Amazon Textract
Developer Guide

Overview of Managing Access Permissions to Your Amazon Textract Resources

Every AWS resource is owned by an AWS account, and permissions to create or access a resource are governed by permissions policies. An account administrator can attach permissions policies to IAM identities (that is, users, groups, and roles). Some services (such as AWS Lambda) also support attaching permissions policies to resources.

Note

An account administrator (or administrator user) is a user with administrator permissions. For more information, see IAM Best Practices in the IAM User Guide.

When granting permissions, you decide who is getting the permissions, the resources they get permissions for, and the specific actions that you want to allow on those resources.

Amazon Textract Resources and Operations

In Amazon Textract, the primary resource is an asynchronous job. As mentioned previously, asynchronous job don't have Amazon Resource Names (ARNs) associated with them. However, some other services that you use with Amazon Textract do have unique ARNs associated with their resources. For example, you can use Amazon S3 buckets to store documents that are used by the Amazon Textract API. The following table shows the ARNs for an Amazon S3 bucket and the key that's used to identify the stored object (document image file) in the bucket.

Resource Type ARN Format
Amazon S3 bucket ARN arn:aws:s3:::bucket_name
Amazon S3 object ARN arn:aws:s3:::bucket_name/key_name

Amazon Textract provides a set of operations to work with documents. For a list of available operations, see Amazon Textract API Reference.

Understanding Resource Ownership

The AWS account owns the resources that are created in the account, regardless of who created the resources. Specifically, the resource owner is the AWS account of the principal entity (that is, the root account or an IAM user) that authenticates the resource creation request. The following examples illustrate how this works:

  • If you use the root account credentials of your AWS account to create an asynchronous job, your AWS account is the owner of the resource (in Amazon Textract, the resource is an asynchronous job).

  • If you create an IAM user in your AWS account and grant permissions to create an asynchronous job to that user, the user can create an asynchronous job. However, your AWS account, to which the user belongs, owns the asynchronous job resource.

Managing Access to Resources

A permissions policy describes who has access to which resources. The following section explains the available options for creating permissions policies.

Note

This section discusses using IAM in the context of Amazon Textract. It doesn't provide detailed information about the IAM service. For complete IAM documentation, see What Is IAM? in the IAM User Guide. For information about IAM policy syntax and descriptions, see AWS IAM Policy Reference in the IAM User Guide.

Policies attached to an IAM identity are referred to as identity-based policies (IAM policies). Policies attached to a resource are referred to as resource-based policies. Amazon Textract supports identity-based policies.

Identity-based Policies (IAM Policies)

You can attach policies to IAM identities. For example, you can do the following:

  • Attach a permissions policy to a user or a group in your account – To grant a user permissions to create an Amazon Textract resource, such as an asynchronous job, you can attach a permissions policy to a user or group that the user belongs to.

  • Attach a permissions policy to a role (grant cross-account permissions) – You can attach an identity-based permissions policy to an IAM role to grant cross-account permissions. For example, the administrator in account A can create a role to grant cross-account permissions to another AWS account (for example, account B) or an AWS service as follows:

    1. The account A administrator creates an IAM role and attaches a permissions policy to the role that grants permissions on resources in account A.

    2. The account A administrator attaches a trust policy to the role that identifies account B as the principal who can assume the role.

    3. The account B administrator can then delegate permissions to assume the role to any users in account B. Doing this allows users in account B to create or access resources in account A. The principal in the trust policy can also be an AWS service principal if you want to grant an AWS service permissions to assume the role.

    For more information about using IAM to delegate permissions, see Access Management in the IAM User Guide.

The following is an example policy that allows access to the DetectDocumentText operation.

"Version": "2012-10-17", "Statement": [ { "Sid": "AllowsTextDetection", "Effect": "Allow", "Action": [ "textract:DetectDocumentText" ], "Resource": "*" } ] }

For more information about using identity-based policies with Amazon Textract, see Using Identity-based Policies (IAM Policies) for Amazon Textract. For more information about users, groups, roles, and permissions, see Identities (Users, Groups, and Roles) in the IAM User Guide.

Resource-based Policies

Other services, such as Amazon S3, also support resource-based permissions policies. For example, you can attach a policy to an S3 bucket to manage access permissions to that bucket. Amazon Textract doesn't support resource-based policies.

To access images stored in an Amazon S3 bucket, you must have permission to access objects in the S3 bucket. With this permission, Amazon Textract can download images from the S3 bucket. The following example policy allows the user to perform the s3:GetObject action on the S3 bucket named Tests3bucket.

{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": "s3:GetObject", "Resource": [ "arn:aws:s3:::Tests3bucket" ] } ] }

To use an S3 bucket with versioning enabled, add the s3:GetObjectVersion action, as shown in the following example.

{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Action": [ "s3:GetObject", "s3:GetObjectVersion" ], "Resource": [ "arn:aws:s3:::Tests3bucket" ] } ]

Specifying Policy Elements: Actions, Effects, and Principals

For each Amazon Textract resource, the service defines a set of API operations. To grant permissions for these API operations, Amazon Textract defines a set of actions that you can specify in a policy. Some API operations can require permissions for more than one action in order to perform the API operation. For more information about resources and API operations, see Amazon Textract Resources and Operations and Amazon Textract API Permissions: Actions, Permissions, and Resources Reference.

The following are the most basic policy elements:

  • Resource – You use an Amazon Resource Name (ARN) to identify the resource that the policy applies to. For more information, see Amazon Textract Resources and Operations.

  • Action – You use action keywords to identify resource operations that you want to allow or deny. For example, you can use ListCollections to list collections.

  • Effect – You specify the effect, either allow or deny, when the user requests the specific action. If you don't explicitly grant access to (allow) a resource, access is implicitly denied. You can also explicitly deny access to a resource, which you might do to make sure that a user can't access it, even if a different policy grants access.

  • Principal – In identity-based policies (IAM policies), the user that the policy is attached to is the implicit principal. For resource-based policies, you specify the user, account, service, or other entity that you want to receive permissions (applies to resource-based policies only). Amazon Textract doesn't support resource-based policies.

To learn more about IAM policy syntax and descriptions, see AWS IAM Policy Reference in the IAM User Guide.

For a table showing all of the Amazon Textract API operations and the resources that they apply to, see Amazon Textract API Permissions: Actions, Permissions, and Resources Reference.

Specifying Conditions in a Policy

When you grant permissions, you can use the access-policy language to specify the conditions when a policy should take effect. For example, you might want a policy to be applied only after a specific date. For more information about specifying conditions in a policy language, see Condition in the IAM User Guide.

To express conditions, you use predefined condition keys. There are no condition keys specific to Amazon Textract. However, there are AWS-wide condition keys that you can use as appropriate. For a complete list of AWS-wide keys, see Available Keys for Conditions in the IAM User Guide.