rules

Documentation

Overview

Package rules contains implementations of rules that apply to Google APIs.

Rules are sorted into subpackages by the AIP (https://aip.dev/) that mandates the rule. Every rule represented in code here must be represented in English in a corresponding AIP. Conversely, anything mandated in an AIP should have a rule here if it is feasible to enforce in code (sometimes it is infeasible, however).

A rule is technically anything with a `GetName()`, `GetURI()“, and `Lint(*desc.FileDescriptorProto) []lint.Problem` method, but most rule authors will want to use the rule structs provided in the lint package (`&lint.MessageRule`, `&lint.FieldRule`, and so on). These run against each applicable descriptor in the file (`MessageRule` against every message, for example). They also have an `OnlyIf` property that can be used to run against a subset of descriptors.

A simple rule therefore looks like this:

var myRule = &lint.MessageRule{
  Name: lint.NewRuleName(1234, "my-rule"),
  LintMessage: func(m *desc.MessageDescriptor) []lint.Problem {
    if isBad(m) {
      return []lint.Problem{{
        Message: "This message is bad.",
        Descriptor: m,
      }}
    }
    return nil
  },
}

Once a rule is written, it needs to be registered. This involves adding the rule to the `AddRules` method for the appropriate AIP package. If this is the first rule for a new AIP, then the `rules.go` init() function must also be updated to run the `AddRules` function for the new package.

Index

• func Add(r lint.RuleRegistry) error

Functions

func Add

func Add(r lint.RuleRegistry) error

Add all rules to the given registry.