add gitea refs

Signed-off-by: ahuston-0 <aliceghuston@gmail.com>
Reviewed-on: https://<censored>/ahuston-0/hydra/pulls/1

doc/manual/src/plugins/README.md

@@ -100,6 +100,15 @@ Create jobs based on open Gitea pull requests
 
 - `gitea_authorization.<repo-owner>`
 
+## Gitea refs
+
+Hydra plugin for retrieving the list of references (branches or tags) from
+Gitea following a certain naming scheme.
+
+### Configuration options
+
+- `gitea_authorization.<repo-owner>`
+
 ## GitHub pulls
 
 Create jobs based on open GitHub pull requests

nixos-tests.nix

@@ -158,6 +158,12 @@ in
             git -C /tmp/repo commit --allow-empty -m 'Additional change'
             git -C /tmp/repo push origin pr
             git -C /tmp/repo log >&2
+
+            # Create release branch
+            git -C /tmp/repo checkout -b release/release-1.0
+            git -C /tmp/repo commit --allow-empty -m 'Additional change'
+            git -C /tmp/repo push origin release/release-1.0
+            git -C /tmp/repo log >&2
           '';
 
           scripts.hydra-setup = pkgs.writeShellScript "hydra.sh" ''
@@ -212,6 +218,11 @@ in
                   "type": "giteapulls",
                   "value": "localhost:3001 root repo http",
                   "emailresponsible": false
+                },
+                "releases": {
+                  "type": "gitea_refs",
+                  "value": "localhost:3001 root repo heads http - release",
+                  "emailresponseible": false
                 }
               }
             }
@@ -240,7 +251,7 @@ in
           };
 
           smallDrv = pkgs.writeText "jobset.nix" ''
-            { pulls, ... }:
+            { pulls, releases, ... }:
 
             let
               genDrv = name: builtins.derivation {
@@ -262,9 +273,19 @@ in
                   }
                 ) prJobNames
               );
+              rels = builtins.fromJSON (builtins.readFile releases);
+              relJobNames = builtins.attrNames rels;
+              relJobset = builtins.listToAttrs (
+                map (
+                  name: {
+                    inherit name;
+                    value = genDrv name;
+                  }
+                ) relJobNames
+              );
             in {
               trivial = genDrv "trivial";
-            } // prJobset
+            } // prJobset // relJobset
           '';
         in
         ''

