Ydk

Python
* Updated [`cisco-ios-xr`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xr_6_3_1.json) bundle to support Cisco IOS XR 6.3.1 release
* Updated [`cisco-ios-xe`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xe_16_6_1_post1.json) bundle to continue to support Cisco IOS XE 16.6.1 release and make it compatible with `ydk core` version `0.6.1`
* Also updated [`openconfig`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/openconfig_0_1_4.json) bundle version 0.1.4 with additional support for optical transport (channel monitor, optical amplifier, terminal device and transport line)
* Improved Service Providers
* Improved Netconf Service Provider to support timeout and retrieving device capabilities ([217](https://github.com/CiscoDevNet/ydk-gen/issues/217), [#492](https://github.com/CiscoDevNet/ydk-gen/issues/492), [#557](https://github.com/CiscoDevNet/ydk-gen/issues/557))
* Decoupled path API-specific details from Service Provider and created Netconf & Restconf Session to be used instead of Provider in path API ([494](https://github.com/CiscoDevNet/ydk-gen/issues/494), [#511](https://github.com/CiscoDevNet/ydk-gen/issues/511))
* Fixed segmentation fault with the `openconfig-platform` model ([527](https://github.com/CiscoDevNet/ydk-gen/issues/527))
* Improved Netconf Service's `kill_session` method ([528](https://github.com/CiscoDevNet/ydk-gen/issues/528))

Note on cisco-ios-xe bundle
* As specified above, the [`cisco-ios-xe`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xe_16_6_1_post1.json) bundle version was updated to `16.6.1.post1` without any of the models being changed. This is because the already released `16.6.1` bundle is not compatible with the `ydk core` version `0.6.1`. So, when upgrading your `core` version to be `0.6.1`, please also update the XE bundle to version `16.6.1.post1`.

Documentation
* Fixed documentation issues for installation ([529](https://github.com/CiscoDevNet/ydk-gen/issues/529), [#531](https://github.com/CiscoDevNet/ydk-gen/issues/531), [#542](https://github.com/CiscoDevNet/ydk-gen/issues/542), [#541](https://github.com/CiscoDevNet/ydk-gen/issues/541))
* Improved API documentation ([424](https://github.com/CiscoDevNet/ydk-gen/issues/424), [#94](https://github.com/CiscoDevNet/ydk-gen/issues/94))

ydk-gen
* Improved model API generation
* reduced size of generated python model API ([544](https://github.com/CiscoDevNet/ydk-gen/issues/544))
* fixed issues with class names not following the CapWords style and models containing enum leafrefs ([538](https://github.com/CiscoDevNet/ydk-gen/issues/538), [#550](https://github.com/CiscoDevNet/ydk-gen/issues/550), [#475](https://github.com/CiscoDevNet/ydk-gen/issues/475))

Python
* Introduced new YDK python [`core`](https://github.com/CiscoDevNet/ydk-py/tree/master/core) package using [pybind11](https://github.com/pybind/pybind11) to wrap around YDK C++ [`core`](https://github.com/CiscoDevNet/ydk-cpp/tree/master/core) ([#507](https://github.com/CiscoDevNet/ydk-gen/pull/507))
* Introduced `ydk.path` module consisting of APIs to read, manipulate and write YANG data using XPath-like expressions
* Updated YDK services and providers to internally use the path API
* Introduced `RestconfServiceProvider` and `OpenDaylightServiceProvider`
* Updated `NetconfServiceProvider` to be able to download the device yang models on connecting to a device
* Introduced ability to encode/decode subtree XML in `CodecService` and changed `CRUDService` to use XML subtree filtering to create filters for the `read` operation
* Added equality/inequality operators to compare YDK model API objects
* Add option for TCP transport in `NetconfServiceProvider` ([476](https://github.com/CiscoDevNet/ydk-gen/pull/476), [#444](https://github.com/CiscoDevNet/ydk-gen/pull/444))
* Support `get`/`get-config` with no filter in path API ([503](https://github.com/CiscoDevNet/ydk-gen/pull/503))
* Introduce optimized on-demand yang model downloading for `NetconfServiceProvider` ([499](https://github.com/CiscoDevNet/ydk-gen/pull/499))
* Add support for choosing either a per-device or a common cache for storing downloaded yang models ([502](https://github.com/CiscoDevNet/ydk-gen/pull/502))
* Introduced encoding/decoding subtree XML in `CodecService` and changed `CRUDService` to use XML subtree filtering to create filters for the `read` operation ([489](https://github.com/CiscoDevNet/ydk-gen/pull/489))
* Added support for non-standard RPCs as well in path API ([498](https://github.com/CiscoDevNet/ydk-gen/pull/498))

