feat: initial release

.github/workflows/test.yml

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+name: 💜 Test
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: "26.0.2"
+          gleam-version: "1.2.1"
+          rebar3-version: "3"
+          # elixir-version: "1.15.4"
+      - run: gleam deps download
+      - run: gleam test
+      - run: gleam format --check src test

.gitignore

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+# Gleam
+*.beam
+*.ez
+/build
+erl_crash.dump
+
+# Visual Studio Code
+.vscode

Earthfile

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+VERSION 0.8
+
+all:
+  BUILD +docker
+
+docker:
+  ARG tag=latest
+
+  FROM ghcr.io/gleam-lang/gleam:v1.2.1-erlang-alpine
+
+  COPY +build/erlang-shipment/ /momoka/erlang-shipment/
+
+  WORKDIR /momoka/
+
+  ENTRYPOINT ["./erlang-shipment/entrypoint.sh"]
+
+  CMD ["run"]
+
+  SAVE IMAGE --push fuwn/momoka:${tag}
+
+deps:
+  FROM ghcr.io/gleam-lang/gleam:v1.2.0-erlang-alpine
+
+  RUN apk add --no-cache build-base
+
+build:
+  FROM +deps
+
+  WORKDIR /momoka/
+
+  COPY src/ /momoka/src/
+  COPY gleam.toml /momoka/
+  COPY manifest.toml /momoka/
+
+  RUN gleam build \
+    && cd build/ \
+    && gleam export erlang-shipment
+
+  SAVE ARTIFACT /momoka/build/erlang-shipment/

README.md

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+# 🏕️ Momoka
+
+> A Gemini-to-Gopher Proxy
+
+Momoka is a Gopher proxy that sits in between Gopher clients and Gemini servers.
+It translates any Gemini requests containing Gemtext into Gopher-compatible
+responses.
+
+Momoka is written in under 300 (280) lines of code and written in the functional
+[Gleam](https://gleam.run). It's designed to be small and simple.
+
+## Usage
+
+If you'd like to test out a production deployment of Momoka, you can visit
+[`gopher://fuwn.me:70/1`](gopher://fuwn.me:70/1).
+
+### Local
+
+```bash
+$ git clone git@github.com:Fuwn/momoka.git
+$ cd momoka
+$ gleam run
+$ # or
+$ nix run
+```
+
+### Docker
+
+```shell
+docker run -p '70:70' --rm fuwn/momoka:latest
+```
+
+### Proxy
+
+By default, top-level requests, like `gopher://fuwn.me/1`, are proxied to
+their mapped Gemini equivalents. Here are a few examples.
+
+- [`gopher://fuwn.me`](gopher://fuwn.me) =>
+  [`gemini://fuwn.me`](gemini://fuwn.me)
+- [`gopher://fuwn.me/1`](gopher://fuwn.me/1) =>
+  [`gemini://fuwn.me`](gemini://fuwn.me)
+- [`gopher://fuwn.me/1/index2`](gopher://fuwn.me/1/index2) =>
+  [`gemini://fuwn.me/index2`](gemini://fuwn.me/index2)
+
+Prepending `/proxy/` to the path will allow you to proxy any Gemini server.
+Here are a few examples.
+
+- [`gopher://fuwn.me/1/proxy/geminiprotocol.net`](gopher://fuwn.me/1/proxy/geminiprotocol.net)
+  => [`gemini://geminiprotocol.net`](gemini://geminiprotocol.net)
+- [`gopher://fuwn.me/1/proxy/fuwn.me/index2`](gopher://fuwn.me/1/proxy/fuwn.me/index2)
+  => [`gemini://fuwn.me/index2`](`gemini://fuwn.me/index2`)
+
+### Configuration
+
+Momoka contains three environment variables that can be set to your liking.
+
+- `ROOT` – The root Gemini capsule to proxy for top-level requests (defaults to
+  `fuwn.me`)
+- `PORT` – The port to listen on for Gopher clients (defaults to `70`)
+- `GEMINI_PROXY` – A raw-Gemtext producing Gemini-to-HTTP proxy. (defaults to
+  the [fuwn.me](https://fuwn.me)
+  [September](https://github.com/gemrest/september) instance)
+
+## GemRest
+
+I'm also the author of [GemRest](https://github.com/gemrest), the largest
+organisation of Gemini-oriented software, tooling, and libraries. If you're
+interested in Gemini, I'd recommend checking it out.
+
+## Licence
+
+This project is licensed with the [GNU General Public License v3.0](./LICENSE).

