Feat/dynamic import (#473)

* Make the channel importer versions dynamic

* few things fromt he list

1. add nixos-org-configurations as input to flake.nix
2. evaluate channels.nix file and export channels via environment variable.
   that environment variable (lets call it NIXOS_CHANNELS) should be present
   during the build and inside the nix shell. the content of the variable can
   be JSON.
3. we pickup the NIXOS_CHANNELS environment variable in
   frontend/webpack.config.js and pass it further to webpack process, just
   like we do with ELASTICSEARCH_MAPPING_SCHEMA_VERSION.
4. we forward NIXOS_CHANNELS to Elm via frontend/src/index.js as an Elm
   application flag. Just like we do with other variables there.

* Decode nixosChannels in Elm

* Use nixosChannels that came via application flag

* read nixos channels in github action

* defaultNixOSChannel should be calculated

* add two pointers where the check should be added

* pass nixosChannels to flake-info and remove title, rather calculate it

* Add NixosChannels struct validation and validation Error

* Read NIXOS_CHANNEL variable

* Check channel

* Add channel struct to fix parsing NIXOS_CHANNELS

* Use `eachDefaultSystem` instead of listing them manually

* Add individual dev shells for frontend and backend

* Update .github/workflows/import-to-elasticsearch.yml

Co-authored-by: Naïm Favier <n@monade.li>

* use both development environments by default (as it was)

but still provide devShells for each of the subprojects

* pkgs.lib → lib everywhere

and define lib = nixpkgs.lib before the call to eachDefaultSystem
Also, version = lib.fileContents ./VERSION;

* Update flake.nix

Co-authored-by: Naïm Favier <n@monade.li>

* typo

* bumping version to test the changes to import-to-elasticsearch github action

* some invisibile characters needed to be removed

* typo

* will this work

* typo

* forgot the checkout step

* add some debugging

* typo

* read NIXOS_CHANNELS from environment not via argument

* fix for the NIXOS_CHANNELS variable

Co-authored-by: Janne Heß <janne@hess.ooo>
Co-authored-by: ysndr <me@ysndr.de>
Co-authored-by: Naïm Favier <n@monade.li>

.github/workflows/import-to-elasticsearch.yml

@@ -7,15 +7,36 @@ on:
 
 jobs:
 
+  nixos-channels:
+    runs-on: ubuntu-latest
+
+    outputs:
+      matrix: ${{ steps.nixos-channels.outputs.matrix }}
+
+    steps:
+    - name: Checking out the repository
+      uses: actions/checkout@v3
+
+    - name: Setup
+      uses: ./.github/actions/common-setup
+      with:
+        CACHIX_SIGNING_KEY: ${{ secrets.CACHIX_SIGNING_KEY }}
+
+    - name: NixOS Channels
+      id: nixos-channels
+      run: |
+        nix build -L .#nixosChannels
+        channels="{\"channel\": $(< ./result)}"
+        echo $channels
+        echo "::set-output name=matrix::$channels"
+
   import-nixpkgs:
+    needs: nixos-channels
     runs-on: ubuntu-latest
 
     strategy:
       fail-fast: false
-      matrix:
+      matrix: ${{ fromJSON(needs.nixos-channels.outputs.matrix) }}
-        channel:
-          - unstable
-          - 21.11
 
     env:
       RUST_LOG: debug
@@ -46,7 +67,6 @@ jobs:
       if: github.repository_owner == 'NixOS'
 
 
-
   import-flakes:
     runs-on: ubuntu-latest
 

VERSION

@@ -1 +1 @@
-29
+30

flake-info/default.nix

@@ -1,5 +1,7 @@
-{ pkgs ? import <nixpkgs> { } }: with pkgs;
+{ pkgs ? import <nixpkgs> {}
-rustPlatform.buildRustPackage rec {
+, nixosChannels ? {}
+}:
+pkgs.rustPlatform.buildRustPackage rec {
   name = "flake-info";
   src = ./.;
   cargoLock = {
@@ -8,11 +10,18 @@ rustPlatform.buildRustPackage rec {
       "elasticsearch-8.0.0-alpha.1" = "sha256-gjmk3Q3LTAvLhzQ+k1knSp1HBwtqNiubjXNnLy/cS5M=";
     };
   };
-  nativeBuildInputs = [ pkg-config ];
+  nativeBuildInputs = with pkgs; [ pkg-config ];
-  buildInputs = [ openssl openssl.dev makeWrapper ] 
+  buildInputs =
-              ++ lib.optional pkgs.stdenv.isDarwin [ libiconv darwin.apple_sdk.frameworks.Security ];
+    with pkgs; [
+      openssl
+      openssl.dev
+      makeWrapper
+    ] ++ lib.optional pkgs.stdenv.isDarwin [
+      libiconv
+      darwin.apple_sdk.frameworks.Security
+    ];
   
-  checkInputs = [ pandoc ];
+  checkInputs = with pkgs; [ pandoc ];
   
   NIXPKGS_PANDOC_FILTERS_PATH = "${pkgs.path + "/doc/build-aux/pandoc-filters"}";
 
@@ -24,6 +33,7 @@ rustPlatform.buildRustPackage rec {
   postInstall = ''
     wrapProgram $out/bin/flake-info \
       --set NIXPKGS_PANDOC_FILTERS_PATH "${NIXPKGS_PANDOC_FILTERS_PATH}" \
-      --prefix PATH : ${pandoc}/bin
+      --set NIXOS_CHANNELS '${builtins.toJSON nixosChannels}' \
+      --prefix PATH : ${pkgs.pandoc}/bin
   '';
 }

flake-info/src/bin/flake-info.rs

@@ -5,11 +5,14 @@ use flake_info::data::import::{Kind, NixOption};
 use flake_info::data::{self, Export, Nixpkgs, Source};
 use flake_info::elastic::{ElasticsearchError, ExistsStrategy};
 use flake_info::{commands, elastic};
+use lazy_static::lazy_static;
 use log::{debug, error, info, warn};
 use semver::VersionReq;
+use serde::Deserialize;
 use sha2::Digest;
 use std::path::{Path, PathBuf};
 use std::ptr::hash;
+use std::str::FromStr;
 use std::{fs, io};
 use structopt::{clap::ArgGroup, StructOpt};
 use thiserror::Error;
@@ -198,6 +201,9 @@ enum FlakeInfoError {
     #[error("Nix check failed: {0}")]
     NixCheck(#[from] NixCheckError),
 
