本文為英文版的機器翻譯版本，如內容有任何歧義或不一致之處，概以英文版為準。
# `DescribeKey` 搭配 AWS SDK 或 CLI 使用
下列程式碼範例示範如何使用 `DescribeKey`。
動作範例是大型程式的程式碼摘錄，必須在內容中執行。您可以在下列程式碼範例的內容中看到此動作：
+ [了解基本概念](example_kms_Scenario_Basics_section.md)
------
#### [ .NET ]
**適用於 .NET 的 SDK**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/dotnetv3/KMS#code-examples)中設定和執行。
```
using System;
using System.Threading.Tasks;
using Amazon.KeyManagementService;
using Amazon.KeyManagementService.Model;
///
/// Retrieve information about an AWS Key Management Service (AWS KMS) key.
/// You can supply either the key Id or the key Amazon Resource Name (ARN)
/// to the DescribeKeyRequest KeyId property.
///
public class DescribeKey
{
public static async Task Main()
{
var keyId = "7c9eccc2-38cb-4c4f-9db3-766ee8dd3ad4";
var request = new DescribeKeyRequest
{
KeyId = keyId,
};
var client = new AmazonKeyManagementServiceClient();
var response = await client.DescribeKeyAsync(request);
var metadata = response.KeyMetadata;
Console.WriteLine($"{metadata.KeyId} created on: {metadata.CreationDate}");
Console.WriteLine($"State: {metadata.KeyState}");
Console.WriteLine($"{metadata.Description}");
}
}
```
+ 如需 API 詳細資訊，請參閱《*適用於 .NET 的 AWS SDK API 參考*》中的 [DescribeKey](https://docs.aws.amazon.com/goto/DotNetSDKV3/kms-2014-11-01/DescribeKey)。
------
#### [ CLI ]
**AWS CLI**
**範例 1：尋找 KMS 金鑰的詳細資訊**
下列`describe-key`範例會取得範例帳戶和區域中 Amazon S3 AWS 受管金鑰的詳細資訊。您可以使用此命令來尋找 AWS 受管金鑰和客戶受管金鑰的詳細資訊。
若要指定 KMS 金鑰，請使用 `key-id` 參數。此範例使用別名的名稱值，但您可以在此命令中使用金鑰 ID、金鑰 ARN、別名的名稱或別名 ARN。
```
aws kms describe-key \
--key-id alias/aws/s3
```
輸出：
```
{
"KeyMetadata": {
"AWSAccountId": "846764612917",
"KeyId": "b8a9477d-836c-491f-857e-07937918959b",
"Arn": "arn:aws:kms:us-west-2:846764612917:key/b8a9477d-836c-491f-857e-07937918959b",
"CurrentKeyMaterialId": "0b7fd7ddbac6eef27907413567cad8c810e2883dc8a7534067a82ee1142fc1e6",
"CreationDate": 2017-06-30T21:44:32.140000+00:00,
"Enabled": true,
"Description": "Default KMS key that protects my S3 objects when no other key is defined",
"KeyUsage": "ENCRYPT_DECRYPT",
"KeyState": "Enabled",
"Origin": "AWS_KMS",
"KeyManager": "AWS",
"CustomerMasterKeySpec": "SYMMETRIC_DEFAULT",
"EncryptionAlgorithms": [
"SYMMETRIC_DEFAULT"
]
}
}
```
如需詳細資訊，請參閱《AWS Key Management Service 開發人員指南》**中的[檢視金鑰](https://docs.aws.amazon.com/kms/latest/developerguide/viewing-keys.html)。
**範例 2：取得 RSA 非對稱 KMS 金鑰的詳細資訊**
下列 `describe-key` 範例會取得用於簽署和驗證的非對稱 RSA KMS 金鑰的詳細資訊。
```
aws kms describe-key \
--key-id 1234abcd-12ab-34cd-56ef-1234567890ab
```
輸出：
```
{
"KeyMetadata": {
"AWSAccountId": "111122223333",
"KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab",
"Arn": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab",
"CreationDate": "2019-12-02T19:47:14.861000+00:00",
"CustomerMasterKeySpec": "RSA_2048",
