CLI command to load config in Yang format

[arlakshm]

Signed-off-by: Arvindsrinivasan Lakshmi Narasimhan arlakshm@microsoft.com

What I did

To support loading configuration data in yang schema, the config load command is enchanced with the below options

• -t --file-format to specify the file-format. The config file can be yang or config_db format
• -r to restart the services. Currently this option is supported for yang file format only.

How I did it

Add the above mentioned cli options.
Add Unit tests

How to verify it

Verify the command on VS.

admin@vlab-01:~$ sudo config load -y -c yang -r /etc/sonic/yang_cfg.json
Disabling container monitoring ...
Stopping SONiC target ...
Running command: /usr/local/bin/sonic-cfggen -H -Y /etc/sonic/yang_cfg.json -j /etc/sonic/init_cfg.json --write-to-db
Restarting SONiC target ...
Enabling container monitoring ...
Reloading Monit configuration ...
Reinitializing monit daemon
Please note setting loaded from minigraph will be lost after system reboot.To preserve setting, run `config save`.
admin@vlab-01:~$ sudo config load -y -c yang  /etc/sonic/yang_cfg.json
Running command: /usr/local/bin/sonic-cfggen -H -Y /etc/sonic/yang_cfg.json -j /etc/sonic/init_cfg.json --write-to-db
Please note setting loaded from minigraph will be lost after system reboot.To preserve setting, run `config save`.
admin@vlab-01:~$ sudo config load
Load config in config_db format from the default config file(s) ? [y/N]: y
Running command: /usr/local/bin/sonic-cfggen -j /etc/sonic/config_db.json --write-to-db
admin@vlab-01:~$ sudo config load -y
Running command: /usr/local/bin/sonic-cfggen -j /etc/sonic/config_db.json --write-to-db

Previous command output (if the output of a command-line utility has changed)

New command output (if the output of a command-line utility has changed)

[qiluo-msft]

'-r'

Why require restart in design? #Closed

[arlakshm]

The command can be used for loading initial and incremental configuration from config_yang file.
When loading initial configuration, the intention is to replicate the behavior of config load_minigraph. The -r is introduced for this purpose.

[qiluo-msft]

loading initial configuration -> then config reload fit your purpose better.

[arlakshm]

On a new SONiC device, there no configuration, the initial config can be loaded yang_config to populate the initial configuration on the device. config load_minigraph does the similar thing.
config reload load the save configuration on the device and may not work in this case.

[qiluo-msft]

Offline discussed.

1. for loading initial config, we use config reload --file_format config_yang. It already has an option to restart service.
2. for incremental config, we use config replace. ref: https://github.com/Azure/SONiC/blob/master/doc/config-generic-update-rollback/SONiC_Generic_Config_Update_and_Rollback_Design.md
3. the semantice of load for incremental updating purpose is not well defined. It is lack the flexibility, such as removing existing config, so we will not continue implement for file_format config_yang.

[arlakshm]

Fixed this in the latest commit.

[qiluo-msft]

As comments

[arlakshm]

if filename is not None:

if filename is not None
->
if not filename

Refers to: config/main.py:1063 in 75f8d18. [](commit_id = 75f8d18, deletion_comment = False)

The existing code is fine, the check if not filename doesnt work

admin@vlab-01:/usr/local/lib/python3.7/dist-packages/config$ python3
Python 3.7.3 (default, Jan 22 2021, 20:04:44)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> filename=None
>>> if not filename:
...   cfg_files  = filename.split(',')
...
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
AttributeError: 'NoneType' object has no attribute 'split'
>>>

[arlakshm]

/Azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[arlakshm]

the swss test test_PerfAddRemoveRoute is failing consistently. The test doesn't seem to be related to this change. These failures seen on other PRs as well.

Retrying again..

[arlakshm]

/Azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).