+    #[error("Nixos Channel `{0}` not among the allowed Channels set by NIXOS_CHANNELS ({:?}", .1.channels)]
+    UnknownNixOSChannel(String, NixosChannels),
+
     #[error("Getting flake info caused an error: {0:?}")]
     Flake(anyhow::Error),
     #[error("Getting nixpkgs info caused an error: {0:?}")]
@@ -237,6 +243,8 @@ async fn run_command(
             Ok((exports, ident))
         }
         Command::Nixpkgs { channel } => {
+            NIXOS_CHANNELS.check_channel(&channel)?;
+
             let nixpkgs = Source::nixpkgs(channel)
                 .await
                 .map_err(FlakeInfoError::Nixpkgs)?;
@@ -251,6 +259,8 @@ async fn run_command(
             Ok((exports, ident))
         }
         Command::NixpkgsArchive { source, channel } => {
+            NIXOS_CHANNELS.check_channel(&channel)?;
+
             let ident = (
                 "nixos".to_string(),
                 channel.to_owned(),
@@ -404,3 +414,36 @@ async fn push_to_elastic(
 
     Ok(())
 }
+
+/// Information about allowed and default nixos channels.
+/// Typyically passed by environment variable NIXOS_CHANNELS.
+/// Used to filter the input arguments for `flake-info nixpkgs` and `flake-info nixpkgs-archive`
+#[derive(Clone, Debug, Deserialize)]
+struct NixosChannels {
+    channels: Vec<Channel>,
+}
+
+#[derive(Clone, Debug, Deserialize)]
+struct Channel {
+    branch: String
+}
+
+impl NixosChannels {
+    fn check_channel(&self, channel: &String) -> Result<(), FlakeInfoError> {
+        self.channels.iter().find(|c| &c.branch == channel).map_or_else(|| Ok(()), |_| Err(FlakeInfoError::UnknownNixOSChannel(channel.clone(), self.clone())))
+    }
+}
+
+impl FromStr for NixosChannels {
+    type Err=serde_json::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        serde_json::from_str(s)
+    }
+}
+
+lazy_static! {
+    static ref NIXOS_CHANNELS: NixosChannels = std::env::var("NIXOS_CHANNELS")
+        .unwrap_or("".to_string())
+        .parse().unwrap();
+}

flake.lock

@@ -15,6 +15,22 @@
         "type": "github"
       }
     },
+    "nixos-org-configurations": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1648674978,
+        "narHash": "sha256-7lVlPb9/Lu3M9xPzwdvtgqkeQI4FAMv+T3v+yT54ZZ0=",
+        "owner": "NixOS",
+        "repo": "nixos-org-configurations",
+        "rev": "76c0687ac275235142dae7c855aab2885302298c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixos-org-configurations",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1650701402,
@@ -33,6 +49,7 @@
     "root": {
       "inputs": {
         "flake-utils": "flake-utils",
+        "nixos-org-configurations": "nixos-org-configurations",
         "nixpkgs": "nixpkgs"
       }
     }

flake.nix

@@ -6,33 +6,116 @@
 
   inputs.nixpkgs.url = "nixpkgs/nixos-unstable";
   inputs.flake-utils.url = "github:numtide/flake-utils";
+  inputs.nixos-org-configurations.url = "github:NixOS/nixos-org-configurations";
+  inputs.nixos-org-configurations.flake = false;
 
   outputs = { self
             , nixpkgs
             , flake-utils
+            , nixos-org-configurations 
             }:
-    flake-utils.lib.eachSystem
+    flake-utils.lib.eachDefaultSystem
-      (with flake-utils.lib.system; [
-        x86_64-linux
-        i686-linux
-        x86_64-darwin
-        aarch64-linux
-      ])
       (system:
         let
           pkgs = nixpkgs.legacyPackages.${system};
-          warnToUpgradeNix = pkgs.lib.warn "Please upgrade Nix to 2.7 or later.";
+          lib = nixpkgs.lib;
+          warnToUpgradeNix = lib.warn "Please upgrade Nix to 2.7 or later.";
+          version = lib.fileContents ./VERSION;
+          nixosChannels =
+            let
+              allChannels = (import "${nixos-org-configurations}/channels.nix").channels;
+              filteredChannels =
+                lib.filterAttrs
+                  (n: v:
+                    builtins.elem v.status ["beta" "stable" "rolling"] &&
+                    lib.hasPrefix "nixos-" n &&
+                    v ? variant && v.variant == "primary"
+                  )
+                  allChannels;
+            in
+            {
+              channels =
+                lib.mapAttrsToList
+                  (n: v:
+                    {
+                      id = lib.removePrefix "nixos-" n;
+                      status = v.status;
+                      jobset =
+                        builtins.concatStringsSep
+                          "/"
+                          (lib.init (lib.splitString "/" v.job));
+                      branch = n;
+                    }
+                  )
+                  filteredChannels;
+              default =
+                builtins.head
+                  (builtins.sort (e1: e2: ! (builtins.lessThan e1 e2))
+                    (builtins.map
+                      (lib.removePrefix "nixos-")
+                      (builtins.attrNames
+                        (lib.filterAttrs (_: v: v.status == "stable") filteredChannels)
+                      )
+                    )
+                  );
+            };
+          nixosChannelsFile = pkgs.runCommand "nixosChannels.json" {} ''
+            echo '${builtins.toJSON (builtins.map (c: c.id) nixosChannels.channels)}' > $out
+          '';
+
+          mkDevShell = { inputsFrom ? [], extraPackages ? [], extraShellHook ? "" }: 
+            pkgs.mkShell {
+              inherit inputsFrom;
+              packages = extraPackages;
+              shellHook = ''
+                export NIXOS_CHANNELS='${builtins.toJSON nixosChannels}';
+                export ELASTICSEARCH_MAPPING_SCHEMA_VERSION="${version}";
+              '' + extraShellHook;
+            };
         in rec {
 
           packages.default = packages.flake-info;
-          packages.flake-info = import ./flake-info { inherit pkgs; };
+          packages.flake-info = import ./flake-info { inherit pkgs nixosChannels; };
-          packages.frontend = import ./frontend { inherit pkgs; };
+          packages.frontend = import ./frontend { inherit pkgs nixosChannels version; };
+          packages.nixosChannels = nixosChannelsFile;
 
