Repository policies
CodeArtifact uses resource-based permissions to control access. Resource-based permissions let you specify who has access to a repository and what actions they can perform on it. By default, only the repository owner has access to a repository. You can apply a policy document that allows other IAM principals to access your repository.
For more information, see Resource-Based Policies and Identity-Based Policies and Resource-Based Policies.
Create a resource policy to grant read access
A resource policy is a text file in JSON format. The file must specify a principal
            (actor), one or more actions, and an effect (Allow or Deny).
          For example, the following resource policy grants the account 123456789012
            permission to download packages from the repository.
Because the policy is evaluated only for operations against the repository that it's
            attached to, you don't need to specify a resource. Because the resource is implied, you
            can set the Resource to *. In order for a package manager to download 
            a package from this repository, a domain policy for cross-account access will also need to be 
            created. The domain policy must grant at least codeartifact:GetAuthorizationToken 
            permission to the principal. For an example of a full domain policy for granting cross-account 
            access, see this Domain policy example.
Note
The codeartifact:ReadFromRepository action can only be used on a
                repository resource. You cannot put a package's Amazon Resource Name (ARN) as a
                resource with codeartifact:ReadFromRepository as the action to allow
                read access to a subset of packages in a repository. A given principal can either
                read all the packages in a repository or none of them.
Because the only action specified in the repository is ReadFromRepository,
            users and roles from account 1234567890 can download packages from the
            repository. However, they can't perform other actions on them (for example, listing
            package names and versions). Typically, you grant permissions in the following policy in
            addition to ReadFromRepository because a user who downloads packages from a
            repository needs to interact with it in other ways too.
Set a policy
After you create a policy document, use the
                put-repository-permissions-policy command to attach it to a
            repository:
aws codeartifact put-repository-permissions-policy --domainmy_domain--domain-owner111122223333\ --repositorymy_repo--policy-documentfile:///PATH/TO/policy.json
When you call put-repository-permissions-policy, the resource policy on the repository is ignored when evaluating permissions. This ensures 
           that the owner of a domain cannot lock themselves out of the repository, which would prevent them from being able to update the resource policy.
Note
You cannot grant permissions to another AWS account to update the resource policy on a repository using a resource policy, since the resource policy is ignored when calling put-repository-permissions-policy.
Sample output:
{ "policy": { "resourceArn": "arn:aws:codeartifact:region-id:111122223333:repository/my_domain/my_repo", "document": "{ ...policy document content...}", "revision": "MQlyyTQRASRU3HB58gBtSDHXG7Q3hvxxxxxxx=" } }
The output of the command contains the Amazon Resource Name (ARN) of the repository
            resource, the full contents of the policy document, and a revision identifier. You can
            pass the revision identifier to put-repository-permissions-policy using the
                --policy-revision option. This ensures that a known revision of the
            document is being overwritten, and not a newer version set by another writer.
Read a policy
Use the get-repository-permissions-policy command to read an existing
            version of a policy document. To format the output for readability, use the
                --output and --query policy.document together with the
            Python json.tool module.
aws codeartifact get-repository-permissions-policy --domainmy_domain--domain-owner111122223333\ --repositorymy_repo--output text --query policy.document | python -m json.tool
Sample output:
Delete a policy
Use the delete-repository-permissions-policy command to delete a policy
            from a repository.
aws codeartifact delete-repository-permissions-policy --domainmy_domain--domain-owner111122223333\ --repositorymy_repo
The format of the output is the same as that of the get-repository-permissions-policy command.
Grant read access to principals
 When you specify the root user of an account as the principal in a policy
                document, you grant access to all of the users and roles in that account. To limit
                access to selected users or roles, use their ARN in the Principal
                section of the policy. For example, use the following to grant read access to the
                IAM user bob in account 123456789012.
Grant write access to packages
 The codeartifact:PublishPackageVersion action is used to control
                permission to publish new versions of a package. The resource used with this action
                must be a package. The format of CodeArtifact package ARNs is as follows.
arn:aws:codeartifact:region-id:111122223333:package/my_domain/my_repo/package-format/package-namespace/package-name
The following example shows the ARN for an npm package with scope
                    @parity and name ui in the my_repo
                repository in domain my_domain. 
arn:aws:codeartifact:region-id:111122223333:package/my_domain/my_repo/npm/parity/ui
The ARN for an npm package without a scope has the empty string for the namespace
                field. For example, the following is the ARN for a package without a scope and with
                name react in the my_repo repository in domain
                    my_domain.
arn:aws:codeartifact:region-id:111122223333:package/my_domain/my_repo/npm//react
The following policy grants account 123456789012 permission to publish
                versions of @parity/ui in the my_repo
                repository.
Important
To grant permission to publish Maven and NuGet package versions, add the following permissions in 
                    addition to codeartifact:PublishPackageVersion.
- NuGet: - codeartifact:ReadFromRepositoryand specify the repository resource
- Maven: - codeartifact:PutPackageMetadata
Because this policy specifies a domain and repository as part of the resource, it allows publishing only when attached to that repository.
Grant write access to a repository
 You can use wildcards to grant write permission for all packages in a repository.
                For example,  use the following policy to grant an account permission to write to
                all packages in the my_repo repository.
Interaction between repository and domain policies
CodeArtifact supports resource policies on domains and repositories. Resource policies are optional. Each domain may have one policy and each repository in the domain may have its own repository policy. If both a domain policy and a repository policy are present, then both are evaluated when determining whether a request to a CodeArtifact repository is allowed or denied. Domain and repository policies are evaluating using the following rules:
- 
                    No resource policies are evaluated when performing account-level operations such as ListDomains or ListRepositories. 
- 
                    No repository policies are evaluated when performing domain-level operations such as DescribeDomain or ListRepositoriesInDomain. 
- 
                    The domain policy is not evaluated when performing PutDomainPermissionsPolicy. Note that this rule prevents lock-outs. 
- 
                    The domain policy is evaluated when performing PutRepositoryPermissionsPolicy, but the repository policy is not evaluated. 
- 
                    An explicit deny in any policy overrides an allow in another policy. 
- 
                    An explicit allow is only required in one resource policy. Omitting an action from a repository policy will not result in an implicit deny if the domain policy allows the action. 
- 
                    When no resource policy allows an action, the result is an implicit deny unless the calling principal’s account is the domain owner or repository administrator account and an identity-based policy allows the action. 
Resource policies are optional when used to grant access in a single account scenario, where the caller account used to access a repository is the same as the domain owner and repository administrator account. Resource policies are required to grant access in a cross-account scenario where the caller’s account is not the same as the domain owner or repository administrator account. Cross-account access in CodeArtifact follows the general IAM rules for cross-account access as described in Determining whether a cross-account request is allowed in the IAM User Guide.
- 
                    A principal in the domain owner account may be granted access to any repository in the domain through an identity-based policy. Note that in this case, no explicit allow is required in a domain or repository policy. 
- 
                    A principal in the domain owner account may be granted access to any repository through a domain or repository policy. Note that in this case, no explicit allow is required in an identity-based policy. 
- 
                    A principal in the repository administrator account may be granted access to the repository through an identity-based policy. Note that in this case, no explicit allow is required in a domain or repository policy. 
- 
                    A principal in another account is only granted access when allowed by at least one resource policy and at least one identity-based policy, with no policy explicitly denying the action.