Split handlers into individual files

- Fix 500 when viewing draft posts

src/MyWebLog.Data/MyWebLog.Data.fsproj

@@ -10,12 +10,12 @@
 	</ItemGroup>
 
 	<ItemGroup>
-		<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="*" />
+		<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="6.0.0" />
 		<PackageReference Include="Microsoft.FSharpLu.Json" Version="0.11.7" />
 		<PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
 		<PackageReference Include="RethinkDb.Driver" Version="2.3.150" />
-		<PackageReference Include="RethinkDb.Driver.FSharp" Version="0.8.0-alpha-0009" />
-		<PackageReference Update="FSharp.Core" Version="6.0.3" />
+		<PackageReference Include="RethinkDb.Driver.FSharp" Version="0.9.0-beta-01" />
+		<PackageReference Update="FSharp.Core" Version="6.0.4" />
 	</ItemGroup>
 	
 	<ItemGroup>

src/MyWebLog.Domain/MyWebLog.Domain.fsproj

@@ -13,7 +13,7 @@
 
   <ItemGroup>
     <PackageReference Include="Markdig" Version="0.30.2" />
-    <PackageReference Update="FSharp.Core" Version="6.0.3" />
+    <PackageReference Update="FSharp.Core" Version="6.0.4" />
     <PackageReference Include="Markdown.ColorCode" Version="1.0.1" />
   </ItemGroup>
 

src/MyWebLog/Handlers/Admin.fs

@@ -0,0 +1,95 @@
+/// Handlers to manipulate admin functions
+module MyWebLog.Handlers.Admin
+
+open System.Collections.Generic
+open System.IO
+
+/// The currently available themes
+let private themes () =
+    Directory.EnumerateDirectories "themes"
+    |> Seq.map (fun it -> it.Split Path.DirectorySeparatorChar |> Array.last)
+    |> Seq.filter (fun it -> it <> "admin")
+    |> Seq.map (fun it -> KeyValuePair.Create (it, it))
+    |> Array.ofSeq
+
+open System.Threading.Tasks
+open DotLiquid
+open Giraffe
+open MyWebLog
+open MyWebLog.ViewModels
+open RethinkDb.Driver.Net
+
+// GET /admin
+let dashboard : HttpHandler = requireUser >=> fun next ctx -> task {
+    let webLogId = webLogId ctx
+    let conn     = conn ctx
+    let getCount (f : WebLogId -> IConnection -> Task<int>) = f webLogId conn
+    let! posts   = Data.Post.countByStatus Published |> getCount
+    let! drafts  = Data.Post.countByStatus Draft     |> getCount
+    let! pages   = Data.Page.countAll                |> getCount
+    let! listed  = Data.Page.countListed             |> getCount
+    let! cats    = Data.Category.countAll            |> getCount
+    let! topCats = Data.Category.countTopLevel       |> getCount
+    return!
+        Hash.FromAnonymousObject
+            {| page_title = "Dashboard"
+               model =
+                   { posts              = posts
+                     drafts             = drafts
+                     pages              = pages
+                     listedPages        = listed
+                     categories         = cats
+                     topLevelCategories = topCats
+                   }
+            |}
+        |> viewForTheme "admin" "dashboard" next ctx
+}
+
+// GET /admin/settings
+let settings : HttpHandler = requireUser >=> fun next ctx -> task {
+    let  webLog   = WebLogCache.get ctx
+    let! allPages = Data.Page.findAll webLog.id (conn ctx)
+    return!
+        Hash.FromAnonymousObject
+            {|  csrf  = csrfToken ctx
+                model = SettingsModel.fromWebLog webLog
+                pages =
+                    seq {
+                        KeyValuePair.Create ("posts", "- First Page of Posts -")
+                        yield! allPages
+                               |> List.sortBy (fun p -> p.title.ToLower ())
+                               |> List.map (fun p -> KeyValuePair.Create (PageId.toString p.id, p.title))
+                    }
+                    |> Array.ofSeq
+                themes     = themes ()
+                web_log    = webLog
+                page_title = "Web Log Settings"
+            |}
+        |> viewForTheme "admin" "settings" next ctx
+}
+
+// POST /admin/settings
+let saveSettings : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let  conn  = conn ctx
+    let! model = ctx.BindFormAsync<SettingsModel> ()
+    match! Data.WebLog.findById (WebLogCache.get ctx).id conn with
+    | Some webLog ->
+        let updated =
+            { webLog with
+                name         = model.name
+                subtitle     = if model.subtitle = "" then None else Some model.subtitle
+                defaultPage  = model.defaultPage
+                postsPerPage = model.postsPerPage
+                timeZone     = model.timeZone
+                themePath    = model.themePath
+            }
+        do! Data.WebLog.updateSettings updated conn
+
+        // Update cache
+        WebLogCache.set ctx updated
+    
+        do! addMessage ctx { UserMessage.success with message = "Web log settings saved successfully" }
+        return! redirectToGet "/admin" next ctx
+    | None -> return! Error.notFound next ctx
+}
+