-          devShells.default = pkgs.mkShell {
+          devShells.default = mkDevShell {
-            inputsFrom = builtins.attrValues packages;
+            inputsFrom = [
-            shellHook = ''
+              packages.flake-info
+              packages.frontend
+            ];
+            extraPackages = [pkgs.rustfmt];
+            extraShellHook = ''
               export RUST_SRC_PATH="${pkgs.rustPlatform.rustLibSrc}";
               export NIXPKGS_PANDOC_FILTERS_PATH="${packages.flake-info.NIXPKGS_PANDOC_FILTERS_PATH}";
+              export PATH=$PWD/frontend/node_modules/.bin:$PATH
+
+              rm -rf frontend/node_modules
+              ln -sf ${packages.frontend.yarnPkg}/libexec/${(builtins.parseDrvName packages.frontend.name).name}/node_modules frontend/
+              echo "========================================================"
+              echo "= To develop the frontend run: cd frontend && yarn dev ="
+              echo "========================================================"
+            '';
+          };
+
+          devShells.flake-info = mkDevShell {
+            inputsFrom = [packages.flake-info];
+            extraPackages = [pkgs.rustfmt];
+            extraShellHook = ''
+              export RUST_SRC_PATH="${pkgs.rustPlatform.rustLibSrc}";
+              export NIXPKGS_PANDOC_FILTERS_PATH="${packages.flake-info.NIXPKGS_PANDOC_FILTERS_PATH}";
+            '';
+          };
+
+          devShells.frontend = mkDevShell {
+            inputsFrom = [packages.frontend] ;
+            extraShellHook = ''
+              export PATH=$PWD/frontend/node_modules/.bin:$PATH
+              rm -rf frontend/node_modules
+              ln -sf ${packages.frontend.yarnPkg}/libexec/${(builtins.parseDrvName packages.frontend.name).name}/node_modules frontend/
+              echo "========================================================"
+              echo "= To develop the frontend run: cd frontend && yarn dev ="
+              echo "========================================================"
             '';
           };
 

frontend/default.nix

@@ -1,5 +1,6 @@
 { pkgs ? import <nixpkgs> { }
-, version ? pkgs.lib.removeSuffix "\n" (builtins.readFile ../VERSION)
+, nixosChannels
+, version
 }:
 let
   package = builtins.fromJSON (builtins.readFile ./package.json);
@@ -52,6 +53,9 @@ pkgs.stdenv.mkDerivation {
       elm-analyse
     ]);
 
+  ELASTICSEARCH_MAPPING_SCHEMA_VERSION = version;
+  NIXOS_CHANNELS = builtins.toJSON nixosChannels;
+
   configurePhase = pkgs.elmPackages.fetchElmDeps {
     elmPackages = import ./elm-srcs.nix;
     elmVersion = pkgs.elmPackages.elm.version;
@@ -66,7 +70,6 @@ pkgs.stdenv.mkDerivation {
   buildPhase = ''
     # Yarn writes cache directories etc to $HOME.
     export HOME=$PWD/yarn_home
-    sed -i -e "s|process.env.ELASTICSEARCH_MAPPING_SCHEMA_VERSION|${version}|" src/index.js
     yarn prod
   '';
 
@@ -75,14 +78,6 @@ pkgs.stdenv.mkDerivation {
     cp -R ./dist/* $out/
     cp netlify.toml $out/
   '';
-  shellHook = ''
-    rm -rf frontend/node_modules
-    ln -sf ${yarnPkg}/libexec/${package.name}/node_modules frontend/
-    export PATH=$PWD/frontend/node_modules/.bin:$PATH
-    export ELASTICSEARCH_MAPPING_SCHEMA_VERSION=${version}
-    echo "============================"
-    echo "= To develop the frontend run: cd frontend && yarn dev ="
-    echo "============================"
-  '';
 
+  passthru.yarnPkg = yarnPkg;
 }

frontend/src/Main.elm

@@ -25,13 +25,20 @@ import Html.Attributes
         , id
         , src
         )
+import Json.Decode
 import Page.Flakes exposing (Model(..))
 import Page.Home
 import Page.Options
 import Page.Packages
 import RemoteData exposing (RemoteData(..))
 import Route exposing (SearchType(..))
-import Search exposing (Msg(..), defaultFlakeId)
+import Search
+    exposing
+        ( Msg(..)
+        , NixOSChannel
+        , decodeNixOSChannels
+        , defaultFlakeId
+        )
 import Url
 
 
@@ -44,6 +51,7 @@ type alias Flags =
     , elasticsearchUrl : String
     , elasticsearchUsername : String
     , elasticsearchPassword : String
+    , nixosChannels : Json.Decode.Value
     }
 
 
@@ -51,6 +59,8 @@ type alias Model =
     { navKey : Browser.Navigation.Key
     , route : Route.Route
     , elasticsearch : Search.Options
+    , defaultNixOSChannel : String
+    , nixosChannels : List NixOSChannel
     , page : Page
     }
 
@@ -70,6 +80,14 @@ init :
     -> ( Model, Cmd Msg )
 init flags url navKey =
     let
+        nixosChannels =
+            case Json.Decode.decodeValue decodeNixOSChannels flags.nixosChannels of
+                Ok c ->
+                    c
+
+                Err _ ->
+                    { default = "", channels = [] }
+
         model =
             { navKey = navKey
             , elasticsearch =
@@ -78,6 +96,8 @@ init flags url navKey =
                     flags.elasticsearchUrl
                     flags.elasticsearchUsername
                     flags.elasticsearchPassword
+            , defaultNixOSChannel = nixosChannels.default
+            , nixosChannels = nixosChannels.channels
             , page = NotFound
             , route = Route.Home
             }
@@ -127,6 +147,7 @@ attemptQuery (( model, _ ) as pair) =
                         , Cmd.map msg <|
                             makeRequest
                                 model.elasticsearch
+                                model.nixosChannels
                                 searchModel.searchType
                                 searchModel.channel
                                 (Maybe.withDefault "" searchModel.query)
@@ -239,7 +260,7 @@ changeRouteTo currentModel url =
                                 _ ->
                                     Nothing
                     in
-                    Page.Packages.init searchArgs modelPage
+                    Page.Packages.init searchArgs currentModel.defaultNixOSChannel currentModel.nixosChannels modelPage
                         |> updateWith Packages PackagesMsg model
                         |> avoidReinit
                         |> attemptQuery
@@ -254,7 +275,7 @@ changeRouteTo currentModel url =
                                 _ ->
                                     Nothing
                     in
-                    Page.Options.init searchArgs modelPage
+                    Page.Options.init searchArgs currentModel.defaultNixOSChannel currentModel.nixosChannels modelPage
                         |> updateWith Options OptionsMsg model
                         |> avoidReinit
                         |> attemptQuery
@@ -269,7 +290,7 @@ changeRouteTo currentModel url =
                                 _ ->
                                     Nothing
                     in
-                    Page.Flakes.init searchArgs modelPage
+                    Page.Flakes.init searchArgs currentModel.defaultNixOSChannel currentModel.nixosChannels modelPage
                         |> updateWith Flakes FlakesMsg model
                         |> avoidReinit
                         |> attemptQuery
@@ -300,19 +321,19 @@ update msg model =
             changeRouteTo model url
 
         ( HomeMsg subMsg, Home subModel ) ->
-            Page.Home.update subMsg subModel
+            Page.Home.update subMsg subModel model.nixosChannels
                 |> updateWith Home HomeMsg model
 
         ( PackagesMsg subMsg, Packages subModel ) ->
-            Page.Packages.update model.navKey subMsg subModel
+            Page.Packages.update model.navKey subMsg subModel model.nixosChannels
                 |> updateWith Packages PackagesMsg model
 
         ( OptionsMsg subMsg, Options subModel ) ->
-            Page.Options.update model.navKey subMsg subModel
+            Page.Options.update model.navKey subMsg subModel model.nixosChannels
                 |> updateWith Options OptionsMsg model
 