ydk-gen
* Updated [`cisco-ios-xr`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xr_6_2_2.json) to support Cisco IOS XR 6.2.2 release
* Updated [`cisco-ios-xe`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xe_16_6_1.json) to support Cisco IOS XE 16.6.1 release
* Also updated [`openconfig`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/openconfig_0_1_3.json) and [`ietf`](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/ietf_0_1_3.json) bundles

Note on backward compatibility
The [backward incompatible](http://ydk.cisco.com/py/docs/backward_compatibility.html) changes introduced with `0.6.0` release include:

* **Installation:** When installing `YDK-Py`, there is a new system requirement which needs to be installed. This is the `libydk` library, which is available on the DevHub website for various OS platforms. Please refer to the [system requirements](https://github.com/CiscoDevNet/ydk-py/blob/master/README.rst#system-requirements) for details.
* **Windows support:** From release ``0.6.0`` onwards, YDK is no longer supported on the Windows platform. We plan to add back support for this platform in the future.
* **API changes:** Please refer to the [developer guide](http://ydk.cisco.com/py/docs/developer_guide.html) and [API guide](http://ydk.cisco.com/py/docs/api_guide.html) for details about APIs and how to use them.
* `NetconfServiceProvider` no longer has the `close()` method. There is no need to explicitly close the provider as it will be automatically cleaned up when the object goes out of scope.
* `YFilter` has replaced the functionality of the `READ` and `DELETE` objects
* When using logging, the suggested level for users of YDK is `INFO` as `DEBUG` provides highly detailed logging suitable for dvelopers working on YDK
* The type names of `enumerations` and `identities` no longer have `Enum` or `Identity` in their names. For example, the identity `InterfaceTypeIdentity` in `ydk.models.ietf.ietf_interfaces` is now renamed to just `InterfaceType`.
* The `is_config()` method is no longer available for the YDK model APIs. This may be added back in a future release.

* Fixed bundle `setup.py` to match ydk `core` dependency in bundle profile ([433](https://github.com/CiscoDevNet/ydk-gen/issues/443))
* Updated `lxml` dependency for ydk `core` package ([427](https://github.com/CiscoDevNet/ydk-gen/issues/427))
* Improved reading of data using `ExecutorService` ([332](https://github.com/CiscoDevNet/ydk-gen/issues/332)) and `CRUDService` ([#457](https://github.com/CiscoDevNet/ydk-gen/issues/457))
* Fixed encoding key elements of yang `list`s ([363](https://github.com/CiscoDevNet/ydk-gen/issues/363)) and operational data ([#452](https://github.com/CiscoDevNet/ydk-gen/issues/452), [#455](https://github.com/CiscoDevNet/ydk-gen/issues/455))
* Added [`cisco-ios-xe` bundle](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xe_16_5_1.json) to support Cisco IOS XE 16.5.1 release

Documentation
* Improved getting-started guides for YDK-Py and YDK-Cpp ([418](https://github.com/CiscoDevNet/ydk-gen/pull/418), [#419](https://github.com/CiscoDevNet/ydk-gen/pull/419))
* Made table of contents for bundle documentation be sorted alphabetically ([446](https://github.com/CiscoDevNet/ydk-gen/pull/418), [#419](https://github.com/CiscoDevNet/ydk-gen/pull/446))
* Improved documentation of `rpc` classes ([435](https://github.com/CiscoDevNet/ydk-gen/issues/435))

