First cut at cache management (#23)

src/MyWebLog/Caches.fs

@@ -80,6 +80,10 @@ module WebLogCache =
     let set webLog =
         _cache <- webLog :: (_cache |> List.filter (fun wl -> wl.Id <> webLog.Id))
     
+    /// Get all cached web logs
+    let all () =
+        _cache
+    
     /// Fill the web log cache from the database
     let fill (data : IData) = backgroundTask {
         let! webLogs = data.WebLog.All ()
@@ -97,22 +101,30 @@ module PageListCache =
     open MyWebLog.ViewModels
     
     /// Cache of displayed pages
-    let private _cache = ConcurrentDictionary<string, DisplayPage[]> ()
+    let private _cache = ConcurrentDictionary<WebLogId, DisplayPage[]> ()
     
-    /// Are there pages cached for this web log?
+    let private fillPages (webLog : WebLog) pages =
-    let exists (ctx : HttpContext) = _cache.ContainsKey ctx.WebLog.UrlBase
+        _cache[webLog.Id] <-
-    
-    /// Get the pages for the web log for this request
-    let get (ctx : HttpContext) = _cache[ctx.WebLog.UrlBase]
-    
-    /// Update the pages for the current web log
-    let update (ctx : HttpContext) = backgroundTask {
-        let  webLog = ctx.WebLog
-        let! pages  = ctx.Data.Page.FindListed webLog.Id
-        _cache[webLog.UrlBase] <-
             pages
             |> List.map (fun pg -> DisplayPage.fromPage webLog { pg with Text = "" })
             |> Array.ofList
+    
+    /// Are there pages cached for this web log?
+    let exists (ctx : HttpContext) = _cache.ContainsKey ctx.WebLog.Id
+    
+    /// Get the pages for the web log for this request
+    let get (ctx : HttpContext) = _cache[ctx.WebLog.Id]
+    
+    /// Update the pages for the current web log
+    let update (ctx : HttpContext) = backgroundTask {
+        let! pages = ctx.Data.Page.FindListed ctx.WebLog.Id
+        fillPages ctx.WebLog pages
+    }
+    
+    /// Refresh the pages for the given web log
+    let refresh (webLog : WebLog) (data : IData) = backgroundTask {
+        let! pages = data.Page.FindListed webLog.Id
+        fillPages webLog pages
     }
 
 
@@ -122,18 +134,24 @@ module CategoryCache =
     open MyWebLog.ViewModels
     
     /// The cache itself
-    let private _cache = ConcurrentDictionary<string, DisplayCategory[]> ()
+    let private _cache = ConcurrentDictionary<WebLogId, DisplayCategory[]> ()
     
     /// Are there categories cached for this web log?
-    let exists (ctx : HttpContext) = _cache.ContainsKey ctx.WebLog.UrlBase
+    let exists (ctx : HttpContext) = _cache.ContainsKey ctx.WebLog.Id
     
     /// Get the categories for the web log for this request
-    let get (ctx : HttpContext) = _cache[ctx.WebLog.UrlBase]
+    let get (ctx : HttpContext) = _cache[ctx.WebLog.Id]
     
     /// Update the cache with fresh data
     let update (ctx : HttpContext) = backgroundTask {
         let! cats = ctx.Data.Category.FindAllForView ctx.WebLog.Id
-        _cache[ctx.WebLog.UrlBase] <- cats
+        _cache[ctx.WebLog.Id] <- cats
+    }
+    
+    /// Refresh the category cache for the given web log
+    let refresh webLogId (data : IData) = backgroundTask {
+        let! cats = data.Category.FindAllForView webLogId
+        _cache[webLogId] <- cats
     }
 
 
@@ -168,6 +186,10 @@ module TemplateCache =
         return _cache[templatePath]
     }
     
+    /// Get all theme/template names currently cached
+    let allNames () =
+        _cache.Keys |> Seq.sort |> Seq.toList
+    
     /// Invalidate all template cache entries for the given theme ID
     let invalidateTheme (themeId : ThemeId) =
         let keyPrefix = ThemeId.toString themeId
@@ -176,6 +198,10 @@ module TemplateCache =
         |> List.ofSeq
         |> List.iter (fun key -> match _cache.TryRemove key with _, _ -> ())
     
+    /// Remove all entries from the template cache
+    let empty () =
+        _cache.Clear ()
+
 
 /// A cache of asset names by themes
 module ThemeAssetCache =

src/MyWebLog/Handlers/Admin.fs

@@ -34,12 +34,28 @@ let dashboard : HttpHandler = requireAccess Author >=> fun next ctx -> task {
 