         ( FlakesMsg subMsg, Flakes subModel ) ->
-            Page.Flakes.update model.navKey subMsg subModel
+            Page.Flakes.update model.navKey subMsg subModel model.nixosChannels
                 |> updateWith Flakes FlakesMsg model
 
         ( _, _ ) ->
@@ -436,13 +457,13 @@ viewPage model =
             div [] [ text "Welcome" ]
 
         Packages packagesModel ->
-            Html.map (\m -> PackagesMsg m) <| Page.Packages.view packagesModel
+            Html.map (\m -> PackagesMsg m) <| Page.Packages.view model.nixosChannels packagesModel
 
         Options optionsModel ->
-            Html.map (\m -> OptionsMsg m) <| Page.Options.view optionsModel
+            Html.map (\m -> OptionsMsg m) <| Page.Options.view model.nixosChannels optionsModel
 
         Flakes flakesModel ->
-            Html.map (\m -> FlakesMsg m) <| Page.Flakes.view flakesModel
+            Html.map (\m -> FlakesMsg m) <| Page.Flakes.view model.nixosChannels flakesModel
 
 
 

frontend/src/Page/Flakes.elm

@@ -35,6 +35,7 @@ import Route
 import Search
     exposing
         ( Msg(..)
+        , NixOSChannel
         , viewFlakes
         , viewResult
         , viewSearchInput
@@ -50,8 +51,13 @@ type Model
     | PackagesModel Page.Packages.Model
 
 
-init : Route.SearchArgs -> Maybe Model -> ( Model, Cmd Msg )
+init :
-init searchArgs model =
+    Route.SearchArgs
+    -> String
+    -> List NixOSChannel
+    -> Maybe Model
+    -> ( Model, Cmd Msg )
+init searchArgs defaultNixOSChannel nixosChannels model =
     let
         --  init with respective module or with packages by default
         searchType =
@@ -60,10 +66,14 @@ init searchArgs model =
         mapEitherModel m =
             case ( searchType, m ) of
                 ( OptionSearch, OptionModel model_ ) ->
-                    Tuple.mapBoth OptionModel (Cmd.map OptionsMsg) <| Page.Options.init searchArgs <| Just model_
+                    Tuple.mapBoth OptionModel (Cmd.map OptionsMsg) <|
+                        Page.Options.init searchArgs defaultNixOSChannel nixosChannels <|
+                            Just model_
 
                 ( PackageSearch, PackagesModel model_ ) ->
-                    Tuple.mapBoth PackagesModel (Cmd.map PackagesMsg) <| Page.Packages.init searchArgs <| Just model_
+                    Tuple.mapBoth PackagesModel (Cmd.map PackagesMsg) <|
+                        Page.Packages.init searchArgs defaultNixOSChannel nixosChannels <|
+                            Just model_
 
                 _ ->
                     default
@@ -71,10 +81,12 @@ init searchArgs model =
         default =
             case searchType of
                 PackageSearch ->
-                    Tuple.mapBoth PackagesModel (Cmd.map PackagesMsg) <| Page.Packages.init searchArgs Nothing
+                    Tuple.mapBoth PackagesModel (Cmd.map PackagesMsg) <|
+                        Page.Packages.init searchArgs defaultNixOSChannel nixosChannels Nothing
 
                 OptionSearch ->
-                    Tuple.mapBoth OptionModel (Cmd.map OptionsMsg) <| Page.Options.init searchArgs Nothing
+                    Tuple.mapBoth OptionModel (Cmd.map OptionsMsg) <|
+                        Page.Options.init searchArgs defaultNixOSChannel nixosChannels Nothing
 
         ( newModel, newCmd ) =
             Maybe.withDefault default <| Maybe.map mapEitherModel model
@@ -97,8 +109,9 @@ update :
     Browser.Navigation.Key
     -> Msg
     -> Model
+    -> List NixOSChannel
     -> ( Model, Cmd Msg )
-update navKey msg model =
+update navKey msg model nixosChannels =
     case ( msg, model ) of
         ( OptionsMsg msg_, OptionModel model_ ) ->
             case msg_ of
@@ -110,6 +123,7 @@ update navKey msg model =
                                 navKey
                                 subMsg
                                 model_
+                                nixosChannels
                     in
                     ( newModel, Cmd.map Page.Options.SearchMsg newCmd ) |> Tuple.mapBoth OptionModel (Cmd.map OptionsMsg)
 
@@ -123,6 +137,7 @@ update navKey msg model =
                                 navKey
                                 subMsg
                                 model_
+                                nixosChannels
                     in
                     ( newModel, Cmd.map Page.Packages.SearchMsg newCmd ) |> Tuple.mapBoth PackagesModel (Cmd.map PackagesMsg)
 
@@ -134,8 +149,11 @@ update navKey msg model =
 -- VIEW
 
 
-view : Model -> Html Msg
+view :
-view model =
+    List NixOSChannel
+    -> Model
+    -> Html Msg
+view nixosChannels model =
     let
         resultStatus result =
             case result of
@@ -172,8 +190,8 @@ view model =
                     )
                 )
                 [ h1 [] bodyTitle
-                , viewSearchInput outMsg categoryName Nothing model_.query
+                , viewSearchInput nixosChannels outMsg categoryName Nothing model_.query
-                , viewResult outMsg Route.Flakes categoryName model_ viewSuccess viewBuckets <|
+                , viewResult nixosChannels outMsg Route.Flakes categoryName model_ viewSuccess viewBuckets <|
                     viewFlakes outMsg model_.channel model_.searchType
                 ]
 
@@ -194,6 +212,7 @@ view model =
 
 makeRequest :
     Search.Options
+    -> List NixOSChannel
     -> SearchType
     -> String
     -> String
@@ -202,13 +221,14 @@ makeRequest :
     -> Maybe String
     -> Search.Sort
     -> Cmd Msg
-makeRequest options searchType index_id query from size maybeBuckets sort =
+makeRequest options nixosChannels searchType index_id query from size maybeBuckets sort =
     let
         cmd =
             case searchType of
                 PackageSearch ->
                     Search.makeRequest
                         (makeRequestBody searchType query from size maybeBuckets sort)
+                        nixosChannels
                         index_id
                         Page.Packages.decodeResultItemSource
                         Page.Packages.decodeResultAggregations
@@ -221,6 +241,7 @@ makeRequest options searchType index_id query from size maybeBuckets sort =
                 OptionSearch ->
                     Search.makeRequest
                         (makeRequestBody searchType query from size maybeBuckets sort)
+                        nixosChannels
                         index_id
                         Page.Options.decodeResultItemSource
                         Page.Options.decodeResultAggregations

frontend/src/Page/Home.elm

@@ -1,6 +1,7 @@
 module Page.Home exposing (Model, Msg, init, update, view)
 
 import Html exposing (Html, div, text)
+import Search exposing (NixOSChannel)
 
