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diff --git a/vendor/github.com/mitchellh/packer/vendor/github.com/aws/aws-sdk-go/README.md b/vendor/github.com/mitchellh/packer/vendor/github.com/aws/aws-sdk-go/README.md index 8247981b..d5e048a5 100644 --- a/vendor/github.com/mitchellh/packer/vendor/github.com/aws/aws-sdk-go/README.md +++ b/vendor/github.com/mitchellh/packer/vendor/github.com/aws/aws-sdk-go/README.md @@ -1,11 +1,6 @@ -# AWS SDK for Go +[](http://docs.aws.amazon.com/sdk-for-go/api) [](https://gitter.im/aws/aws-sdk-go?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [](https://travis-ci.org/aws/aws-sdk-go) [](https://github.com/aws/aws-sdk-go/blob/master/LICENSE.txt) -<span style="display: inline-block;"> -[](http://docs.aws.amazon.com/sdk-for-go/api) -[](https://gitter.im/aws/aws-sdk-go?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) -[](https://travis-ci.org/aws/aws-sdk-go) -[](https://github.com/aws/aws-sdk-go/blob/master/LICENSE.txt) -</span> +# AWS SDK for Go aws-sdk-go is the official AWS SDK for the Go programming language. @@ -33,16 +28,17 @@ These two processes will still include the `vendor` folder and it should be dele ## Getting Help Please use these community resources for getting help. We use the GitHub issues for tracking bugs and feature requests. + * Ask a question on [StackOverflow](http://stackoverflow.com/) and tag it with the [`aws-sdk-go`](http://stackoverflow.com/questions/tagged/aws-sdk-go) tag. * Come join the AWS SDK for Go community chat on [gitter](https://gitter.im/aws/aws-sdk-go). * Open a support ticket with [AWS Support](http://docs.aws.amazon.com/awssupport/latest/user/getting-started.html). -* If you think you may of found a bug, please open an [issue](https://github.com/aws/aws-sdk-go/issues/new). +* If you think you may have found a bug, please open an [issue](https://github.com/aws/aws-sdk-go/issues/new). ## Opening Issues -If you encounter a bug with the AWS SDK for Go we would like to hear about it. Search the [existing issues]( https://github.com/aws/aws-sdk-go/issues) and see if others are also experiencing the issue before opening a new issue. Please include the version of AWS SDK for Go, Go language, and OS you’re using. Please also include repro case when appropriate. +If you encounter a bug with the AWS SDK for Go we would like to hear about it. Search the [existing issues](https://github.com/aws/aws-sdk-go/issues) and see if others are also experiencing the issue before opening a new issue. Please include the version of AWS SDK for Go, Go language, and OS you’re using. Please also include repro case when appropriate. -The GitHub issues are intended for bug reports and feature requests. For help and questions with using AWS SDK for GO please make use of the resources listed in the [Getting Help]( https://github.com/aws/aws-sdk-go#getting-help) section. Keeping the list of open issues lean will help us respond in a timely manner. +The GitHub issues are intended for bug reports and feature requests. For help and questions with using AWS SDK for GO please make use of the resources listed in the [Getting Help](https://github.com/aws/aws-sdk-go#getting-help) section. Keeping the list of open issues lean will help us respond in a timely manner. ## Reference Documentation @@ -54,80 +50,397 @@ The GitHub issues are intended for bug reports and feature requests. For help an [`SDK Examples`](https://github.com/aws/aws-sdk-go/tree/master/example) - Included in the SDK's repo are a several hand crafted examples using the SDK features and AWS services. -## Configuring Credentials +## Overview of SDK's Packages + +The SDK is composed of two main components, SDK core, and service clients. +The SDK core packages are all available under the aws package at the root of +the SDK. Each client for a supported AWS service is available within its own +package under the service folder at the root of the SDK. + + * aws - SDK core, provides common shared types such as Config, Logger, + and utilities to make working with API parameters easier. + + * awserr - Provides the error interface that the SDK will use for all + errors that occur in the SDK's processing. This includes service API + response errors as well. The Error type is made up of a code and message. + Cast the SDK's returned error type to awserr.Error and call the Code + method to compare returned error to specific error codes. See the package's + documentation for additional values that can be extracted such as RequestID. + + * credentials - Provides the types and built in credentials providers + the SDK will use to retrieve AWS credentials to make API requests with. + Nested under this folder are also additional credentials providers such as + stscreds for assuming IAM roles, and ec2rolecreds for EC2 Instance roles. + + * endpoints - Provides the AWS Regions and Endpoints metadata for the SDK. + Use this to lookup AWS service endpoint information such as which services + are in a region, and what regions a service is in. Constants are also provided + for all region identifiers, e.g UsWest2RegionID for "us-west-2". + + * session - Provides initial default configuration, and load + configuration from external sources such as environment and shared + credentials file. + + * request - Provides the API request sending, and retry logic for the SDK. + This package also includes utilities for defining your own request + retryer, and configuring how the SDK processes the request. + + * service - Clients for AWS services. All services supported by the SDK are + available under this folder. + +## How to Use the SDK's AWS Service Clients + +The SDK includes the Go types and utilities you can use to make requests to +AWS service APIs. Within the service folder at the root of the SDK you'll find +a package for each AWS service the SDK supports. All service clients follows +a common pattern of creation and usage. + +When creating a client for an AWS service you'll first need to have a Session +value constructed. The Session provides shared configuration that can be shared +between your service clients. When service clients are created you can pass +in additional configuration via the aws.Config type to override configuration +provided by in the Session to create service client instances with custom +configuration. + +Once the service's client is created you can use it to make API requests the +AWS service. These clients are safe to use concurrently. + +## Configuring the SDK + +In the AWS SDK for Go, you can configure settings for service clients, such +as the log level and maximum number of retries. Most settings are optional; +however, for each service client, you must specify a region and your credentials. +The SDK uses these values to send requests to the correct AWS region and sign +requests with the correct credentials. You can specify these values as part +of a session or as environment variables. -Before using the SDK, ensure that you've configured credentials. The best -way to configure credentials on a development machine is to use the -`~/.aws/credentials` file, which might look like: +See the SDK's [configuration guide][config_guide] for more information. +See the [session][session_pkg] package documentation for more information on how to use Session +with the SDK. + +See the [Config][config_typ] type in the [aws][aws_pkg] package for more information on configuration +options. + +[config_guide]: https://docs.aws.amazon.com/sdk-for-go/v1/developer-guide/configuring-sdk.html +[session_pkg]: https://docs.aws.amazon.com/sdk-for-go/api/aws/session/ +[config_typ]: https://docs.aws.amazon.com/sdk-for-go/api/aws/#Config +[aws_pkg]: https://docs.aws.amazon.com/sdk-for-go/api/aws/ + +### Configuring Credentials + +When using the SDK you'll generally need your AWS credentials to authenticate +with AWS services. The SDK supports multiple methods of supporting these +credentials. By default the SDK will source credentials automatically from +its default credential chain. See the session package for more information +on this chain, and how to configure it. The common items in the credential +chain are the following: + + * Environment Credentials - Set of environment variables that are useful + when sub processes are created for specific roles. + + * Shared Credentials file (~/.aws/credentials) - This file stores your + credentials based on a profile name and is useful for local development. + + * EC2 Instance Role Credentials - Use EC2 Instance Role to assign credentials + to application running on an EC2 instance. This removes the need to manage + credential files in production. + +Credentials can be configured in code as well by setting the Config's Credentials +value to a custom provider or using one of the providers included with the +SDK to bypass the default credential chain and use a custom one. This is +helpful when you want to instruct the SDK to only use a specific set of +credentials or providers. + +This example creates a credential provider for assuming an IAM role, "myRoleARN" +and configures