Files
ConfigKit/examples/consumers/diff.go

137 lines
4.3 KiB
Go

package consumers
import (
"fmt"
"strconv"
"strings"
configkit "gitea.maximumdirect.net/eric/ConfigKit"
)
// FileComparisonConfig is a small application-owned shape for comparing
// caller-selected configuration files.
type FileComparisonConfig struct {
Name string `yaml:"name"`
Entries map[string]any `yaml:"entries"`
}
// CompareFiles loads two caller-selected files with the same application
// definition, then formats only the safe records returned by configkit.Diff.
func CompareFiles(leftPath, rightPath string) (string, error) {
options := configkit.Options[FileComparisonConfig]{
Definition: configkit.Definition[FileComparisonConfig]{
Defaults: func() FileComparisonConfig {
return FileComparisonConfig{Entries: map[string]any{}}
},
},
}
left, err := configkit.Load(configkit.File(leftPath), options)
if err != nil {
return "", fmt.Errorf("load left configuration: %w", err)
}
right, err := configkit.Load(configkit.File(rightPath), options)
if err != nil {
return "", fmt.Errorf("load right configuration: %w", err)
}
differences, err := configkit.Diff(left, right)
if err != nil {
return "", err
}
return FormatDifferences(differences), nil
}
// RolloutConfig models a service endpoint whose URL is derived by the
// application resolver and whose credential reference is classified.
type RolloutConfig struct {
Service RolloutService `yaml:"service"`
}
// RolloutService contains endpoint settings and a classified credential.
type RolloutService struct {
Endpoint RolloutEndpoint `yaml:"endpoint"`
Credential RolloutCredential `yaml:"credential"`
}
// RolloutEndpoint is the effective destination used by the application.
type RolloutEndpoint struct {
Host string `yaml:"host"`
Port int `yaml:"port"`
URL string `yaml:"url"`
}
// RolloutCredential holds only a typed secret reference in configuration.
type RolloutCredential struct {
Token configkit.Secret `yaml:"token" configkit:"secret"`
}
// LoadRollout loads a base file, optionally with one selected configuration
// overlay. Resolution derives the effective URL after the overlay is applied.
func LoadRollout(basePath, overlayName string) (*configkit.Result[RolloutConfig], error) {
return configkit.Load(configkit.File(basePath), configkit.Options[RolloutConfig]{
Overlay: overlayName,
Definition: configkit.Definition[RolloutConfig]{
Resolve: resolveRollout,
},
})
}
// CompareRolloutOverlay compares the effective base configuration with that
// same file plus one selected overlay. It presents only safe diff records.
func CompareRolloutOverlay(basePath, overlayName string) (string, error) {
base, err := LoadRollout(basePath, "")
if err != nil {
return "", fmt.Errorf("load base configuration: %w", err)
}
withOverlay, err := LoadRollout(basePath, overlayName)
if err != nil {
return "", fmt.Errorf("load overlay configuration: %w", err)
}
differences, err := configkit.Diff(base, withOverlay)
if err != nil {
return "", err
}
return FormatDifferences(differences), nil
}
func resolveRollout(configuration *RolloutConfig, resolution *configkit.Resolution) error {
endpoint := &configuration.Service.Endpoint
if endpoint.Host == "" || endpoint.Port <= 0 {
return nil
}
url := fmt.Sprintf("https://%s:%d", endpoint.Host, endpoint.Port)
if endpoint.URL != url {
endpoint.URL = url
resolution.Record(configkit.Keys("service", "endpoint", "url"),
configkit.ChangeNormalization, "derived endpoint URL",
configkit.Keys("service", "endpoint", "host"),
configkit.Keys("service", "endpoint", "port"))
}
return nil
}
// FormatDifferences is consumer-owned presentation. It distinguishes absence
// through Present and reports withheld changes through HiddenChanged without
// interpreting redaction marker text.
func FormatDifferences(differences []configkit.Difference) string {
if len(differences) == 0 {
return "No effective changes.\n"
}
var output strings.Builder
for _, difference := range differences {
fmt.Fprintf(&output, "%s: left=%s right=%s", difference.Path.String(),
formatSnapshot(difference.Left), formatSnapshot(difference.Right))
if difference.HiddenChanged {
output.WriteString(" hidden-change")
}
output.WriteByte('\n')
}
return output.String()
}
func formatSnapshot(snapshot configkit.ValueSnapshot) string {
if !snapshot.Present {
return "<absent>"
}
return strconv.Quote(snapshot.YAML)
}