From dc6434af40a7ae88b35a7d693c6ff686a538203b Mon Sep 17 00:00:00 2001
From: Guilhem Lettron <glettron@akamai.com>
Date: Fri, 6 Sep 2024 15:35:32 +0200
Subject: [PATCH] feat(akamai): unzip user content

---
 docs/release-notes.md                 |  1 +
 internal/providers/akamai/akamai.go   |  9 +++-
 internal/providers/util/unzip.go      | 36 +++++++++++++++
 internal/providers/util/unzip_test.go | 63 +++++++++++++++++++++++++++
 4 files changed, 108 insertions(+), 1 deletion(-)
 create mode 100644 internal/providers/util/unzip.go
 create mode 100644 internal/providers/util/unzip_test.go

diff --git a/docs/release-notes.md b/docs/release-notes.md
index c734609fe..6fc298861 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -12,6 +12,7 @@ nav_order: 9
 
 - Support partitioning disk with mounted partitions
 - Support Proxmox VE
+- Support gzipped Akamai user_data
 
 ### Changes
 
diff --git a/internal/providers/akamai/akamai.go b/internal/providers/akamai/akamai.go
index 648be3bee..0cd3b63eb 100644
--- a/internal/providers/akamai/akamai.go
+++ b/internal/providers/akamai/akamai.go
@@ -91,7 +91,14 @@ func fetchConfig(f *resource.Fetcher) (types.Config, report.Report, error) {
 		return types.Config{}, report.Report{}, fmt.Errorf("decode base64: %w", err)
 	}
 
-	return util.ParseConfig(f.Logger, data[:n])
+	// The Linode Metadata Service can compress userdata.
+	// We have to gunzip if needed.
+	unzipData, err := util.TryUnzip(data[:n])
+	if err != nil {
+		return types.Config{}, report.Report{}, fmt.Errorf("unzip: %w", err)
+	}
+
+	return util.ParseConfig(f.Logger, unzipData)
 }
 
 // defaultTokenTTL is the time-to-live (TTL; in seconds) for an authorization
diff --git a/internal/providers/util/unzip.go b/internal/providers/util/unzip.go
new file mode 100644
index 000000000..a8193a113
--- /dev/null
+++ b/internal/providers/util/unzip.go
@@ -0,0 +1,36 @@
+// Copyright 2024 CoreOS, Inc.
+//
+// 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.
+
+package util
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"net/http"
+)
+
+func TryUnzip(raw []byte) ([]byte, error) {
+	if http.DetectContentType(raw) != "application/x-gzip" {
+		return raw, nil
+	}
+
+	reader, err := gzip.NewReader(bytes.NewReader(raw))
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	return io.ReadAll(reader)
+}
diff --git a/internal/providers/util/unzip_test.go b/internal/providers/util/unzip_test.go
new file mode 100644
index 000000000..91b4a4e71
--- /dev/null
+++ b/internal/providers/util/unzip_test.go
@@ -0,0 +1,63 @@
+// Copyright 2024 CoreOS, Inc.
+//
+// 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.
+
+package util_test
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/coreos/ignition/v2/internal/providers/util"
+)
+
+func TestTryUnzip(t *testing.T) {
+	type args struct {
+		raw []byte
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    []byte
+		wantErr bool
+	}{
+		{
+			name: "uncompressed",
+			args: args{
+				raw: []byte("hello world"),
+			},
+			want:    []byte("hello world"),
+			wantErr: false,
+		},
+		{
+			name: "compressed",
+			args: args{
+				raw: []byte{0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xcb, 0x48, 0xcd, 0xc9, 0xc9, 0x57, 0x28, 0xcf, 0x2f, 0xca, 0x49, 0x01, 0x00, 0x85, 0x11, 0x4a, 0x0d, 0x0b, 0x00, 0x00, 0x00},
+			},
+			want:    []byte("hello world"),
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := util.TryUnzip(tt.args.raw)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("TryUnzip() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("TryUnzip() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}