How to Safely Access Nested Object Keys

[sarp.acikelli]

Goal

Learn how to safely access nested object keys in Autom Mate without running into Variable usage error: Key not found.

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When to Use

• When working with JSON objects or structured data returned from connectors.

• If some keys may be optional or missing.

• To avoid null vs error inconsistencies between object[key] and object[key][subkey].

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Step-by-Step

1. Direct Key Access

   • Accessing a top-level key:

     ##object[knownKey]##   → returns value or null if not found   
     

2. Nested Key Access

   • If the parent key exists but the subkey doesn’t, Autom Mate currently throws:

     Variable usage error. Key not found  
     
     

3. Safe Checking with if and has property condition

   • Check before accessing deeper levels:

     

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Architecture / Flow

• Without check → object[key][subkey] → throws error if key is missing.

• With safe access → staged lookup → null returned instead of breaking execution.

object ──["key"]──┬── null  → safe return
                  └── object ──["subkey"]──→ value / null

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Validation

• Test with an object missing the parent key: should not fail.

• Test with a missing subkey under an existing parent: should return null safely.

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Troubleshooting

• Error: Variable usage error. Key not found → indicates direct nested access without validation.

• Fix: Always check parent key existence before drilling deeper.

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Best Practices

• Use intermediate variables to simplify nested lookups.

• Apply has property condition before accessing deeper levels.

• Treat null as an expected safe fallback, not an error.