When creating an initial tree trunk for oper data walk, if the xpath
represents a leaf, the leaf is created with an incorrect empty value.
If it doesn't actually exist in daemon's oper data, its value is not
overwritten later and an empty value is returned in the result.
For example, when requesting
`/frr-interface:lib/interface[name='eth0']/description`, the result is:
```
{
"frr-interface:lib": {
"interface": [
{
"name": "eth0",
"description": ""
}
]
}
}
```
instead of an empty JSON that it should be.
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
Add configure.ac tests for libyang functions, if not present supply the
functionality ourselves in yang.[ch]
Signed-off-by: Christian Hopps <chopps@labn.net>
Allow user to specify full YANG compatible XPath 1.0 predicates. This
allows for trimming results of generic queries using functions and other
non-key predicates from XPath 1.0
Signed-off-by: Christian Hopps <chopps@labn.net>
Heard back from libyang folks that this is not something they consider part of
the API and/or are going to guarantee. So we cannot count on it. Expect keys at
any location on the child sibling list.
Signed-off-by: Christian Hopps <chopps@labn.net>
