Store a target's settings as columns (closes #543)

A target's settings move from the per-type JSON string in
targets.config to columns: url, headers, timeout_seconds,
forward_query, archive_expiry and archive_rotation. A column a type
does not use stays empty. headers holds the header map as JSON text
through GORM's JSON serializer, and archive_expiry holds a
time.Duration, 0 meaning never. The forms check each setting once,
with the same refusals and messages, and the edit form is filled from
the columns, so the per-type config structs, their parsers and the
"could not be read" branches are gone. A delivery task carries the
six settings in place of the JSON string; tests check that each copy
into a task, and back out of one, keeps all six.

Model: opus-5-5

internal/delivery/target_config_view.go

@@ -9,16 +9,17 @@ import (
 	"sneak.berlin/go/webhooker/internal/database"
 )
 
-// configUnavailable is what a target's configuration renders
-// as when it is absent, of an unknown type, or does not
-// parse. The stored blob is never shown as a fallback: it can
-// hold a credential (a Slack incoming webhook URL is a bearer
-// token) and a UI that prints it leaks that credential into
-// browser history, screenshots and screen shares.
+// configUnavailable is what a target's settings render as when
+// the target is of an unknown type, and what its URL renders as
+// when it does not parse into a scheme and host. The stored URL is
+// never shown as a fallback: it can be a credential (a Slack
+// incoming webhook URL is a bearer token) and a UI that prints it
+// leaks that credential into browser history, screenshots and
+// screen shares.
 const configUnavailable = "(unavailable)"
 
 // ConfigField is one labelled, display-safe value derived
-// from a target's stored configuration.
+// from a target's settings.
 type ConfigField struct {
 	Label string
 	Value string
@@ -32,9 +33,9 @@ type ConfigField struct {
 const deletedNameSuffix = " (deleted)"
 
 // TargetView is the display-safe projection of a target for
-// the UI. It deliberately has no raw configuration field, so
-// no template — present or future — can render the stored
-// blob.
+// the UI. It deliberately has no URL or header field, so no
+// template — present or future — can render the stored
+// credential.
 type TargetView struct {
 	ID   string
 	Name string
@@ -61,8 +62,7 @@ func (v TargetView) DisplayName() string {
 }
 
 // NewTargetViews projects targets for rendering, replacing
-// each stored configuration blob with named, display-safe
-// fields.
+// each target's settings with named, display-safe fields.
 //
 // A soft-deleted row projects exactly as a live one does, minus
 // the deleted marker on its name: masking is a property of the
@@ -91,8 +91,8 @@ func NewTargetViews(
 }
 
 // targetConfigFields returns the display-safe fields for a
-// target's configuration. Anything it cannot parse becomes
-// the neutral placeholder.
+// target's settings. A target of an unknown type gets the
+// neutral placeholder.
 func targetConfigFields(
 	t *database.Target,
 ) []ConfigField {
@@ -102,36 +102,25 @@ func targetConfigFields(
 	case database.TargetTypeHTTP:
 		return httpConfigFields(t)
 	case database.TargetTypeDatabase:
-		return databaseConfigFields(t.Config)
+		return databaseConfigFields(t)
 	case database.TargetTypeLog:
-		// The log target takes no configuration.
+		// The log target takes no settings.
 		return nil
 	default:
-		return unavailableConfigFields()
+		return []ConfigField{{
+			Label: "Configuration",
+			Value: configUnavailable,
+		}}
 	}
 }
 
-// unavailableConfigFields is the neutral placeholder shown
-// for a configuration that could not be presented.
-func unavailableConfigFields() []ConfigField {
-	return []ConfigField{{
-		Label: "Configuration",
-		Value: configUnavailable,
-	}}
-}
-
 // slackConfigFields describes a Slack target: its masked
 // webhook URL and its number of delivery attempts. Only the
 // masked URL is shown; the full URL is the credential.
 func slackConfigFields(t *database.Target) []ConfigField {
-	cfg, err := parseSlackConfig(t.Config)
-	if err != nil {
-		return unavailableConfigFields()
-	}
-
 	return []ConfigField{{
 		Label: "Webhook URL",
-		Value: cfg.MaskedWebhookURL(),
+		Value: MaskURL(t.URL),
 	}, maxAttemptsField(t)}
 }
 
