官方文档地址：Other authentication methods

Elasticsearch Token Service tokens

如果希望客户端使用 Elasticsearch access token 进行身份验证，请设置相关的 HTTP 请求头。如果客户端仅代表单个用户进行请求，可以将必要的Authorization头设置为默认头，示例如下：

RestClientBuilder builder = RestClient.builder(
    new HttpHost("localhost", 9200, "http"));
Header[] defaultHeaders =
    new Header[]{new BasicHeader("Authorization",
        "Bearer u6iuAxZ0RG1Kcm5jVFI4eU4tZU9aVFEwT2F3")};
builder.setDefaultHeaders(defaultHeaders);

Elasticsearch API keys

如果您希望客户端使用 Elasticsearch API key 进行身份验证，请设置相关的 HTTP 请求头。如果客户端仅代表单个用户发出请求，可以将必要的Authorization头设置为默认头，示例如下：

String apiKeyId = "uqlEyn8B_gQ_jlvwDIvM";
String apiKeySecret = "HxHWk2m4RN-V_qg9cDpuX";
String apiKeyAuth =
    Base64.getEncoder().encodeToString(
        (apiKeyId + ":" + apiKeySecret)
            .getBytes(StandardCharsets.UTF_8));
RestClientBuilder builder = RestClient.builder(
    new HttpHost("localhost", 9200, "http"));
Header[] defaultHeaders =
    new Header[]{new BasicHeader("Authorization",
        "ApiKey " + apiKeyAuth)};
builder.setDefaultHeaders(defaultHeaders);