Use DescribeKeyPairs with an AWS SDK or CLI

    /// <summary>
    /// Get information about an Amazon EC2 key pair.
    /// </summary>
    /// <param name="keyPairName">The name of the key pair.</param>
    /// <returns>A list of key pair information.</returns>
    public async Task<List<KeyPairInfo>> DescribeKeyPairs(string keyPairName)
    {
        try
        {
            var request = new DescribeKeyPairsRequest();
            if (!string.IsNullOrEmpty(keyPairName))
            {
                request = new DescribeKeyPairsRequest
                {
                    KeyNames = new List<string> { keyPairName }
                };
            }

            var response = await _amazonEC2.DescribeKeyPairsAsync(request);
            return response.KeyPairs.ToList();
        }
        catch (AmazonEC2Exception ec2Exception)
        {
            if (ec2Exception.ErrorCode == "InvalidKeyPair.NotFound")
            {
                _logger.LogError(
                    $"A key pair called {keyPairName} does not exist.");
            }

            throw;
        }
        catch (Exception ex)
        {
            _logger.LogError(
                $"An error occurred while describing the key pair.: {ex.Message}");
            throw;
        }
    }

###############################################################################
# function ec2_describe_key_pairs
#
# This function describes one or more Amazon Elastic Compute Cloud (Amazon EC2) key pairs.
#
# Parameters:
#       -h - Display help.
#
# And:
#       0 - If successful.
#       1 - If it fails.
###############################################################################
function ec2_describe_key_pairs() {
  local option OPTARG # Required to use getopts command in a function.

  # bashsupport disable=BP5008
  function usage() {
    echo "function ec2_describe_key_pairs"
    echo "Describes one or more Amazon Elastic Compute Cloud (Amazon EC2) key pairs."
    echo "  -h - Display help."
    echo ""
  }

  # Retrieve the calling parameters.
  while getopts "h" option; do
    case "${option}" in
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  local response

  response=$(aws ec2 describe-key-pairs \
    --query 'KeyPairs[*].[KeyName, KeyFingerprint]' \
    --output text) || {
    aws_cli_error_log ${?}
    errecho "ERROR: AWS reports describe-key-pairs operation failed.$response"
    return 1
  }

  echo "$response"

  return 0
}

The utility functions used in this example.

###############################################################################
# function errecho
#
# This function outputs everything sent to it to STDERR (standard error output).
###############################################################################
function errecho() {
  printf "%s\n" "$*" 1>&2
}

##############################################################################
# function aws_cli_error_log()
#
# This function is used to log the error messages from the AWS CLI.
#
# The function expects the following argument:
#         $1 - The error code returned by the AWS CLI.
#
#  Returns:
#          0: - Success.
#
##############################################################################
function aws_cli_error_log() {
  local err_code=$1
  errecho "Error code : $err_code"
  if [ "$err_code" == 1 ]; then
    errecho "  One or more S3 transfers failed."
  elif [ "$err_code" == 2 ]; then
    errecho "  Command line failed to parse."
  elif [ "$err_code" == 130 ]; then
    errecho "  Process received SIGINT."
  elif [ "$err_code" == 252 ]; then
    errecho "  Command syntax invalid."
  elif [ "$err_code" == 253 ]; then
    errecho "  The system environment or configuration was invalid."
  elif [ "$err_code" == 254 ]; then
    errecho "  The service returned an error."
  elif [ "$err_code" == 255 ]; then
    errecho "  255 is a catch-all error."
  fi

  return 0
}

//! Describe all Amazon Elastic Compute Cloud (Amazon EC2) instance key pairs.
/*!
  \param clientConfiguration: AWS client configuration.
  \return bool: Function succeeded.
 */
bool AwsDoc::EC2::describeKeyPairs(
        const Aws::Client::ClientConfiguration &clientConfiguration) {
    Aws::EC2::EC2Client ec2Client(clientConfiguration);
    Aws::EC2::Model::DescribeKeyPairsRequest request;

    Aws::EC2::Model::DescribeKeyPairsOutcome outcome = ec2Client.DescribeKeyPairs(request);
    if (outcome.IsSuccess()) {
        std::cout << std::left <<
                  std::setw(32) << "Name" <<
                  std::setw(64) << "Fingerprint" << std::endl;

        const std::vector<Aws::EC2::Model::KeyPairInfo> &key_pairs =
                outcome.GetResult().GetKeyPairs();
        for (const auto &key_pair: key_pairs) {
            std::cout << std::left <<
                      std::setw(32) << key_pair.GetKeyName() <<
                      std::setw(64) << key_pair.GetKeyFingerprint() << std::endl;
        }
    } else {
        std::cerr << "Failed to describe key pairs:" <<
                  outcome.GetError().GetMessage() << std::endl;
    }

    return outcome.IsSuccess();
}

To display a key pair

The following describe-key-pairs example displays information about the specified key pair.

aws ec2 describe-key-pairs \
    --key-names my-key-pair

Output:

{
    "KeyPairs": [
        {
            "KeyPairId": "key-0b94643da6EXAMPLE",
            "KeyFingerprint": "1f:51:ae:28:bf:89:e9:d8:1f:25:5d:37:2d:7d:b8:ca:9f:f5:f1:6f",
            "KeyName": "my-key-pair",
            "KeyType": "rsa",
            "Tags": [],
            "CreateTime": "2022-05-27T21:51:16.000Z"
        }
    ]
}

For more information, see Describe public keys in the Amazon EC2 User Guide.

