Generic_upater: Apply JSON change

generic_config_updater/change_applier.py

@@ -0,0 +1,103 @@
+import copy
+import json
+import importlib
+import os
+import syslog
+import tempfile
+from collections import defaultdict
+from swsscommon.swsscommon import ConfigDBConnector
+from .gu_common import log_error, log_debug, log_info
+
+
+def get_config_db():
+    config_db = ConfigDBConnector()
+    config_db.connect()
+    return config_db
+
+
+def set_config(config_db, tbl, key, data):
+    config_db.set_entry(tbl, key, data)
+
+
+UPDATER_CONF_FILE = "/etc/sonic/generic_config_updater.conf"
+updater_data = None
+
+class ChangeApplier:
+    def __init__(self):
+        global updater_data, log_level
+
+        self.config_db = get_config_db()
+        if updater_data == None:
+            with open(UPDATER_CONF_FILE, "r") as s:
+                updater_data = json.load(s)
+
+
+    def _invoke_cmd(cmd, old_cfg, upd_cfg, keys):
+        method_name = cmd.split(".")[-1]
+        module_name = ".".join(cmd.split(".")[0:-1])
+
+        module = importlib.import_module(module_name, package=None)
+        method_to_call = getattr(module, method_name)
+
+        return method_to_call(old_cfg, upd_cfg, keys)
+
+
+    def _services_validate(old_cfg, upd_cfg, keys):
+        lst_svcs = set()
+        lst_cmds = set()
+        if not keys:
+            keys[""] = {}
+        for tbl in keys:
+            lst_svcs.update(updater_data.get(tbl, {}).get("services_to_validate", []))
+        for svc in lst_svcs:
+            lst_cmds.update(updater_data.get(svc, {}).get("validate_commands", []))
+
+        for cmd in lst_cmds:
+            ret = _invoke_cmd(cmd, old_cfg, upd_cfg, keys)
+            if ret:
+                return ret
+        return 0
+
+
+    def _upd_data(self, tbl, run_tbl, upd_tbl, upd_keys):
+        for key in set(run_tbl.keys()).union(set(upd_tbl.keys())):
+            run_data = run_tbl.get(key, None)
+            upd_data = upd_tbl.get(key, None)
+
+            if run_data != upd_data:
+                set_config(self.config_db, tbl, key, upd_data)
+                upd_keys[tbl][key] = {}
+
+
+    def apply(self, change):
+        run_data = self._get_running_config()
+        upd_data = change.apply(copy.deepcopy(run_data))
+        upd_keys = defaultdict(dict)
+
+        for tbl in set(run_data.keys()).union(set(upd_data.keys())):
+            self._upd_data(tbl, run_data.get(tbl, {}),
+                    upd_data.get(tbl, {}), upd_keys)
+
+        ret = _services_validate(run_data, upd_data, upd_keys)
+        if not ret:
+            run_data = self._get_running_config()
+            if upd_data != run_data:
+                report_mismatch(run_data, upd_data)
+                ret = -1
+        return ret
+
+
+    def _get_running_config(self):
+        (_, fname) = tempfile.mkstemp(suffix="_changeApplier")
+        os.system("sonic-cfggen -d --print-data > {}".format(fname))
+        run_data = {}
+        with open(fname, "r") as s:
+            run_data = json.load(s)
+        if os.path.isfile(fname):
+            os.remove(fname)
+        return run_data
+
+
+
+
+

generic_config_updater/generic_updater.py

@@ -2,8 +2,12 @@
 import os
 from enum import Enum
 from .gu_common import GenericConfigUpdaterError, ConfigWrapper, \
-                       DryRunConfigWrapper, PatchWrapper
+                       DryRunConfigWrapper, PatchWrapper, \
+                       set_log_level
+
 from .patch_sorter import PatchSorter
+from .change_applier import ChangeApplier
+
 
 CHECKPOINTS_DIR = "/etc/sonic/checkpoints"
 CHECKPOINT_EXT = ".cp.json"
@@ -17,15 +21,12 @@ def release_lock(self):
         # TODO: Implement ConfigLock
         pass
 
-class ChangeApplier:
-    def apply(self, change):
-        # TODO: Implement change applier
-        raise NotImplementedError("ChangeApplier.apply(change) is not implemented yet")
 
 class ConfigFormat(Enum):
     CONFIGDB = 1
     SONICYANG = 2
 
+
 class PatchApplier:
     def __init__(self,
                  patchsorter=None,
@@ -297,7 +298,7 @@ def init_verbose_logging(self, verbose):
         # Usually logs have levels such as: error, warning, info, debug.
         # By default all log levels should show up to the user, except debug.
         # By allowing verbose logging, debug msgs will also be shown to the user.
-        pass
+        set_log_level(syslog.LOG_ERR if not verbose else syslog.LOG_DEBUG)
 
     def get_config_wrapper(self, dry_run):
         if dry_run:

generic_config_updater/generic_updater_config.conf.json

@@ -0,0 +1,44 @@
+{
+    "tables": {
+        "": {
+            "services_to_validate": [ "system_health" ]
+        },
+        "PORT": {
+            "services_to_validate": [ "port_service" ]
+        }
+    },
+    "README": [
+        'Validate_commands provides, module & method name as ',
+        '    <module name>.<method name>',
+        'NOTE: module name could have "."',
+        ' ',
+        'The last element separated by  "." is considered as ',
+        'method name',
+        '',
+        'e.g. "show.acl.test_acl"',
+        '',
+        'Here we load "show.acl" and call "test_acl" method on it.',
+        '',
+        'called as:',
+        '    <module>.<method>>(<config before change>, ',
+        '        <config after change>, <affected keys>)',
+        '    config is in JSON format as in config_db.json',
+        '    affected_keys in same format, but w/o value',
+        '    { "ACL_TABLE": { "SNMP_ACL": {} ... }, ...}',
+        '    The affected keys has "added", "updated" & "deleted"',
+        '',
+        'Multiple validate commands may be provided.',',
+        '',
+        'Note: The commands may be called in any order',
+        ''
+    ],
+    "services": {
+        "system_health": { 
+            "validate_commands": [ ]
+        },
+        "port_service": {
+            "validate_commands": [ ]
+        }
+    }
+}
+

generic_config_updater/gu_common.py

@@ -13,6 +13,36 @@
 class GenericConfigUpdaterError(Exception):
     pass
 
+log_level = syslog.LOG_ERR
+
+def _log_msg(lvl, m):
+    if lvl <= log_level:
+        syslog.syslog(lvl, m)
+        if log_level == syslog.LOG_DEBUG:
+            print(m)
+
+def log_error(m):
+    _log_msg(syslog.LOG_ERR, m)
+
+
+def log_info(m):
+    _log_msg(syslog.LOG_INFO, m)
+
+
+def log_debug(m):
+    _log_msg(syslog.LOG_DEBUG, m)
+
+
+def run_cmd(cmd):
+    proc = subprocess.run(cmd, shell=True, capture_output=True)
+    if proc.returncode:
+        log_error("Failed to run: ret={} cmd: {}".format(
+            proc.returncode, proc.args))
+        log_error(f"Failed to run: stdout: {proc.stdout}")
+        log_error(f"Failed to run: stderr: {proc.stderr}")
+    return proc.returncode
+
+
 class JsonChange:
     """
     A class that describes a partial change to a JSON object.