import { EndpointParameterInstructions } from "@aws-sdk/middleware-endpoint";
import { Command as $Command } from "@aws-sdk/smithy-client";
import { Handler, HttpHandlerOptions as __HttpHandlerOptions, MetadataBearer as __MetadataBearer, MiddlewareStack } from "@aws-sdk/types";
import { EC2ClientResolvedConfig, ServiceInputTypes, ServiceOutputTypes } from "../EC2Client";
import { DescribeInstancesRequest } from "../models/models_3";
import { DescribeInstancesResult } from "../models/models_4";
/**
 * @public
 *
 * The input for {@link DescribeInstancesCommand}.
 */
export interface DescribeInstancesCommandInput extends DescribeInstancesRequest {
}
/**
 * @public
 *
 * The output of {@link DescribeInstancesCommand}.
 */
export interface DescribeInstancesCommandOutput extends DescribeInstancesResult, __MetadataBearer {
}
/**
 * @public
 * <p>Describes the specified instances or all instances.</p>
 *          <p>If you specify instance IDs, the output includes information for only the specified
 *             instances. If you specify filters, the output includes information for only those
 *             instances that meet the filter criteria. If you do not specify instance IDs or filters,
 *             the output includes information for all instances, which can affect performance. We
 *             recommend that you use pagination to ensure that the operation returns quickly and
 *             successfully.</p>
 *          <p>If you specify an instance ID that is not valid, an error is returned. If you specify
 *             an instance that you do not own, it is not included in the output.</p>
 *          <p>Recently terminated instances might appear in the returned results. This interval is
 *             usually less than one hour.</p>
 *          <p>If you describe instances in the rare case where an Availability Zone is experiencing
 *             a service disruption and you specify instance IDs that are in the affected zone, or do
 *             not specify any instance IDs at all, the call fails. If you describe instances and
 *             specify only instance IDs that are in an unaffected zone, the call works
 *             normally.</p>
 * @example
 * Use a bare-bones client and the command you need to make an API call.
 * ```javascript
 * import { EC2Client, DescribeInstancesCommand } from "@aws-sdk/client-ec2"; // ES Modules import
 * // const { EC2Client, DescribeInstancesCommand } = require("@aws-sdk/client-ec2"); // CommonJS import
 * const client = new EC2Client(config);
 * const input = { // DescribeInstancesRequest
 *   Filters: [ // FilterList
 *     { // Filter
 *       Name: "STRING_VALUE",
 *       Values: [ // ValueStringList
 *         "STRING_VALUE",
 *       ],
 *     },
 *   ],
 *   InstanceIds: [ // InstanceIdStringList
 *     "STRING_VALUE",
 *   ],
 *   DryRun: true || false,
 *   MaxResults: Number("int"),
 *   NextToken: "STRING_VALUE",
 * };
 * const command = new DescribeInstancesCommand(input);
 * const response = await client.send(command);
 * ```
 *
 * @param DescribeInstancesCommandInput - {@link DescribeInstancesCommandInput}
 * @returns {@link DescribeInstancesCommandOutput}
 * @see {@link DescribeInstancesCommandInput} for command's `input` shape.
 * @see {@link DescribeInstancesCommandOutput} for command's `response` shape.
 * @see {@link EC2ClientResolvedConfig | config} for EC2Client's `config` shape.
 *
 *
 * @example To describe an Amazon EC2 instance
 * ```javascript
 * // This example describes the specified instance.
 * const input = {
 *   "InstanceIds": [
 *     "i-1234567890abcdef0"
 *   ]
 * };
 * const command = new DescribeInstancesCommand(input);
 * await client.send(command);
 * // example id: to-describe-an-amazon-ec2-instance-1529025982172
 * ```
 *
 * @example To describe the instances with a specific instance type
 * ```javascript
 * // This example describes the instances with the t2.micro instance type.
 * const input = {
 *   "Filters": [
 *     {
 *       "Name": "instance-type",
 *       "Values": [
 *         "t2.micro"
 *       ]
 *     }
 *   ]
 * };
 * const command = new DescribeInstancesCommand(input);
 * await client.send(command);
 * // example id: to-describe-the-instances-with-the-instance-type-t2micro-1529026147602
 * ```
 *
 * @example To describe the instances with a specific tag
 * ```javascript
 * // This example describes the instances with the Purpose=test tag.
 * const input = {
 *   "Filters": [
 *     {
 *       "Name": "tag:Purpose",
 *       "Values": [
 *         "test"
 *       ]
 *     }
 *   ]
 * };
 * const command = new DescribeInstancesCommand(input);
 * await client.send(command);
 * // example id: to-describe-the-instances-with-a-specific-tag-1529026251928
 * ```
 *
 */
export declare class DescribeInstancesCommand extends $Command<DescribeInstancesCommandInput, DescribeInstancesCommandOutput, EC2ClientResolvedConfig> {
    readonly input: DescribeInstancesCommandInput;
    static getEndpointParameterInstructions(): EndpointParameterInstructions;
    /**
     * @public
     */
    constructor(input: DescribeInstancesCommandInput);
    /**
     * @internal
     */
    resolveMiddleware(clientStack: MiddlewareStack<ServiceInputTypes, ServiceOutputTypes>, configuration: EC2ClientResolvedConfig, options?: __HttpHandlerOptions): Handler<DescribeInstancesCommandInput, DescribeInstancesCommandOutput>;
    /**
     * @internal
     */
    private serialize;
    /**
     * @internal
     */
    private deserialize;
}