src/lib/Hydra/Plugin/GiteaRefs.pm

@@ -0,0 +1,129 @@
+package Hydra::Plugin::GiteaRefs;
+
+use strict;
+use warnings;
+use parent 'Hydra::Plugin';
+use HTTP::Request;
+use LWP::UserAgent;
+use JSON::MaybeXS;
+use Hydra::Helper::CatalystUtils;
+use File::Temp;
+use POSIX qw(strftime);
+
+=head1 NAME
+
+GiteaRefs - Hydra plugin for retrieving the list of references (branches or
+tags) from Gitea following a certain naming scheme
+
+=head1 DESCRIPTION
+
+This plugin reads the list of branches or tags using Gitea's REST API. The name
+of the reference must follow a particular prefix. This list is stored in the
+nix-store and used as an input to declarative jobsets.
+
+=head1 CONFIGURATION
+
+The plugin doesn't require any dedicated configuration block, but it has to
+consult C<gitea_authorization> entry for obtaining the API token. In addition,
+
+The declarative project C<spec.json> file must contains an input such as
+
+   "pulls": {
+     "type": "gitea_refs",
+     "value": "[gitea_hostname] [owner] [repo] heads|tags [scheme] - [prefix]",
+     "emailresponsible": false
+   }
+
+In the above snippet, C<[gitea_hostname]> must be set to the hostname of the
+repository's Gitea instance.
+
+C<[owner]> is the repository owner and C<[repo]> is the repository name. Also
+note a literal C<->, which is placed there for the future use.
+
+C<heads|tags> denotes that one of these two is allowed, that is, the third
+position should hold either the C<heads> or the C<tags> keyword. In case of the former, the plugin
+will fetch all branches, while in case of the latter, it will fetch the tags.
+
+C<scheme> should be set to either https or http, depending on what the Gitea
+host supports.
+
+C<prefix> denotes the prefix the reference name must start with, in order to be
+included.
+
+For example, C<"value": "projects.blender.org blender blender heads https - blender-v/"> refers to
+L<https://projects.blender.org/blender/blender> repository, and will fetch all branches that
+begin with C<blender-v/>.
+
+=head1 USE
+
+The result is stored in the nix-store as a JSON I<map>, where the key is the
+name of the reference, while the value is the complete Gitea response. Thus,
+any of the values listed in
+L<https://docs.gitea.com/api#tag/repository/operation/repoListAllGitRefs> can be
+used to build the git input value in C<jobsets.nix>.
+
+=cut
+
+sub supportedInputTypes {
+    my ($self, $inputTypes) = @_;
+    $inputTypes->{'gitea_refs'} = 'Open Gitea Refs';
+}
+
+sub _iterate {
+    my ($url, $auth, $refs, $ua) = @_;
+    my $req = HTTP::Request->new('GET', $url);
+    $req->header('Accept' => 'application/json');
+    $req->header('Authorization' => $auth) if defined $auth;
+    my $res = $ua->request($req);
+    my $content = $res->decoded_content;
+    die "Error pulling from the gitea refs API: $content\n"
+        unless $res->is_success;
+    my $refs_list = decode_json $content;
+    # TODO Stream out the json instead
+    foreach my $ref (@$refs_list) {
+        my $ref_name = $ref->{ref};
+        $ref_name =~ s,^refs/(?:heads|tags)/,,o;
+        $refs->{$ref_name} = $ref;
+    }
+    # TODO Make Link header parsing more robust!!!
+    my @links = split ',', $res->header("Link");
+    my $next = "";
+    foreach my $link (@links) {
+        my ($url, $rel) = split ";", $link;
+        if (trim($rel) eq 'rel="next"') {
+            $next = substr trim($url), 1, -1;
+            last;
+        }
+    }
+    _iterate($next, $auth, $refs, $ua) unless $next eq "";
+}
+
+sub fetchInput {
+    my ($self, $input_type, $name, $value, $project, $jobset) = @_;
+    return undef if $input_type ne "gitea_refs";
+
+    my ($giteaHostname, $owner, $repo, $type, $scheme, $fut, $prefix) = split ' ', $value;
+    die "type field is neither 'heads' nor 'tags', but '$type'"
+        unless $type eq 'heads' or $type eq 'tags';
+    die "scheme field is neither 'https' nor 'http' but '$scheme'"
+        unless $scheme eq 'https' or $scheme eq 'http';
+
+    my $auth = $self->{config}->{gitea_authorization}->{$owner};
+    my $giteaEndpoint = "$scheme://$giteaHostname";
+    my %refs;
+    my $ua = LWP::UserAgent->new();
+    _iterate("$giteaEndpoint/api/v1/repos/$owner/$repo/git/refs/$type/$prefix?per_page=100", $auth, \%refs, $ua);
+    my $tempdir = File::Temp->newdir("gitea-refs" . "XXXXX", TMPDIR => 1);
+    my $filename = "$tempdir/gitea-refs.json";
+    open(my $fh, ">", $filename) or die "Cannot open $filename for writing: $!";
+    print $fh encode_json \%refs;
+    close $fh;
+    system("jq -S . < $filename > $tempdir/gitea-refs-sorted.json");
+    my $storePath = trim(qx{nix-store --add "$tempdir/gitea-refs-sorted.json"}
+        or die "cannot copy path $filename to the Nix store.\n");
+    chomp $storePath;
+    my $timestamp = time;
+    return { storePath => $storePath, revision => strftime "%Y%m%d%H%M%S", gmtime($timestamp) };
+}
+
+1;