Change History

**Table 1** Change history
Date	Description
2022-07-19	Optimized the description of the cycle parameter in "Querying API Metric Statistics".
2021-07-31	Described how to publish an API.
2021-07-20	Added the API for querying the instance list to the public resource API.
2021-01-06	Added the description of API permissions and actions.
2021-01-04	Released the FDI APIs and LINK APIs of the V2 version. Added the query parameter and optimized the description of some parameters in the APIs for querying the MQS instance list, querying the topic list, and resending messages.
2020-12-24	Released public resource APIs and message integration APIs.
2020-09-29	Released the service integration APIs of V2 and modified parameters of the device integration APIs.
2020-07-28	Optimized the description of the required parameter in the APIs for creating an API, modifying an API, querying details about an API, creating a backend API, modifying a backend API, querying details about a backend API, and testing a backend API.
2020-06-29	Optimized the description of the dataFormatTrans and ruleSrcLevel parameters in the API for creating a rule engine source.
2020-03-30	Modified the error code description.
2019-12-17	Optimized sections "API Overview", "Calling APIs", and "Appendix".
2019-08-15	This issue is the first official release.