Salesforce Fundamentals18% of the exam
Declarative limits, invocable Apex and custom components
When configuration is enough and when code is justified: the declarative-first rule, the HTTP Callout action with named and external credentials, invocable Apex actions in flows, and when a custom Lightning web component is the answer.
Given a scenario, identify the boundaries of declarative customization and the use cases for programmatic customization.
~8 min read · 10 practice questions ·
What the exam expects
- Apply the "declarative first" rule and name the signals that justify code: logic too complex for configuration, a custom user experience, or heavy record volume.
- Choose the Flow Builder HTTP Callout action for a REST integration and list the credential setup it needs (external credential, named credential, permission set access).
- Explain when a flow should call an invocable Apex action, why
@InvocableMethodreplacesProcess.Plugin, and why a user can fail at that action. - Recognize when a custom Lightning web component is the answer on a record page or a flow screen, and why LWC beats Aura for new work.
- Key terms: declarative (point-and-click configuration); programmatic (Apex, Lightning components, Visualforce); HTTP Callout action (a flow action that calls a REST API without code); named credential (endpoint URL plus a link to authentication); external credential (how Salesforce authenticates to the remote system); invocable Apex action (an Apex method a flow calls as an Action element).
Key facts
Recommended order
- Detail
- Declarative first; add code for complex logic or a custom UX; fully programmatic last
Setup order
- Detail
- Permission set, auth provider (OAuth only), external credential, named credential, then User Credentials access
Callout errors
- Detail
- Status 300 or greater is an error; handle it with a fault path
Callouts in record-triggered flows
- Detail
- Only on the asynchronous path, after the save commits
Apex from a flow
- Detail
- Running user needs the Apex class in a profile or permission set
@InvocableMethod data types- Detail
- No generic Object, Sets, Maps or Enums
LWC in a flow screen
- Detail
lightning__FlowScreentarget plustargetConfigproperties
LWC and Aura nesting
- Detail
- Aura can wrap LWC; an LWC can't contain Aura
Sources for this section (7)
- Explore Essential Toolstrailhead.salesforce.com (opens in a new tab)
- HTTP Callout Authenticationhelp.salesforce.com (opens in a new tab)
- HTTP Callout Limitshelp.salesforce.com (opens in a new tab)
- Record-Triggered Flow Considerationshelp.salesforce.com (opens in a new tab)
- Apex Actionshelp.salesforce.com (opens in a new tab)
- Configure for Flow Screensdeveloper.salesforce.com (opens in a new tab)
- LWC or Auradeveloper.salesforce.com (opens in a new tab)
- Why does Salesforce recommend trying declarative tools before code?
- Why are the named credential and the external credential separate?
- Why must a record-triggered flow's callout go on an asynchronous path?
- Which two features does
@InvocableMethodoffer thatProcess.Pluginlacks for flow performance and setup?
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