 // GET /admin/dashboard/administration
 let adminDashboard : HttpHandler = requireAccess Administrator >=> fun next ctx -> task {
-    let! themes = ctx.Data.Theme.All ()
+    let! themes          = ctx.Data.Theme.All ()
-    let! bodyTemplate = TemplateCache.get adminTheme "theme-list-body" ctx.Data
+    let! bodyTemplate    = TemplateCache.get adminTheme "theme-list-body" ctx.Data
+    let  cachedTemplates = TemplateCache.allNames ()
     let! hash =
         hashForPage "myWebLog Administration"
         |> withAntiCsrf ctx
         |> addToHash "themes" (themes |> List.map (DisplayTheme.fromTheme WebLogCache.isThemeInUse) |> Array.ofList)
+        |> addToHash "cached_themes" (
+            themes
+            |> Seq.ofList
+            |> Seq.map (fun it -> [|
+                ThemeId.toString it.Id
+                it.Name
+                cachedTemplates |> List.filter (fun n -> n.StartsWith (ThemeId.toString it.Id)) |> List.length |> string
+            |])
+            |> Array.ofSeq)
+        |> addToHash "web_logs" (
+            WebLogCache.all ()
+            |> Seq.ofList
+            |> Seq.sortBy (fun it -> it.Name)
+            |> Seq.map (fun it -> [| WebLogId.toString it.Id; it.Name; it.UrlBase |])
+            |> Array.ofSeq)
         |> addViewContext ctx
     return!
         addToHash "theme_list" (bodyTemplate.Render hash) hash
@@ -49,6 +65,54 @@ let adminDashboard : HttpHandler = requireAccess Administrator >=> fun next ctx
 /// Redirect the user to the admin dashboard
 let toAdminDashboard : HttpHandler = redirectToGet "admin/dashboard/administration"
 
+// ~~ CACHES ~~
+
+// POST /admin/cache/web-log/{id}/refresh
+let refreshWebLogCache webLogId : HttpHandler = requireAccess Administrator >=> fun next ctx -> task {
+    let data = ctx.Data
+    if webLogId = "all" then
+        do! WebLogCache.fill data
+        for webLog in WebLogCache.all () do
+            do! PageListCache.refresh webLog    data
+            do! CategoryCache.refresh webLog.Id data
+        do! addMessage ctx { UserMessage.success with Message = "Successfully refresh web log cache for all web logs" }
+    else
+        match! data.WebLog.FindById (WebLogId webLogId) with
+        | Some webLog ->
+            WebLogCache.set webLog
+            do! PageListCache.refresh webLog    data
+            do! CategoryCache.refresh webLog.Id data
+            do! addMessage ctx
+                    { UserMessage.success with Message = $"Successfully refreshed web log cache for {webLog.Name}" }
+        | None ->
+            do! addMessage ctx { UserMessage.error with Message = $"No web log exists with ID {webLogId}" }
+    return! toAdminDashboard next ctx
+}
+
+// POST /admin/cache/theme/{id}/refresh
+let refreshThemeCache themeId : HttpHandler = requireAccess Administrator >=> fun next ctx -> task {
+    let data = ctx.Data
+    if themeId = "all" then
+        TemplateCache.empty ()
+        do! ThemeAssetCache.fill data
+        do! addMessage ctx
+                { UserMessage.success with
+                    Message = "Successfully cleared template cache and refreshed theme asset cache"
+                }
+    else
+        match! data.Theme.FindById (ThemeId themeId) with
+        | Some theme ->
+            TemplateCache.invalidateTheme    theme.Id
+            do! ThemeAssetCache.refreshTheme theme.Id data
+            do! addMessage ctx
+                    { UserMessage.success with
+                        Message = $"Successfully cleared template cache and refreshed theme asset cache for {theme.Name}"
+                    }
+        | None ->
+            do! addMessage ctx { UserMessage.error with Message = $"No theme exists with ID {themeId}" }
+    return! toAdminDashboard next ctx
+}
+
 // ~~ CATEGORIES ~~
 