src/MyWebLog/Handlers/Category.fs

@@ -0,0 +1,82 @@
+/// Handlers to manipulate categories
+module MyWebLog.Handlers.Category
+
+open DotLiquid
+open Giraffe
+open MyWebLog
+
+// GET /categories
+let all : HttpHandler = requireUser >=> fun next ctx -> task {
+    return!
+        Hash.FromAnonymousObject {|
+            categories = CategoryCache.get ctx
+            page_title = "Categories"
+            csrf       = csrfToken ctx
+        |}
+        |> viewForTheme "admin" "category-list" next ctx
+}
+
+open MyWebLog.ViewModels
+
+// GET /category/{id}/edit
+let edit catId : HttpHandler = requireUser >=> fun next ctx -> task {
+    let  webLogId = webLogId ctx
+    let  conn     = conn     ctx
+    let! result   = task {
+        match catId with
+        | "new" -> return Some ("Add a New Category", { Category.empty with id = CategoryId "new" })
+        | _ ->
+            match! Data.Category.findById (CategoryId catId) webLogId conn with
+            | Some cat -> return Some ("Edit Category", cat)
+            | None -> return None
+    }
+    match result with
+    | Some (title, cat) ->
+        return!
+            Hash.FromAnonymousObject {|
+                csrf       = csrfToken ctx
+                model      = EditCategoryModel.fromCategory cat
+                page_title = title
+                categories = CategoryCache.get ctx
+            |}
+            |> viewForTheme "admin" "category-edit" next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+// POST /category/save
+let save : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let! model    = ctx.BindFormAsync<EditCategoryModel> ()
+    let  webLogId = webLogId ctx
+    let  conn     = conn     ctx
+    let! category = task {
+        match model.categoryId with
+        | "new" -> return Some { Category.empty with id = CategoryId.create (); webLogId = webLogId }
+        | catId -> return! Data.Category.findById (CategoryId catId) webLogId conn
+    }
+    match category with
+    | Some cat ->
+        let cat =
+            { cat with
+                name        = model.name
+                slug        = model.slug
+                description = if model.description = "" then None else Some model.description
+                parentId    = if model.parentId    = "" then None else Some (CategoryId model.parentId)
+            }
+        do! (match model.categoryId with "new" -> Data.Category.add | _ -> Data.Category.update) cat conn
+        do! CategoryCache.update ctx
+        do! addMessage ctx { UserMessage.success with message = "Category saved successfully" }
+        return! redirectToGet $"/category/{CategoryId.toString cat.id}/edit" next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+// POST /category/{id}/delete
+let delete catId : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let webLogId = webLogId ctx
+    let conn     = conn     ctx
+    match! Data.Category.delete (CategoryId catId) webLogId conn with
+    | true ->
+        do! CategoryCache.update ctx
+        do! addMessage ctx { UserMessage.success with message = "Category deleted successfully" }
+    | false -> do! addMessage ctx { UserMessage.error with message = "Category not found; cannot delete" }
+    return! redirectToGet "/categories" next ctx
+}

src/MyWebLog/Handlers/Error.fs

@@ -0,0 +1,18 @@
+/// Handlers for error conditions
+module MyWebLog.Handlers.Error
+
+open System.Net
+open System.Threading.Tasks
+open Microsoft.AspNetCore.Http
+open Giraffe
+
+/// Handle unauthorized actions, redirecting to log on for GETs, otherwise returning a 401 Not Authorized response
+let notAuthorized : HttpHandler = fun next ctx ->
+    (next, ctx)
+    ||> match ctx.Request.Method with
+        | "GET" -> redirectTo false $"/user/log-on?returnUrl={WebUtility.UrlEncode ctx.Request.Path}"
+        | _ -> setStatusCode 401 >=> fun _ _ -> Task.FromResult<HttpContext option> None
+
+/// Handle 404s from the API, sending known URL paths to the Vue app so that they can be handled there
+let notFound : HttpHandler =
+    setStatusCode 404 >=> text "Not found"

