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spec_dir = File.expand_path(File.join(File.dirname(__FILE__)))
$LOAD_PATH.unshift(spec_dir)
$LOAD_PATH.uniq!

require 'apply_auth_examples'
require 'fakefs/safe'
require 'fileutils'
require 'googleauth/service_account'
require 'jwt'
require 'multi_json'
require 'openssl'
require 'spec_helper'
require 'tmpdir'

include Google::Auth::CredentialsLoader

shared_examples 'jwt header auth' do
  context 'when jwt_aud_uri is present' do
    let(:test_uri) { 'https://www.googleapis.com/myservice' }
    let(:auth_prefix) { 'Bearer ' }
    let(:auth_key) { ServiceAccountJwtHeaderCredentials::AUTH_METADATA_KEY }
    let(:jwt_uri_key) { ServiceAccountJwtHeaderCredentials::JWT_AUD_URI_KEY }

    def expect_is_encoded_jwt(hdr)
      expect(hdr).to_not be_nil
      expect(hdr.start_with?(auth_prefix)).to be true
      authorization = hdr[auth_prefix.length..-1]
      payload, = JWT.decode(authorization, @key.public_key, true, algorithm: 'RS256')
      expect(payload['aud']).to eq(test_uri)
      expect(payload['iss']).to eq(client_email)
    end

    describe '#apply!' do
      it 'should update the target hash with a jwt token' do
        md = { foo: 'bar' }
        md[jwt_uri_key] = test_uri
        @client.apply!(md)
        auth_header = md[auth_key]
        expect_is_encoded_jwt(auth_header)
        expect(md[jwt_uri_key]).to be_nil
      end
    end

    describe 'updater_proc' do
      it 'should provide a proc that updates a hash with a jwt token' do
        md = { foo: 'bar' }
        md[jwt_uri_key] = test_uri
        the_proc = @client.updater_proc
        got = the_proc.call(md)
        auth_header = got[auth_key]
        expect_is_encoded_jwt(auth_header)
        expect(got[jwt_uri_key]).to be_nil
        expect(md[jwt_uri_key]).to_not be_nil
      end
    end

    describe '#apply' do
      it 'should not update the original hash with a jwt token' do
        md = { foo: 'bar' }
        md[jwt_uri_key] = test_uri
        the_proc = @client.updater_proc
        got = the_proc.call(md)
        auth_header = md[auth_key]
        expect(auth_header).to be_nil
        expect(got[jwt_uri_key]).to be_nil
        expect(md[jwt_uri_key]).to_not be_nil
      end

      it 'should add a jwt token to the returned hash' do
        md = { foo: 'bar' }
        md[jwt_uri_key] = test_uri
        got = @client.apply(md)
        auth_header = got[auth_key]
        expect_is_encoded_jwt(auth_header)
      end
    end
  end
end

describe Google::Auth::ServiceAccountCredentials do
  ServiceAccountCredentials = Google::Auth::ServiceAccountCredentials
  let(:client_email) { 'app@developer.gserviceaccount.com' }
  let(:cred_json) do
    {
      private_key_id: 'a_private_key_id',
      private_key: @key.to_pem,
      client_email: client_email,
      client_id: 'app.apps.googleusercontent.com',
      type: 'service_account'
    }
  end

  before(:example) do
    @key = OpenSSL::PKey::RSA.new(2048)
    @client = ServiceAccountCredentials.make_creds(
      json_key_io: StringIO.new(cred_json_text),
      scope: 'https://www.googleapis.com/auth/userinfo.profile'
    )
  end

