Since this issue was entered in Red Hat Bugzilla, the release flag has been
set to ? to ensure that it is properly evaluated for this release.

I believe that these can be addressed upstream. I am moving to ON_QE to verify.

organizations/<id>/repositories is expressed as
http://localhost:3330/katello/api/v2/repositories?organization_id=<id>

products/<id>/repositories is expressed as
http://localhost:3330/katello/api/v2/repositories?organization_id=<id>&product_id=<id>

products/<id>/repositories is expressed as
http://localhost:3330/katello/api/v2/repositories?organization_id=<id>&environment_id=<id>

It is possible to fetch a set of repositories filtered according to the organization, product and environment that the repositories belong to.

As proof, here's a python script that I executed:

    #!/usr/bin/env python
    from robottelo import entities
    from nailgun import client
    from robottelo.common.helpers import get_server_credentials

    # Start by creating an organization, product and repository.
    ORG_ID = entities.Organization().create_json()['id']
    PROD_ID = entities.Product(organization=ORG_ID).create_json()['id']
    REPO_ID = entities.Repository(product=PROD_ID).create_json()['id']

    # Read back data from the server using suggested paths. First provide just an
    # organization ID.
    response = client.get(
        entities.Repository().path(),
        verify=False,
        auth=get_server_credentials(),
        data={'organization_id': ORG_ID}
    )
    print(response.status_code)
    print(response.json()['total'])

    # Second, provide an organization and product ID.
    response = client.get(
        entities.Repository().path(),
        verify=False,
        auth=get_server_credentials(),
        data={'organization_id': ORG_ID, 'product_id': PROD_ID}
    )
    print(response.status_code)
    print(response.json()['total'])

    # Third, provide an organization and environment ID. The environment ID should
    # not match anything.
    response = client.get(
        entities.Repository().path(),
        verify=False,
        auth=get_server_credentials(),
        data={'organization_id': ORG_ID, 'environment_id': 123456}
    )
    print(response.status_code)
    print(response.json()['total'])

And here's the output:

    200
    1
    200
    1
    200
    0

This bugzilla is about inconsistency in the API routes.

See below the difference in routes for repositories, cotnent_views and products:
- The repositories does not have a /organizations/ route
- The repositories does have a /content_views/, but not a /products/ route

  api :GET, "/repositories", N_("List of enabled repositories")
  api :GET, "/content_views/:id/repositories", N_("List of repositories for a content view")
  param :organization_id, :number, :required => true, :desc => N_("ID of an organization to show repositories in")
  param :product_id, :number, :desc => N_("ID of a product to show repositories of")

For example the content_views has a route with /organizations/

    api :GET, "/organizations/:organization_id/content_views", N_("List content views")
    api :GET, "/content_views", N_("List content views")
    param :organization_id, :number, :desc => N_("organization identifier"), :required => true

And products has even more routes:

    api :GET, "/products", N_("List products")
    api :GET, "/subscriptions/:subscription_id/products", N_("List of subscription products in a subscription")
    api :GET, "/activation_keys/:activation_key_id/products", N_("List of subscription products in an activation key")
    api :GET, "/organizations/:organization_id/products", N_("List of products in an organization")
    param :organization_id, :number, :desc => N_("Filter products by organization"), :required => true

Still open, also for Sat6.1.0 that has only content_views/ route

/opt/rh/ruby193/root/usr/share/gems/gems/katello-2.2.0.51/app/controllers/katello/api/v2# grep GET repositories_controller.rb
    api :GET, "/repositories", N_("List of enabled repositories")
    api :GET, "/content_views/:id/repositories", N_("List of repositories for a content view")
    api :GET, "/repositories/:id", N_("Show a custom repository")
    api :GET, "/repositories/:id/gpg_key_content", N_("Return the content of a repo gpg key, used directly by yum")

This bug is slated to be released with Satellite 6.1.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHSA-2015:1592