"Enabled": false,
"Description": "",
"KeyState": "Disabled",
"Origin": "AWS_KMS",
"MultiRegion": false,
"KeyManager": "CUSTOMER",
"KeySpec": "RSA_2048",
"KeyUsage": "SIGN_VERIFY",
"SigningAlgorithms": [
"RSASSA_PKCS1_V1_5_SHA_256",
"RSASSA_PKCS1_V1_5_SHA_384",
"RSASSA_PKCS1_V1_5_SHA_512",
"RSASSA_PSS_SHA_256",
"RSASSA_PSS_SHA_384",
"RSASSA_PSS_SHA_512"
]
}
}
```
**範例 3：取得多區域複本金鑰的詳細資訊**
下列 `describe-key` 範例會取得多區域複本金鑰的中繼資料。此多區域金鑰是對稱加密金鑰。任何多區域金鑰的 `describe-key` 命令輸出，都會傳回主金鑰及其所有複本的相關資訊。
```
aws kms describe-key \
--key-id arn:aws:kms:ap-northeast-1:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab
```
輸出：
```
{
"KeyMetadata": {
"MultiRegion": true,
"AWSAccountId": "111122223333",
"Arn": "arn:aws:kms:ap-northeast-1:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab",
"CreationDate": "2021-06-28T21:09:16.114000+00:00",
"CurrentKeyMaterialId": "0b7fd7ddbac6eef27907413567cad8c810e2883dc8a7534067a82ee1142fc1e6",
"Description": "",
"Enabled": true,
"KeyId": "mrk-1234abcd12ab34cd56ef1234567890ab",
"KeyManager": "CUSTOMER",
"KeyState": "Enabled",
"KeyUsage": "ENCRYPT_DECRYPT",
"Origin": "AWS_KMS",
"CustomerMasterKeySpec": "SYMMETRIC_DEFAULT",
"EncryptionAlgorithms": [
"SYMMETRIC_DEFAULT"
],
"MultiRegionConfiguration": {
"MultiRegionKeyType": "PRIMARY",
"PrimaryKey": {
"Arn": "arn:aws:kms:us-west-2:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab",
"Region": "us-west-2"
},
"ReplicaKeys": [
{
"Arn": "arn:aws:kms:eu-west-1:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab",
"Region": "eu-west-1"
},
{
"Arn": "arn:aws:kms:ap-northeast-1:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab",
"Region": "ap-northeast-1"
},
{
"Arn": "arn:aws:kms:sa-east-1:111122223333:key/mrk-1234abcd12ab34cd56ef1234567890ab",
"Region": "sa-east-1"
}
]
}
}
}
```
**範例 4：取得 HMAC KMS 金鑰的詳細資訊**
下列 `describe-key` 範例會取得 HMAC KMS 金鑰的詳細資訊。
```
aws kms describe-key \
--key-id 1234abcd-12ab-34cd-56ef-1234567890ab
```
輸出：
```
{
"KeyMetadata": {
"AWSAccountId": "123456789012",
"KeyId": "1234abcd-12ab-34cd-56ef-1234567890ab",
"Arn": "arn:aws:kms:us-west-2:123456789012:key/1234abcd-12ab-34cd-56ef-1234567890ab",
"CreationDate": "2022-04-03T22:23:10.194000+00:00",
"Enabled": true,
"Description": "Test key",
"KeyUsage": "GENERATE_VERIFY_MAC",
"KeyState": "Enabled",
"Origin": "AWS_KMS",
"KeyManager": "CUSTOMER",
"CustomerMasterKeySpec": "HMAC_256",
"MacAlgorithms": [
"HMAC_SHA_256"
],
"MultiRegion": false
}
}
```
+ 如需 API 詳細資訊，請參閱《AWS CLI 命令參考》**中的 [DescribeKey](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/kms/describe-key.html)。
------
#### [ Java ]
**SDK for Java 2.x**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javav2/example_code/kms#code-examples)中設定和執行。
```
/**
* Asynchronously checks if a specified key is enabled.
