ARM template structure in Azure - Step-by-Step Execution

Process Flow - ARM template structure

Start ARM Template

↓

Define $schema

↓

Set contentVersion

↓

Declare parameters

↓

Declare variables

↓

Define resources

↓

Declare outputs

↓

End Template

The ARM template starts with schema and version, then defines parameters, variables, resources, and outputs in order.

Execution Sample

Azure

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {},
  "variables": {},
  "resources": [],
  "outputs": {}
}

This is a minimal ARM template structure showing all main sections.

Process Table

Step	Section Processed	Action	Result
1	$schema	Read and validate schema URL	Template schema set for ARM validation
2	contentVersion	Read version string	Template version set to 1.0.0.0
3	parameters	Parse parameters object	Parameters ready for input values
4	variables	Parse variables object	Variables ready for internal use
5	resources	Parse resources array	Resources defined for deployment
6	outputs	Parse outputs object	Outputs defined for deployment results
7	End	Complete parsing	Template ready for deployment

💡 All sections processed; template structure is valid and ready for deployment

Status Tracker

Section	Start	After Processing
$schema	Not set	https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#
contentVersion	Not set	1.0.0.0
parameters	Empty	{}
variables	Empty	{}
resources	Empty	[]
outputs	Empty	{}

Key Moments - 3 Insights

Why is the $schema property important in an ARM template?

The $schema property tells Azure how to validate the template structure and syntax. Without it, Azure cannot confirm the template is correct (see execution_table step 1).

Can the resources section be empty in a valid ARM template?

Yes, the resources array can be empty if no resources are being deployed, but the template still needs to include it (see execution_table step 5).

What is the purpose of the outputs section?

Outputs provide information back after deployment, like resource IDs or connection strings. They are optional but useful (see execution_table step 6).

Visual Quiz - 3 Questions

Look at the execution_table, what is the result after processing the parameters section?

A Resources defined for deployment

B Template version set to 1.0.0.0

C Parameters ready for input values

D Outputs defined for deployment results

💡 Hint

Check execution_table row with Section Processed 'parameters'

At which step does the ARM template finish parsing all sections?

A Step 5

B Step 7

C Step 6

D Step 4

💡 Hint

Look for the row with Section Processed 'End' in execution_table

If the variables section is removed, which part of the variable_tracker would change?

A The variables row value

B The $schema value

C The outputs row value

D The resources row value

💡 Hint

Check variable_tracker row for 'variables' section

Concept Snapshot

ARM Template Structure:
- $schema: URL for template validation
- contentVersion: template version
- parameters: inputs for deployment
- variables: internal values
- resources: Azure resources to create
- outputs: values returned after deployment
All sections must be valid JSON objects or arrays.

Full Transcript

An ARM template is a JSON file that defines Azure resources to deploy. It starts with a $schema property that tells Azure how to validate the template. Then it has a contentVersion to track template version. Parameters allow users to input values when deploying. Variables store internal values used in the template. Resources define what Azure services to create or configure. Outputs return information after deployment. Each section is processed in order, and the template must be valid JSON to deploy successfully.