 
 
@@ -24,8 +25,12 @@ type Msg
     = NoOp
 
 
-update : Msg -> Model -> ( Model, Cmd Msg )
+update :
-update msg model =
+    Msg
+    -> Model
+    -> List NixOSChannel
+    -> ( Model, Cmd Msg )
+update msg model _ =
     case msg of
         NoOp ->
             ( model, Cmd.none )

frontend/src/Page/Options.elm

@@ -45,7 +45,12 @@ import Http exposing (Body)
 import Json.Decode
 import Json.Decode.Pipeline
 import Route exposing (SearchType)
-import Search exposing (Details, decodeResolvedFlake)
+import Search
+    exposing
+        ( Details
+        , NixOSChannel
+        , decodeResolvedFlake
+        )
 
 
 
@@ -82,11 +87,16 @@ type alias AggregationsAll =
     }
 
 
-init : Route.SearchArgs -> Maybe Model -> ( Model, Cmd Msg )
+init :
-init searchArgs model =
+    Route.SearchArgs
+    -> String
+    -> List NixOSChannel
+    -> Maybe Model
+    -> ( Model, Cmd Msg )
+init searchArgs defaultNixOSChannel nixosChannels model =
     let
         ( newModel, newCmd ) =
-            Search.init searchArgs model
+            Search.init searchArgs defaultNixOSChannel nixosChannels model
     in
     ( newModel
     , Cmd.map SearchMsg newCmd
@@ -105,8 +115,9 @@ update :
     Browser.Navigation.Key
     -> Msg
     -> Model
+    -> List NixOSChannel
     -> ( Model, Cmd Msg )
-update navKey msg model =
+update navKey msg model nixosChannels =
     case msg of
         SearchMsg subMsg ->
             let
@@ -116,6 +127,7 @@ update navKey msg model =
                         navKey
                         subMsg
                         model
+                        nixosChannels
             in
             ( newModel, Cmd.map SearchMsg newCmd )
 
@@ -124,12 +136,16 @@ update navKey msg model =
 -- VIEW
 
 
-view : Model -> Html Msg
+view :
-view model =
+    List NixOSChannel
+    -> Model
+    -> Html Msg
+view nixosChannels model =
     Search.view { toRoute = Route.Options, categoryName = "options" }
         [ text "Search more than "
         , strong [] [ text "10 000 options" ]
         ]
+        nixosChannels
         model
         viewSuccess
         viewBuckets
@@ -146,26 +162,28 @@ viewBuckets _ _ =
 
 
 viewSuccess :
-    String
+    List NixOSChannel
+    -> String
     -> Details
     -> Maybe String
     -> List (Search.ResultItem ResultItemSource)
     -> Html Msg
-viewSuccess channel showInstallDetails show hits =
+viewSuccess nixosChannels channel showInstallDetails show hits =
     ul []
         (List.map
-            (viewResultItem channel showInstallDetails show)
+            (viewResultItem nixosChannels channel showInstallDetails show)
             hits
         )
 
 
 viewResultItem :
-    String
+    List NixOSChannel
+    -> String
     -> Details
     -> Maybe String
     -> Search.ResultItem ResultItemSource
     -> Html Msg
-viewResultItem channel _ show item =
+viewResultItem nixosChannels channel _ show item =
     let
         showHtml value =
             case Html.Parser.run <| String.trim value of
@@ -229,7 +247,7 @@ viewResultItem channel _ show item =
                                     |> Maybe.withDefault []
                                )
                             ++ [ div [] [ text "Declared in" ]
-                               , div [] <| findSource channel item.source
+                               , div [] <| findSource nixosChannels channel item.source
                                ]
 
             else
@@ -283,8 +301,12 @@ viewResultItem channel _ show item =
             ]
 
 
-findSource : String -> ResultItemSource -> List (Html a)
+findSource :
-findSource channel source =
+    List NixOSChannel
+    -> String
+    -> ResultItemSource
+    -> List (Html a)
+findSource nixosChannels channel source =
     let
         githubUrlPrefix branch =
             "https://github.com/NixOS/nixpkgs/blob/" ++ branch ++ "/"
@@ -297,7 +319,7 @@ findSource channel source =
                 value
 
         asGithubLink value =
-            case Search.channelDetailsFromId channel of
+            case List.head (List.filter (\x -> x.id == channel) nixosChannels) of
                 Just channelDetails ->
                     a
                         [ href <| githubUrlPrefix channelDetails.branch ++ (value |> String.replace ":" "#L")
@@ -342,6 +364,7 @@ findSource channel source =
 
 makeRequest :
     Search.Options
+    -> List NixOSChannel
     -> SearchType
     -> String
     -> String
@@ -350,9 +373,10 @@ makeRequest :
     -> Maybe String
     -> Search.Sort
     -> Cmd Msg
-makeRequest options _ channel query from size _ sort =
+makeRequest options nixosChannels _ channel query from size _ sort =
     Search.makeRequest
         (makeRequestBody query from size sort)
+        nixosChannels
         channel
         decodeResultItemSource
         decodeResultAggregations

frontend/src/Page/Packages.elm

@@ -51,6 +51,7 @@ import Route exposing (Route(..), SearchType)
 import Search
     exposing
         ( Details(..)
+        , NixOSChannel
         , decodeResolvedFlake
         , viewBucket
         )
@@ -162,11 +163,16 @@ initBuckets bucketsAsString =
         |> Maybe.withDefault emptyBuckets
 
 
-init : Route.SearchArgs -> Maybe Model -> ( Model, Cmd Msg )
+init :
-init searchArgs model =
+    Route.SearchArgs
+    -> String
+    -> List NixOSChannel
+    -> Maybe Model
+    -> ( Model, Cmd Msg )
+init searchArgs defaultNixOSChannel nixosChannels model =
     let
         ( newModel, newCmd ) =
-            Search.init searchArgs model
+            Search.init searchArgs defaultNixOSChannel nixosChannels model
     in
     ( newModel
     , Cmd.map SearchMsg newCmd
@@ -195,8 +201,9 @@ update :
     Browser.Navigation.Key
     -> Msg
     -> Model
+    -> List NixOSChannel
     -> ( Model, Cmd Msg )
-update navKey msg model =
+update navKey msg model nixosChannels =
     case msg of
         SearchMsg subMsg ->
             let
@@ -206,6 +213,7 @@ update navKey msg model =
                         navKey
                         subMsg
                         model
+                        nixosChannels
             in
             ( newModel, Cmd.map SearchMsg newCmd )
 
