Return "limits" of API accepted

[ronaldtse]

e.g.

GET /limits

{ "message_size_max": "100000", "processing_time_max": "15000" }

message_size_max: in bytes
processing_time_max: in ms

Or/and via GraphQL.

Originally posted by @ronaldtse in #1 (comment)

[phuonghuynh]

@ronaldtse API Gateway don't support GET method by default (in proxy mode). I will investigate solution add GET method

Could we use "processing_time_max_milliseconds" for more descriptive?

{ "message_size_max": "100000", "processing_time_max": "15000" }

[ronaldtse]

Could we use "processing_time_max_milliseconds" for more descriptive?

Of course.