chassisd crash: wrong type of argument to FieldValuePairs

[anamehra]

Description

Chassisd id crashing on Linecards:

Sep  6 15:37:14.559156 sfd-vt2-lc0 INFO pmon#supervisord: chassisd pzctl-zone3/power_state: All rails powered on
Sep  6 15:37:14.559285 sfd-vt2-lc0 INFO pmon#supervisord: chassisd Traceback (most recent call last):  
Sep  6 15:37:14.559285 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   File "/usr/local/bin/chassisd", line 624, in <module>
Sep  6 15:37:14.559293 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     main()                          
Sep  6 15:37:14.559301 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   File "/usr/local/bin/chassisd", line 619, in main
Sep  6 15:37:14.559391 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     chassisd.run()                  
Sep  6 15:37:14.559391 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   File "/usr/local/bin/chassisd", line 597, in run
Sep  6 15:37:14.559519 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     self.module_updater.module_db_update()
Sep  6 15:37:14.559519 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   File "/usr/local/bin/chassisd", line 309, in module_db_update
Sep  6 15:37:14.559627 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     hostname_fvs = swsscommon.FieldValuePairs([(CHASSIS_MODULE_INFO_SLOT_FIELD, self.my_slot), 
Sep  6 15:37:14.559627 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   File "/usr/lib/python3/dist-packages/swsscommon/swsscommon.py", line 229, in __init__
Sep  6 15:37:14.559627 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     _swsscommon.FieldValuePairs_swiginit(self, _swsscommon.new_FieldValuePairs(*args))
Sep  6 15:37:14.559644 sfd-vt2-lc0 INFO pmon#supervisord: chassisd TypeError: Wrong number or type of arguments for overloaded function 'new_FieldValuePairs'.                                         
Sep  6 15:37:14.559644 sfd-vt2-lc0 INFO pmon#supervisord: chassisd   Possible C/C++ prototypes are:    
Sep  6 15:37:14.559667 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     std::vector< std::pair< std::string,std::string > >::vector()
Sep  6 15:37:14.559667 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     std::vector< std::pair< std::string,std::string > >::vector(std::vector< std::pair< std::string,std::string > > const &)
Sep  6 15:37:14.559675 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     std::vector< std::pair< std::string,std::string > >::vector(std::vector< std::pair< std::string,std::string > >::size_type)
Sep  6 15:37:14.559675 sfd-vt2-lc0 INFO pmon#supervisord: chassisd     std::vector< std::pair< std::string,std::string > >::vector(std::vector< std::pair< std::string,std::string > >::size_type,std::vector<
std::pair< std::string,std::string > >::value_type const &) 

The issue is in the new code introduced by sonic-net/sonic-platform-daemons#394

      hostname_fvs = swsscommon.FieldValuePairs([(CHASSIS_MODULE_INFO_SLOT_FIELD, **self.my_slot**), 

                                                    (CHASSIS_MODULE_INFO_HOSTNAME_FIELD, hostname),
                                                    (CHASSIS_MODULE_INFO_NUM_ASICS_FIELD, str(len(module_info_dict[CHASSIS_MODULE_INFO_ASICS])))])

The API expects arg as string, self.my_slot should be str(self.my_slot)

Steps to reproduce the issue:

1. Load image on LC with above PR
2. check syslogs for pmon logs

Describe the results you received:

chassisd crashed

Describe the results you expected:

chassisd should not crash

Output of show version:

202205 ref c4c2c00c1132429e84b29ae61694d2dc9efe848a

Output of show techsupport:

(paste your output here or download and attach the file here )

Additional information you deem important (e.g. issue happens only occasionally):

[anamehra]

Looks like the code assumes that the get_my_slot API would provide a string. Is that expected? I do not see the module enforcing that.

[anamehra]

@abdosi , for your viz

[anamehra]

Fixed by #396