAdvancedBootDone()
+    global container_name
+    container_name = os.environ['CONTAINER_NAME']
+    daemon = ContainerConfigDaemon()
+    daemon.run()
+
+
+if __name__ == '__main__':
+    main()

src/sonic-containercfgd/pytest.ini

@@ -0,0 +1,2 @@
+[pytest]
+addopts = --cov=containercfgd --cov-report html --cov-report term --cov-report xml

src/sonic-containercfgd/setup.cfg

@@ -0,0 +1,2 @@
+[aliases]
+test=pytest

src/sonic-containercfgd/setup.py

@@ -0,0 +1,48 @@
+from setuptools import setup
+
+dependencies = [
+    'sonic_py_common',
+]
+
+setup(
+    name='sonic-containercfgd',
+    version='1.0',
+    description='SONiC container config daemon package',
+    license='Apache 2.0',
+    author='SONiC Team',
+    author_email='linuxnetdev@microsoft.com',
+    url='https://github.com/Azure/sonic-buildimage',
+    maintainer='Junchao Chen',
+    maintainer_email='junchaow@nvidia.com',
+    install_requires=dependencies,
+    entry_points={
+        'console_scripts': [
+            'containercfgd = containercfgd.containercfgd:main',
+        ]
+    },
+    packages=[
+        'containercfgd',
+        'tests'
+    ],
+    setup_requires=[
+        'pytest-runner'
+    ],
+    tests_require=[
+        'pytest',
+        'mock>=2.0.0'
+    ],
+    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 :: 3.7',
+        'Topic :: System :: Hardware',
+    ],
+    keywords='SONiC sonic container config daemon',
+    test_suite='setup.get_test_suite'
+)

src/sonic-containercfgd/tests/conftest.py

@@ -0,0 +1,7 @@
+import os
+
+
+def init_env():
+    # Just make sure there is an environment variable CONTAINER_NAME
+    # The value of this environment variable is not important
+    os.environ["CONTAINER_NAME"] = "some_container"

src/sonic-containercfgd/tests/mock_rsyslog.conf

@@ -0,0 +1,29 @@
+$ModLoad imuxsock # provides support for local system logging
+
+#
+# Set a rate limit on messages from the container
+#
+
+
+$SystemLogRateLimitInterval 50
+$SystemLogRateLimitBurst 10002
+
+#$ModLoad imklog  # provides kernel logging support
+#$ModLoad immark  # provides --MARK-- message capability
+
+# provides UDP syslog reception
+#$ModLoad imudp
+#$UDPServerRun 514
+
+# provides TCP syslog reception
+#$ModLoad imtcp
+#$InputTCPServerRun 514
+
+
+###########################
+#### GLOBAL DIRECTIVES ####
+###########################
+
+# Set remote syslog server
+template (name="ForwardFormatInContainer" type="string" string="<%PRI%>%TIMESTAMP:::date-rfc3339% %HOSTNAME% pmon#%syslogtag%%msg:::sp-if-no-1st-sp%%msg%")
+*.* action(type="omfwd" target="127.0.0.1" port="514" protocol="udp" Template="ForwardFormatInContainer")

src/sonic-containercfgd/tests/test_config_daemon.py

@@ -0,0 +1,54 @@
+import os
+import sys
+from unittest import mock
+
+test_path = os.path.dirname(os.path.abspath(__file__))
+modules_path = os.path.dirname(test_path)
+sys.path.insert(0, modules_path)
+
+from containercfgd import containercfgd
+
+
+@containercfgd.config_handler('MockTable')
+class MockHandler:
+    def handle_init_data(self, init_data):
+        pass
+
+    def handle_config(self, table, key, data):
+        pass
+
+
+def test_handler_register():
+    assert 'MockTable' in containercfgd.ContainerConfigDaemon.handlers
+    assert isinstance(containercfgd.ContainerConfigDaemon.handlers['MockTable'], MockHandler)
+
+
+def test_init_data_handler():
+    mock_handler_cls = mock.MagicMock()
+    mock_handler_instance = mock.MagicMock()
+    mock_handler_instance.handle_init_data = mock.MagicMock()
+    mock_handler_cls.return_value = mock_handler_instance
+
+    containercfgd.ContainerConfigDaemon.register_handler('LoadMock', mock_handler_cls)
+    daemon = containercfgd.ContainerConfigDaemon()
+    daemon.init_data_handler({})
+    mock_handler_instance.handle_init_data.assert_called_once()
+    containercfgd.ContainerConfigDaemon.handlers.pop('LoadMock')
+
+
+@mock.patch('containercfgd.containercfgd.ConfigDBConnector')
+def test_run(mock_connector):
+    mock_db = mock.MagicMock()
+    mock_db.connect = mock.MagicMock()
+    mock_db.subscribe = mock.MagicMock()
+    mock_db.listen = mock.MagicMock()
+    mock_connector.return_value = mock_db
+
+    daemon = containercfgd.ContainerConfigDaemon()
+    daemon.run()
+    mock_db.connect.assert_called_once()
+    expected = []
+    for table_name, handler in containercfgd.ContainerConfigDaemon.handlers.items():
+        expected.append(mock.call(table_name, handler.handle_config))
+    mock_db.subscribe.assert_has_calls(expected, any_order=True)
+    mock_db.listen.assert_called_once()