flake.nix

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+{
+  description = "Gemini-to-Gopher Proxy";
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+    nix-gleam.url = "github:arnarg/nix-gleam";
+    gitignore = {
+      url = "github:hercules-ci/gitignore.nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+  outputs = { self, nixpkgs, flake-utils, nix-gleam, gitignore, ... }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs {
+          inherit system;
+          overlays = [
+            nix-gleam.overlays.default
+          ];
+        };
+        inherit (gitignore.lib) gitignoreSource;
+      in
+      {
+        packages.default = pkgs.buildGleamApplication {
+          src = gitignoreSource ./.;
+          rebar3Package = pkgs.rebar3WithPlugins {
+            plugins = with pkgs.beamPackages; [ pc ];
+          };
+        };
+        devShell = pkgs.mkShell {
+          buildInputs = [ pkgs.gleam pkgs.rebar3 ];
+        };
+      }
+    );
+}

gleam.toml

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+# For a full reference of all the available options, you can have a look at
+# https://gleam.run/writing-gleam/gleam-toml/.
+
+name = "momoka"
+version = "1.0.0"
+gleam = ">= 0.2.1"
+description = "Gemini-to-Gopher Proxy"
+licenses = ["GPL-3.0-only"]
+repository = { type = "github", user = "Fuwn", repo = "momoka" }
+
+[dependencies]
+gleam_stdlib = ">= 0.34.0 and < 2.0.0"
+glisten = ">= 3.0.0 and < 4.0.0"
+gleam_erlang = ">= 0.25.0 and < 1.0.0"
+gleam_otp = ">= 0.10.0 and < 1.0.0"
+gleam_httpc = ">= 2.2.0 and < 3.0.0"
+gleam_http = ">= 3.6.0 and < 4.0.0"
+envoy = ">= 1.0.1 and < 2.0.0"
+
+[dev-dependencies]
+gleeunit = ">= 1.0.0 and < 2.0.0"

manifest.toml

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+# This file was generated by Gleam
+# You typically do not need to edit this file
+
+packages = [
+  { name = "envoy", version = "1.0.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "envoy", source = "hex", outer_checksum = "CFAACCCFC47654F7E8B75E614746ED924C65BD08B1DE21101548AC314A8B6A41" },
+  { name = "gleam_erlang", version = "0.25.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "054D571A7092D2A9727B3E5D183B7507DAB0DA41556EC9133606F09C15497373" },
+  { name = "gleam_http", version = "3.6.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_http", source = "hex", outer_checksum = "8C07DF9DF8CC7F054C650839A51C30A7D3C26482AC241C899C1CEA86B22DBE51" },
+  { name = "gleam_httpc", version = "2.2.0", build_tools = ["gleam"], requirements = ["gleam_http", "gleam_stdlib"], otp_app = "gleam_httpc", source = "hex", outer_checksum = "CF76C71002DEECF6DC5D9CA83D962728FAE166B57926BE442D827004D3C7DF1B" },
+  { name = "gleam_otp", version = "0.10.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "0B04FE915ACECE539B317F9652CAADBBC0F000184D586AAAF2D94C100945D72B" },
+  { name = "gleam_stdlib", version = "0.38.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "663CF11861179AF415A625307447775C09404E752FF99A24E2057C835319F1BE" },
+  { name = "gleeunit", version = "1.1.2", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "72CDC3D3F719478F26C4E2C5FED3E657AC81EC14A47D2D2DEBB8693CA3220C3B" },
+  { name = "glisten", version = "3.0.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_otp", "gleam_stdlib", "logging", "telemetry"], otp_app = "glisten", source = "hex", outer_checksum = "AEB79A7244CB553A52974EDB87E652607E82749E4EC84B47B1F1BC926F1673C8" },
+  { name = "logging", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "logging", source = "hex", outer_checksum = "A996064F04EF6E67F0668FD0ACFB309830B05D0EE3A0C11BBBD2D4464334F792" },
+  { name = "telemetry", version = "1.2.1", build_tools = ["rebar3"], requirements = [], otp_app = "telemetry", source = "hex", outer_checksum = "DAD9CE9D8EFFC621708F99EAC538EF1CBE05D6A874DD741DE2E689C47FEAFED5" },
+]
+
+[requirements]
+envoy = { version = ">= 1.0.1 and < 2.0.0"}
+gleam_erlang = { version = ">= 0.25.0 and < 1.0.0" }
+gleam_http = { version = ">= 3.6.0 and < 4.0.0" }
+gleam_httpc = { version = ">= 2.2.0 and < 3.0.0" }
+gleam_otp = { version = ">= 0.10.0 and < 1.0.0" }
+gleam_stdlib = { version = ">= 0.34.0 and < 2.0.0" }
+gleeunit = { version = ">= 1.0.0 and < 2.0.0" }
+glisten = { version = ">= 3.0.0 and < 4.0.0" }

