spike: transfer limits per Namespace, Customer, and Account

[adamdecaf]

PayGate Version: v0.8.0

Describe the problem Since PayGate supports multiple Namespaces each needs to have dynamic Transfer limits. Also, Customers and Accounts within a Namespace need their own limits.

This can be determined by underwriting, business / risk decisions, or other factors. If PayGate supports dynamic configuration (and a file based config?) to view/modify these it should support the dynamic needs of businesses.

What did you expect to see? HTTP endpoints for modifying these limits on a Namespace, Customer, and Account basis. Also required is viewing their current usage.

[adamdecaf]

Initial thoughts, so feedback is appreciated.

I don't think we should support both file configured limits and HTTP configured limits. HTTP limits would be stored in the database.

File Config

If we setup a map[string]config.FixedLimits for each namespace then PayGate could use them as overrides from the instance-wide limits.

transfers:
  limits: 
    // "fixed" is a key here for instance-wide limits
    namespace:
      "<namespace>":
        softLimit: "<string>" 
        hardLimit: "<string>" 

HTTP Endpoints

transfers:
  limits:
    http:
      database: true # Uses the root-level database config, only enable endpoints if this is `true`. 

This would setup endpoints on the admin HTTP server:

Get Namespace Limits

• GET /namespaces/:namespace:/limits

{
  "softLimit": "<string>",
  "hardLimit": "<string>"
}

TODO: Should we offer the existing usage?

Update Namespace Limits

• PUT /namespaces/:namespace:/limits

{
  "softLimit": "<string>",
  "hardLimit": "<string>"
}

Remove Namesapce Limit Overrides

• DELETE /namespaces/:namespace:/limits Removes the existing limit override for the tenantID.