Current Release

This documentation covers the current version of Fedora. Looking for another version? See all documentation.

In this quick start, you will create a sample resource and an ACL for that resource, verify that access to that resource is correctly restricted, and finally modify the ACL to allow you to update the resource.

Prerequisites

  • a running Fedora repository
  • curl

The commands in this guide assume that your Fedora repository root is http://localhost:8080/fcrepo/rest.

Steps

Create these two files:

foo.ttl
@prefix dc: <http://purl.org/dc/elements/1.1/>.

<> dc:title "Hello, World!".
acl.ttl
@prefix acl: <http://www.w3.org/ns/auth/acl#>.

<#authz> a acl:Authorization;
   acl:accessTo </fcrepo/rest/foo>;
   acl:agent "user1";
   acl:mode acl:Read.

Upload these files into the repository:

curl -X PUT http://localhost:8080/fcrepo/rest/foo -u admin1:password3 \
    -H "Content-Type: text/turtle" --data-binary @foo.ttl
curl -X PUT http://localhost:8080/fcrepo/rest/foo/fcr:acl -u admin1:password3 \
    -H "Content-Type: text/turtle" --data-binary @acl.ttl

Now user1 is able to read the resource at http://localhost:8080/rest/foo, but user2 cannot. To test this, try the following two commands:

curl -i http://localhost:8080/fcrepo/rest/foo -u user1:password1
curl -i http://localhost:8080/fcrepo/rest/foo -u user2:password2

The first request should succeed with a 200 OK response code, and the second should fail with a 403 Forbidden.

To demonstrate that user1 indeed only has read-only access to foo, we can try updating foo. Create a file named foo.sparql with the following contents:

foo.sparql
PREFIX dc: <http://purl.org/dc/elements/1.1/>

INSERT DATA { <> dc:description "Quick Start with WebAC and Fedora 4" . }

Then run this to attempt to update foo:

curl -i -X PATCH http://localhost:8080/fcrepo/rest/foo -u user1:password1 \
      -H "Content-Type: application/sparql-update" \
      --data-binary @foo.sparql

This request should fail with a 403 Forbidden response, since user1 has read-only access to foo. To add write access for user1, we will need to update the acl/authz resource as admin. Create a file named authz.sparql with the following contents:

authz.sparql
PREFIX acl: <http://www.w3.org/ns/auth/acl#>

INSERT DATA { <#authz> acl:mode acl:Write . }

Run this command to update the ACL authorization:

curl -i -X PATCH http://localhost:8080/fcrepo/rest/acl/authz -u admin1:password3 \
      -H "Content-Type: application/sparql-update" \
      --data-binary @authz.sparql

If the update to the authorization was successful, you will see a 204 No Content response.

Now you should be able to re-run the earlier command to update the foo resource as user1:

curl -i -X PATCH http://localhost:8080/fcrepo/rest/foo -u user1:password1 \
      -H "Content-Type: application/sparql-update" \
      --data-binary @foo.sparql

Now this should return a 204 No Content response. To verify that the update happened, you can also go to http://localhost:8080/fcrepo/rest/foo in your web browser, and confirm that it has both dc:title and dc:description properties.

ACLs for the Repository Root

When creating an ACL to protect the repository root, you must include a trailing slash in the Authorizations's acl:accessTo predicate, otherwise the Authorization will not match the request URI, and won't get applied.

Non-Working Version
<#rootAuthz> a acl:Authorization;
    acl:accessTo <https://localhost:8080/fcrepo/rest> .
Working Version
<#rootAuthz> a acl:Authorization;
    acl:accessTo <https://localhost:8080/fcrepo/rest/> .
    # note this trailing slash ---------------------^
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