src/MyWebLog/Handlers/Helpers.fs

@@ -0,0 +1,171 @@
+[<AutoOpen>]
+module private MyWebLog.Handlers.Helpers
+
+open System.Text.Json
+open Microsoft.AspNetCore.Http
+
+/// Session extensions to get and set objects
+type ISession with
+    
+    /// Set an item in the session
+    member this.Set<'T> (key, item : 'T) =
+        this.SetString (key, JsonSerializer.Serialize item)
+    
+    /// Get an item from the session
+    member this.Get<'T> key =
+        match this.GetString key with
+        | null -> None
+        | item -> Some (JsonSerializer.Deserialize<'T> item)
+
+    
+/// The HTTP item key for loading the session
+let private sessionLoadedKey = "session-loaded"
+
+/// Load the session if it has not been loaded already; ensures async access but not excessive loading
+let private loadSession (ctx : HttpContext) = task {
+    if not (ctx.Items.ContainsKey sessionLoadedKey) then
+        do! ctx.Session.LoadAsync ()
+        ctx.Items.Add (sessionLoadedKey, "yes")
+}
+
+/// Ensure that the session is committed
+let private commitSession (ctx : HttpContext) = task {
+    if ctx.Items.ContainsKey sessionLoadedKey then do! ctx.Session.CommitAsync ()
+}
+
+open MyWebLog.ViewModels
+
+/// Add a message to the user's session
+let addMessage (ctx : HttpContext) message = task {
+    do! loadSession ctx
+    let msg = match ctx.Session.Get<UserMessage list> "messages" with Some it -> it | None -> []
+    ctx.Session.Set ("messages", message :: msg)
+}
+
+/// Get any messages from the user's session, removing them in the process
+let messages (ctx : HttpContext) = task {
+    do! loadSession ctx
+    match ctx.Session.Get<UserMessage list> "messages" with
+    | Some msg ->
+        ctx.Session.Remove "messages"
+        return msg |> (List.rev >> Array.ofList)
+    | None -> return [||]
+}
+
+/// Hold variable for the configured generator string
+let mutable private generatorString : string option = None
+
+open Microsoft.Extensions.Configuration
+open Microsoft.Extensions.DependencyInjection
+
+/// Get the generator string
+let generator (ctx : HttpContext) =
+    match generatorString with
+    | Some gen -> gen
+    | None ->
+        let cfg = ctx.RequestServices.GetRequiredService<IConfiguration> ()
+        generatorString <- Option.ofObj cfg["Generator"]
+        defaultArg generatorString "generator not configured"
+
+open DotLiquid
+open MyWebLog
+
+/// Either get the web log from the hash, or get it from the cache and add it to the hash
+let private deriveWebLogFromHash (hash : Hash) ctx =
+    match hash.ContainsKey "web_log" with
+    | true -> hash["web_log"] :?> WebLog
+    | false ->
+        let wl = WebLogCache.get ctx
+        hash.Add ("web_log", wl)
+        wl
+
+open Giraffe
+
+/// Render a view for the specified theme, using the specified template, layout, and hash
+let viewForTheme theme template next ctx = fun (hash : Hash) -> task {
+    // Don't need the web log, but this adds it to the hash if the function is called directly
+    let _ = deriveWebLogFromHash hash ctx
+    let! messages = messages ctx
+    hash.Add ("logged_on",    ctx.User.Identity.IsAuthenticated)
+    hash.Add ("page_list",    PageListCache.get ctx)
+    hash.Add ("current_page", ctx.Request.Path.Value.Substring 1)
+    hash.Add ("messages",     messages)
+    hash.Add ("generator",    generator ctx)
+    
+    do! commitSession ctx
+    
+    // NOTE: DotLiquid does not support {% render %} or {% include %} in its templates, so we will do a 2-pass render;
+    //       the net effect is a "layout" capability similar to Razor or Pug
+    
+    // Render view content...
+    let! contentTemplate = TemplateCache.get theme template
+    hash.Add ("content", contentTemplate.Render hash)
+    
+    // ...then render that content with its layout
+    let! layoutTemplate = TemplateCache.get theme "layout"
+    
+    return! htmlString (layoutTemplate.Render hash) next ctx
+}
+
+/// Return a view for the web log's default theme
+let themedView template next ctx = fun (hash : Hash) -> task {
+    return! viewForTheme (deriveWebLogFromHash hash ctx).themePath template next ctx hash
+}
+
+/// Redirect after doing some action; commits session and issues a temporary redirect
+let redirectToGet url : HttpHandler = fun next ctx -> task {
+    do! commitSession ctx
+    return! redirectTo false url next ctx
+}
+
+/// Get the web log ID for the current request
+let webLogId ctx = (WebLogCache.get ctx).id
+
+open System.Security.Claims
+
+/// Get the user ID for the current request
+let userId (ctx : HttpContext) =
+    WebLogUserId (ctx.User.Claims |> Seq.find (fun c -> c.Type = ClaimTypes.NameIdentifier)).Value
+
+open RethinkDb.Driver.Net
+
+/// Get the RethinkDB connection
+let conn (ctx : HttpContext) = ctx.RequestServices.GetRequiredService<IConnection> ()
+
+open Microsoft.AspNetCore.Antiforgery
+
+/// Get the Anti-CSRF service
+let private antiForgery (ctx : HttpContext) = ctx.RequestServices.GetRequiredService<IAntiforgery> ()
+
+/// Get the cross-site request forgery token set
+let csrfToken (ctx : HttpContext) =
+    (antiForgery ctx).GetAndStoreTokens ctx
+
+/// Validate the cross-site request forgery token in the current request
+let validateCsrf : HttpHandler = fun next ctx -> task {
+    match! (antiForgery ctx).IsRequestValidAsync ctx with
+    | true -> return! next ctx
+    | false -> return! RequestErrors.BAD_REQUEST "CSRF token invalid" next ctx
+}
+
+/// Require a user to be logged on
+let requireUser : HttpHandler = requiresAuthentication Error.notAuthorized
+
+open System.Collections.Generic
+open System.IO
+
+/// Get the templates available for the current web log's theme (in a key/value pair list)
+let templatesForTheme ctx (typ : string) =
+    seq {
+        KeyValuePair.Create ("", $"- Default (single-{typ}) -")
+        yield!
+            Path.Combine ("themes", (WebLogCache.get ctx).themePath)
+            |> Directory.EnumerateFiles
+            |> Seq.filter (fun it -> it.EndsWith $"{typ}.liquid")
+            |> Seq.map (fun it ->
+                let parts    = it.Split Path.DirectorySeparatorChar
+                let template = parts[parts.Length - 1].Replace (".liquid", "")
+                KeyValuePair.Create (template, template))
+    }
+    |> Array.ofSeq
+

src/MyWebLog/Handlers/Page.fs

@@ -0,0 +1,100 @@
+/// Handlers to manipulate pages
+module MyWebLog.Handlers.Page
+
+open DotLiquid
+open Giraffe
+open MyWebLog
+open MyWebLog.ViewModels
+
+// GET /pages
+// GET /pages/page/{pageNbr}
+let all pageNbr : HttpHandler = requireUser >=> fun next ctx -> task {
+    let  webLog = WebLogCache.get ctx
+    let! pages  = Data.Page.findPageOfPages webLog.id pageNbr (conn ctx)
+    return!
+        Hash.FromAnonymousObject
+            {| pages      = pages |> List.map (DisplayPage.fromPageMinimal webLog)
+               page_title = "Pages"
+            |}
+        |> viewForTheme "admin" "page-list" next ctx
+}
+
+// GET /page/{id}/edit
+let edit pgId : HttpHandler = requireUser >=> fun next ctx -> task {
+    let! result = task {
+        match pgId with
+        | "new" -> return Some ("Add a New Page", { Page.empty with id = PageId "new" })
+        | _ ->
+            match! Data.Page.findByFullId (PageId pgId) (webLogId ctx) (conn ctx) with
+            | Some page -> return Some ("Edit Page", page)
+            | None -> return None
+    }
+    match result with
+    | Some (title, page) ->
+        let model = EditPageModel.fromPage page
+        return!
+            Hash.FromAnonymousObject {|
+                csrf       = csrfToken ctx
+                model      = model
+                metadata   = Array.zip model.metaNames model.metaValues
+                             |> Array.mapi (fun idx (name, value) -> [| string idx; name; value |])
+                page_title = title
+                templates  = templatesForTheme ctx "page"
+            |}
+            |> viewForTheme "admin" "page-edit" next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+open System
+
+// POST /page/save
+let save : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let! model    = ctx.BindFormAsync<EditPageModel> ()
+    let  webLogId = webLogId ctx
+    let  conn     = conn ctx
+    let  now      = DateTime.UtcNow
+    let! pg       = task {
+        match model.pageId with
+        | "new" ->
+            return Some
+                { Page.empty with
+                    id          = PageId.create ()
+                    webLogId    = webLogId
+                    authorId    = userId ctx
+                    publishedOn = now
+                }
+        | pgId -> return! Data.Page.findByFullId (PageId pgId) webLogId conn
+    }
+    match pg with
+    | Some page ->
+        let updateList = page.showInPageList <> model.isShownInPageList
+        let revision   = { asOf = now; text = MarkupText.parse $"{model.source}: {model.text}" }
+        // Detect a permalink change, and add the prior one to the prior list
+        let page =
+            match Permalink.toString page.permalink with
+            | "" -> page
+            | link when link = model.permalink -> page
+            | _ -> { page with priorPermalinks = page.permalink :: page.priorPermalinks }
+        let page =
+            { page with
+                title          = model.title
+                permalink      = Permalink model.permalink
+                updatedOn      = now
+                showInPageList = model.isShownInPageList
+                template       = match model.template with "" -> None | tmpl -> Some tmpl
+                text           = MarkupText.toHtml revision.text
+                metadata       = Seq.zip model.metaNames model.metaValues
+                                 |> Seq.filter (fun it -> fst it > "")
+                                 |> Seq.map (fun it -> { name = fst it; value = snd it })
+                                 |> Seq.sortBy (fun it -> $"{it.name.ToLower ()} {it.value.ToLower ()}")
+                                 |> List.ofSeq
+                revisions      = match page.revisions |> List.tryHead with
+                                 | Some r when r.text = revision.text -> page.revisions
+                                 | _ -> revision :: page.revisions
+            }
+        do! (match model.pageId with "new" -> Data.Page.add | _ -> Data.Page.update) page conn
+        if updateList then do! PageListCache.update ctx
+        do! addMessage ctx { UserMessage.success with message = "Page saved successfully" }
+        return! redirectToGet $"/page/{PageId.toString page.id}/edit" next ctx
+    | None -> return! Error.notFound next ctx
+}

