Class: OCIRegistry::Remote

Inherits:
Object
  • Object
show all
Defined in:
lib/oci_registry/remote.rb

Class Method Summary collapse

Class Method Details

.display_metadata(config_json) ⇒ Object

Step 5: Extract Labels and Metadata



136
137
138
139
140
141
142
143
144
 
# File 'lib/oci_registry/remote.rb', line 136

def self.display_metadata(config_json)
  labels = config_json['config']['Labels']
  puts "Labels:"
  puts JSON.pretty_generate(labels)

  puts "\nOther Metadata:"
  metadata = config_json['config']
  puts JSON.pretty_generate(metadata)
end

.download_and_extract_layers(host, token, repository, layers, file_name) ⇒ Object

Function to download and extract layers



147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
 
# File 'lib/oci_registry/remote.rb', line 147

def self.download_and_extract_layers(host, token, repository, layers, file_name)
  layers.each_with_index do |layer, index|
    digest = layer['digest']
    puts "Processing layer #{index + 1}/#{layers.size}: #{digest}"

    # Download the layer blob
    uri = URI("https://#{host}/v2/#{repository}/blobs/#{digest}")
    headers = { 'Authorization' => "Bearer #{token}" }

    response = http_get(uri, headers)

    if response.is_a?(Net::HTTPSuccess)
      # Decompress and extract the tar.gz layer
      found = extract_layer(response.body, file_name)
      return true if found
    else
      puts "Failed to download layer #{digest}: #{response.code} #{response.message}"
    end
  end
  false
end

.extract_layer(layer_data, file_name) ⇒ Object

Function to extract a layer and search for the specified file



170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
 
# File 'lib/oci_registry/remote.rb', line 170

def self.extract_layer(layer_data, file_name)
  # Decompress the gzip layer data
  gz = Zlib::GzipReader.new(StringIO.new(layer_data))
  tar_io = StringIO.new(gz.read)

  # Extract tar contents
  Minitar::Input.open(tar_io) do |tar|
    tar.each do |entry|
      # Normalize file paths to handle different directory structures
      entry_path = entry.full_name.sub(/^\.\//, '').sub(/^\/+/, '')

      if File.basename(entry_path) == file_name
        puts "\nFound '#{file_name}' in layer:"
        contents = entry.read
        puts contents
        return true
      end
    end
  end
  false
end

.get_blob(host, token, repository, blob_digest) ⇒ Object

Step 4: Retrieve the Image Configuration



88
89
90
91
92
93
94
95
96
97
98
99
 
# File 'lib/oci_registry/remote.rb', line 88

def self.get_blob(host, token, repository, blob_digest)
  uri = URI("https://#{host}/v2/#{repository}/blobs/#{blob_digest}")
  headers = { 'Authorization' => "Bearer #{token}" }

  response = http_get(uri, headers)

  if response.is_a?(Net::HTTPSuccess)
    JSON.parse(response.body)
  else
    raise "Failed to retrieve image configuration for #{uri.inspect}: #{response.code} #{response.message}"
  end
end

.get_docker_token(repository, username = nil, password = nil) ⇒ Object

Step 1: Obtain an Access Token



46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
 
# File 'lib/oci_registry/remote.rb', line 46

def self.get_docker_token(repository, username = nil, password = nil)
  uri = URI("https://auth.docker.io/token?service=registry.docker.io&scope=repository:#{repository}:pull")

  headers = {}
  if username && password
    encoded_credentials = Base64.strict_encode64("#{username}:#{password}")
    headers['Authorization'] = "Basic #{encoded_credentials}"
  end

  response = http_get(uri, headers)

  if response.is_a?(Net::HTTPSuccess)
    json = JSON.parse(response.body)
    json['token']
  else
    raise "Failed to obtain token: #{response.code} #{response.message}"
  end
end

.get_manifest(host, token, repository, tag) ⇒ Object

Step 2: Fetch the Image Manifest



66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
 
# File 'lib/oci_registry/remote.rb', line 66

def self.get_manifest(host, token, repository, tag)
  uri = URI("https://#{host}/v2/#{repository}/manifests/#{tag}")
  headers = {
    'Authorization' => "Bearer #{token}",
    'Accept' => [
                  'application/vnd.oci.image.index.v1+json',
                  'application/vnd.docker.distribution.manifest.list.v2+json',
                  'application/vnd.oci.image.manifest.v1+json',
                  'application/vnd.docker.distribution.manifest.v2+json'
    ].join(', ')
  }

  response = http_get(uri, headers)

  if response.is_a?(Net::HTTPSuccess)
    JSON.parse(response.body)
  else
    raise "Failed to fetch manifest: #{response.code} #{response.message}"
  end
end

.get_tags(host, token, repository) ⇒ Object

Function to fetch the list of tags for the repository



102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
 
# File 'lib/oci_registry/remote.rb', line 102

def self.get_tags(host, token, repository)
  tags = []
  batch_size = 100
  next_url = "/v2/#{repository}/tags/list?n=#{batch_size}"
  headers = {
    'Authorization' => "Bearer #{token}",
    'Accept' => 'application/json'
  }

  loop do
    uri = URI("https://#{host}#{next_url}")
    response = http_get(uri, headers)

    if response.is_a?(Net::HTTPSuccess)
      json = JSON.parse(response.body)
      tags.concat(json['tags'] || [])

      # Check for pagination
      link_header = response['Link']
      if link_header && link_header.include?('rel="next"')
        next_url = link_header.match(/<(.+)>;/)[1]
      else
        break
      end
    else
      puts "Failed to fetch tags for #{repository}: https://#{host}#{next_url} #{response.code} #{response.message}"
      break
    end
  end

  tags
end

.http_get(uri, headers = {}, limit = 10) ⇒ Object

Helper method to handle HTTP GET requests with redirect support



16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
 
# File 'lib/oci_registry/remote.rb', line 16

def self.http_get(uri, headers = {}, limit = 10)
  raise 'Too many HTTP redirects' if limit == 0

  request = Net::HTTP::Get.new(uri)
  headers.each { |k, v| request[k] = v }

  response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: uri.scheme == 'https') do |http|
    http.request(request)
  end

  case response
  when Net::HTTPRedirection
    location = response['location']
    # warn "Redirected to #{location}"
    # Handle the case where location is a relative URL by reconstructing the full URL
    new_uri = ::URI.join(uri, location)
    http_get(new_uri, headers, limit - 1)
  # 429
  when Net::HTTPTooManyRequests
    puts "Rate limited: #{response.code} #{response.message}"
    # Retry after the specified time
    retry_after = response['Retry-After'].to_i || 10
    sleep(retry_after)
    http_get(uri, headers, limit - 1)
  else
    response
  end
end