  def make_auth_stubs(opts = {})
    access_token = opts[:access_token] || ''
    body = MultiJson.dump('access_token' => access_token,
                          'token_type' => 'Bearer',
                          'expires_in' => 3600)
    blk = proc do |request|
      params = Addressable::URI.form_unencode(request.body)
      _claim, _header = JWT.decode(params.assoc('assertion').last,
                                   @key.public_key, true,
                                   algorithm: 'RS256')
    end
    stub_request(:post, 'https://www.googleapis.com/oauth2/v4/token')
      .with(body: hash_including(
        'grant_type' => 'urn:ietf:params:oauth:grant-type:jwt-bearer'
      ),
            &blk)
      .to_return(body: body,
                 status: 200,
                 headers: { 'Content-Type' => 'application/json' })
  end

  def cred_json_text
    MultiJson.dump(cred_json)
  end

  it_behaves_like 'apply/apply! are OK'

  context 'when scope is nil' do
    before(:example) do
      @client.scope = nil
    end

    it_behaves_like 'jwt header auth'
  end

  describe '#from_env' do
    before(:example) do
      @var_name = ENV_VAR
      @credential_vars = [
        ENV_VAR, PRIVATE_KEY_VAR, CLIENT_EMAIL_VAR, ACCOUNT_TYPE_VAR
      ]
      @original_env_vals = {}
      @credential_vars.each { |var| @original_env_vals[var] = ENV[var] }
      ENV[ACCOUNT_TYPE_VAR] = cred_json[:type]

      @scope = 'https://www.googleapis.com/auth/userinfo.profile'
      @clz = ServiceAccountCredentials
    end

    after(:example) do
      @credential_vars.each { |var| ENV[var] = @original_env_vals[var] }
    end

    it 'returns nil if the GOOGLE_APPLICATION_CREDENTIALS is unset' do
      ENV.delete(@var_name) unless ENV[@var_name].nil?
      expect(ServiceAccountCredentials.from_env(@scope)).to be_nil
    end

    it 'fails if the GOOGLE_APPLICATION_CREDENTIALS path does not exist' do
      ENV.delete(@var_name) unless ENV[@var_name].nil?
      expect(ServiceAccountCredentials.from_env(@scope)).to be_nil
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, 'does-not-exist')
        ENV[@var_name] = key_path
        expect { @clz.from_env(@scope) }.to raise_error RuntimeError
      end
    end

    it 'succeeds when the GOOGLE_APPLICATION_CREDENTIALS file is valid' do
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, 'my_cert_file')
        FileUtils.mkdir_p(File.dirname(key_path))
        File.write(key_path, cred_json_text)
        ENV[@var_name] = key_path
        expect(@clz.from_env(@scope)).to_not be_nil
      end
    end

    it 'succeeds when GOOGLE_PRIVATE_KEY and GOOGLE_CLIENT_EMAIL env vars are'\
      ' valid' do
      ENV[PRIVATE_KEY_VAR] = cred_json[:private_key]
      ENV[CLIENT_EMAIL_VAR] = cred_json[:client_email]
      expect(@clz.from_env(@scope)).to_not be_nil
    end
  end

  describe '#from_well_known_path' do
    before(:example) do
      @home = ENV['HOME']
      @scope = 'https://www.googleapis.com/auth/userinfo.profile'
      @known_path = WELL_KNOWN_PATH
      @clz = ServiceAccountCredentials
    end

    after(:example) do
      ENV['HOME'] = @home unless @home == ENV['HOME']
    end

    it 'is nil if no file exists' do
      ENV['HOME'] = File.dirname(__FILE__)
      expect(ServiceAccountCredentials.from_well_known_path(@scope)).to be_nil
    end

    it 'successfully loads the file when it is present' do
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, '.config', @known_path)
        FileUtils.mkdir_p(File.dirname(key_path))
        File.write(key_path, cred_json_text)
        ENV['HOME'] = dir
        expect(@clz.from_well_known_path(@scope)).to_not be_nil
      end
    end
  end

  describe '#from_system_default_path' do
    before(:example) do
      @scope = 'https://www.googleapis.com/auth/userinfo.profile'
      @path = File.join('/etc/google/auth/', CREDENTIALS_FILE_NAME)
      @clz = ServiceAccountCredentials
    end

