fetchbower is not deterministic

[mr-ouss]

Issue description

After using bower2nix to generate bower-generated.nix, I get the following error when running a nix-build on my expression:

output path ‘/nix/store/lbn3c6i5v62xqi8mk2dfy54vi8mgzkli-angular-block-ui-0.2.2’ has r:sha256 hash ‘09sccghl6mbn32bai6bsa47mw3vibkdnzginc4y62hkx5wks42rk’ when ‘0nzqan0mqj47qic7m74d2rwp178n2wgjw523hw9x2mfnrcicsyvp’ was expected

and the hash is different time I run nix-build!

Steps to reproduce

The problem is easily reproducible.

1- I have the followingbower-generated.nix:

{ fetchbower, buildEnv }:
buildEnv { name = "bower-env"; ignoreCollisions = true; paths = [
    (fetchbower "angular-sweetalert" "1.1.0" "1.1.0" "060wmhivpb257xxa4lg9jznnqn9w7rfk5cvx5513pzfmm5clqw4z")
    (fetchbower "satellizer" "0.14.1" "0.14.1" "00m566lq6ajknxfvlnz65b4wqr4j6cc6vvsym3jbbf8rnss35yha")
    (fetchbower "angular-block-ui" "0.2.2" "0.2.2" "0nzqan0mqj47qic7m74d2rwp178n2wgjw523hw9x2mfnrcicsyvp")
    (fetchbower "angular-moment" "1.0.0-beta.6" "1.0.0-beta.6" "1xzx4z35cmaajwrc7vvyg8n7kkpn03p6yg0q54kldrfkc3r19icz")
    (fetchbower "ngstorage" "0.3.6" "0.3.6" "06y7y0j6igp6w42kh8msbjfnqs1555jxnw4kq6hcl9s8145a0864")
    (fetchbower "angular-smart-table" "2.1.8" "2.1.8" "0yjld9sinx1hxgc28qs8q0dc6xfvf14bdm88zzrwmcdyaggjwf0a")
    (fetchbower "ngSticky" "1.8.11" "1.8.11" "1vwsj1dlnl6462ynn6ji4hff7mzf4p7l6lqzv9b7kb8g1w70lkq4")
    (fetchbower "angular-bootstrap" "1.3.2" "1.3.2" "0b9kr2926643ryfkmhn0hiv78a82q12qgwyadw2la5ajdkv80pvj")
    (fetchbower "angular-ui-router" "0.2.18" "0.2.18" "02xvdn93wfzya6fb6srnk2175hgdkpdwxpnybrsl1yz0j05vphs0")
    (fetchbower "angular-google-chart" "0.1.0" "0.1.0" "16gyw7ww5v2ks43gixg7vfynjgm8xar9h77dkvd1ml2r0z2brc73")
    (fetchbower "jquery" "2.2.4" "2.2.4" "0jir5x9xgkkpql5kwfclg9j4lpysg9dbkq8qbp5j0384kn23d9x8")
    (fetchbower "angular" "1.5.3" "1.5.3" "010fhrgfh8ykwfkyxpndadkpzl72dgy3yr4j83jp3nwpjismnbmg")
    (fetchbower "angular-ui-bootstrap" "1.3.2" "1.3.2" "06rfib7mlgbnlaniyb76w1gqzg5s1hccpzv5hbqwhvvk38fyqkgw")
    (fetchbower "moment" "2.14.1" "2.14.1" "191x42jhgww1bk2h1zmh08h79fz5g5hps5w874rbj8sc7siabkza")
  ];
}

2- And this default.nix:

{ pkgs ? import <nixpkgs> {} 
, mySource ? ./.
, system ? builtins.currentSystem
}:
with import <nixpkgs> { inherit system; };
let
  bowerPackages = import ./bower-generated.nix { inherit (pkgs) fetchbower buildEnv; };
in
{
  bowerComponents = pkgs.stdenv.mkDerivation {
    name = "bower_components";
    inherit bowerPackages;
    src = mySource;
    buildPhase = ''
      cp -RL --reflink=auto ${bowerPackages} bc
      chmod -R u+w bc
      HOME=$PWD bower \
        --config.storage.packages=bc/packages \
        --config.storage.registry=bc/registry \
        --offline install
    '';
    installPhase = "mv bower_components $out";
    buildInputs = [ pkgs.git bowerPackages pkgs.nodePackages.bower ];
  };
}

3- Command that is run:

$ nix-build

Technical details

• System: OSX El Capitan v 10.11.5
• Nix version: (Nix) 1.11.2
• Nixpkgs version: 16.03.1011.6317da4

[rvl]

Sometimes I got different hashes when there was an error downloading the bower package. Could you try fetch-bower -o tmp-bower angular-block-ui 0.2.2 0.2.2 and see if that works ok?

[mr-ouss]

Thank you for the quick reply!
That command did not produce anything

[nix-shell:/Volumes/Projects/foo]$ fetch-bower -o tmp-bower angular-block-ui 0.2.2 0.2.2

[nix-shell:/Volumes/Projects/foo]$ ls -l
total 0

I tried with other packages as well. Nothing seems to happen.

[rvl]

Could I please confirm what are the versions coming from bower2nix --version and fetch-bower --version? The hashes in the above bower-generated.nix work for me.

[mr-ouss]

I'm using the following version of bower2nix

$ bower2nix --version
2.1.0

fetch-bower is not returning anything !

$ fetch-bower --version

[rvl]

Aha, sorry for not noticing earlier. Nixpkgs unstable has a newer version of bower2nix (3.0.1) with bug fixes.

If you switch to the unstable channel, you will also be able to use a simpler method to build bower_components (see Nixpkgs manual 16.09).

If you need to stay with 16.03, it may require overriding the fetchbower function.

[mr-ouss]

Thank you Roney! I'll do that!