* Improved logging to indicate message directionality ([388](https://github.com/CiscoDevNet/ydk-gen/pull/388))
* Provide more details for validation error message for leaf-lists ([398](https://github.com/CiscoDevNet/ydk-gen/pull/398))
* Remove indirect python requirements from `setup.py` ([392](https://github.com/CiscoDevNet/ydk-gen/pull/392))
* If validation error occurs when decoding payload, include payload as an attribute of the `YPYModelError` raised ([381](https://github.com/CiscoDevNet/ydk-gen/pull/381))
* Updated [`cisco-ios-xr` bundle](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xr_6_2_1.json) to support Cisco IOS XR 6.2.1 release

Documentation
* Separated top data classes from type classes in table of contents ([372](https://github.com/CiscoDevNet/ydk-gen/pull/372))
* Fixed ydk version not being correctly printed for C++ documentation ([374](https://github.com/CiscoDevNet/ydk-gen/pull/374))
* Indicate bundle version in C++ and python bundle documentation ([383](https://github.com/CiscoDevNet/ydk-gen/pull/383))

* Fixed issues with netconf service ([323](https://github.com/CiscoDevNet/ydk-gen/issues/323), [#305](https://github.com/CiscoDevNet/ydk-gen/issues/305))
* Disambiguated model API classes called 'None' ([318](https://github.com/CiscoDevNet/ydk-gen/issues/318))
* Removed 'Bits' from classes representing bits leafs ([318](https://github.com/CiscoDevNet/ydk-gen/issues/318), [#320](https://github.com/CiscoDevNet/ydk-gen/issues/320))

Documentation

* Included model revision in documentation ([272](https://github.com/CiscoDevNet/ydk-gen/issues/272))
* Improved documentation for string leafs ([346](https://github.com/CiscoDevNet/ydk-gen/issues/346)), decimal64 leafs ([#300](https://github.com/CiscoDevNet/ydk-gen/issues/300), [#294](https://github.com/CiscoDevNet/ydk-gen/issues/294))
* Improved look and feel of documentation ([361](https://github.com/CiscoDevNet/ydk-gen/pull/361), [#356](https://github.com/CiscoDevNet/ydk-gen/pull/356))

* CRUD service / Codec service / Netconf service improvements
* Improved error handling for mismatched model API types ([241](https://github.com/CiscoDevNet/ydk-gen/issues/241))
* Fixed issues with certain operations in netconf service ([247](https://github.com/CiscoDevNet/ydk-gen/issues/247), [#248](https://github.com/CiscoDevNet/ydk-gen/issues/248), [#252](https://github.com/CiscoDevNet/ydk-gen/issues/252), [#235](https://github.com/CiscoDevNet/ydk-gen/issues/235))
* Fixed issue with CRUD service identityref keys ([257](https://github.com/CiscoDevNet/ydk-gen/issues/257))

* Bundle improvements
* Made generate.py executable ([227](https://github.com/CiscoDevNet/ydk-gen/issues/227))
* Removed auto capitalization of enum literals ([230](https://github.com/CiscoDevNet/ydk-gen/issues/230))
* Updated [`cisco-ios-xr` bundle](https://github.com/CiscoDevNet/ydk-gen/blob/master/profiles/bundles/cisco-ios-xr_6_1_2.json) to support Cisco IOS XR 6.1.2 release ([#316](https://github.com/CiscoDevNet/ydk-gen/pull/316))

* Logging improvements
* Improved logging for services and providers ([251](https://github.com/CiscoDevNet/ydk-gen/issues/251), [#254](https://github.com/CiscoDevNet/ydk-gen/issues/254), [#280](https://github.com/CiscoDevNet/ydk-gen/issues/280), [#283](https://github.com/CiscoDevNet/ydk-gen/issues/283), [#284](https://github.com/CiscoDevNet/ydk-gen/issues/284))

* Documentation improvements
* Added YDK logos and reorganized to be more readable ([301](https://github.com/CiscoDevNet/ydk-gen/pull/301), [#296](https://github.com/CiscoDevNet/ydk-gen/pull/296), [#289](https://github.com/CiscoDevNet/ydk-gen/pull/289))
* Improved documentation of YANG attributes like data type (configuration or state), default value, units, status etc ([249](https://github.com/CiscoDevNet/ydk-gen/issues/249), [#290](https://github.com/CiscoDevNet/ydk-gen/issues/290))
* Improved netconf service documentation ([235](https://github.com/CiscoDevNet/ydk-gen/issues/235))