src/sonic-containercfgd/tests/test_syslog_config.py

@@ -0,0 +1,81 @@
+import os
+import sys
+from unittest import mock
+
+test_path = os.path.dirname(os.path.abspath(__file__))
+modules_path = os.path.dirname(test_path)
+sys.path.insert(0, modules_path)
+
+from containercfgd import containercfgd
+
+containercfgd.container_name = 'swss'
+
+
+def test_handle_config():
+    handler = containercfgd.SyslogHandler()
+    handler.update_syslog_config = mock.MagicMock()
+
+    handler.handle_config(containercfgd.SYSLOG_CONFIG_FEATURE_TABLE,
+                          'bgp',
+                          None)
+    handler.update_syslog_config.assert_not_called()
+
+    handler.handle_config(containercfgd.SYSLOG_CONFIG_FEATURE_TABLE,
+                          'swss',
+                          None)
+    handler.update_syslog_config.assert_called_once()
+
+    handler.update_syslog_config.side_effect = Exception('')
+    handler.handle_config(containercfgd.SYSLOG_CONFIG_FEATURE_TABLE,
+                          'swss',
+                          None)
+
+
+def test_handle_init_data():
+    handler = containercfgd.SyslogHandler()
+    handler.update_syslog_config = mock.MagicMock()
+
+    init_data = {}
+    handler.handle_init_data(init_data)
+    handler.update_syslog_config.assert_not_called()
+
+    init_data = {containercfgd.SYSLOG_CONFIG_FEATURE_TABLE: {}}
+    handler.handle_init_data(init_data)
+    handler.update_syslog_config.assert_not_called()
+
+    init_data = {containercfgd.SYSLOG_CONFIG_FEATURE_TABLE: {'swss': {}}}
+    handler.handle_init_data(init_data)
+    handler.update_syslog_config.assert_called_once()
+
+
+@mock.patch('containercfgd.containercfgd.run_command')
+@mock.patch('containercfgd.containercfgd.SyslogHandler.parse_syslog_conf', mock.MagicMock(return_value=('100', '200', '127.0.0.1')))
+def test_update_syslog_config(mock_run_cmd):
+    mock_run_cmd.return_value = ""
+    handler = containercfgd.SyslogHandler()
+
+    data = {containercfgd.SYSLOG_RATE_LIMIT_INTERVAL: '100',
+            containercfgd.SYSLOG_RATE_LIMIT_BURST: '200'}
+    handler.update_syslog_config(data)
+    mock_run_cmd.assert_not_called()
+
+    data = {containercfgd.SYSLOG_RATE_LIMIT_INTERVAL: '200',
+            containercfgd.SYSLOG_RATE_LIMIT_BURST: '200'}
+
+    handler.update_syslog_config(data)
+    mock_run_cmd.assert_called()
+
+
+def test_parse_syslog_conf():
+    handler = containercfgd.SyslogHandler()
+    handler.SYSLOG_CONF_PATH = os.path.join(test_path, 'mock_rsyslog.conf')
+    interval, burst, target_ip = handler.parse_syslog_conf()
+    assert interval == '50'
+    assert burst == '10002'
+    assert target_ip == '127.0.0.1'
+
+    handler.SYSLOG_CONF_PATH = os.path.join(test_path, 'mock_empty_rsyslog.conf')
+    interval, burst, target_ip = handler.parse_syslog_conf()
+    assert interval == '0'
+    assert burst == '0'
+    assert target_ip is None