* This is an alternative to manage a clixon daemon via sudtemd, containerd or other
* One important special case is starting the clixon-restconf daemon internally
* This is how it works:
* Register a process via `clixon_process_register(h, name, namespace, argv, argc)`
* Use process-control RPC defined in clixon-lib.yang to start/stop/restart or query status on that process
* Example code in the main example
* Only requests on the form: `<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><edit-config>...` will be accepted
* All replies will be on the form: `<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">...`
* Requests such as: `<rpc><edit-config>...` will not be accepted.
* You can revert this behaviour (to clixon pre-4.6 behaviour) by enabling `CLICON_NAMESPACE_NETCONF_DEFAULT`
* This API change is a consequence of: [copy-config's RPC cxobj parameter does not contain namespace #131](https://github.com/clicon/clixon/issues/131)
* Reduced memory for attribute and body objects, see `XML_NEW_DIFFERENTIATE` compile-time option.
* Optimized cbuf handling in parsing and xml2cbuf functions.
* Optimized xml scanner to read strings rather than single chars
* Optimized xml_merge for the case of disjunct trees.
* Added: stats RPC for clixon XML and memory statistics.
* Added: restart-plugin RPC for restarting individual plugins without restarting backend.
* xml-stats moved from clixon-config.yang as state data to an rpc `datastats` in clixon-lib.yang
* Experimental: restart_plugin
* Two new plugin callbacks added
* ca_daemon: Called just after a server has "daemonized", ie put in background.
* ca_trans_commit_done: Called when all plugin commits have been done.
* Note: If you have used "end" callback and usign transaction data, you should probably use this instead.
* C-code changes:
- Replaced stream uri:s w constants
- Replaced large debug print code with single clicon_log_xml
- Restconf put and post handling refactored using new parse API
w-level general upgrades and as a complement to module-specific upgrade.
* Called on startup after initial XML parsing, but before module-specific upgrades
* Enabled by definign the `.ca_datastore_upgrade`
* [General-purpose upgrade documentation](https://clixon-docs.readthedocs.io/en/latest/backend.html#ge
neral-purpose)
* JSON parse error messages change from ` on line x: syntax error,..` to `json_parse: line x: syntax err
or`
* Unknown-element error message is more descriptive, eg from `namespace is: urn:example:clixon` to: `Fai
led to find YANG spec of XML node: x with parent: xp in namespace urn:example:clixon`.
* C-API parse and validation API more capable
* `xml_spec_populate` family of functions extended with three-value return values
* -1: error, 0: parse OK, 1: parse and YANG binding OK.
* `xml_parse` and `json_parse` API changes
* Three value returns: -1: error, 0: parse OK, 1: parse and YANG binding OK.
* Extended `xml_parse_file2` and `xml_parse_string2` extended API functions with all options available.
* New concept called `yang_bind` that defines how XML symbols are bound to YANG after parsing
* Existing API same except `xml_parse_file` `endtag` argument moved to `xml_parse_file2`
* C-API: Added instrumentation: `xml_size` and `xml_stats_get`.
* Fixed: Enabling modstate (CLICON_XMLDB_MODSTATE), changing a revision on a yang, and restarting made the backend daemon exit at start (thanks Matt)
* Also: ensure to load `ietf-yang-library.yang ` if CLICON_XMLDB_MODSTATE is set
Major New features
* New and updated search functions using xpath, api-path and instance-id
* New search functions using api-path and instance_id:
* C search functions: `clixon_find_instance_id()` and `clixon_find_api_path()`
* Binary search optimization in lists for indexed leafs in all three formats.
* This improves search performance to O(logN) which is drastical improvements for large lists.
* You can also register explicit indexes for making binary search (not only list keys)
* For more info, see docs at [paths](https://clixon-docs.readthedocs.io/en/latest/paths.html) and
[search](https://clixon-docs.readthedocs.io/en/latest/xml.html#searching-in-xml)
API changes on existing features (you may need to change your code)
* On failed validation of leafrefs, error message changed from: `No such leaf` to `No leaf <name> matching path <path>`.
* CLI Error message (clicon_rpc_generate_error()) changed when backend returns netconf error to be more descriptive:
* Original: `Config error: Validate failed. Edit and try again or discard changes: Invalid argument`
* New (example): `Netconf error: application operation-failed Identityref validation failed, undefined not derived from acl-base . Validate failed. Edit and try again or discard changes"
Minor changes
* Test framework
* Added `-- -S <file>` command-line to main example to be able to return any state to main example.
* Added `test/cicd` test scripts for running on a set of other hosts
* C-code restructuring
* clixon_yang.c partitioned and moved code into clixon_yang_parse_lib.c and clixon_yang_module.c and move back some code from clixon_yang_type.c.
* partly to reduce size, but most important to limit code that accesses internal yang structures, only clixon_yang.c does this now.
* Restconf RFC 8040 increased feature compliance
* Cache-Control: no-cache added in HTTP responses (RFC Section 5.5)
* Restconf monitoring capabilities (RFC Section 9.1)
* Added support for Yang extensions
* New plugin callback: ca_extension
* Main backend example includes example code on how to implement a Yang extension in a plugin.
* JSON changes
* Non-pretty-print output removed all extra spaces.
* Example: `{"nacm-example:x": 42}` --> {"nacm-example:x":42}`
* Empty JSON container changed from `null` to `{}`.
* Empty list and leafs remain as `null`
* Removed unnecessary configure dependencies
* libnsl, libcrypt, libm, if_vlan,...
* pseudo-plugin added, to enable callbacks also for main programs. Useful for extensions
* Yang Unique statements with multiple schema identifiers did not work on some platforms due to memory error.
The reason is to be conservative with the API. However, less used functions, such as xpath_vec_bool(), xpath_vec_ctx() and xpath_vec_flag() are changed with a new `nsc`parameter, which should be set to NULL in most cases.
* Accepted:
```
curl -X PUT http://localhost/restconf/data/mod:a -d {"mod:a":"x"}
```
* Not accepted (must prefix "a" with module):
```
curl -X PUT http://localhost/restconf/data/mod:a -d {"a":"x"}
```
* Undefine `RESTCONF_NS_DATA_CHECK` in include/clixon_custom.h to disable strict check.
* Added check for libxml in configure';
* Added clixon_util_regexp utility function
* Yang state get improvements
* Integrated state and config into same tree on retrieval, not separate trees
* Added cli functions `cli_show_config_state()` and `cli_show_auto_state()` for showing combined config and state info.
* Added integrated state in the main example: `interface/oper-state`.
* Added performance tests for getting state, see [test/test_perf_state.sh].
* New xmldb_get1() returning actual cache - not a copy. This has lead to some householding instead of just deleting the copy
* xml_diff rewritten to work linearly instead of O(2)
* New xml_insert function using tree search. The new code uses this in insertion xmldb_put and defaults. (Note previous xml_insert renamed to xml_wrap_all)