*
* @param keyId the ID of the key to check
* @return a {@link CompletableFuture} that, when completed, indicates whether the key is enabled or not
*
* @throws RuntimeException if an exception occurs while checking the key state
*/
public CompletableFuture isKeyEnabledAsync(String keyId) {
DescribeKeyRequest keyRequest = DescribeKeyRequest.builder()
.keyId(keyId)
.build();
CompletableFuture responseFuture = getAsyncClient().describeKey(keyRequest);
return responseFuture.whenComplete((resp, ex) -> {
if (resp != null) {
KeyState keyState = resp.keyMetadata().keyState();
if (keyState == KeyState.ENABLED) {
logger.info("The key is enabled.");
} else {
logger.info("The key is not enabled. Key state: {}", keyState);
}
} else {
throw new RuntimeException(ex);
}
}).thenApply(resp -> resp.keyMetadata().keyState() == KeyState.ENABLED);
}
```
+ 如需 API 詳細資訊，請參閱《AWS SDK for Java 2.x API 參考》**中的 [DescribeKey](https://docs.aws.amazon.com/goto/SdkForJavaV2/kms-2014-11-01/DescribeKey)。
------
#### [ Kotlin ]
**適用於 Kotlin 的 SDK**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/kotlin/services/kms#code-examples)中設定和執行。
```
suspend fun describeSpecifcKey(keyIdVal: String?) {
val request =
DescribeKeyRequest {
keyId = keyIdVal
}
KmsClient.fromEnvironment { region = "us-west-2" }.use { kmsClient ->
val response = kmsClient.describeKey(request)
println("The key description is ${response.keyMetadata?.description}")
println("The key ARN is ${response.keyMetadata?.arn}")
}
}
```
+ 如需 API 詳細資訊，請參閱《適用於 Kotlin 的AWS SDK API 參考》**中的 [DescribeKey](https://sdk.amazonaws.com/kotlin/api/latest/index.html)。
------
#### [ PHP ]
**適用於 PHP 的 SDK**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/php/example_code/kms#code-examples)中設定和執行。
```
/***
* @param string $keyId
* @return array
*/
public function describeKey(string $keyId)
{
try {
$result = $this->client->describeKey([
"KeyId" => $keyId,
]);
return $result['KeyMetadata'];
}catch(KmsException $caught){
if($caught->getAwsErrorMessage() == "NotFoundException"){
echo "The request was rejected because the specified entity or resource could not be found.\n";
}
throw $caught;
}
}
```
+ 如需 API 詳細資訊，請參閱《適用於 PHP 的 AWS SDK API 參考》**中的 [DescribeKey](https://docs.aws.amazon.com/goto/SdkForPHPV3/kms-2014-11-01/DescribeKey)。
------
#### [ Python ]
**適用於 Python 的 SDK (Boto3)**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/kms#code-examples)中設定和執行。
```
class KeyManager:
def __init__(self, kms_client):
self.kms_client = kms_client
self.created_keys = []
@classmethod
def from_client(cls) -> "KeyManager":
"""
Creates a KeyManager instance with a default KMS client.
:return: An instance of KeyManager initialized with the default KMS client.
"""
kms_client = boto3.client("kms")
return cls(kms_client)
def describe_key(self, key_id: str) -> dict[str, any]:
"""
Describes a key.
:param key_id: The ARN or ID of the key to describe.
:return: Information about the key.
"""
try:
key = self.kms_client.describe_key(KeyId=key_id)["KeyMetadata"]
return key
except ClientError as err:
logging.error(
"Couldn't get key '%s'. Here's why: %s",
key_id,
err.response["Error"]["Message"],
)
raise
```
+ 如需 API 詳細資訊，請參閱《AWS SDK for Python (Boto3) API 參考》**中的 [DescribeKey](https://docs.aws.amazon.com/goto/boto3/kms-2014-11-01/DescribeKey)。
------
#### [ SAP ABAP ]
**適用於 SAP ABAP 的開發套件**
GitHub 上提供更多範例。尋找完整範例，並了解如何在 [AWS 程式碼範例儲存庫](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/sap-abap/services/kms#code-examples)中設定和執行。
```
TRY.
" iv_key_id = 'arn:aws:kms:us-east-1:123456789012:key/1234abcd-12ab-34cd-56ef-1234567890ab'
oo_result = lo_kms->describekey( iv_keyid = iv_key_id ).
DATA(lo_key) = oo_result->get_keymetadata( ).
MESSAGE 'Retrieved key information successfully.' TYPE 'I'.
CATCH /aws1/cx_kmsnotfoundexception.
MESSAGE 'Key not found.' TYPE 'E'.
CATCH /aws1/cx_kmskmsinternalex.
MESSAGE 'An internal error occurred.' TYPE 'E'.
ENDTRY.
```
+ 如需 API 詳細資訊，請參閱《適用於 *AWS SAP ABAP 的 SDK API 參考*》中的 [DescribeKey](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html)。
------
如需 AWS SDK 開發人員指南和程式碼範例的完整清單，請參閱 [搭配 AWS SDK 使用此服務](sdk-general-information-section.md)。此主題也包含有關入門的資訊和舊版 SDK 的詳細資訊。