# webhooks

# Webhooks Study Guide

---

# What is a Webhook?

A webhook is:

# an automatic event notification sent from one system to another.

Instead of constantly asking:

> “Did something happen?”

the system:

# automatically pushes the event.

---

# Simple Explanation

Example:

```text id="w1"
Customer starts chat
      ↓
Glia sends webhook
      ↓
CRM automatically creates ticket
```

The webhook notifies another system:

# in real time.

---

# Webhook = Event-Driven Communication

Webhooks are commonly used for:

* notifications
* integrations
* automation
* workflow triggering

---

# Common Webhook Use Cases

| Event                | Webhook Action          |
| -------------------- | ----------------------- |
| Customer starts chat | Create CRM ticket       |
| Payment completed    | Send confirmation       |
| Call ended           | Update reporting system |
| Agent assigned       | Notify supervisor       |
| User authenticated   | Trigger workflow        |

---

# How Webhooks Work

# Step 1 — Event Occurs

Example:

```text id="w2"
Chat session started
```

---

# Step 2 — Source System Detects Event

Example:

* Glia
* CRM
* cloud platform

---

# Step 3 — Webhook Sent Automatically

Usually:

# HTTP POST request

Example:

```http id="w3"
POST /webhook/chat-started
```

---

# Step 4 — Receiving System Processes Event

Example:

```text id="w4"
CRM updates customer interaction history
```

---

# Example Webhook Payload

```json id="w5"
{
  "event": "chat_started",
  "customerId": "12345",
  "timestamp": "2026-05-20T15:30:00Z"
}
```

---

# Webhook Characteristics

| Characteristic    | Description              |
| ----------------- | ------------------------ |
| Event-driven      | Triggered automatically  |
| Push model        | Sends data automatically |
| Real-time         | Immediate notifications  |
| Usually HTTP POST | Most common method       |
| JSON payloads     | Common data format       |

---

# Webhooks vs APIs

# VERY IMPORTANT INTERVIEW TOPIC

| API                            | Webhook                               |
| ------------------------------ | ------------------------------------- |
| Request-based                  | Event-based                           |
| Client asks for data           | Server pushes data                    |
| Pull model                     | Push model                            |
| Requires polling               | Real-time notifications               |
| Client initiates communication | Source system initiates communication |

---

# Simple Analogy

# API

Like calling a restaurant:

> “Is my order ready?”

You continuously ask.

---

# Webhook

Like restaurant texting you:

> “Your order is ready.”

Automatic notification.

---

# API Example (Pull Model)

Client requests:

```http id="w6"
GET /api/chat/status
```

Client repeatedly checks status.

---

# Webhook Example (Push Model)

System automatically sends:

```http id="w7"
POST /webhook/chat-completed
```

No polling required.

---

# Why Webhooks Are Important

Webhooks improve:

* automation
* efficiency
* real-time workflows
* integrations
* scalability

VERY common in:

* CCaaS
* SaaS
* banking
* cloud systems

---

# Common Webhook Use Cases In Glia

Likely webhook events:

* chat started
* chat ended
* agent assigned
* authentication completed
* escalation triggered
* interaction transferred

---

# Common Webhook Troubleshooting

# Problem 1 — Webhook Not Received

Possible causes:

* incorrect URL
* firewall issue
* endpoint unavailable
* DNS issue

---

# Problem 2 — Authentication Failure

Webhook endpoint may require:

* API key
* bearer token
* OAuth authentication

Possible result:

```http id="w8"
401 Unauthorized
```

---

# Problem 3 — Invalid JSON Payload

Malformed JSON:

```json id="w9"
{
  "event": "chat_started"
  "customerId": "12345"
}
```

Missing comma causes failure.

---

# Problem 4 — Slow Endpoint Response

If receiving system responds slowly:

* webhook timeout
* retries may occur

---

# Problem 5 — SSL/TLS Issues

Webhook endpoints usually require:

# HTTPS/TLS

Problems:

* expired certificate
* invalid certificate
* TLS mismatch

---

# Webhook Troubleshooting Flow

# Step 1 — Validate Event Triggered

Did source system generate event?

Check:

* logs
* timestamps
* event history

---

# Step 2 — Validate Webhook URL

Check:

* DNS
* endpoint path
* HTTPS
* port access

---

# Step 3 — Validate Authentication

Check:

* bearer token
* API key
* OAuth credentials

---

# Step 4 — Validate Payload

Check:

* JSON syntax
* required fields
* data types

---

# Step 5 — Review HTTP Response Codes

| Code | Meaning                 |
| ---- | ----------------------- |
| 200  | Success                 |
| 401  | Authentication failed   |
| 403  | Permission denied       |
| 404  | Endpoint not found      |
| 500  | Receiving server failed |

---

# Step 6 — Review Logs

Check:

* webhook delivery logs
* API logs
* server logs
* timestamps

---

# Important Webhook Security Concepts

Because webhooks are inbound requests:
they should be protected with:

* HTTPS/TLS
* authentication
* validation
* IP restrictions if needed

---

# Common Interview Questions

# “What is a webhook?”

Good Answer:

> “A webhook is an event-driven mechanism where one system automatically sends data to another system when a specific event occurs.”

---

# “Difference between API and webhook?”

Good Answer:

> “APIs typically use a request/response pull model where a client requests data, while webhooks use an event-driven push model where the system automatically sends notifications when events occur.”

---

# “Why use webhooks instead of polling APIs?”

Good Answer:

> “Webhooks provide real-time event notifications and reduce unnecessary polling traffic, making integrations more efficient and responsive.”

---

# “How would you troubleshoot webhook failures?”

Good Answer:

> “I would validate the event trigger, confirm webhook URL connectivity, verify authentication and HTTPS/TLS configuration, review JSON payload formatting, analyze HTTP response codes, and check delivery logs.”

---

# Easy Memory Trick

# API = You Ask

# Webhook = System Tells You

Example:

```text id="w10"
API → pull
Webhook → push
```

---

# Important Terms To Know

| Term         | Meaning                     |
| ------------ | --------------------------- |
| API          | Request-based communication |
| Webhook      | Event-driven notification   |
| Polling      | Repeated API checking       |
| Push Model   | Automatic event delivery    |
| Pull Model   | Client requests data        |
| JSON Payload | Structured webhook data     |
| HTTPS/TLS    | Secure webhook transport    |
| Event-Driven | Trigger-based workflow      |