Azure Logic Apps

Azure Logic Apps is a serverless integration platform that lets you build automated workflows visually. While Azure Functions is code-first, Logic Apps is design-first — you create workflows by connecting pre-built connectors in a visual designer. With over 400 connectors, Logic Apps excels at integrating cloud services, SaaS applications, on-premises systems, and custom APIs without writing significant code.

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Azure Functions vs Logic Apps

Both are serverless and event-driven, but they serve different purposes:

Aspect	Azure Functions	Logic Apps
Approach	Code-first	Design-first (visual)
Development	Write functions in code	Drag-and-drop connectors
State	Stateless (or Durable Functions)	Stateful by default (run history)
Connectors	Custom code, SDKs	400+ pre-built connectors
Monitoring	Application Insights	Built-in run history and tracking
Best for	Custom logic, compute-heavy, algorithms	Integration, workflow automation, SaaS connections
Pricing	Per execution / plan-based	Per action execution or ISE

Use Azure Functions when you need custom code, complex business logic, or high-performance compute. Use Logic Apps when you need to integrate multiple services quickly with minimal code.

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Logic Apps Hosting Models

Consumption (Multi-Tenant)

• Runs in the shared Azure Logic Apps infrastructure
• Pay per action execution and connector call
• Scales automatically
• No VNet integration (without ISE)
• Best for simple integration workflows

Standard (Single-Tenant)

• Runs on Azure App Service infrastructure (or locally)
• Multiple workflows per Logic App resource
• VNet integration and private endpoints
• Built on the Azure Functions runtime
• Deploy with CI/CD pipelines
• Best for enterprise workloads requiring network isolation

Integration Service Environment (ISE) — Deprecated

ISE provided fully isolated, dedicated infrastructure. Microsoft is deprecating ISE in favour of Logic Apps Standard with VNet integration.

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Core Concepts

Workflows

A workflow is a series of steps that execute in sequence or in parallel. Each workflow has:

• A trigger — the event that starts the workflow
• Actions — the steps that execute after the trigger

Connectors

Connectors are pre-built integrations that connect to external services:

Category	Examples
Microsoft	Outlook, Teams, SharePoint, OneDrive, Dynamics 365
Cloud services	Azure Blob Storage, Cosmos DB, Service Bus, Event Grid
SaaS	Salesforce, Slack, Dropbox, Mailchimp, Jira, GitHub
Social	Twitter, Facebook
Enterprise	SAP, Oracle, IBM MQ
On-premises	SQL Server, File System, BizTalk (via data gateway)
Custom	Any REST API via HTTP connector or custom connectors

Each connector provides triggers and/or actions:

• Triggers — events that start a workflow (new email, new file, timer)
• Actions — operations performed in a workflow (send email, create record, call API)

Managed vs Built-in Connectors

• Built-in connectors — run natively in the Logic Apps runtime (HTTP, Schedule, Batch, Inline Code). No additional cost on Standard.
• Managed connectors — hosted by Microsoft, connect to external services. Divided into Standard (included) and Enterprise (premium pricing) connectors.

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Building a Workflow

Example: Order Processing Pipeline

Here is a complete workflow in the JSON-based Workflow Definition Language:

Scenario: When a new order arrives in a Service Bus queue, validate it, store it in Cosmos DB, send a confirmation email, and post a notification to Teams.

Workflow steps: