Re: ERXPrefixQualifierTraversal usage example (@daveeed)
Re: ERXPrefixQualifierTraversal usage example (@daveeed)
- Subject: Re: ERXPrefixQualifierTraversal usage example (@daveeed)
- From: Chuck Hill <email@hidden>
- Date: Thu, 10 Jun 2010 13:57:29 -0700
On Jun 10, 2010, at 1:48 PM, Kieran Kelleher wrote:
(In reply to David's tweet - answer too long for twitter!.... and
twitlonger makes the sentences wrap too much....)
__________________________________________________________
David's question:
@kierankelleher would you mind showing me an example of how it is
used? It sounds like something that could be used with D2W for
permissions
__________________________________________________________
@daveeed
For example, in one of my apps, the User entity has a
"customersQualifier()" method that returns a qualifier appropriate
to the Role of the user that qualifies the user's access to Customer
objects in the system. The Qualifier is constructed differently for
customer users, inside sales, sysadmin, graphic design, etc. The
qualifier itself is based on Customer attributes and in itself is
useful only for fetches against the Customer entity.
Now let's say I have Barcoded Coupons on Mailers, and someone is
scanning Coupon redemptions into a web form for tracking and
reporting of advertizement effectiveness and let's say I want to
make sure that the person scanning has access to the customer that
is related to those coupons. And in this scenario, let's say the
relationship keyPath from Coupon Entity to Customer Entity is like
this:
coupon -> mailer.campaign.program.location.customer
So when the coupon ID is scanned in and submitted, I can create a
Qualifier for the Coupon based on the ID, and then I need an
auxiliary security qualifier to ensure the logged in user has access
to the related Customer so I would do sth like these steps:
EOQualifier qCoupon = Coupon.XKEY_SERIAL_ID.eq( scannedCouponID );
EOQualifier qCustomer = currentUser.customerQualifier();
// Since qCustomer qualifies Customer entities and we want to
qualify the Coupon that we are fetching based on
// the user's restricted access to a specific set of Customer EOs...
prefix the customer qualifier to make it a coupon qualifier
// that restricts the fetch to coupons related to the customers that
this user has access to....
qCustomer =
ERXPrefixQualifierTraversal
.prefixQualifierWithKey
( "mailer.campaign.program.location.customer" );
qCustomer =
ERXPrefixQualifierTraversal.prefixQualifierWithKey(qCustomer,
"mailer.campaign.program.location.customer" );
you mean?
EOQualifier qFinal = ERXQ.and( qCoupon, qCustomer );
Coupon c = ( fetch with qualifier 'qFinal' )
I hope that explains the usage of ERXPrefixQualifierTraversal
better ....
Regards, Kieran
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden
--
Chuck Hill Senior Consultant / VP Development
Practical WebObjects - for developers who want to increase their
overall knowledge of WebObjects or who are trying to solve specific
problems.
http://www.global-village.net/products/practical_webobjects
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Webobjects-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden