Sweetcomb/Sysrepo
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Contents
Sysrepo
In our case, there are two types of callbacks we can register
- callbacks for operational data/State callback : In sweetcomb, they are registered with method GETITEM and sysrepo register them with sr_dp_get_items_subscribe(). These are the callbacks triggered by a NETFCONF get RPC with Netopeer2.
- callbacks for configuration data : In sweetcomb, they are registered with method XPATH and sysrepo register them with sr_subtree_change_subscribe(). These are the callbacks triggered by a NETCONF edit-config RPC with Netopeer2.
Parsing XPATH
Writing a configuration callback
Events
A configuration callback is usually called twice for a single edit-config RPC. First, with SR_EV_VERIFY event and then with SR_EV_APPLY event.
- SR_EV_VERIFY : As it is the only phase which can return an error, in Sweetcomb, this is where VPP configuration happens.
- SR_EV_APPLY : Nothing is done for a SR_EV_APPLY in sweetcomb.
NB: errors are reported to the user with sr_set_error and SR_ERR_* return code.
Operations
- SR_OP_CREATED:
- SR_OP_MODIFIED:
- SR_OP_DELETED:
Writing a state callback
It is the job of the developper to build every XPATH which will be replied to the client. Every reply comes as a pair (xpath, value).
XPATH replied is built with : sr_val_build_xpath() The value which goes whith XPATH is built with sr_val_t array.
The argument sr_val_t **values and size_t *values_cnt of the callback must be filled respectively with value array and the number of replies.
