Salesforce Certified MuleSoft Developer free question 1 / 10 · Domain 1: Creating Application Networks
A mobile app calls the Mule app orders-api and nothing calls the mobile app. Orders-api calls a database, and the database calls nothing. When the application network is viewed as a graph, how are the mobile app and the database placed?
- Neither appears, because only deployed Mule apps become nodes
- Both next to orders-api in one row, as parts of its base unit
- The database at the top and the mobile app at the bottom of the graph
- The mobile app at the top and the database at the bottom of the graph
Show the answer and explanation
Answer: D
Why this is correct
API Visualizer shows a graph of the application network. Its base unit is a Mule application deployed and running on a supported Mule instance, and the nodes around it are placed by the direction of their connections. To keep the graph readable, consumer nodes, which have only outbound connections, are shown at the top. Backend systems, which have only inbound connections, are shown at the bottom. The mobile app only calls out, so it is a consumer node at the top. The database only receives calls, so it is a backend system at the bottom. Orders-api has both inbound and outbound connections and sits between them. Read top to bottom, the graph follows a request from the caller down to the system of record.
Why the other options are wrong
"The database at the top and the mobile app at the bottom of the graph" … This reverses the rule. A node with only inbound connections, like the database, is a backend system and is shown at the bottom; the top is for consumer nodes with only outbound connections.
"Both next to orders-api in one row, as parts of its base unit" … The base unit of the graph is a Mule application that is deployed and running on a supported Mule instance. Callers and backends are separate nodes, placed by the direction of their connections.
"Neither appears, because only deployed Mule apps become nodes" … The Mule app is the base unit, but the graph also shows consumer nodes and backend systems. The page places them explicitly, at the top and at the bottom, so they do appear.
Callers at the top, systems at the bottom
The layout matches how an application network is usually drawn: consumers above, the APIs that serve them in the middle, and backend systems below. If a node you expect at the bottom appears at the top, check its connections; a system that also calls out is no longer a backend-only node.