@@ -214,12 +222,16 @@ update navKey msg model =
 -- VIEW
 
 
-view : Model -> Html Msg
+view :
-view model =
+    List NixOSChannel
+    -> Model
+    -> Html Msg
+view nixosChannels model =
     Search.view { toRoute = Route.Packages, categoryName = "packages" }
         [ text "Search more than "
         , strong [] [ text "80 000 packages" ]
         ]
+        nixosChannels
         model
         viewSuccess
         viewBuckets
@@ -282,26 +294,28 @@ filterPlatformsBucket =
 
 
 viewSuccess :
-    String
+    List NixOSChannel
+    -> String
     -> Details
     -> Maybe String
     -> List (Search.ResultItem ResultItemSource)
     -> Html Msg
-viewSuccess channel showInstallDetails show hits =
+viewSuccess nixosChannels channel showInstallDetails show hits =
     ul []
         (List.map
-            (viewResultItem channel showInstallDetails show)
+            (viewResultItem nixosChannels channel showInstallDetails show)
             hits
         )
 
 
 viewResultItem :
-    String
+    List NixOSChannel
+    -> String
     -> Details
     -> Maybe String
     -> Search.ResultItem ResultItemSource
     -> Html Msg
-viewResultItem channel showInstallDetails show item =
+viewResultItem nixosChannels channel showInstallDetails show item =
     let
         optionals b l =
             if b then
@@ -368,7 +382,7 @@ viewResultItem channel showInstallDetails show item =
                                         )
                                     |> Maybe.withDefault []
                                )
-                            ++ renderSource item channel trapClick createShortDetailsItem createGithubUrl
+                            ++ renderSource item nixosChannels channel trapClick createShortDetailsItem createGithubUrl
                             ++ (let
                                     licenses =
                                         item.source.licenses
@@ -450,7 +464,7 @@ viewResultItem channel showInstallDetails show item =
                 ]
 
         showPlatform platform =
-            case Search.channelDetailsFromId channel of
+            case List.head (List.filter (\x -> x.id == channel) nixosChannels) of
                 Just channelDetails ->
                     let
                         url =
@@ -650,8 +664,23 @@ viewResultItem channel showInstallDetails show item =
         )
 
 
-renderSource : Search.ResultItem ResultItemSource -> String -> Html.Attribute Msg -> (String -> String -> Html Msg) -> (String -> String -> String) -> List (Html Msg)
+renderSource :
-renderSource item channel trapClick createShortDetailsItem createGithubUrl =
+    Search.ResultItem ResultItemSource
+    -> List NixOSChannel
+    -> String
+    -> Html.Attribute Msg
+    ->
+        (String
+         -> String
+         -> Html Msg
+        )
+    ->
+        (String
+         -> String
+         -> String
+        )
+    -> List (Html Msg)
+renderSource item nixosChannels channel trapClick createShortDetailsItem createGithubUrl =
     let
         makeLink text url =
             [ li [ trapClick ] [ createShortDetailsItem text url ] ]
@@ -660,7 +689,7 @@ renderSource item channel trapClick createShortDetailsItem createGithubUrl =
             item.source.position
                 |> Maybe.map
                     (\pos ->
-                        case Search.channelDetailsFromId channel of
+                        case List.head (List.filter (\x -> x.id == channel) nixosChannels) of
                             Nothing ->
                                 []
 
@@ -684,6 +713,7 @@ renderSource item channel trapClick createShortDetailsItem createGithubUrl =
 
 makeRequest :
     Search.Options
+    -> List NixOSChannel
     -> SearchType
     -> String
     -> String
@@ -692,9 +722,10 @@ makeRequest :
     -> Maybe String
     -> Search.Sort
     -> Cmd Msg
-makeRequest options _ channel query from size maybeBuckets sort =
+makeRequest options nixosChannels _ channel query from size maybeBuckets sort =
     Search.makeRequest
         (makeRequestBody query from size maybeBuckets sort)
+        nixosChannels
         channel
         decodeResultItemSource
         decodeResultAggregations

frontend/src/Search.elm

@@ -4,15 +4,16 @@ module Search exposing
     , Details(..)
     , Model
     , Msg(..)
+    , NixOSChannel
+    , NixOSChannelStatus
     , Options
     , ResultHits
     , ResultItem
     , SearchResult
     , Sort(..)
-    , channelDetailsFromId
-    , channels
     , closeButton
     , decodeAggregation
+    , decodeNixOSChannels
     , decodeResolvedFlake
     , decodeResult
     , defaultFlakeId
@@ -153,6 +154,68 @@ type Sort
     | AlphabeticallyDesc
 
 
+type alias NixOSChannels =
+    { default : String
+    , channels : List NixOSChannel
+    }
+
+
+type alias NixOSChannel =
+    { id : String
+    , status : NixOSChannelStatus
+    , jobset : String
+    , branch : String
+    }
+
+
+type NixOSChannelStatus
+    = Rolling
+    | Stable
+    | Beta
+
+
+channelTitle : NixOSChannel -> String
+channelTitle channel =
+  if channel.status == Beta
+  then channel.id ++ " (Beta)"
+  else channel.id
+
+
+decodeNixOSChannels : Json.Decode.Decoder NixOSChannels
+decodeNixOSChannels =
+    Json.Decode.map2 NixOSChannels
+        (Json.Decode.field "default" Json.Decode.string)
+        (Json.Decode.field "channels" (Json.Decode.list decodeNixOSChannel))
+
+
+
+decodeNixOSChannel : Json.Decode.Decoder NixOSChannel
+decodeNixOSChannel =
+    Json.Decode.map4 NixOSChannel
+        (Json.Decode.field "id" Json.Decode.string)
+        (Json.Decode.field "status"
+            (Json.Decode.string
+                |> Json.Decode.andThen
+                    (\status ->
+                        case status of
+                            "rolling" ->
+                                Json.Decode.succeed Rolling
+
+                            "stable" ->
+                                Json.Decode.succeed Stable
+
+                            "beta" ->
+                                Json.Decode.succeed Beta
+
+                            _ ->
+                                Json.Decode.fail ("Unknown status: " ++ status)
+                    )
+            )
+        )
+        (Json.Decode.field "jobset" Json.Decode.string)
+        (Json.Decode.field "branch" Json.Decode.string)
+
+
 type alias ResolvedFlake =
     { type_ : String
     , owner : Maybe String
@@ -206,9 +269,11 @@ decodeResolvedFlake =
 
 init :
     Route.SearchArgs
+    -> String
+    -> List NixOSChannel
     -> Maybe (Model a b)
     -> ( Model a b, Cmd (Msg a b) )
-init args maybeModel =
+init args defaultNixOSChannel nixosChannels maybeModel =
     let
         getField getFn default =
             maybeModel
@@ -216,7 +281,7 @@ init args maybeModel =
                 |> Maybe.withDefault default
 
         modelChannel =
-            getField .channel defaultChannel
+            getField .channel defaultNixOSChannel
 
         modelFrom =
             getField .from 0
@@ -249,7 +314,7 @@ init args maybeModel =
       , showInstallDetails = Unset
       , searchType = Maybe.withDefault Route.PackageSearch args.type_
       }
-        |> ensureLoading
+        |> ensureLoading nixosChannels
     , Browser.Dom.focus "search-query-input" |> Task.attempt (\_ -> NoOp)
     )
 