src/MyWebLog/Handlers/Post.fs

@@ -0,0 +1,397 @@
+/// Handlers to manipulate posts
+module MyWebLog.Handlers.Post
+
+open System
+open Giraffe
+open Microsoft.AspNetCore.Http
+
+/// Split the "rest" capture for categories and tags into the page number and category/tag URL parts
+let private pathAndPageNumber (ctx : HttpContext) =
+    let slugs     = (string ctx.Request.RouteValues["slug"]).Split "/" |> Array.filter (fun it -> it <> "")
+    let pageIdx   = Array.IndexOf (slugs, "page")
+    let pageNbr   = if pageIdx > 0 then (int64 slugs[pageIdx + 1]) else 1L
+    let slugParts = if pageIdx > 0 then Array.truncate pageIdx slugs else slugs
+    pageNbr, String.Join ("/", slugParts)
+    
+/// The type of post list being prepared
+type ListType =
+    | AdminList
+    | CategoryList
+    | PostList
+    | SinglePost
+    | TagList
+
+open MyWebLog
+
+/// Get all authors for a list of posts as metadata items
+let private getAuthors (webLog : WebLog) (posts : Post list) conn =
+    posts
+    |> List.map (fun p -> p.authorId)
+    |> List.distinct
+    |> Data.WebLogUser.findNames webLog.id conn
+
+open System.Threading.Tasks
+open DotLiquid
+open MyWebLog.ViewModels
+
+/// Convert a list of posts into items ready to be displayed
+let private preparePostList webLog posts listType url pageNbr perPage ctx conn = task {
+    let! authors = getAuthors webLog posts conn
+    let postItems =
+        posts
+        |> Seq.ofList
+        |> Seq.truncate perPage
+        |> Seq.map (PostListItem.fromPost webLog)
+        |> Array.ofSeq
+    let! olderPost, newerPost =
+        match listType with
+        | SinglePost ->
+            let post     = List.head posts
+            let dateTime = defaultArg post.publishedOn post.updatedOn
+            Data.Post.findSurroundingPosts webLog.id dateTime conn
+        | _ -> Task.FromResult (None, None)
+    let newerLink =
+        match listType, pageNbr with
+        | SinglePost,   _  -> newerPost |> Option.map (fun p -> Permalink.toString p.permalink)
+        | _,            1L -> None
+        | PostList,     2L    when webLog.defaultPage = "posts" -> Some ""
+        | PostList,     _  -> Some $"page/{pageNbr - 1L}"
+        | CategoryList, 2L -> Some $"category/{url}/"
+        | CategoryList, _  -> Some $"category/{url}/page/{pageNbr - 1L}"
+        | TagList,      2L -> Some $"tag/{url}/"
+        | TagList,      _  -> Some $"tag/{url}/page/{pageNbr - 1L}"
+        | AdminList,    2L -> Some "posts"
+        | AdminList,    _  -> Some $"posts/page/{pageNbr - 1L}"
+    let olderLink =
+        match listType, List.length posts > perPage with
+        | SinglePost,   _     -> olderPost |> Option.map (fun p -> Permalink.toString p.permalink)
+        | _,            false -> None
+        | PostList,     true  -> Some $"page/{pageNbr + 1L}"
+        | CategoryList, true  -> Some $"category/{url}/page/{pageNbr + 1L}"
+        | TagList,      true  -> Some $"tag/{url}/page/{pageNbr + 1L}"
+        | AdminList,    true  -> Some $"posts/page/{pageNbr + 1L}"
+    let model =
+        { posts      = postItems
+          authors    = authors
+          subtitle   = None
+          newerLink  = newerLink
+          newerName  = newerPost |> Option.map (fun p -> p.title)
+          olderLink  = olderLink
+          olderName  = olderPost |> Option.map (fun p -> p.title)
+        }
+    return Hash.FromAnonymousObject {| model = model; categories = CategoryCache.get ctx |}
+}
+
+// GET /page/{pageNbr}
+let pageOfPosts pageNbr : HttpHandler = fun next ctx -> task {
+    let  webLog = WebLogCache.get ctx
+    let  conn   = conn ctx
+    let! posts  = Data.Post.findPageOfPublishedPosts webLog.id pageNbr webLog.postsPerPage conn
+    let! hash   = preparePostList webLog posts PostList "" pageNbr webLog.postsPerPage ctx conn
+    let  title  =
+        match pageNbr, webLog.defaultPage with
+        | 1L, "posts" -> None
+        | _,  "posts" -> Some $"Page {pageNbr}"
+        | _,  _       -> Some $"Page {pageNbr} &laquo; Posts"
+    match title with Some ttl -> hash.Add ("page_title", ttl) | None -> ()
+    if pageNbr = 1L && webLog.defaultPage = "posts" then hash.Add ("is_home", true)
+    return! themedView "index" next ctx hash
+}
+
+// GET /category/{slug}/
+// GET /category/{slug}/page/{pageNbr}
+let pageOfCategorizedPosts : HttpHandler = fun next ctx -> task {
+    let  webLog  = WebLogCache.get ctx
+    let  conn    = conn ctx
+    let  pageNbr, slug = pathAndPageNumber ctx
+    let  allCats = CategoryCache.get ctx
+    let  cat     = allCats |> Array.find (fun cat -> cat.slug = slug)
+    // Category pages include posts in subcategories
+    let  catIds  =
+        allCats
+        |> Seq.ofArray
+        |> Seq.filter (fun c -> c.id = cat.id || Array.contains cat.name c.parentNames)
+        |> Seq.map (fun c -> CategoryId c.id)
+        |> List.ofSeq
+    match! Data.Post.findPageOfCategorizedPosts webLog.id catIds pageNbr webLog.postsPerPage conn with
+    | posts when List.length posts > 0 ->
+        let! hash    = preparePostList webLog posts CategoryList cat.slug pageNbr webLog.postsPerPage ctx conn
+        let  pgTitle = if pageNbr = 1L then "" else $""" <small class="archive-pg-nbr">(Page {pageNbr})</small>"""
+        hash.Add ("page_title", $"{cat.name}: Category Archive{pgTitle}")
+        hash.Add ("subtitle", cat.description.Value)
+        hash.Add ("is_category", true)
+        return! themedView "index" next ctx hash
+    | _ -> return! Error.notFound next ctx
+}
+
+open System.Web
+
+// GET /tag/{tag}/
+// GET /tag/{tag}/page/{pageNbr}
+let pageOfTaggedPosts : HttpHandler = fun next ctx -> task {
+    let  webLog  = WebLogCache.get ctx
+    let  conn    = conn ctx
+    let  pageNbr, rawTag = pathAndPageNumber ctx
+    let  tag     = HttpUtility.UrlDecode rawTag
+    match! Data.Post.findPageOfTaggedPosts webLog.id tag pageNbr webLog.postsPerPage conn with
+    | posts when List.length posts > 0 ->