@@ -146,33 +135,28 @@ func slackConfigFields(t *database.Target) []ConfigField {
 // whose path segments are the credential, and the field takes
 // an arbitrary URL, so no segment can be assumed non-secret.
 func httpConfigFields(t *database.Target) []ConfigField {
-	cfg, err := parseHTTPConfig(t.Config)
-	if err != nil {
-		return unavailableConfigFields()
-	}
-
 	fields := []ConfigField{{
 		Label: "Destination URL",
-		Value: MaskURL(cfg.URL),
+		Value: MaskURL(t.URL),
 	}}
 
-	if cfg.Timeout > 0 {
+	if t.TimeoutSeconds > 0 {
 		fields = append(fields, ConfigField{
 			Label: "Timeout",
-			Value: strconv.Itoa(cfg.Timeout) + "s",
+			Value: strconv.Itoa(t.TimeoutSeconds) + "s",
 		})
 	}
 
-	if len(cfg.Headers) > 0 {
+	if len(t.Headers) > 0 {
 		fields = append(fields, ConfigField{
 			Label: "Headers",
 			Value: fmt.Sprintf(
-				"%d configured", len(cfg.Headers),
+				"%d configured", len(t.Headers),
 			),
 		})
 	}
 
-	if cfg.ForwardQuery {
+	if t.ForwardQuery {
 		fields = append(fields, ConfigField{
 			Label: "Query string",
 			Value: "passed on to this target",
@@ -185,8 +169,7 @@ func httpConfigFields(t *database.Target) []ConfigField {
 }
 
 // maxAttemptsField describes a target's number of delivery
-// attempts, which lives on the target row rather than in its
-// configuration blob.
+// attempts.
 func maxAttemptsField(t *database.Target) ConfigField {
 	return ConfigField{
 		Label: "Delivery attempts",
@@ -196,24 +179,11 @@ func maxAttemptsField(t *database.Target) ConfigField {
 
 // databaseConfigFields describes an archive target by its
 // expiry in plain units, such as "30 days", or "never" when
-// the archive is kept forever, and by its rotation. An expiry
-// that is set but not a valid duration, or a rotation that is
-// not one of the four, is reported as unavailable rather than
-// echoed back.
-func databaseConfigFields(configJSON string) []ConfigField {
-	expiry, err := archive.ParseExpiry(configJSON)
-	if err != nil {
-		return unavailableConfigFields()
-	}
-
-	rotation, err := archive.ParseRotation(configJSON)
-	if err != nil {
-		return unavailableConfigFields()
-	}
-
+// the archive is kept forever, and by its rotation.
+func databaseConfigFields(t *database.Target) []ConfigField {
 	value := archive.ExpiryNever
-	if expiry > 0 {
-		value = plainDuration(expiry)
+	if t.ArchiveExpiry > 0 {
+		value = plainDuration(t.ArchiveExpiry)
 	}
 
 	return []ConfigField{{
@@ -221,7 +191,7 @@ func databaseConfigFields(configJSON string) []ConfigField {
 		Value: value,
 	}, {
 		Label: "Archive rotation",
-		Value: rotation,
+		Value: t.ArchiveRotation,
 	}}
 }
 
@@ -257,14 +227,3 @@ func plainDuration(d time.Duration) string {
 
 	return d.String()
 }
-
-// MaskedWebhookURL returns the Slack webhook URL reduced to
-// its scheme and host, with the path, query and any userinfo
-// elided. The path segments are the credential, so none of
-// them is shown: the field accepts an arbitrary URL, so no
-// segment can be assumed non-secret. A URL that does not
-// parse into a scheme and host yields the neutral
-// placeholder, never the raw string.
-func (c *SlackTargetConfig) MaskedWebhookURL() string {
-	return MaskURL(c.WebhookURL)
-}