@@ -262,9 +327,14 @@ shouldLoad model =
 
 
 ensureLoading :
-    Model a b
+    List NixOSChannel
     -> Model a b
-ensureLoading model =
+    -> Model a b
+ensureLoading nixosChannels model =
+    let
+        channels =
+            List.map .id nixosChannels
+    in
     if model.query /= Nothing && model.query /= Just "" && List.member model.channel channels then
         { model | result = RemoteData.Loading }
 
@@ -324,8 +394,9 @@ update :
     -> Browser.Navigation.Key
     -> Msg a b
     -> Model a b
+    -> List NixOSChannel
     -> ( Model a b, Cmd (Msg a b) )
-update toRoute navKey msg model =
+update toRoute navKey msg model nixosChannels =
     case msg of
         NoOp ->
             ( model
@@ -338,7 +409,7 @@ update toRoute navKey msg model =
                 , show = Nothing
                 , from = 0
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         ToggleSort ->
@@ -359,7 +430,7 @@ update toRoute navKey msg model =
                 , show = Nothing
                 , from = 0
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         ChannelChange channel ->
@@ -369,7 +440,7 @@ update toRoute navKey msg model =
                 , buckets = Nothing
                 , from = 0
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         FlakeChange flake ->
@@ -379,7 +450,7 @@ update toRoute navKey msg model =
                 , buckets = Nothing
                 , from = 0
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         SubjectChange subject ->
@@ -389,7 +460,7 @@ update toRoute navKey msg model =
                 , buckets = Nothing
                 , from = 0
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         QueryInput query ->
@@ -403,7 +474,7 @@ update toRoute navKey msg model =
                 , show = Nothing
                 , buckets = Nothing
             }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         QueryResponse result ->
@@ -426,7 +497,7 @@ update toRoute navKey msg model =
 
         ChangePage from ->
             { model | from = from }
-                |> ensureLoading
+                |> ensureLoading nixosChannels
                 |> pushUrl toRoute navKey
 
         ShowInstallDetails details ->
@@ -470,123 +541,11 @@ createUrl toRoute model =
 -- VIEW
 
 
-type Channel
-    = Unstable
-    | Release_21_11
-
-
-{-| TODO: we should consider using more dynamic approach here
-and load channels from apis similar to what status page does
--}
-type alias ChannelDetails =
-    { id : String
-    , title : String
-    , jobset : String
-    , branch : String
-    }
-
-
-defaultChannel : String
-defaultChannel =
-    "21.11"
-
-
-channelDetails : Channel -> ChannelDetails
-channelDetails channel =
-    case channel of
-        Unstable ->
-            ChannelDetails "unstable" "unstable" "nixos/trunk-combined" "nixos-unstable"
-
-        Release_21_11 ->
-            ChannelDetails "21.11" "21.11" "nixos/release-21.11" "nixos-21.11"
-
-
-channelFromId : String -> Maybe Channel
-channelFromId channel_id =
-    case channel_id of
-        "unstable" ->
-            Just Unstable
-
-        "21.11" ->
-            Just Release_21_11
-
-        _ ->
-            Nothing
-
-
-channelDetailsFromId : String -> Maybe ChannelDetails
-channelDetailsFromId channel_id =
-    channelFromId channel_id
-        |> Maybe.map channelDetails
-
-
-channels : List String
-channels =
-    [ "21.11"
-    , "unstable"
-    ]
-
-
 defaultFlakeId : String
 defaultFlakeId =
     "group-manual"
 
 
-
--- flakeFromId : String -> Maybe Flake
--- flakeFromId flake_id =
---     let
---         find : String -> List Flake -> Maybe Flake
---         find id_ list =
---             case list of
---                 flake :: rest ->
---                     if flake.id == id_ then
---                         Just flake
---
---                     else
---                         find id_ rest
---
---                 [] ->
---                     Nothing
---     in
---     find flake_id flakes
---
---
--- flakeIds : List String
--- flakeIds =
---     List.map .id flakes
---
---
--- flakes : List Flake
--- flakes =
---     [ { id = "latest-nixos-21.11-latest"
---       , isNixpkgs = True
---       , title = "Nixpkgs 21.11"
---       , source = ""
---       }
---     , { id = "latest-nixos-21.05-latest"
---       , isNixpkgs = True
---       , title = "Nixpkgs 21.05"
---       , source = ""
---       }
---     , { id = "nixos-21.09-latest"
---       , isNixpkgs = True
---       , title = "Nixpkgs 21.09"
---       , source = ""
---       }
---     , { id = "latest-nixos-unstable"
---       , isNixpkgs = True
---       , title = "Nixpkgs Unstable"
---       , source = ""
---       }
---     , { id = "flakes"
---       , isNixpkgs = False
---       , title = "Public Flakes"
---       , source = ""
---       }
---     ]
-
-
 sortBy : List Sort
 sortBy =
     [ Relevance
@@ -730,9 +689,11 @@ view :
     , categoryName : String
     }
     -> List (Html c)
+    -> List NixOSChannel
     -> Model a b
     ->
-        (String
+        (List NixOSChannel
+         -> String
          -> Details
          -> Maybe String
          -> List (ResultItem a)
@@ -746,7 +707,7 @@ view :
     -> (Msg a b -> c)
     -> List (Html c)
     -> Html c
-view { toRoute, categoryName } title model viewSuccess viewBuckets outMsg searchBuckets =
+view { toRoute, categoryName } title nixosChannels model viewSuccess viewBuckets outMsg searchBuckets =
     let
         resultStatus =
             case model.result of
@@ -773,8 +734,8 @@ view { toRoute, categoryName } title model viewSuccess viewBuckets outMsg search
             )
         )
         [ h1 [] title
-        , viewSearchInput outMsg categoryName (Just model.channel) model.query
+        , viewSearchInput nixosChannels outMsg categoryName (Just model.channel) model.query
-        , viewResult outMsg toRoute categoryName model viewSuccess viewBuckets searchBuckets
+        , viewResult nixosChannels outMsg toRoute categoryName model viewSuccess viewBuckets searchBuckets
         ]
 
