[IGNITE-8212] Binary Client Protocol spec: Key-Value Queries clarifications

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.4
• Fix Version/s: 2.7
• Component/s: documentation, thin client
• Assignee: Artem Budnikov
• Reporter: Alexey Kosenchuk
• Created: 10/Apr/18 22:22
• Updated: 14/Dec/18 13:21
• Resolved: 14/Dec/18 13:21

Description

https://apacheignite.readme.io/v2.6/docs/binary-client-protocol-key-value-operations

• all operations - "Flag. Pass 0 for default, or 1 to keep the value in binary form":
  • remove words about binary form and keep "Pass 0 for default" for all operations where this flag has no meaning.
  • clarify about binary form in operations where it has a meaning.

• OP_CACHE_GET: clarify that null is returned if the provided key does not exist in the cache.

• OP_CACHE_GET_AND_PUT: clarify that new entry is created, if the provided key does not exist in the cache, and null is returned in this case.

• OP_CACHE_GET_AND_REPLACE:
  • "if and only if there is a value currently mapped for that key" - is confusing. Is it possible that an existing key has no associated value? Suggest to rephrase as "if and only if the key exists in the cache"
  • clarify that null is returned if the key does not exist in the cache.

• OP_CACHE_GET_AND_REMOVE: clarify that null is returned if the key does not exist in the cache.

• OP_CACHE_PUT_IF_ABSENT: clarify what is "Success Flag" - true if the new entry is created, false if the specified key already exists in the cache.

• OP_CACHE_GET_AND_PUT_IF_ABSENT: "Previously contained value regardless of whether put happened or not" - is confusing. Suggest to rewrite "the current value associated with the key if it already exists in the cache, null if the new entry is created".

• OP_CACHE_GET_SIZE: clarify Peek modes

• OP_CACHE_CLEAR_XXX and OP_CACHE_REMOVE_XXX:
  • what is the difference between the corresponding operations? Only in notifying / not notifying listeners and cache writers? Or there are other differences not clarified by the spec?
  • (the operations could be combined in one set - with a flag required/not required notifications)
  • there is OP_CACHE_REMOVE_IF_EQUALS. But there is no OP_CACHE_CLEAR_IF_EQUALS. Is it intentional?
  • OP_CACHE_REMOVE_KEY and OP_CACHE_REMOVE_IF_EQUALS have "Value indicating whether remove happened" in the response. But OP_CACHE_CLEAR_KEY does not have such a flag in the response. Is it intentional?
  • OP_CACHE_CLEAR_KEYS, OP_CACHE_REMOVE_KEYS: clarify that even if some of the specified keys do not exist other entries are removed anyway.

Issue Links

• relates to: IGNITE-8039 Binary Client Protocol spec: data types/format clarifications