    it 'is nil if no file exists' do
      FakeFS do
        expect(ServiceAccountCredentials.from_system_default_path(@scope))
          .to be_nil
      end
    end

    it 'successfully loads the file when it is present' do
      FakeFS do
        FileUtils.mkdir_p(File.dirname(@path))
        File.write(@path, cred_json_text)
        expect(@clz.from_system_default_path(@scope)).to_not be_nil
        File.delete(@path)
      end
    end
  end
end

describe Google::Auth::ServiceAccountJwtHeaderCredentials do
  ServiceAccountJwtHeaderCredentials =
    Google::Auth::ServiceAccountJwtHeaderCredentials

  let(:client_email) { 'app@developer.gserviceaccount.com' }
  let(:clz) { Google::Auth::ServiceAccountJwtHeaderCredentials }
  let(:cred_json) do
    {
      private_key_id: 'a_private_key_id',
      private_key: @key.to_pem,
      client_email: client_email,
      client_id: 'app.apps.googleusercontent.com',
      type: 'service_account'
    }
  end

  before(:example) do
    @key = OpenSSL::PKey::RSA.new(2048)
    @client = clz.make_creds(json_key_io: StringIO.new(cred_json_text))
  end

  def cred_json_text
    MultiJson.dump(cred_json)
  end

  it_behaves_like 'jwt header auth'

  describe '#from_env' do
    before(:example) do
      @var_name = ENV_VAR
      @credential_vars = [
        ENV_VAR, PRIVATE_KEY_VAR, CLIENT_EMAIL_VAR, ACCOUNT_TYPE_VAR
      ]
      @original_env_vals = {}
      @credential_vars.each { |var| @original_env_vals[var] = ENV[var] }
      ENV[ACCOUNT_TYPE_VAR] = cred_json[:type]
    end

    after(:example) do
      @credential_vars.each { |var| ENV[var] = @original_env_vals[var] }
    end

    it 'returns nil if the GOOGLE_APPLICATION_CREDENTIALS is unset' do
      ENV.delete(@var_name) unless ENV[@var_name].nil?
      expect(clz.from_env).to be_nil
    end

    it 'fails if the GOOGLE_APPLICATION_CREDENTIALS path does not exist' do
      ENV.delete(@var_name) unless ENV[@var_name].nil?
      expect(clz.from_env).to be_nil
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, 'does-not-exist')
        ENV[@var_name] = key_path
        expect { clz.from_env }.to raise_error RuntimeError
      end
    end

    it 'succeeds when the GOOGLE_APPLICATION_CREDENTIALS file is valid' do
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, 'my_cert_file')
        FileUtils.mkdir_p(File.dirname(key_path))
        File.write(key_path, cred_json_text)
        ENV[@var_name] = key_path
        expect(clz.from_env).to_not be_nil
      end
    end

    it 'succeeds when GOOGLE_PRIVATE_KEY and GOOGLE_CLIENT_EMAIL env vars are'\
      ' valid' do
      ENV[PRIVATE_KEY_VAR] = cred_json[:private_key]
      ENV[CLIENT_EMAIL_VAR] = cred_json[:client_email]
      expect(clz.from_env(@scope)).to_not be_nil
    end
  end

  describe '#from_well_known_path' do
    before(:example) do
      @home = ENV['HOME']
    end

    after(:example) do
      ENV['HOME'] = @home unless @home == ENV['HOME']
    end

    it 'is nil if no file exists' do
      ENV['HOME'] = File.dirname(__FILE__)
      expect(clz.from_well_known_path).to be_nil
    end

    it 'successfully loads the file when it is present' do
      Dir.mktmpdir do |dir|
        key_path = File.join(dir, '.config', WELL_KNOWN_PATH)
        FileUtils.mkdir_p(File.dirname(key_path))
        File.write(key_path, cred_json_text)
        ENV['HOME'] = dir
        expect(clz.from_well_known_path).to_not be_nil
      end
    end
  end
end
