Hide plugin pages from nav when plugin is disabled

- Remove PageTypeResearch constant (now plugin-defined)
- Mark ScholarID on Page as deprecated (kept for migration compat)
- Add PageFilter to Blog struct, applied in GetNavPages to filter
  out pages owned by disabled plugins
- Add IsPageTypeEnabled to registry for checking if the plugin that
  owns a page type is enabled
- Wire up the filter in goblog.go after registry init
- Update seed defaults and tests to use string literal "research"

When the scholar plugin is disabled:
- Research page disappears from navigation
- Visiting /research shows "Page Not Available" 404
When re-enabled, everything comes back automatically.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: compscidr

blog/blog.go

@@ -24,12 +24,17 @@ import (
 	"github.com/ikeikeikeike/go-sitemap-generator/v2/stm"
 )
 
+// PageFilter is a function that decides whether a page should be shown.
+// Used to filter out pages owned by disabled plugins.
+type PageFilter func(page Page) bool
+
 // Blog API handles non-admin functions of the blog like listing posts, tags
 // comments, etc.
 type Blog struct {
 	db             **gorm.DB // needs a double pointer to be able to update the db
 	auth           auth.IAuth
 	Version        string
+	PageFilter     PageFilter // optional filter set by plugin system
 	commentLimiter map[string]time.Time
 	limiterMu      sync.Mutex
 }
@@ -354,9 +359,19 @@ func (b *Blog) TrackReferer(c *gin.Context, postID uint) {
 	}
 }
 // GetNavPages returns enabled pages that should show in the navigation, ordered by nav_order.
+// Pages owned by disabled plugins are filtered out.
 func (b *Blog) GetNavPages() []Page {
 	var pages []Page
 	(*b.db).Where("enabled = ? AND show_in_nav = ?", true, true).Order("nav_order asc").Find(&pages)
+	if b.PageFilter != nil {
+		var filtered []Page
+		for _, p := range pages {
+			if b.PageFilter(p) {
+				filtered = append(filtered, p)
+			}
+		}
+		return filtered
+	}
 	return pages
 }
 

blog/blog_test.go

@@ -197,7 +197,7 @@ func TestBlogWorkflow(t *testing.T) {
 
 	// Create pages so dynamic page resolution works
 	writingPage := blog.Page{Title: "Writing", Slug: "posts", PageType: blog.PageTypeWriting, ShowInNav: true, NavOrder: 1, Enabled: true}
-	researchPage := blog.Page{Title: "Research", Slug: "research", PageType: blog.PageTypeResearch, ShowInNav: true, NavOrder: 2, Enabled: true, ScholarID: "SbUmSEAAAAAJ"}
+	researchPage := blog.Page{Title: "Research", Slug: "research", PageType: "research", ShowInNav: true, NavOrder: 2, Enabled: true}
 	aboutPage := blog.Page{Title: "About", Slug: "about", PageType: blog.PageTypeAbout, ShowInNav: true, NavOrder: 3, Enabled: true, Content: "About page content"}
 	tagsPage := blog.Page{Title: "Tags", Slug: "tags", PageType: blog.PageTypeTags, ShowInNav: false, NavOrder: 4, Enabled: true}
 	archivesPage := blog.Page{Title: "Archives", Slug: "archives", PageType: blog.PageTypeArchives, ShowInNav: false, NavOrder: 5, Enabled: true}

blog/page.go

@@ -5,7 +5,6 @@ import "time"
 // Page types
 const (
 	PageTypeWriting  = "writing"
-	PageTypeResearch = "research"
 	PageTypeAbout    = "about"
 	PageTypeCustom   = "custom"
 	PageTypeTags     = "tags"
@@ -23,11 +22,11 @@ type Page struct {
 	Content   string     `sql:"type:text;" json:"content"`
 	HeroURL   string     `json:"hero_url"`
 	HeroType  string     `json:"hero_type"` // "image" or "video"
-	PageType  string     `json:"page_type"` // "writing", "research", "about", "custom"
+	PageType  string     `json:"page_type"` // "writing", "research", "about", "custom", or plugin-defined
 	ShowInNav bool       `json:"show_in_nav"`
 	NavOrder  int        `json:"nav_order"`
 	Enabled   bool       `json:"enabled"`
-	ScholarID  string `json:"scholar_id,omitempty"`
+	ScholarID  string `json:"scholar_id,omitempty"` // deprecated: use scholar plugin settings instead
 	PostTypeID *uint  `json:"post_type_id,omitempty"`
 }
 

goblog.go

@@ -319,6 +319,14 @@ func main() {
 		registry.StartScheduledJobs()
 	}
 
+	// Filter nav pages: hide pages owned by disabled plugins
+	_blog.PageFilter = func(page blog.Page) bool {
+		if !registry.HasPageType(page.PageType) {
+			return true // not a plugin page, always show
+		}
+		return registry.IsPageTypeEnabled(page.PageType)
+	}
+
 	router.Use(CORS())
 	router.Use(gplugin.Middleware(registry))
 	store := cookie.NewStore([]byte(sessionKey))

plugin/registry.go

@@ -237,6 +237,20 @@ func (r *Registry) GetNavItems() []PageDefinition {
 	return items
 }
 
+// IsPageTypeEnabled returns true if the plugin that owns the given page type is enabled.
+func (r *Registry) IsPageTypeEnabled(pageType string) bool {
+	r.mu.RLock()
+	defer r.mu.RUnlock()
+	for _, p := range r.plugins {
+		for _, page := range p.Pages() {
+			if page.PageType == pageType {
+				return r.IsPluginEnabled(p.Name())
+			}
+		}
+	}
+	return false
+}
+
 // HasPageType returns true if any registered plugin (enabled or not) defines the given page type.
 func (r *Registry) HasPageType(pageType string) bool {
 	r.mu.RLock()

tools/migrate.go

@@ -483,7 +483,7 @@ I also enjoy driving, working on cars, video games, contributing to [open source
 			Slug:      "research",
 			HeroURL:   "/img/aidecentralized.jpg",
 			HeroType:  "image",
-			PageType:  blog.PageTypeResearch,
+			PageType:  "research", // owned by scholar plugin
 			ShowInNav: true,
 			NavOrder:  2,
 			Enabled:   true,