internal/changelog/linter.go

// Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
// or more contributor license agreements. Licensed under the Elastic License 2.0;
// you may not use this file except in compliance with the Elastic License 2.0.

package changelog

import (
	"fmt"

	"github.com/spf13/afero"
	"github.com/spf13/viper"
)

func NewLinter(fs afero.Fs) Linter {
	return newLinter(fs)
}

type Linter struct {
	fs              afero.Fs
	entryValidators entryValidators
	errors          []error
}

func newLinter(fs afero.Fs) Linter {
	return Linter{
		fs:              fs,
		entryValidators: defaultEntryValidators,
	}
}

type LinterErrors []error

func (l Linter) Lint(dest, version string) []error {
	c, err := FromFile(l.fs, fmt.Sprintf("./%s/%s.yaml", dest, version))
	if err != nil {
		return []error{fmt.Errorf("error loading changelog from file: %w", err)}
	}

	for _, entry := range c.Entries {
		for _, validator := range l.entryValidators {
			err := validator(entry)
			if err != nil {
				l.errors = append(l.errors, err)
			}
		}
	}

	return l.errors
}

type entryValidationFn func(Entry) error
type entryValidators map[string]entryValidationFn

var defaultEntryValidators = entryValidators{
	"pr_multipleids":  validator_PRMultipleIDs,
	"pr_noids":        validator_PRnoIDs,
	"issue_noids":     validator_IssueNoIDs,
	"component_valid": validator_componentValid(viper.GetStringSlice("components")),
}

func validator_PRMultipleIDs(entry Entry) error {
	if len(entry.LinkedPR) > 1 {
		return fmt.Errorf("changelog entry: %s has multiple PR ids", entry.File.Name)
	}

	return nil
}

func validator_PRnoIDs(entry Entry) error {
	if len(entry.LinkedPR) == 0 {
		return fmt.Errorf("changelog entry: %s has no PR id", entry.File.Name)
	}

	return nil
}

func validator_IssueNoIDs(entry Entry) error {
	if len(entry.LinkedIssue) == 0 {
		return fmt.Errorf("changelog entry: %s has no issue id", entry.File.Name)
	}

	return nil
}

func validator_componentValid(configComponents []string) entryValidationFn {
	return func(entry Entry) error {
		switch len(configComponents) {
		case 0:
			return nil
		case 1:
			c := configComponents[0]

			if c != entry.Component && len(entry.Component) > 0 {
				return fmt.Errorf("changelog entry: %s -> component [%s] not found in config: %s", entry.File.Name, entry.Component, configComponents)
			}
		default:
			var match string

			if entry.Component == "" {
				return fmt.Errorf("changelog entry: %s -> component cannot be assumed, choose it from config: %s", entry.File.Name, configComponents)
			}

			match = ""
			for _, c := range configComponents {
				if entry.Component != c {
					continue
				}
				match = entry.Component
			}

			if match == "" {
				return fmt.Errorf("changelog entry: %s -> component [%s] not found in config: %s", entry.File.Name, entry.Component, configComponents)
			}
		}

		return nil
	}
}