 
@@ -810,12 +771,14 @@ viewFlakes outMsg _ selectedCategory =
 
 
 viewResult :
-    (Msg a b -> c)
+    List NixOSChannel
+    -> (Msg a b -> c)
     -> Route.SearchRoute
     -> String
     -> Model a b
     ->
-        (String
+        (List NixOSChannel
+         -> String
          -> Details
          -> Maybe String
          -> List (ResultItem a)
@@ -828,7 +791,7 @@ viewResult :
         )
     -> List (Html c)
     -> Html c
-viewResult outMsg toRoute categoryName model viewSuccess viewBuckets searchBuckets =
+viewResult nixosChannels outMsg toRoute categoryName model viewSuccess viewBuckets searchBuckets =
     case model.result of
         RemoteData.NotAsked ->
             div [] []
@@ -855,14 +818,14 @@ viewResult outMsg toRoute categoryName model viewSuccess viewBuckets searchBucke
                 div [ class "search-results" ]
                     [ ul [ class "search-sidebar" ] <| List.append searchBuckets buckets
                     , div []
-                        (viewResults model result viewSuccess toRoute outMsg categoryName)
+                        (viewResults nixosChannels model result viewSuccess toRoute outMsg categoryName)
                     ]
 
             else
                 div [ class "search-results" ]
                     [ ul [ class "search-sidebar" ] searchBuckets
                     , div []
-                        (viewResults model result viewSuccess toRoute outMsg categoryName)
+                        (viewResults nixosChannels model result viewSuccess toRoute outMsg categoryName)
                     ]
 
         RemoteData.Failure error ->
@@ -960,12 +923,13 @@ viewBucket title buckets searchMsgFor selectedBucket sets =
 
 
 viewSearchInput :
-    (Msg a b -> c)
+    List NixOSChannel
+    -> (Msg a b -> c)
     -> String
     -> Maybe String
     -> Maybe String
     -> Html c
-viewSearchInput outMsg categoryName selectedChannel searchQuery =
+viewSearchInput nixosChannels outMsg categoryName selectedChannel searchQuery =
     form
         [ onSubmit (outMsg QueryInputSubmit)
         , class "search-input"
@@ -986,17 +950,22 @@ viewSearchInput outMsg categoryName selectedChannel searchQuery =
                 [ text "Search" ]
             ]
             :: (selectedChannel
-                    |> Maybe.map (\x -> [ div [] (viewChannels outMsg x) ])
+                    |> Maybe.map (\x -> [ div [] (viewChannels nixosChannels outMsg x) ])
                     |> Maybe.withDefault []
                )
         )
 
 
 viewChannels :
-    (Msg a b -> c)
+    List NixOSChannel
+    -> (Msg a b -> c)
     -> String
     -> List (Html c)
-viewChannels outMsg selectedChannel =
+viewChannels nixosChannels outMsg selectedChannel =
+    let
+        channels =
+            List.map .id nixosChannels
+    in
     List.append
         [ div []
             [ h4 [] [ text "Channel: " ]
@@ -1004,10 +973,7 @@ viewChannels outMsg selectedChannel =
                 [ class "btn-group"
                 , attribute "data-toggle" "buttons-radio"
                 ]
-                (List.filterMap
+                (List.map
-                    (\channelId ->
-                        channelDetailsFromId channelId
-                            |> Maybe.map
                     (\channel ->
                         button
                             [ type_ "button"
@@ -1017,10 +983,9 @@ viewChannels outMsg selectedChannel =
                                 ]
                             , onClick <| outMsg (ChannelChange channel.id)
                             ]
-                                        [ text channel.title ]
+                            [ text <| channelTitle channel ]
                     )
-                    )
+                    nixosChannels
-                    channels
                 )
             ]
         ]
@@ -1037,10 +1002,12 @@ viewChannels outMsg selectedChannel =
 
 
 viewResults :
-    Model a b
+    List NixOSChannel
+    -> Model a b
     -> SearchResult a b
     ->
-        (String
+        (List NixOSChannel
+         -> String
          -> Details
          -> Maybe String
          -> List (ResultItem a)
@@ -1050,7 +1017,7 @@ viewResults :
     -> (Msg a b -> c)
     -> String
     -> List (Html c)
-viewResults model result viewSuccess _ outMsg categoryName =
+viewResults nixosChannels model result viewSuccess _ outMsg categoryName =
     let
         from =
             String.fromInt (model.from + 1)
@@ -1093,7 +1060,7 @@ viewResults model result viewSuccess _ outMsg categoryName =
                 )
             )
         ]
-    , viewSuccess model.channel model.showInstallDetails model.show result.hits.hits
+    , viewSuccess nixosChannels model.channel model.showInstallDetails model.show result.hits.hits
     , Html.map outMsg <| viewPager model result.hits.total.value
     ]
 
@@ -1379,6 +1346,7 @@ makeRequestBody query from sizeRaw sort type_ sortField otherSortFields bucketsF
 
 makeRequest :
     Http.Body
+    -> List NixOSChannel
     -> String
     -> Json.Decode.Decoder a
     -> Json.Decode.Decoder b
@@ -1386,10 +1354,15 @@ makeRequest :
     -> (RemoteData.WebData (SearchResult a b) -> Msg a b)
     -> Maybe String
     -> Cmd (Msg a b)
-makeRequest body channel decodeResultItemSource decodeResultAggregations options responseMsg tracker =
+makeRequest body nixosChannels channel decodeResultItemSource decodeResultAggregations options responseMsg tracker =
     let
+        branch : String
         branch =
-            Maybe.map (\details -> details.branch) (channelDetailsFromId channel) |> Maybe.withDefault channel
+            nixosChannels
+                |> List.filter (\x -> x.id == channel)
+                |> List.head
+                |> Maybe.map (\x -> x.branch)
+                |> Maybe.withDefault channel
 
         index =
             "latest-" ++ String.fromInt options.mappingSchemaVersion ++ "-" ++ branch

frontend/src/index.js

@@ -6,9 +6,10 @@ const {Elm} = require('./Main');
 
 Elm.Main.init({
   flags: {
-    elasticsearchMappingSchemaVersion: parseInt(process.env.ELASTICSEARCH_MAPPING_SCHEMA_VERSION) || 0,
+    elasticsearchMappingSchemaVersion: parseInt(process.env.ELASTICSEARCH_MAPPING_SCHEMA_VERSION),
     elasticsearchUrl: process.env.ELASTICSEARCH_URL || 'https://nixos-search-5886075189.us-east-1.bonsaisearch.net:443',
     elasticsearchUsername : process.env.ELASTICSEARCH_USERNAME || 'z3ZFJ6y2mR',
-    elasticsearchPassword : process.env.ELASTICSEARCH_PASSWORD || 'ds8CEvALPf9pui7XG'
+    elasticsearchPassword : process.env.ELASTICSEARCH_PASSWORD || 'ds8CEvALPf9pui7XG',
+    nixosChannels : JSON.parse(process.env.NIXOS_CHANNELS)
   }
 });

frontend/webpack.config.js

@@ -27,7 +27,8 @@ var common = {
     },
     plugins: [
         new webpack.EnvironmentPlugin([
-          "ELASTICSEARCH_MAPPING_SCHEMA_VERSION"
+          "ELASTICSEARCH_MAPPING_SCHEMA_VERSION",
+          "NIXOS_CHANNELS"
         ]),
         new HTMLWebpackPlugin({
             // Use this template to get basic responsive meta tags