What's new in ApexLib?

Transcript

1. What’s new in ApexLib Chris “@ca_peterson” Peterson June 4th, 2014

2. How do we query? It all starts off so simple:

   Contact notBob = [SELECT Name, Id FROM Contact WHERE Name != ‘Bob’ LIMIT 1];

3. How do we query? But it can get ugly fast:

   //ewww String soql = ‘SELECT ‘; for(Integer i = 0; i< fieldList.size(); i++){ soql += fieldList + ‘, ‘; } soql = soql.substring(0,soql.length()-2); soql += conditions != null && conditions.trim().size() > 0 ? ‘ WHERE ‘ + soqlConditions : ‘’; soql += limit != null && limit.trim().size() > 0 ? ‘ LIMIT ‘+limit; List<Contact> nonBobs = Database.query(soql);

4. Introducing QueryFactory • Object-oriented. No string building. • Enables flexible

   selector layers. • Idempotent operations (where sane). • Field-set friendly. • Package-friendly (implies namespaces)

5. What’s so bad about string building? • Did you see

   that earlier slide? • Fails late, well after when errors were introduced. • Stream-like: you can’t (easily) amend a previous clause.

6. Why not apex-commons SOQLBuilder? Initially planned to, but… • Massive,

   verbose. • No updates in quite a while. • Not idempotent, reduces encapsulation.

7. Results in: SELECT Name FROM Contact Limit 5 In it’s

   simplest form: new fflib_QueryFactory(Contact.SObjectType) .selectField(‘name’) .setLimit(5) .toSOQL(); So how do I use it?

8. fflib_QueryFactory qf = new fflib_QueryFactory(Contact.SObjectType) .selectField(Contact.SObjectType.fields.name) .selectField(‘name’) //ignored: name already

   selected .selectFieldSet( Schema.SObjectType.Contact.fieldSets.MyFieldSet ) .setLimit(5); qf.setCondition(‘Name != “Bob”’); qf.setLimit(10); //overrides the earlier limit Results in: SELECT Name, <MyFieldSet’s fields> FROM Contact WHERE Name != “Bob” LIMIT 10 With a field set

9. When should I use it? • Field sets. • Dynamic

   queries. • Extensible selector classes.

10. When should I go another route? • When queries are

    static. • When performance is more critical than code quality. • When you need aggregations. • Weird SOQL edge cases, like toLabel().

11. Future Plans • Bind variable support • Object and field

    read permission checks • Better cross-object field selects • Support for aggregations • Object-oriented where clauses (#safeharbor)

12. Questions? Twitter: @ca_peterson irc.freenode.net #salesforce: ca_peterson Code on Github: https://github.com/financialforcedev/fflib-

    apex-common Slides available at https://speakerdeck.com/ca_peterson