    /**
     * Asynchronously describes the key pairs associated with the current AWS account.
     *
     * @return a {@link CompletableFuture} containing the {@link DescribeKeyPairsResponse} object, which provides
     * information about the key pairs.
     */
    public CompletableFuture<DescribeKeyPairsResponse> describeKeysAsync() {
        CompletableFuture<DescribeKeyPairsResponse> responseFuture = getAsyncClient().describeKeyPairs();
        responseFuture.whenComplete((response, exception) -> {
            if (exception != null) {
              throw new RuntimeException("Failed to describe key pairs: " + exception.getMessage(), exception);
            }
        });

        return responseFuture;
    }

import { DescribeKeyPairsCommand, EC2Client } from "@aws-sdk/client-ec2";

/**
 * List all key pairs in the current AWS account.
 * @param {{ dryRun: boolean }}
 */
export const main = async ({ dryRun }) => {
  const client = new EC2Client({});
  const command = new DescribeKeyPairsCommand({ DryRun: dryRun });

  try {
    const { KeyPairs } = await client.send(command);
    const keyPairList = KeyPairs.map(
      (kp) => ` • ${kp.KeyPairId}: ${kp.KeyName}`,
    ).join("\n");
    console.log("The following key pairs were found in your account:");
    console.log(keyPairList);
  } catch (caught) {
    if (caught instanceof Error && caught.name === "DryRunOperation") {
      console.log(`${caught.message}`);
    } else {
      throw caught;
    }
  }
};

suspend fun describeEC2Keys() {
    Ec2Client { region = "us-west-2" }.use { ec2 ->
        val response = ec2.describeKeyPairs(DescribeKeyPairsRequest {})
        response.keyPairs?.forEach { keyPair ->
            println("Found key pair with name ${keyPair.keyName} and fingerprint ${ keyPair.keyFingerprint}")
        }
    }
}

Example 1: This example describes the specified key pair.

Get-EC2KeyPair -KeyName my-key-pair

Output:

KeyFingerprint                                              KeyName
--------------                                              -------
1f:51:ae:28:bf:89:e9:d8:1f:25:5d:37:2d:7d:b8:ca:9f:f5:f1:6f my-key-pair

Example 2: This example describes all your key pairs.

Get-EC2KeyPair

class KeyPairWrapper:
    """
    Encapsulates Amazon Elastic Compute Cloud (Amazon EC2) key pair actions.
    This class provides methods to create, list, and delete EC2 key pairs.
    """

    def __init__(
        self,
        ec2_client: boto3.client,
        key_file_dir: Union[tempfile.TemporaryDirectory, str],
        key_pair: Optional[dict] = None,
    ):
        """
        Initializes the KeyPairWrapper with the specified EC2 client, key file directory,
        and an optional key pair.

        :param ec2_client: A Boto3 Amazon EC2 client. This client provides low-level
                           access to AWS EC2 services.
        :param key_file_dir: The folder where the private key information is stored.
                             This should be a secure folder.
        :param key_pair: A dictionary representing the Boto3 KeyPair object.
                         This is a high-level object that wraps key pair actions. Optional.
        """
        self.ec2_client = ec2_client
        self.key_pair = key_pair
        self.key_file_path: Optional[str] = None
        self.key_file_dir = key_file_dir

    @classmethod
    def from_client(cls) -> "KeyPairWrapper":
        """
        Class method to create an instance of KeyPairWrapper using a new EC2 client
        and a temporary directory for storing key files.

        :return: An instance of KeyPairWrapper.
        """
        ec2_client = boto3.client("ec2")
        return cls(ec2_client, tempfile.TemporaryDirectory())


    def list(self, limit: Optional[int] = None) -> None:
        """
        Displays a list of key pairs for the current account.

        WARNING: Results are not paginated.

        :param limit: The maximum number of key pairs to list. If not specified,
                      all key pairs will be listed.
        :raises ClientError: If there is an error in listing the key pairs.
        """
        try:
            response = self.ec2_client.describe_key_pairs()
            key_pairs = response.get("KeyPairs", [])

            if limit:
                key_pairs = key_pairs[:limit]

            for key_pair in key_pairs:
                logger.info(
                    f"Found {key_pair['KeyType']} key '{key_pair['KeyName']}' with fingerprint:"
                )
                logger.info(f"\t{key_pair['KeyFingerprint']}")
        except ClientError as err:
            logger.error(f"Failed to list key pairs: {str(err)}")
            raise

    pub async fn list_key_pair(&self) -> Result<Vec<KeyPairInfo>, EC2Error> {
        let output = self.client.describe_key_pairs().send().await?;
        Ok(output.key_pairs.unwrap_or_default())
    }

    TRY.
        oo_result = lo_ec2->describekeypairs( ) .                        " oo_result is returned for testing purposes. "
        DATA(lt_key_pairs) = oo_result->get_keypairs( ).
        MESSAGE 'Retrieved information about key pairs.' TYPE 'I'.
      CATCH /aws1/cx_rt_service_generic INTO DATA(lo_exception).
        DATA(lv_error) = |"{ lo_exception->av_err_code }" - { lo_exception->av_err_msg }|.
        MESSAGE lv_error TYPE 'E'.
    ENDTRY.