A minimal filesystem-based publishing engine with Markdown support and code highlighting
NimblePublisheris a minimal filesystem-based publishing engine with Markdown support and code highlighting.
use NimblePublisher, build: Article, from: "articles/**/*.md", as: :articles, highlighters: [:makeup_elixir, :makeup_erlang]
The example above will get all articles in the given directory, call
Article.build/3for each article, passing the filename, the metadata, and the article body, and define a module attribute named
@articleswith all built articles returned by the
Article.build/3function.
Each article in the articles directory must have the format:
%{ title: "Hello world" } --- Body of the "Hello world" article.This is a markdown document with support for code highlighters:
IO.puts "hello world".
:build- the name of the module that will build each entry
:from- a wildcard pattern where to find all entries
:as- the name of the module attribute to store all built entries
:highlighters- which code highlighters to use.
NimblePublisheruses
Makeupfor syntax highlighting and you will need to add its
.cssclasses. You can generate the CSS classes by calling
Makeup.stylesheet(:vim_style, "makeup")inside
iex -S mix. You can replace
:vim_styleby any style of your choice defined here.
Let's see a complete example. First add
nimble_publisherwith the desired highlighters as a dependency:
def deps do [ {:nimble_publisher, "~> 0.1.0"}, {:makeup_elixir, ">= 0.0.0"}, {:makeup_erlang, ">= 0.0.0"} ] end
In this example, we are building a blog. Each post stays in the "posts" directory with the format:
/posts/YEAR/MONTH-DAY-ID.md
A typical blog post will look like this:
# /posts/2020/04-17-hello-world.md %{ title: "Hello world!", author: "José Valim", tags: ~w(hello), description: "Let's learn how to say hello world" } --- This is the post.
Therefore, we will define a Post struct that expects all of the fields above. We will also have a
:datefield that we will build from the filename. Overall, it will look like this:
defmodule MyApp.Blog.Post do @enforce_keys [:id, :author, :title, :body, :description, :tags, :date] defstruct [:id, :author, :title, :body, :description, :tags, :date]def build(filename, attrs, body) do [year, month_day_id] = filename |> Path.rootname() |> Path.split() |> Enum.take(-2) [month, day, id] = String.split(month_day_id, "-", parts: 3) date = Date.from_iso8601!("#{year}-#{month}-#{day}") struct!(MODULE, [id: id, date: date, body: body] ++ Map.to_list(attrs)) end end
Now, we are ready to define our
MyApp.Blogwith
NimblePublisher:
defmodule MyApp.Blog do use NimblePublisher, build: Post, from: "posts/**/*.md", as: :posts, highlighters: [:makeup_elixir, :makeup_erlang]The @posts variable is first defined by NimblePublisher.
Let's further modify it by sorting all posts by descending date.
@posts Enum.sort_by(@posts, & &1.date, {:desc, Date})
Let's also get all tags
@tags @posts |> Enum.flat_map(& &1.tags) |> Enum.uniq() |> Enum.sort()
And finally export them
def all_posts, do: @posts def all_tags, do: @tags end
Important: Avoid injecting the
@postsattribute into multiple functions, as each call will make a complete copy of all posts. For example, if you want to show define
recent_posts()as well as
all_posts(), DO NOT do this:
def all_posts, do: @posts def recent_posts, do: Enum.take(@posts, 3)
Instead do this:
def all_posts, do: @posts def recent_posts, do: Enum.take(all_posts(), 3)
You may want to define other helpers to traverse your published resources. For example, if you want to get posts by ID or with a given tag, you can define additional functions as shown below:
defmodule NotFoundError do defexception [:message, plug_status: 404] enddef get_post_by_id!(id) do Enum.find(all_posts(), &(&1.id == id)) || raise NotFoundError, "post with id=#{id} not found" end
def get_posts_by_tag!(tag) do case Enum.filter(all_posts(), &(tag in &1.tags)) do [] -> raise NotFoundError, "posts with tag=#{tag} not found" posts -> posts end end
If you are using Phoenix, you can enable live reloading by simply telling Phoenix to watch the “posts” directory. Open up "config/dev.exs", search for
live_reload:and add this to the list of patterns:
live_reload: [ patterns: [ ..., ~r"posts/*/.*(md)$" ] ]
All nimble libraries by Dashbit:
Copyright 2020 Dashbit
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.