src/gemini.gleam

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+import envoy
+import gemtext/parse
+import gleam/bit_array
+import gleam/bytes_builder
+import gleam/http/request
+import gleam/httpc
+import gleam/string
+import gopher
+
+pub fn get_gemtext_from_capsule(message) {
+  let root_capsule = case envoy.get("ROOT") {
+    Ok(capsule) -> capsule
+    _ -> "fuwn.me"
+  }
+  // Gleam isn't mature enough to even have an SSL/TLS libraries that I could
+  // find, and Erlang FFI is unclear, so Momoka uses the
+  // [September](https://github.com/gemrest/september) proxy deployed at
+  // <https://fuwn.me> to fetch the raw Gemini content.
+  //
+  // I'm sure as the language grows, this will be replaced with a more direct
+  // approach.
+  let gemini_proxy = case envoy.get("GEMINI_PROXY") {
+    Ok(proxy) -> proxy
+    _ -> "https://fuwn.me/raw/"
+  }
+  let assert Ok(request) = case bit_array.to_string(message) {
+    Ok(path) -> {
+      case path {
+        "/\r\n" | "\r\n" -> request.to(gemini_proxy <> root_capsule)
+        "/proxy/" <> route ->
+          request.to(gemini_proxy <> string.replace(route, "\r\n", ""))
+        "/" <> path ->
+          request.to(
+            gemini_proxy
+            <> root_capsule
+            <> "/"
+            <> string.replace(path, "\r\n", ""),
+          )
+        _ -> request.to(root_capsule <> string.replace(path, "\r\n", ""))
+      }
+    }
+    _ -> request.to(root_capsule)
+  }
+  let assert Ok(response) = httpc.send(request)
+
+  bytes_builder.from_string(
+    gopher.gemtext_to_gopher(parse.parse_gemtext_raw(response.body)) <> "\r\n",
+  )
+}

src/gemtext/blockquote.gleam

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+import gemtext/gemtext.{type Gemtext}
+import gleam/list
+import gleam/string
+
+pub fn combine_adjacent_blockquote_lines(lines: List(Gemtext)) -> List(Gemtext) {
+  case lines {
+    [gemtext.BlockquoteLine(a), gemtext.BlockquoteLine(b), ..rest] ->
+      combine_adjacent_blockquote_lines([
+        gemtext.Blockquote(string.join([a, b], "\n")),
+        ..rest
+      ])
+    [gemtext.Blockquote(a), gemtext.BlockquoteLine(b), ..rest] ->
+      combine_adjacent_blockquote_lines([
+        gemtext.Blockquote(string.join([a, b], "\n")),
+        ..rest
+      ])
+    [g, ..rest] -> list.append([g], combine_adjacent_blockquote_lines(rest))
+    [] -> []
+  }
+}

