knowledge-governance/internal/httpapi/routing_bindings.go

package httpapi

import (
	"context"
	"net/http"
	"strings"

	"knowledge-governance/internal/platform/weknora"
)

// RoutingBindingStore persists the UI-managed knowledge base bindings
// (migration 000034). Empty stored values fall back to env defaults.
type RoutingBindingStore interface {
	LoadRoutingKBBindings(context.Context) (string, string, string, error)
	SaveRoutingKBBindings(context.Context, string, string, string) error
}

// KnowledgeBaseLister enumerates candidate knowledge bases in the connected
// WeKnora so the settings page offers a picker instead of raw UUIDs.
type KnowledgeBaseLister interface {
	ListKnowledgeBases(context.Context) ([]weknora.KnowledgeBase, error)
}

type routingBindingView struct {
	InternalKBID        string `json:"internal_kb_id"`
	ExternalKBID        string `json:"external_kb_id"`
	InternalEnvFallback bool   `json:"internal_env_fallback"`
	ExternalEnvFallback bool   `json:"external_env_fallback"`
	InternalBoundByUI   bool   `json:"internal_bound_by_ui"`
	ExternalBoundByUI   bool   `json:"external_bound_by_ui"`
	InternalKBName      string `json:"internal_kb_name"`
	ExternalKBName      string `json:"external_kb_name"`
	UpdatedBy           string `json:"updated_by"`
	WeKnoraConnected    bool   `json:"weknora_connected"`
}

type routingKnowledgeBaseOption struct {
	ID             string `json:"id"`
	Name           string `json:"name"`
	KnowledgeCount int64  `json:"knowledge_count"`
}

// effectiveRoutingTargets resolves (internal, external) WeKnora knowledge
// base ids for this request: UI bindings win, environment defaults fill the
// unbound side. Load failures behave as "unbound" (fail toward env, never
// toward a half-configured new target).
func (config Config) effectiveRoutingTargets(ctx context.Context) (string, string) {
	internal, external := config.InternalRoutingKnowledgeBaseID, config.ExternalRoutingKnowledgeBaseID
	if config.RoutingBindings == nil {
		return internal, external
	}
	storedInternal, storedExternal, _, err := config.RoutingBindings.LoadRoutingKBBindings(ctx)
	if err != nil {
		return internal, external
	}
	if storedInternal != "" {
		internal = storedInternal
	}
	if storedExternal != "" {
		external = storedExternal
	}
	return internal, external
}

func (config Config) routingBindingNames(ctx context.Context) (map[string]string, bool) {
	if config.KnowledgeBases == nil {
		return nil, false
	}
	bases, err := config.KnowledgeBases.ListKnowledgeBases(ctx)
	if err != nil {
		return nil, false
	}
	names := make(map[string]string, len(bases))
	for _, base := range bases {
		names[base.ID] = base.Name
	}
	return names, true
}

func (config Config) handleRoutingBindings(w http.ResponseWriter, r *http.Request) {
	names, connected := config.routingBindingNames(r.Context())
	storedInternal, storedExternal, updatedBy, err := config.RoutingBindings.LoadRoutingKBBindings(r.Context())
	if err != nil {
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": "could not load routing bindings"})
		return
	}
	internal, external := config.effectiveRoutingTargets(r.Context())
	view := routingBindingView{
		InternalKBID: internal, ExternalKBID: external,
		InternalBoundByUI: storedInternal != "", ExternalBoundByUI: storedExternal != "",
		InternalEnvFallback: storedInternal == "" && config.InternalRoutingKnowledgeBaseID != "",
		ExternalEnvFallback: storedExternal == "" && config.ExternalRoutingKnowledgeBaseID != "",
		InternalKBName:      names[storedInternal], ExternalKBName: names[storedExternal],
		UpdatedBy: updatedBy, WeKnoraConnected: connected,
	}
	writeJSON(w, http.StatusOK, map[string]any{"data": view})
}

func (config Config) handleRoutingKnowledgeBaseOptions(w http.ResponseWriter, r *http.Request) {
	if config.KnowledgeBases == nil {
		writeJSON(w, http.StatusServiceUnavailable, map[string]string{"error": "WeKnora connection is not configured"})
		return
	}
	bases, err := config.KnowledgeBases.ListKnowledgeBases(r.Context())
	if err != nil {
		writeJSON(w, http.StatusBadGateway, map[string]string{"error": "could not list WeKnora knowledge bases"})
		return
	}
	options := make([]routingKnowledgeBaseOption, 0, len(bases))
	for _, base := range bases {
		options = append(options, routingKnowledgeBaseOption{ID: base.ID, Name: base.Name, KnowledgeCount: base.KnowledgeCount})
	}
	writeJSON(w, http.StatusOK, map[string]any{"data": options})
}

func (config Config) handleSaveRoutingBindings(w http.ResponseWriter, r *http.Request) {
	var input struct {
		InternalKBID string `json:"internal_kb_id"`
		ExternalKBID string `json:"external_kb_id"`
	}
	if err := decodeStrictJSON(r, &input); err != nil {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "invalid request body"})
		return
	}
	internal := strings.TrimSpace(input.InternalKBID)
	external := strings.TrimSpace(input.ExternalKBID)
	for _, id := range []string{internal, external} {
		if id != "" && !validCatalogID(id) {
			writeJSON(w, http.StatusBadRequest, map[string]string{"error": "knowledge base ID is invalid"})
			return
		}
	}
	if internal != "" && internal == external {
		writeJSON(w, http.StatusBadRequest, map[string]string{"error": "对内与对外必须绑定不同的知识库"})
		return
	}
	// When WeKnora is reachable the binding must name a real knowledge base;
	// offline saves fall through to the DB so the page never hard-fails, but
	// the response reports connected=false honestly.
	names, connected := config.routingBindingNames(r.Context())
	if connected {
		if internal != "" {
			if _, ok := names[internal]; !ok {
				writeJSON(w, http.StatusBadRequest, map[string]string{"error": "对内绑定的知识库在该 WeKnora 实例中不存在"})
				return
			}
		}
		if external != "" {
			if _, ok := names[external]; !ok {
				writeJSON(w, http.StatusBadRequest, map[string]string{"error": "对外绑定的知识库在该 WeKnora 实例中不存在"})
				return
			}
		}
	}
	if err := config.RoutingBindings.SaveRoutingKBBindings(r.Context(), internal, external, actorFor(r)); err != nil {
		writeJSON(w, http.StatusInternalServerError, map[string]string{"error": "could not save routing bindings"})
		return
	}
	config.handleRoutingBindings(w, r)
}