+        let! hash    = preparePostList webLog posts TagList rawTag pageNbr webLog.postsPerPage ctx conn
+        let  pgTitle = if pageNbr = 1L then "" else $""" <small class="archive-pg-nbr">(Page {pageNbr})</small>"""
+        hash.Add ("page_title", $"Posts Tagged &ldquo;{tag}&rdquo;{pgTitle}")
+        hash.Add ("is_tag", true)
+        return! themedView "index" next ctx hash
+    // Other systems use hyphens for spaces; redirect if this is an old tag link
+    | _ ->
+        let spacedTag = tag.Replace ("-", " ")
+        match! Data.Post.findPageOfTaggedPosts webLog.id spacedTag pageNbr 1 conn with
+        | posts when List.length posts > 0 ->
+            let endUrl = if pageNbr = 1L then "" else $"page/{pageNbr}"
+            return! redirectTo true $"""/tag/{spacedTag.Replace (" ", "+")}/{endUrl}""" next ctx
+        | _ -> return! Error.notFound next ctx
+}
+
+// GET /
+let home : HttpHandler = fun next ctx -> task {
+    let webLog = WebLogCache.get ctx
+    match webLog.defaultPage with
+    | "posts" -> return! pageOfPosts 1 next ctx
+    | pageId ->
+        match! Data.Page.findById (PageId pageId) webLog.id (conn ctx) with
+        | Some page ->
+            return!
+                Hash.FromAnonymousObject {|
+                    page       = DisplayPage.fromPage webLog page
+                    page_title = page.title
+                    is_home    = true
+                |}
+                |> themedView (defaultArg page.template "single-page") next ctx
+        | None -> return! Error.notFound next ctx
+}
+
+open System.IO
+open System.ServiceModel.Syndication
+open System.Text.RegularExpressions
+open System.Xml
+
+// GET /feed.xml
+//   (Routing handled by catch-all handler for future configurability)
+let generateFeed : HttpHandler = fun next ctx -> backgroundTask {
+    let  conn    = conn ctx
+    let  webLog  = WebLogCache.get ctx
+    let  urlBase = $"https://{webLog.urlBase}/"
+    // TODO: hard-coded number of items
+    let! posts   = Data.Post.findPageOfPublishedPosts webLog.id 1L 10 conn
+    let! authors = getAuthors webLog posts conn
+    let  cats    = CategoryCache.get ctx
+    
+    let toItem (post : Post) =
+        let plainText =
+            Regex.Replace (post.text, "<(.|\n)*?>", "")
+            |> function
+            | txt when txt.Length < 255 -> txt
+            | txt -> $"{txt.Substring (0, 252)}..."
+        let item = SyndicationItem (
+            Id              = $"{urlBase}{Permalink.toString post.permalink}",
+            Title           = TextSyndicationContent.CreateHtmlContent post.title,
+            PublishDate     = DateTimeOffset post.publishedOn.Value,
+            LastUpdatedTime = DateTimeOffset post.updatedOn,
+            Content         = TextSyndicationContent.CreatePlaintextContent plainText)
+        item.AddPermalink (Uri item.Id)
+        
+        let encoded = post.text.Replace("src=\"/", $"src=\"{urlBase}").Replace ("href=\"/", $"href=\"{urlBase}")
+        item.ElementExtensions.Add ("encoded", "http://purl.org/rss/1.0/modules/content/", encoded)
+        item.Authors.Add (SyndicationPerson (
+            Name = (authors |> List.find (fun a -> a.name = WebLogUserId.toString post.authorId)).value))
+        [ post.categoryIds
+          |> List.map (fun catId ->
+              let cat = cats |> Array.find (fun c -> c.id = CategoryId.toString catId)
+              SyndicationCategory (cat.name, $"{urlBase}category/{cat.slug}/", cat.name))
+          post.tags
+          |> List.map (fun tag ->
+              let urlTag = tag.Replace (" ", "+")
+              SyndicationCategory (tag, $"{urlBase}tag/{urlTag}/", $"{tag} (tag)"))
+        ]
+        |> List.concat
+        |> List.iter item.Categories.Add
+        item
+        
+    
+    let feed = SyndicationFeed ()
+    feed.Title           <- TextSyndicationContent webLog.name
+    feed.Description     <- TextSyndicationContent <| defaultArg webLog.subtitle webLog.name
+    feed.LastUpdatedTime <- DateTimeOffset <| (List.head posts).updatedOn
+    feed.Generator       <- generator ctx
+    feed.Items           <- posts |> Seq.ofList |> Seq.map toItem
+    feed.Language        <- "en"
+    feed.Id              <- urlBase
+    
+    feed.Links.Add (SyndicationLink (Uri $"{urlBase}feed.xml", "self", "", "application/rss+xml", 0L))
+    feed.AttributeExtensions.Add
+        (XmlQualifiedName ("content", "http://www.w3.org/2000/xmlns/"), "http://purl.org/rss/1.0/modules/content/")
+    feed.ElementExtensions.Add ("link", "", urlBase)
+    
+    use mem = new MemoryStream ()
+    use xml = XmlWriter.Create mem
+    feed.SaveAsRss20 xml
+    xml.Close ()
+    
+    let _ = mem.Seek (0L, SeekOrigin.Begin)
+    let rdr = new StreamReader(mem)
+    let! output = rdr.ReadToEndAsync ()
+    
+    return! ( setHttpHeader "Content-Type" "text/xml" >=> setStatusCode 200 >=> setBodyFromString output) next ctx
+}
+
+/// Sequence where the first returned value is the proper handler for the link
+let private deriveAction ctx : HttpHandler seq =
+    let webLog    = WebLogCache.get ctx
+    let conn      = conn ctx
+    let permalink = (string >> Permalink) ctx.Request.RouteValues["link"]
+    let await it  = (Async.AwaitTask >> Async.RunSynchronously) it
+    seq {
+        // Current post
+        match Data.Post.findByPermalink permalink webLog.id conn |> await with
+        | Some post -> 
+            let model = preparePostList webLog [ post ] SinglePost "" 1 1 ctx conn |> await
+            model.Add ("page_title", post.title)
+            yield fun next ctx -> themedView "single-post" next ctx model
+        | None -> ()
+        // Current page
+        match Data.Page.findByPermalink permalink webLog.id conn |> await with
+        | Some page ->
+            yield fun next ctx ->
+                Hash.FromAnonymousObject {| page = DisplayPage.fromPage webLog page; page_title = page.title |}
+                |> themedView (defaultArg page.template "single-page") next ctx
+        | None -> ()