the S3 service client to use that role for API requests. + +```go + // Initial credentials loaded from SDK's default credential chain. Such as + // the environment, shared credentials (~/.aws/credentials), or EC2 Instance + // Role. These credentials will be used to to make the STS Assume Role API. + sess := session.Must(session.NewSession()) + + // Create the credentials from AssumeRoleProvider to assume the role + // referenced by the "myRoleARN" ARN. + creds := stscreds.NewCredentials(sess, "myRoleArn") + + // Create service client value configured for credentials + // from assumed role. + svc := s3.New(sess, &aws.Config{Credentials: creds}) ``` -[default] -aws_access_key_id = AKID1234567890 -aws_secret_access_key = MY-SECRET-KEY + +See the [credentials][credentials_pkg] package documentation for more information on credential +providers included with the SDK, and how to customize the SDK's usage of +credentials. + +The SDK has support for the shared configuration file (~/.aws/config). This +support can be enabled by setting the environment variable, "AWS_SDK_LOAD_CONFIG=1", +or enabling the feature in code when creating a Session via the +Option's SharedConfigState parameter. + +```go + sess := session.Must(session.NewSessionWithOptions(session.Options{ + SharedConfigState: session.SharedConfigEnable, + })) ``` -You can learn more about the credentials file from this -[blog post](http://blogs.aws.amazon.com/security/post/Tx3D6U6WSFGOK2H/A-New-and-Standardized-Way-to-Manage-Credentials-in-the-AWS-SDKs). +[credentials_pkg]: ttps://docs.aws.amazon.com/sdk-for-go/api/aws/credentials + +### Configuring AWS Region -Alternatively, you can set the following environment variables: +In addition to the credentials you'll need to specify the region the SDK +will use to make AWS API requests to. In the SDK you can specify the region +either with an environment variable, or directly in code when a Session or +service client is created. The last value specified in code wins if the region +is specified multiple ways. +To set the region via the environment variable set the "AWS_REGION" to the +region you want to the SDK to use. Using this method to set the region will +allow you to run your application in multiple regions without needing additional +code in the application to select the region. + + AWS_REGION=us-west-2 + +The endpoints package includes constants for all regions the SDK knows. The +values are all suffixed with RegionID. These values are helpful, because they +reduce the need to type the region string manually. + +To set the region on a Session use the aws package's Config struct parameter +Region to the AWS region you want the service clients created from the session to +use. This is helpful when you want to create multiple service clients, and +all of the clients make API requests to the same region. + +```go + sess := session.Must(session.NewSession(&aws.Config{ + Region: aws.String(endpoints.UsWest2RegionID), + })) +``` + +See the [endpoints][endpoints_pkg] package for the AWS Regions and Endpoints metadata. + +In addition to setting the region when creating a Session you can also set +the region on a per service client bases. This overrides the region of a +Session. This is helpful when you want to create service clients in specific +regions different from the Session's region. + +```go + svc := s3.New(sess, &aws.Config{ + Region: aws.String(endpoints.UsWest2RegionID), + }) ``` -AWS_ACCESS_KEY_ID=AKID1234567890 -AWS_SECRET_ACCESS_KEY=MY-SECRET-KEY + +See the [Config][config_typ] type in the [aws][aws_pkg] package for more information and additional +options such as setting the Endpoint, and other service client configuration options. + +[endpoints_pkg]: https://docs.aws.amazon.com/sdk-for-go/api/aws/endpoints/ + +## Making API Requests + +Once the client is created you can make an API request to the service. +Each API method takes a input parameter, and returns the service response +and an error. The SDK provides methods for making the API call in multiple ways. + +In this list we'll use the S3 ListObjects API as an example for the different +ways of making API requests. + + * ListObjects - Base API operation that will make the API request to the service. + + * ListObjectsRequest - API methods suffixed with Request will construct the + API request, but not send it. This is also helpful when you want to get a + presigned URL for a request, and share the presigned URL instead of your + application making the request directly. + + * ListObjectsPages - Same as the base API operation, but uses a callback to + automatically handle pagination of the API's response. + + * ListObjectsWithContext - Same as base API operation, but adds support for + the Context pattern. This is helpful for controlling the canceling of in + flight requests. See the Go standard library context package for more + information. This method also takes request package's Option functional + options as the variadic argument for modifying how the request will be + made, or extracting information from the raw HTTP response. + + * ListObjectsPagesWithContext - same as ListObjectsPages, but adds support for + the Context pattern. Similar to ListObjectsWithContext this method also + takes the request package's Option function option types as the variadic + argument. + +In addition to the API operations the SDK also includes several higher level +methods that abstract checking for and waiting for an AWS resource to be in +a desired state. In this list we'll use WaitUntilBucketExists to demonstrate +the different forms of waiters. + + * WaitUntilBucketExists. - Method to make API request to query an AWS service for + a resource's state. Will return successfully when that state is accomplished. + + * WaitUntilBucketExistsWithContext - Same as WaitUntilBucketExists, but adds + support for the Context pattern. In addition these methods take request + package's WaiterOptions to configure the waiter, and how underlying request + will be made by the SDK. + +The API method will document which error codes the service might return for +the operation. These errors will also be available as const strings prefixed +with "ErrCode" in the service client's package. If there are no errors listed +in the API's SDK documentation you'll need to consult the AWS service's API +documentation for the errors that could be returned. + +```go + ctx := context.Background() + + result, err := svc.GetObjectWithContext(ctx, &s3.GetObjectInput{ + Bucket: aws.String("my-bucket"), + Key: aws.String("my-key"), + }) + if err != nil { + // Cast err to awserr.Error to handle specific error codes. + aerr, ok := err.(awserr.Error) + if ok && aerr.Code() == s3.ErrCodeNoSuchKey { + // Specific error code handling + } + return err + } + + // Make sure to close the body when done with it for S3 GetObject APIs or + // will leak connections. + defer result.Body.Close() + + fmt.Println("Object Size:", aws.StringValue(result.ContentLength)) ``` -### AWS shared config file (`~/.aws/config`) -The AWS SDK for Go added support the shared config file in release [v1.3.0](https://github.com/aws/aws-sdk-go/releases/tag/v1.3.0). You can opt into enabling support for the shared config by setting the environment variable `AWS_SDK_LOAD_CONFIG` to a truthy value. See the [Session](https://github.com/aws/aws-sdk-go/wiki/sessions) wiki for more information about this feature. +### API Request Pagination and Resource Waiters -## Using the Go SDK +Pagination helper methods are suffixed with "Pages", and provide the +functionality needed to round trip API page requests. Pagination methods +take a callback function that will be called for each page of the API's response. -To use a service in the SDK, create a service variable by calling the `New()` -function. Once you have a service client, you can call API operations which each -return response data and a possible error. +```go + objects := []string{} + err := svc.ListObjectsPagesWithContext(ctx, &s3.ListObjectsInput{ + Bucket: aws.String(myBucket), + }, func(p *s3.ListObjectsOutput, lastPage bool) bool { + for _, o := range p.Contents { + objects = append(objects, aws.StringValue(o.Key)) + } + return true // continue paging + }) + if err != nil { + panic(fmt.Sprintf("failed to list objects for bucket, %s, %v", myBucket, err)) + } + + fmt.Println("Objects in bucket:", objects) +``` -To list a set of instance IDs from EC2, you could run: +Waiter helper methods provide the functionality to wait for an AWS resource +state. These methods abstract the logic needed to to check the state of an +AWS resource, and wait until that resource is in a desired state. The waiter +will block until the resource is in the state that is desired, an error occurs, +or the waiter times out. If a resource times out the error code returned will +be request.WaiterResourceNotReadyErrorCode. ```go -package main - -import ( - "fmt" - - "github.com/aws/aws-sdk-go/aws" - "github.com/aws/aws-sdk-go/aws/session" - "github.com/aws/aws-sdk-go/service/ec2" -) - -func main() { - sess, err := session.NewSession() - if err != nil { - panic(err) - } - - // Create an EC2 service object in the "us-west-2" region - // Note that you can also configure your region globally by - // exporting the AWS_REGION environment variable - svc := ec2.New(sess, &aws.Config{Region: aws.String("us-west-2")}) - - // Call the DescribeInstances Operation - resp, err := svc.DescribeInstances(nil) - if err != nil { - panic(err) - } - - // resp has all of the response data, pull out instance IDs: - fmt.Println("> Number of reservation sets: ", len(resp.Reservations)) - for idx, res := range resp.Reservations { - fmt.Println(" > Number of instances: ", len(res.Instances)) - for _, inst := range resp.Reservations[idx].Instances { - fmt.Println(" - Instance ID: ", *inst.InstanceId) - } - } -} + err := svc.WaitUntilBucketExistsWithContext(ctx, &s3.HeadBucketInput{ + Bucket: aws.String(myBucket), + }) + if err != nil { + aerr, ok := err.(awserr.Error) + if ok && aerr.Code() == request.WaiterResourceNotReadyErrorCode { + fmt.Fprintf(os.Stderr, "timed out while waiting for bucket to exist") + } + panic(fmt.Errorf("failed to wait for bucket to exist, %v", err)) + } + fmt.Println("Bucket", myBucket, "exists") ``` -You can find more information and operations in our -[API documentation](http://docs.aws.amazon.com/sdk-for-go/api/). +## Complete SDK Example + +This example shows a complete working Go file which will upload a file to S3 +and use the Context pattern to implement timeout logic that will cancel the +request if it takes too long. This example highlights how to use sessions, +create a service client, make a request, handle the error, and process the +response. + +```go + package main + + import ( + "context" + "flag" + "fmt" + "os" + "time" + + "github.com/aws/aws-sdk-go/aws" + "github.com/aws/aws-sdk-go/aws/awserr" + "github.com/aws/aws-sdk-go/aws/request" + "github.com/aws/aws-sdk-go/aws/session" + "github.com/aws/aws-sdk-go/service/s3" + ) + + // Uploads a file to S3 given a bucket and object key. Also takes a duration + // value to terminate the update if it doesn't complete within that time. + // + // The AWS Region needs to be provided in the AWS shared config or on the + // environment variable as `AWS_REGION`. Credentials also must be provided + // Will default to shared config file, but can load from environment if provided. + // + // Usage: + // # Upload myfile.txt to myBucket/myKey. Must complete within 10 minutes or will fail + // go run withContext.go -b mybucket -k myKey -d 10m < myfile.txt + func main() { + var bucket, key string + var timeout time.Duration + + flag.StringVar(&bucket, "b", "", "Bucket name.") + flag.StringVar(&key, "k", "", "Object key name.") + flag.DurationVar(&timeout, "d", 0, "Upload timeout.") + flag.Parse() + + // All clients require a Session. The Session provides the client with + // shared configuration such as region, endpoint, and credentials. A + // Session should be shared where possible to take advantage of + // configuration and credential caching. See the session package for + // more information. + sess := session.Must(session.NewSession()) + + // Create a new instance of the service's client with a Session. + // Optional aws.Config values can also be provided as variadic arguments + // to the New function. This option allows you to provide service + // specific configuration. + svc := s3.New(sess) + + // Create a context with a timeout that will abort the upload if it takes + // more than the passed in timeout. + ctx := context.Background() + var cancelFn func() + if timeout > 0 { + ctx, cancelFn = context.WithTimeout(ctx, timeout) + } + // Ensure the context is canceled to prevent leaking. + // See context package for more information, https://golang.org/pkg/context/ + defer cancelFn() + + // Uploads the object to S3. The Context will interrupt the request if the + // timeout expires. + _, err := svc.PutObjectWithContext(ctx, &s3.PutObjectInput{ + Bucket: aws.String(bucket), + Key: aws.String(key), + Body: os.Stdin, + }) + if err != nil { + if aerr, ok := err.(awserr.Error); ok && aerr.Code() == request.CanceledErrorCode { + // If the SDK can determine the request or retry delay was canceled + // by a context the CanceledErrorCode error code will be returned. + fmt.Fprintf(os.Stderr, "upload canceled due to timeout, %v\n", err) + } else { + fmt.Fprintf(os.Stderr, "failed to upload object, %v\n", err) + } + os.Exit(1) + } + + fmt.Printf("successfully uploaded file to %s/%s\n", bucket, key) + } +``` ## License |