async getCredentialsInternal()

in src/providers/oidc_role_arn.ts [184:237]
42 lines of code
11 McCabe index (conditional complexity)

  async getCredentialsInternal(): Promise<Session> {
    const oidcToken = await readFileAsync(this.oidcTokenFilePath, 'utf8');
    const builder = Request.builder().withMethod('POST').withProtocol('https').withHost(this.stsEndpoint).withReadTimeout(this.readTimeout || 10000).withConnectTimeout(this.connectTimeout || 5000);

    const queries = Object.create(null);
    queries['Version'] = '2015-04-01';
    queries['Action'] = 'AssumeRoleWithOIDC';
    queries['Format'] = 'JSON';
    queries['Timestamp'] = utils.timestamp();
    builder.withQueries(queries);

    const bodyForm = Object.create(null);
    bodyForm['OIDCProviderArn'] = this.oidcProviderArn;
    bodyForm['OIDCToken'] = oidcToken;
    bodyForm['RoleArn'] = this.roleArn;
    if (this.policy) {
      bodyForm['Policy'] = this.policy;
    }

    bodyForm['RoleSessionName'] = this.roleSessionName
    bodyForm['DurationSeconds'] = `${this.durationSeconds}`;

    builder.withBodyForm(bodyForm);

    const headers = Object.create(null);
    // set headers
    headers['Content-Type'] = 'application/x-www-form-urlencoded';
    builder.withHeaders(headers);

    const request = builder.build();
    const response = await this.doRequest(request);

    if (response.statusCode !== 200) {
      throw new Error(`get sts token failed with OIDC: ${response.body.toString('utf8')}`)
    }

    let data;
    try {
      data = JSON.parse(response.body.toString('utf8'));
    } catch (ex) {
      throw new Error(`get sts token failed with OIDC, unmarshal fail: ${response.body.toString('utf8')}`);
    }

    if (!data || !data.Credentials) {
      throw new Error(`get sts token failed with OIDC`);
    }

    const { AccessKeyId, AccessKeySecret, SecurityToken, Expiration } = data.Credentials;
    if (!AccessKeyId || !AccessKeySecret || !SecurityToken) {
      throw new Error('get sts token failed with OIDC')
    }

    return new Session(AccessKeyId, AccessKeySecret, SecurityToken, Expiration);
  }