Support for small to large footprint introspection database and query

The query processing ability from the API will also help automations that rely on scripts that run from the command line. Administrators generally prefer invocation from the command-line whenever possible. Health check by querying the introspection datastore as reported above is not only authoritative but also richer since all the components contribute to the data.

The REST API is a front for other tools and packages like command line interface and SDK which enable programmability for packaged queries of introspection store.  An SDK does away with the requirement on the client to make the REST calls directly. This is a best practice favored by many cloud providers who know their cloud computing capability will be called from a variety of clients and devices. A variety of programming languages can be used to provide the SDK which widens the client base. The SDKs are provided as a mere convenience so this could be something that the developer community might initiate and maintain. Another benefit to using the SDK is that now the API versioning and service maintenance onus is somewhat reduced as more customers use their language friendly SDK while the internal wire call compatibility may change. SDKs also support platform independent and interoperable programming which helps test and automation.

Similarly command line interface CLI also improves the customer base. Tests and automations can make use of commands and scripts to drive the service. This is a very powerful technique for administrators as well as for day to day usage by end users. Command line usage has one additional benefit - it can be used for troubleshooting and diagnostics. While SDKs provide an additional layer and are hosted on the client side, command line interface may be available on the server side and provide fewer variables to go wrong. With detailed logging and request-response capture CLI and SDK help ease the calls made to the services SDK so that clients don’t have to make the REST calls directly. This is a best practice favored by many cloud providers who know their cloud computing capability will be called from a variety of clients and devices. 

Similarly command line interface CLI also improve the customer base. Tests and automations can make use of commands and scripts to drive the service. This is a very powerful technique for administrators as well as for day to day usage by end users. Command line usage has one additional benefit - it can be used for troubleshooting and diagnostics. While SDKs provide an additional layer and are hosted on the client side, command line interface may be available on the server side and provide fewer variables to go wrong. With detailed logging and request-response capture CLI and SDK help ease the calls made to the services

One of the restrictions that comes with packaged queries exported via REST APIs is their ability to scale since they consume significant resources on the backend and continue to run for a long time. These restrictions cannot be relaxed without some reduction on their resource usage. The API must provide a way for consumers to launch several queries with trackers and they should be completed reliably even if they are done one by one.  This is facilitated with the help of a reference to the query and a progress indicator. The reference is merely an opaque identifier that only the system issues and uses to look up the status. The indicator could be another api that takes the reference and returns the status. It is relatively easy for the system to separate read-only status information from read-write operations so the number of times the status indicator is called has no degradation on the rest of the system. There is a clean separation of the status information part of the system which is usually periodically collected or pushed from the rest of the system. The separation of read-write from read-only also helps with their treatment differently. For example, it is possible to replace the technology for the read-only separately from the technology for read-write. Even the technology for read-only can be swapped from one to another for improvements on this side.