+        // RSS feed
+        // TODO: configure this via web log
+        if Permalink.toString permalink = "feed.xml" then yield generateFeed
+        // Prior post
+        match Data.Post.findCurrentPermalink permalink webLog.id conn |> await with
+        | Some link -> yield redirectTo true $"/{Permalink.toString link}"
+        | None -> ()
+        // Prior permalink
+        match Data.Page.findCurrentPermalink permalink webLog.id conn |> await with
+        | Some link -> yield redirectTo true $"/{Permalink.toString link}"
+        | None -> ()
+    }
+
+// GET {**link}
+let catchAll : HttpHandler = fun next ctx -> task {
+    match deriveAction ctx |> Seq.tryHead with
+    | Some handler -> return! handler next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+// GET /posts
+// GET /posts/page/{pageNbr}
+let all pageNbr : HttpHandler = requireUser >=> fun next ctx -> task {
+    let  webLog = WebLogCache.get ctx
+    let  conn   = conn ctx
+    let! posts  = Data.Post.findPageOfPosts webLog.id pageNbr 25 conn
+    let! hash   = preparePostList webLog posts AdminList "" pageNbr 25 ctx conn
+    hash.Add ("page_title", "Posts")
+    return! viewForTheme "admin" "post-list" next ctx hash
+}
+
+// GET /post/{id}/edit
+let edit postId : HttpHandler = requireUser >=> fun next ctx -> task {
+    let  webLog = WebLogCache.get ctx
+    let  conn   = conn     ctx
+    let! result = task {
+        match postId with
+        | "new" -> return Some ("Write a New Post", { Post.empty with id = PostId "new" })
+        | _ ->
+            match! Data.Post.findByFullId (PostId postId) webLog.id conn with
+            | Some post -> return Some ("Edit Post", post)
+            | None -> return None
+    }
+    match result with
+    | Some (title, post) ->
+        let! cats = Data.Category.findAllForView webLog.id conn
+        return!
+            Hash.FromAnonymousObject {|
+                csrf       = csrfToken ctx
+                model      = EditPostModel.fromPost webLog post
+                page_title = title
+                categories = cats
+            |}
+            |> viewForTheme "admin" "post-edit" next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+// POST /post/save
+let save : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let! model    = ctx.BindFormAsync<EditPostModel> ()
+    let  webLogId = webLogId ctx
+    let  conn     = conn     ctx
+    let  now      = DateTime.UtcNow
+    let! pst      = task {
+        match model.postId with
+        | "new" ->
+            return Some
+                { Post.empty with
+                    id        = PostId.create ()
+                    webLogId  = webLogId
+                    authorId  = userId ctx
+                }
+        | postId -> return! Data.Post.findByFullId (PostId postId) webLogId conn
+    }
+    match pst with
+    | Some post ->
+        let revision = { asOf = now; text = MarkupText.parse $"{model.source}: {model.text}" }
+        // Detect a permalink change, and add the prior one to the prior list
+        let post =
+            match Permalink.toString post.permalink with
+            | "" -> post
+            | link when link = model.permalink -> post
+            | _ -> { post with priorPermalinks = post.permalink :: post.priorPermalinks }
+        let post =
+            { post with
+                title       = model.title
+                permalink   = Permalink model.permalink
+                publishedOn = if model.doPublish then Some now else post.publishedOn
+                updatedOn   = now
+                text        = MarkupText.toHtml revision.text
+                tags        = model.tags.Split ","
+                              |> Seq.ofArray
+                              |> Seq.map (fun it -> it.Trim().ToLower ())
+                              |> Seq.sort
+                              |> List.ofSeq
+                categoryIds = model.categoryIds |> Array.map CategoryId |> List.ofArray
+                status      = if model.doPublish then Published else post.status
+                metadata    = Seq.zip model.metaNames model.metaValues
+                              |> Seq.filter (fun it -> fst it > "")
+                              |> Seq.map (fun it -> { name = fst it; value = snd it })
+                              |> Seq.sortBy (fun it -> $"{it.name.ToLower ()} {it.value.ToLower ()}")
+                              |> List.ofSeq
+                revisions   = match post.revisions |> List.tryHead with
+                              | Some r when r.text = revision.text -> post.revisions
+                              | _ -> revision :: post.revisions
+            }
+        let post =
+            match model.setPublished with
+            | true ->
+                let dt = DateTime (model.pubOverride.Value.ToUniversalTime().Ticks, DateTimeKind.Utc)
+                printf $"**** DateKind = {dt.Kind}"
+                match model.setUpdated with
+                | true ->
+                    { post with
+                        publishedOn = Some dt
+                        updatedOn   = dt
+                        revisions   = [ { (List.head post.revisions) with asOf = dt } ]
+                    }
+                | false -> { post with publishedOn = Some dt }
+            | false -> post
+        do! (match model.postId with "new" -> Data.Post.add | _ -> Data.Post.update) post conn
+        // If the post was published or its categories changed, refresh the category cache
+        if model.doPublish
+           || not (pst.Value.categoryIds
+                   |> List.append post.categoryIds
+                   |> List.distinct
+                   |> List.length = List.length pst.Value.categoryIds) then
+            do! CategoryCache.update ctx
+        do! addMessage ctx { UserMessage.success with message = "Post saved successfully" }
+        return! redirectToGet $"/post/{PostId.toString post.id}/edit" next ctx
+    | None -> return! Error.notFound next ctx
+}