 // GET /admin/categories

src/MyWebLog/Handlers/Routes.fs

@@ -157,6 +157,10 @@ let router : HttpHandler = choose [
             ])
         ]
         POST >=> validateCsrf >=> choose [
+            subRoute "/cache" (choose [
+                routef "/theme/%s/refresh"   Admin.refreshThemeCache
+                routef "/web-log/%s/refresh" Admin.refreshWebLogCache
+            ])
             subRoute "/category" (choose [
                 route  "/save"      >=> Admin.saveCategory
                 routef "/%s/delete"     Admin.deleteCategory

src/admin-theme/admin-dashboard.liquid

@@ -1,6 +1,6 @@
 <h2 class="my-3">{{ page_title }}</h2>
 <article>
-  <fieldset class="container pb-3">
+  <fieldset class="container mb-3">
     <legend>Themes</legend>
     <div class="row">
       <div class="col">
@@ -22,10 +22,90 @@
     </div>
   </fieldset>
   <fieldset class="container">
+    {%- assign cache_base_url = "admin/cache/" -%}
     <legend>Caches</legend>
-    <div class="row">
+    <div class="row pb-3">
       <div class="col">
-        TODO
+        <p>
+          myWebLog uses a few caches to ensure that it serves pages as fast as possible. Normal actions taken within the
+          admin area will keep these up to date; however, if changes occur outside of the system (creating a new web log
+          via CLI, loading an updated theme via CLI, direct data updates, etc.), these options allow for the caches to
+          be refreshed without requiring you to restart the application.
+        </p>
+      </div>
+    </div>
+    <div class="row">
+      <div class="col-12 col-lg-6 pb-3">
+        <div class="card">
+          <header class="card-header text-white bg-secondary">Web Logs</header>
+          <div class="card-body">
+            <h6 class="card-subtitle text-muted pb-3">
+              These caches include the page list and categories for each web log
+            </h6>
+            {%- assign web_log_base_url = cache_base_url | append: "web-log/" -%}
+            <form method="post" class="container pb-3" hx-boost="false" hx-target="body" hx-swap="innerHTML show:window:top">
+              <input type="hidden" name="{{ csrf.form_field_name }}" value="{{ csrf.request_token }}">
+              <button type="submit" class="btn btn-sm btn-primary pb-2"
+                      hx-post="{{ web_log_base_url | append: "all/refresh" | relative_link }}">
+                Refresh All
+              </button>
+              <div class="row mwl-table-heading">
+                <div class="col">Name</div>
+                <div class="col">URL Base</div>
+              </div>
+              {%- for web_log in web_logs %}
+                <div class="row mwl-table-detail">
+                  <div class="col">
+                    {{ web_log[1] }}<br>
+                    <small>
+                      {%- assign refresh_url = web_log_base_url | append: web_log[0] | append: "/refresh" | relative_link -%}
+                      <a href="{{ refresh_url }}" hx-post="{{ refresh_url }}">Refresh</a>
+                    </small>
+                  </div>
+                  <div class="col">{{ web_log[2] }}</div>
+                </div>
+              {%- endfor %}
+            </form>
+          </div>
+        </div>
+      </div>
+      <div class="col-12 col-lg-6 pb-3">
+        <div class="card">
+          <header class="card-header text-white bg-secondary">Themes</header>
+          <div class="card-body">
+            <h6 class="card-subtitle text-muted pb-3">
+              The themes template cache is loaded on demand; refresh a cache with 0 templates will still refresh the
+              theme asset cache
+            </h6>
+            {%- assign theme_base_url = cache_base_url | append: "theme/" -%}
+            <form method="post" class="container pb-3" hx-boost="false" hx-target="body" hx-swap="innerHTML show:window:top">
+              <input type="hidden" name="{{ csrf.form_field_name }}" value="{{ csrf.request_token }}">
+              <button type="submit" class="btn btn-sm btn-primary pb-2"
+                      hx-post="{{ theme_base_url | append: "all/refresh" | relative_link }}">
+                Refresh All
+              </button>
+              <div class="row mwl-table-heading">
+                <div class="col-8">Name</div>
+                <div class="col-4">Cached Templates</div>
+              </div>
+              {%- for theme in cached_themes %}
+                {% unless theme[0] == "admin" %}
+                  <div class="row mwl-table-detail">
+                    <div class="col-8">
+                      {{ theme[1] }}<br>
+                      <small>
+                        <span class="text-muted">{{ theme[0] }} &bull; </span>
+                        {%- assign refresh_url = theme_base_url | append: theme[0] | append: "/refresh" | relative_link -%}
+                        <a href="{{ refresh_url }}" hx-post="{{ refresh_url }}">Refresh</a>
+                      </small>
+                    </div>
+                    <div class="col-4">{{ theme[2] }}</div>
+                  </div>
+                {% endunless %}
+              {%- endfor %}
+            </form>
+          </div>
+        </div>
       </div>
     </div>
   </fieldset>