Move to yaml-based configuration

This commit updates the configuration to be yaml-based and updates the
configuration to read in a yaml file.

internal/config/legacy/legacy.go

@@ -0,0 +1,147 @@
+// Package legacy provides support for reading legacy configuration.
+// It is deprecated and will be removed in a future release.
+package legacy
+
+import (
+	"io"
+	"net/url"
+	"reflect"
+	"time"
+
+	"github.com/FAU-CDI/wisski-distillery/internal/config"
+	"github.com/FAU-CDI/wisski-distillery/internal/config/legacy/envreader"
+	"github.com/FAU-CDI/wisski-distillery/internal/config/legacy/stringparser"
+	"github.com/FAU-CDI/wisski-distillery/internal/config/validators"
+	"github.com/FAU-CDI/wisski-distillery/pkg/environment"
+	"github.com/pkg/errors"
+)
+
+// Migrate parses a configuration from an old configuration.
+func Migrate(config *config.Config, env environment.Environment, src io.Reader) error {
+	var legacy Legacy
+	if err := legacy.Unmarshal(env, src); err != nil {
+		return nil
+	}
+	return legacy.Migrate(config)
+}
+
+// Legacy represents a legacy configuration file.
+//
+// NOTE(twiesing): This will be deprecated soon.
+type Legacy struct {
+	DeployRoot string `env:"DEPLOY_ROOT" default:"/var/www/deploy" parser:"abspath"`
+
+	DefaultDomain string `env:"DEFAULT_DOMAIN" default:"localhost.kwarc.info" parser:"domain"`
+
+	SelfRedirect *url.URL `env:"SELF_REDIRECT" default:"https://github.com/FAU-CDI/wisski-distillery" parser:"https_url"`
+
+	SelfExtraDomains []string `env:"SELF_EXTRA_DOMAINS" default:"" parser:"domains"`
+
+	SelfOverridesFile string `env:"SELF_OVERRIDES_FILE" default:"" parser:"file"`
+
+	SelfResolverBlockFile string `env:"SELF_RESOLVER_BLOCK_FILE" default:"" parser:"file"`
+
+	CertbotEmail string `env:"CERTBOT_EMAIL" default:"" parser:"email"`
+
+	MaxBackupAge int `env:"MAX_BACKUP_AGE" default:"" parser:"number"`
+
+	MysqlUserPrefix     string `env:"MYSQL_USER_PREFIX" default:"mysql-factory-" parser:"slug"`
+	MysqlDatabasePrefix string `env:"MYSQL_DATABASE_PREFIX" default:"mysql-factory-" parser:"slug"`
+	GraphDBUserPrefix   string `env:"GRAPHDB_USER_PREFIX" default:"mysql-factory-" parser:"slug"`
+	GraphDBRepoPrefix   string `env:"GRAPHDB_REPO_PREFIX" default:"mysql-factory-" parser:"slug"`
+
+	DistilleryDatabase string `env:"DISTILLERY_BOOKKEEPING_DATABASE" default:"distillery" parser:"slug"`
+
+	PasswordLength int `env:"PASSWORD_LENGTH" default:"64" parser:"number"`
+
+	PublicSSHPort uint16 `env:"SSH_PORT" default:"2222" parser:"port"`
+
+	TriplestoreAdminUser     string `env:"GRAPHDB_ADMIN_USER" default:"admin" parser:"nonempty"`
+	TriplestoreAdminPassword string `env:"GRAPHDB_ADMIN_PASSWORD" default:"" parser:"nonempty"`
+
+	MysqlAdminUser     string `env:"MYSQL_ADMIN_USER" default:"admin" parser:"nonempty"`
+	MysqlAdminPassword string `env:"MYSQL_ADMIN_PASSWORD" default:"" parser:"nonempty"`
+
+	SessionSecret string `env:"SESSION_SECRET" default:"" parser:"nonempty"`
+
+	// name of docker network to use
+	DockerNetworkName string        `env:"DOCKER_NETWORK_NAME" default:"distillery" parser:"nonempty"`
+	CronInterval      time.Duration `env:"CRON_INTERVAL" default:"10m" parser:"duration"`
+}
+
+// Migrate migrates this LegacyConfig into a new configuration.
+func (legacy *Legacy) Migrate(cfg *config.Config) error {
+	cfg.Paths.Root = legacy.DeployRoot
+	cfg.HTTP.PrimaryDomain = legacy.DefaultDomain
+	cfg.Theme.SelfRedirect = (*validators.URL)(legacy.SelfRedirect)
+	cfg.HTTP.ExtraDomains = legacy.SelfExtraDomains
+	cfg.Paths.OverridesJSON = legacy.SelfOverridesFile
+	cfg.Paths.ResolverBlocks = legacy.SelfResolverBlockFile
+	cfg.HTTP.CertbotEmail = legacy.CertbotEmail
+	cfg.MaxBackupAge = time.Duration(legacy.MaxBackupAge) * 24 * time.Hour
+	cfg.SQL.UserPrefix = legacy.MysqlUserPrefix
+	cfg.SQL.DataPrefix = legacy.MysqlDatabasePrefix
+	cfg.TS.UserPrefix = legacy.GraphDBUserPrefix
+	cfg.TS.DataPrefix = legacy.GraphDBRepoPrefix
+	cfg.SQL.Database = legacy.DistilleryDatabase
+	cfg.PasswordLength = legacy.PasswordLength
+	cfg.PublicSSHPort = legacy.PublicSSHPort
+	cfg.TS.AdminUsername = legacy.TriplestoreAdminUser
+	cfg.TS.AdminPassword = legacy.TriplestoreAdminPassword
+	cfg.SQL.AdminUsername = legacy.MysqlAdminUser
+	cfg.SQL.AdminPassword = legacy.MysqlAdminPassword
+	cfg.SessionSecret = legacy.SessionSecret
+	cfg.Docker.Network = legacy.DockerNetworkName
+	cfg.CronInterval = legacy.CronInterval
+	return nil
+}
+
+// Unmarshal opens a legacy configuration file.
+//
+// Data is read using the [envreader.ReadAll] method, see the appropriate documentation for the file format.
+//
+// The `env` and `parser` reflect tags of the [Config] struct determine the keys to read from, and the types to expect.
+// When a key is missing, it is set to the default value.
+//
+// See also [stringparser.Parse].
+func (config *Legacy) Unmarshal(env environment.Environment, src io.Reader) error {
+	// read all the values!
+	values, err := envreader.ReadAll(src)
+	if err != nil {
+		return err
+	}
+
+	vConfig := reflect.ValueOf(config).Elem()
+	tConfig := vConfig.Type()
+
+	// iterate over the types
+	numValues := tConfig.NumField()
+	for i := 0; i < numValues; i++ {
+		tField := tConfig.Field(i)
+		vField := vConfig.FieldByName(tField.Name)
+
+		tEnv := tField.Tag.Get("env")
+		tDefault := tField.Tag.Get("default")
+		tParser := tField.Tag.Get("parser")
+
+		// skip it if it isn't loaded!
+		if tEnv == "" {
+			continue
+		}
+
+		// read the value with a default
+		value, ok := values[tEnv]
+		if !ok || value == "" {
+			if tDefault != "" {
+				value = tDefault
+			}
+		}
+
+		// parse the value!
+		if err := stringparser.Parse(env, tParser, value, vField); err != nil {
+			return errors.Errorf("Legacy.Unmarshal: Setting %q, Parser %q: %s", tEnv, tParser, err)
+		}
+	}
+
+	return nil
+}