src/MyWebLog/Handlers/Routes.fs

@@ -0,0 +1,70 @@
+/// Routes for this application
+module MyWebLog.Handlers.Routes
+
+open Giraffe.EndpointRouting
+
+/// The endpoints defined in the above handlers
+let endpoints = [
+    GET [
+        route "/" Post.home
+    ]
+    subRoute "/admin" [
+        GET [
+            route ""          Admin.dashboard
+            route "/settings" Admin.settings
+        ]
+        POST [
+            route "/settings" Admin.saveSettings
+        ]
+    ]
+    subRoute "/categor" [
+        GET [
+            route  "ies"        Category.all
+            routef "y/%s/edit"  Category.edit
+            route  "y/{**slug}" Post.pageOfCategorizedPosts
+        ]
+        POST [
+            route  "y/save"      Category.save
+            routef "y/%s/delete" Category.delete
+        ]
+    ]
+    subRoute "/page" [
+        GET [
+            routef "/%d"       Post.pageOfPosts
+            //routef "/%d/"      (fun pg -> redirectTo true $"/page/{pg}")
+            routef "/%s/edit"  Page.edit
+            route  "s"         (Page.all 1)
+            routef "s/page/%d" Page.all
+        ]
+        POST [
+            route "/save" Page.save
+        ]
+    ]
+    subRoute "/post" [
+        GET [
+            routef "/%s/edit"  Post.edit
+            route  "s"         (Post.all 1)
+            routef "s/page/%d" Post.all
+        ]
+        POST [
+            route "/save" Post.save
+        ]
+    ]
+    subRoute "/tag" [
+        GET [
+            route "/{**slug}" Post.pageOfTaggedPosts
+        ]
+    ]
+    subRoute "/user" [
+        GET [
+            route "/edit"    User.edit
+            route "/log-on"  (User.logOn None)
+            route "/log-off" User.logOff
+        ]
+        POST [
+            route "/log-on" User.doLogOn
+            route "/save"   User.save
+        ]
+    ]
+    route "{**link}" Post.catchAll
+]