src/gemtext/gemtext.gleam

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+import gleam/option.{type Option}
+
+pub type Gemtext {
+  Text(String)
+  Link(to: String, Option(String))
+  Heading(String, depth: Int)
+  ListLine(String)
+  List(List(List(String)))
+  BlockquoteLine(String)
+  Blockquote(String)
+  Preformatted(description: Option(String), body: String)
+  PreformattedLine(String)
+  Whitespace
+}

src/gemtext/heading.gleam

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+import gleam/string
+
+pub fn count_leading_hashes(line: String) -> Int {
+  do_count_leading_hashes(string.to_graphemes(line), 0)
+}
+
+fn do_count_leading_hashes(characters: List(String), accumulator: Int) -> Int {
+  case characters {
+    [c, ..rest] -> {
+      case c {
+        "#" -> do_count_leading_hashes(rest, accumulator + 1)
+        _ -> accumulator
+      }
+    }
+    _ -> accumulator
+  }
+}

src/gemtext/list.gleam

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+import gemtext/gemtext.{type Gemtext}
+import gleam/list
+
+pub fn group_adjacent_list_items(lines: List(Gemtext)) -> List(Gemtext) {
+  case lines {
+    [gemtext.ListLine(a), gemtext.ListLine(b), ..rest] ->
+      group_adjacent_list_items([gemtext.List([[a], [b]]), ..rest])
+    [gemtext.List(lists), gemtext.ListLine(item), ..rest] ->
+      group_adjacent_list_items([
+        gemtext.List(list.append(lists, [[item]])),
+        ..rest
+      ])
+    [g, ..rest] -> list.append([g], group_adjacent_list_items(rest))
+    [] -> []
+  }
+}

src/gemtext/parse.gleam

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+import gemtext/blockquote
+import gemtext/gemtext.{type Gemtext}
+import gemtext/heading
+import gemtext/list as gemtext_list
+import gemtext/preformatted_block
+import gleam/list
+import gleam/option.{None, Some}
+import gleam/string
+
+pub fn parse_gemtext_line(line) -> Gemtext {
+  let trimmed_line = string.trim(line)
+
+  case string.split(trimmed_line, " ") {
+    ["=>", to] -> gemtext.Link(to, None)
+    ["=>", to, ..title] -> gemtext.Link(to, Some(string.join(title, " ")))
+    [">", ..rest] ->
+      gemtext.BlockquoteLine(string.trim_left(string.join(rest, " ")))
+    ["*", ..rest] -> gemtext.ListLine(string.trim_left(string.join(rest, " ")))
+    [""] -> gemtext.Whitespace
+    _ -> {
+      case string.to_graphemes(trimmed_line) {
+        ["#", ..rest] ->
+          gemtext.Heading(
+            string.trim_left(string.replace(string.join(rest, ""), "#", "")),
+            heading.count_leading_hashes(line),
+          )
+        ["`", "`", "`", ..rest] ->
+          gemtext.PreformattedLine(string.trim_left(
+            "```\n" <> string.join(rest, ""),
+          ))
+        _ -> gemtext.Text(line)
+      }
+    }
+  }
+}
+
+pub fn parse_gemtext(text: String) -> List(Gemtext) {
+  string.split(text, "\n")
+  |> preformatted_block.group_adjacent_preformatted_block_lines
+  |> list.map(parse_gemtext_line)
+  |> gemtext_list.group_adjacent_list_items
+  |> blockquote.combine_adjacent_blockquote_lines
+}
+
+pub fn parse_gemtext_raw(text: String) -> List(Gemtext) {
+  string.split(text, "\n")
+  |> preformatted_block.group_adjacent_preformatted_block_lines
+  |> list.map(parse_gemtext_line)
+}