Customize the menu items of {{fsdocs-list-of-documents}} and {{fsdocs-list-of-namespaces}}

[nojaf]

Hello, we are currently experimenting with FsDoc. We aim to have our own template and are experimenting with Bootstrap 5, Sass and some other ideas.

We are currently hitting a limitation that:

{{fsdocs-list-of-documents}}
{{fsdocs-list-of-namespaces}}

is generating some HTML that doesn't fit our needs. Would there be a way to have some control over what this outputs?

//cc @yisusalanpng

[dsyme]

Certainly, you can suggest something?

[nojaf]

Well, I can think of two suggestions.

The first would be introducing another replacement variable that outputs JSON instead of HTML. {{fsdocs-list-of-documents-json}}. Having that opens the door to easily constructing HTML on the client.

The second would be to add an option to pass something that can transform https://github.com/nojaf/FSharp.Formatting/blob/82e0c8a09136fa56dcbcd931c290fcce97462970/src/fsdocs-tool/BuildCommand.fs#L553-L586. Maybe an F# script? Or provide an API endpoint, where some data will be posted and the response body is used as the replacement value. I'm not quite sure what could be elegant.

[nojaf]

@dsyme, I made an experiment with transforming the menu information in an outside endpoint. https://github.com/fsprojects/FSharp.Formatting/commit/a4d9f8f3fa3acbdb2337a57e35ebab4b48cccbac

I made a small script to act as the receiving endpoint:

#r "nuget: Suave"
#r "nuget: Thoth.Json.Net, 8.0.0"
#r "nuget: Fable.React, 8.0.1"

open System.Net
open Suave
open Suave.Filters
open Suave.Operators
open Suave.Successful
open Thoth.Json.Net

type Item = {
    Title: string
    Category: string
    CategoryIndex: int
    Index: int
    Link: string
}

let decodeStringAsInt = Decode.string |> Decode.map (int)

let decodeItem: Decoder<Item> =
    Decode.object (fun get -> {
        Category = get.Required.Field "category" Decode.string
        CategoryIndex = get.Required.Field "categoryIndex" decodeStringAsInt
        Index = get.Required.Field "index" decodeStringAsInt
        Link = get.Required.Field "link" Decode.string
        Title = get.Required.Field "title" Decode.string
    }
    )

open Fable.React
open Fable.React.Props

let view (items: Item array) : string =
    let groups = Array.groupBy (fun i -> i.CategoryIndex) items

    let children =
        groups
        |> Array.map (fun (_, groupItems) ->
            let groupTitle = groupItems[0].Category

            let id = $"menu-{groupTitle}-collapse".Replace(" ", "-").Trim().ToLower()

            let groupItems =
                groupItems
                |> Array.map (fun (gi: Item) ->
                    li [] [ a [ Href gi.Link; ClassName "ms-4 my-2 d-block" ] [ str gi.Title ] ]
                )

            li [ ClassName "mb-1" ] [
                button [
                    ClassName "btn align-items-center rounded"
                    Data("bs-toggle", "collapse")
                    Data("bs-target", $"#{id}")
                    AriaExpanded true
                ] [ str groupTitle ]
                div [ ClassName "collapse show"; Id id ] [
                    ul [ ClassName "list-unstyled fw-normal pb-1 small" ] groupItems
                ]
            ]
        )

    let element = fragment [] children
    Fable.ReactServer.renderToString (element)

let menuPart =
    POST
    >=> Filters.path "/menu"
    >=> (fun (ctx: HttpContext) -> async {
        let json = System.Text.Encoding.UTF8.GetString(ctx.request.rawForm)
        printfn "received: %s" json

        match Decode.fromString (Decode.array decodeItem) json with
        | Error err -> return! OK $"<div>Failed to decode, {err}</div>" ctx
        | Ok items ->
            let html = view items
            printfn "html:\n%s" html
            return! OK html ctx
    }
    )

let port = 8906us

startWebServer
    { defaultConfig with
        bindings = [ HttpBinding.create HTTP IPAddress.Loopback port ]
    }
    menuPart

This is quite the escape hatch, but we can do whatever we want inside our endpoint. And I think the impact for FsDocs is minimal. If anything fails, you are on your own, which should be the policy for such a malpractise.

[dsyme]

Adding json substitution seems dead simple. Please go ahead with that?

[nojaf]

After giving this some more thought and discussing it with a friend, I like to propose an alternative. What if we work with a _menu_template.html and _menu-item_template.html.

Where the default of _menu_template.html would be:

<li class="nav-header">
  {{fsdocs-menu-header-content}}
</li>
{{fsdocs-menu-items}}

and _menu-item_template.html

<li class="nav-item"><a href="{{fsdocs-menu-item-link}}" class="nav-link">{{fsdocs-menu-item-content}}</a></li>

If the additional template files are present, we would transform

https://github.com/fsprojects/FSharp.Formatting/blob/82e0c8a09136fa56dcbcd931c290fcce97462970/src/fsdocs-tool/BuildCommand.fs#L553-L586

accordingly. If not, just return the default behaviour.

[dsyme]

Seems reasonable!

[nojaf]

Thanks, we will prepare a concrete proposal in a PR!