src/MyWebLog/Handlers/User.fs

@@ -0,0 +1,117 @@
+/// Handlers to manipulate users
+module MyWebLog.Handlers.User
+
+open System
+open System.Security.Cryptography
+open System.Text
+
+/// Hash a password for a given user
+let hashedPassword (plainText : string) (email : string) (salt : Guid) =
+    let allSalt = Array.concat [ salt.ToByteArray (); Encoding.UTF8.GetBytes email ] 
+    use alg     = new Rfc2898DeriveBytes (plainText, allSalt, 2_048)
+    Convert.ToBase64String (alg.GetBytes 64)
+
+open DotLiquid
+open Giraffe
+open MyWebLog.ViewModels
+
+// GET /user/log-on
+let logOn returnUrl : HttpHandler = fun next ctx -> task {
+    let returnTo =
+        match returnUrl with
+        | Some _ -> returnUrl
+        | None ->
+            match ctx.Request.Query.ContainsKey "returnUrl" with
+            | true -> Some ctx.Request.Query["returnUrl"].[0]
+            | false -> None
+    return!
+        Hash.FromAnonymousObject {|
+            model      = { LogOnModel.empty with returnTo = returnTo }
+            page_title = "Log On"
+            csrf       = csrfToken ctx
+        |}
+        |> viewForTheme "admin" "log-on" next ctx
+}
+
+open System.Security.Claims
+open Microsoft.AspNetCore.Authentication
+open Microsoft.AspNetCore.Authentication.Cookies
+open MyWebLog
+
+// POST /user/log-on
+let doLogOn : HttpHandler = validateCsrf >=> fun next ctx -> task {
+    let! model  = ctx.BindFormAsync<LogOnModel> ()
+    let  webLog = WebLogCache.get ctx
+    match! Data.WebLogUser.findByEmail model.emailAddress webLog.id (conn ctx) with 
+    | Some user when user.passwordHash = hashedPassword model.password user.userName user.salt ->
+        let claims = seq {
+            Claim (ClaimTypes.NameIdentifier, WebLogUserId.toString user.id)
+            Claim (ClaimTypes.Name,           $"{user.firstName} {user.lastName}")
+            Claim (ClaimTypes.GivenName,      user.preferredName)
+            Claim (ClaimTypes.Role,           user.authorizationLevel.ToString ())
+        }
+        let identity = ClaimsIdentity (claims, CookieAuthenticationDefaults.AuthenticationScheme)
+
+        do! ctx.SignInAsync (identity.AuthenticationType, ClaimsPrincipal identity,
+            AuthenticationProperties (IssuedUtc = DateTimeOffset.UtcNow))
+        do! addMessage ctx
+                { UserMessage.success with message = $"Logged on successfully | Welcome to {webLog.name}!" }
+        return! redirectToGet (match model.returnTo with Some url -> url | None -> "/admin") next ctx
+    | _ ->
+        do! addMessage ctx { UserMessage.error with message = "Log on attempt unsuccessful" }
+        return! logOn model.returnTo next ctx
+}
+
+// GET /user/log-off
+let logOff : HttpHandler = fun next ctx -> task {
+    do! ctx.SignOutAsync CookieAuthenticationDefaults.AuthenticationScheme
+    do! addMessage ctx { UserMessage.info with message = "Log off successful" }
+    return! redirectToGet "/" next ctx
+}
+
+/// Display the user edit page, with information possibly filled in
+let private showEdit (hash : Hash) : HttpHandler = fun next ctx -> task {
+    hash.Add ("page_title", "Edit Your Information")
+    hash.Add ("csrf", csrfToken ctx)
+    return! viewForTheme "admin" "user-edit" next ctx hash
+}
+
+// GET /user/edit
+let edit : HttpHandler = requireUser >=> fun next ctx -> task {
+    match! Data.WebLogUser.findById (userId ctx) (conn ctx) with
+    | Some user -> return! showEdit (Hash.FromAnonymousObject {| model = EditUserModel.fromUser user |}) next ctx
+    | None -> return! Error.notFound next ctx
+}
+
+// POST /user/save
+let save : HttpHandler = requireUser >=> validateCsrf >=> fun next ctx -> task {
+    let! model = ctx.BindFormAsync<EditUserModel> ()
+    if model.newPassword = model.newPasswordConfirm then
+        let conn = conn ctx
+        match! Data.WebLogUser.findById (userId ctx) conn with
+        | Some user ->
+            let pw, salt =
+                if model.newPassword = "" then
+                    user.passwordHash, user.salt
+                else
+                    let newSalt = Guid.NewGuid ()
+                    hashedPassword model.newPassword user.userName newSalt, newSalt
+            let user =
+                { user with
+                    firstName     = model.firstName
+                    lastName      = model.lastName
+                    preferredName = model.preferredName
+                    passwordHash  = pw
+                    salt          = salt
+                }
+            do! Data.WebLogUser.update user conn
+            let pwMsg = if model.newPassword = "" then "" else " and updated your password"
+            do! addMessage ctx { UserMessage.success with message = $"Saved your information{pwMsg} successfully" }
+            return! redirectToGet "/user/edit" next ctx
+        | None -> return! Error.notFound next ctx
+    else
+        do! addMessage ctx { UserMessage.error with message = "Passwords did not match; no updates made" }
+        return! showEdit (Hash.FromAnonymousObject {|
+                model = { model with newPassword = ""; newPasswordConfirm = "" }
+            |}) next ctx
+}

src/MyWebLog/MyWebLog.fsproj

@@ -9,15 +9,22 @@
   <ItemGroup>
     <Content Include="appsettings.json" CopyToOutputDirectory="Always" />
     <Compile Include="Caches.fs" />
-    <Compile Include="Handlers.fs" />
+    <Compile Include="Handlers\Error.fs" />
+    <Compile Include="Handlers\Helpers.fs" />
+    <Compile Include="Handlers\Admin.fs" />
+    <Compile Include="Handlers\Category.fs" />
+    <Compile Include="Handlers\Page.fs" />
+    <Compile Include="Handlers\Post.fs" />
+    <Compile Include="Handlers\User.fs" />
+    <Compile Include="Handlers\Routes.fs" />
     <Compile Include="Program.fs" />
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="DotLiquid" Version="2.2.614" />
+    <PackageReference Include="DotLiquid" Version="2.2.656" />
     <PackageReference Include="Giraffe" Version="6.0.0" />
     <PackageReference Include="RethinkDB.DistributedCache" Version="0.9.0-alpha05" />
-    <PackageReference Update="FSharp.Core" Version="6.0.3" />
+    <PackageReference Update="FSharp.Core" Version="6.0.4" />
     <PackageReference Include="System.ServiceModel.Syndication" Version="6.0.0" />
   </ItemGroup>
 
@@ -31,6 +38,4 @@
     <None Include=".\wwwroot\**" CopyToOutputDirectory="Always" />
   </ItemGroup>
 
-  <ItemGroup />
-
 </Project>

src/MyWebLog/Program.fs

@@ -276,7 +276,7 @@ let main args =
         let _ = app.UseStaticFiles ()
         let _ = app.UseRouting ()
         let _ = app.UseSession ()
-        let _ = app.UseGiraffe Handlers.endpoints
+        let _ = app.UseGiraffe Handlers.Routes.endpoints
 
         app.Run()
 

src/MyWebLog/appsettings.json

@@ -3,5 +3,5 @@
     "hostname": "data02.bitbadger.solutions",
     "database": "myWebLog_dev"
   },
-  "Generator": "myWebLog 2.0-alpha02"
+  "Generator": "myWebLog 2.0-alpha03"
 }