[DASH] Add Yang definitions for DASH

[prsunny]

Why I did it

Introduce Sonic Yang for DASH for the following tables:

• VNET
• ENI
• ACL
• ROUTES
• MAPPING

How I did it

How to verify it

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111
• 202205
• 202211

Description for the changelog

Ensure to add label/tag for the feature raised. example - PR#2174 under sonic-utilities repo. where, Generic Config and Update feature has been labelled as GCU.

Link to config_db schema for YANG module changes

A picture of a cute animal (not mandatory but encouraged)

[chrispsommers]

Hi, do you intend to eventually provide test files which can be used by a gNMI client to sent to the northbound gNMI interface (for example, any number of CLI-type gNMI clients, or a library)? The .json files appear to be formatted for Redis DB importing.

[ganglyu]

When GNMI run yang validation, GNMI needs to read current config from ApplDB and merge with incoming config.
DASH_ROUTE_TABLE and DASH_VNET_MAPPING_TABLE have large number of entries, so it will spend too much time to read these 2 tables.
My suggestion is to ignore existing DASH_ROUTE_TABLE and DASH_VNET_MAPPING_TABLE in ApplDB, therefore we should use different name pattern for DASH_ROUTE_TABLE and DASH_VNET_MAPPING_TABLE, and then GNMI can ignore these 2 tables and only read other tables. For example, DASHI_ROUTE_TABLE and DASHI_VNET_MAPPING_TABLE

[prsunny]

I don't think gnmi should be reading current config from APPDB for Mapping and Routing. Lets discuss to understand your concern.

[ganglyu]

Maybe I can use redis api like redis.keys("DASH_") to read all the other DASH tables except Mapping and Routing, and then Mapping and Routing table should use different name pattern.
Please let me know what you think.

[prsunny]

Hi, do you intend to eventually provide test files which can be used by a gNMI client to sent to the northbound gNMI interface (for example, any number of CLI-type gNMI clients, or a library)? The .json files appear to be formatted for Redis DB importing.

@chrispsommers, i'll work with @ganglyu to provide example gnmi configuration (may not be full-fledged test files) to DASH repo.

[ganglyu]

Still need to discuss DASH yang models.

[stephenxs]

Hi @prsunny
Looks like it causes the follow error

admin@r-boxer-sw01:~$ sudo sonic-package-manager list
libyang[1]: Value "vnet-direct" does not satisfy the constraint "direct|vnet|vnet_direct|vnet_encap|drop|appliance|privatelink|privatelinknsg|servicetunnel" (range, length, or pattern). (path: /sonic-dash:action_type)
libyang[1]: Previous warning generated by XPath subexpression[54] "action_type = 'vnet-direct'".
libyang[1]: Value "vnet-direct" does not satisfy the constraint "direct|vnet|vnet_direct|vnet_encap|drop|appliance|privatelink|privatelinknsg|servicetunnel" (range, length, or pattern). (path: /sonic-dash:action_type)
libyang[1]: Previous warning generated by XPath subexpression[54] "action_type = 'vnet-direct'".
Name                Repository                                        Description                   Version       Status
------------------  ------------------------------------------------  ----------------------------  ------------  ---------
database            docker-database                                   SONiC database package        1.0.0         Built-In
dhcp-relay          docker-dhcp-relay                                 N/A                           1.0.0         Installed