# User & Attributes

### Managing User Data

The `NetmeraUser` class allows you to send structured information about your application's users to Netmera. The ideal time to update user attributes is **right after the user logs into your application.**

{% hint style="warning" %}
**User ID Management**

For optimal performance and data integrity:

* **Update user information at login**: It’s crucial to update the user information as soon as the user logs in.
* **Unique userId**: Ensure that each user has a unique `userId`. Assigning the same `userId` to multiple users leads to data inconsistencies and is not recommended.
  {% endhint %}

### Updating User Information

After obtaining user information, set or update the user data by using the following example. You can update any attribute independent from the others.

{% tabs %}
{% tab title="Swift" %}

```swift
// Set user's properties
let user = NetmeraUser()
user.userId = "johnny.appleseed"
user.email = "johnny.appleseed@apple.com"
user.msisdn = "00905XXXXXXXXX"
user.name = "Johnny"
user.surname = "Appleseed"
user.language = NSLocale.preferredLanguages[0]

var birthComponents = DateComponents()
birthComponents.year = 1774
birthComponents.month = 9
birthComponents.day = 26
let calendar = Calendar(identifier: .gregorian)
user.dateOfBirth = calendar.date(from: birthComponents)

user.gender = NetmeraProfileAttributeGender.male
user.maritalStatus = NetmeraProfileAttributeMaritalStatus.married
user.numberOfChildren = 10
user.country = "United States"
user.state = "MA"
user.city = "Leominster"
user.district = "Leominster"
user.occupation = "Farmer"
user.industry = "Agriculture"
user.favouriteTeam = "FAVOURITE_TEAM"
user.externalSegments = ["segment1", "segment2"]

// Send data to Netmera
Netmera.update(user)
```

{% endtab %}

{% tab title="Objective-C" %}

```objectivec
// Set user's properties
NetmeraUser *user = [[NetmeraUser alloc] init];
user.userId = @"johnny.appleseed";
user.email = @"johnny.appleseed@apple.com";
user.MSISDN = @"00905XXXXXXXXX";
user.name = @"Johnny";
user.surname = @"Appleseed";
user.language = NSLocaleIdentifier;

NSDateComponents *birthComponents = [[NSDateComponents alloc] init];
birthComponents.year = 1774;
birthComponents.month = 9;
birthComponents.day = 26;

NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
user.dateOfBirth = [calendar dateFromComponents:birthComponents];

user.gender = NetmeraProfileAttributeGenderMale;
user.maritalStatus = NetmeraProfileAttributeMaritalStatusMarried;
user.numberOfChildren = 10;
user.country = @"United States";
user.state = @"MA";
user.city = @"Leominster";
user.district = @"Leominster";
user.occupation = @"Farmer";
user.industry = @"Agriculture";
user.favouriteTeam = @"FAVOURITE_TEAM";
user.externalSegments = @[@"segment1", @"segment2"];

// Send data to Netmera
[Netmera updateUser:user];
```

{% endtab %}
{% endtabs %}

### Removing Attributes <a href="#removing-attributes" id="removing-attributes"></a>

To remove a previously set attribute, assign `[NSNull null]` to the attribute in the user object.&#x20;

{% hint style="warning" %}
**UserId cannot be removed:**

**`userId` cannot be removed**, even if set to `null`.
{% endhint %}

{% tabs %}
{% tab title="Swift" %}

```swift
// This will remove previously set `email` value from Netmera
let user = NetmeraUser()
user.email = ""
Netmera.update(user)
```

{% endtab %}

{% tab title="Objective-C" %}

```objectivec
// This will remove previously set `email` value from Netmera
NetmeraUser *user = [[NetmeraUser alloc] init];
user.email = [NSNull null];
[Netmera updateUser:user];
```

{% endtab %}
{% endtabs %}

### Creating Custom Profile Attributes&#x20;

#### Step 1: Navigate to the Developers section

Custom profile attributes must be created and configured in the Netmera Panel before they can be used in the application.&#x20;

* Go to **Panel** > **Developers > Profile Attributes > Create New Attribute.**

#### Step 2: Fill in Attribute Details

Define the following information:

* **Name**: The unique identifier for the attribute.
* **Label**: A user-friendly name for the attribute.
* **Description**: A brief description of the attribute.
* **Data Type**: Choose the appropriate data type for the attribute.
* **Is Array**: Define whether the attribute can hold multiple values.

#### Step 3: Save the Attribute

After clicking **Save**, the custom attribute will be available for assignment to your users.

#### Step 4: Generated Code for Custom Attributes

Once the attribute is defined in the Netmera Panel, the generated code can be found at the bottom of the **Profile Attribute** page, under the **Generate Code** section. This code must be added to your Netmera Panel under **Profile Attributes > User Class**.

{% hint style="info" %}
**Private Information Considerations**

Under the **KVKK** law, the sharing of private user data is prohibited. To ensure compliance:

* **Private Information Flag**: When defining profile attributes or events, the **Private Information** feature must be selected to ensure that these attributes are not sent to the backend by the Netmera SDK.
* **SDK Enforcement**: The SDK checks for the **Private Information** flag during the `Netmera.updateUser(user:)` call. If the flag is set, the request will not be sent to the backend.
  {% endhint %}

<figure><img src="/files/QoRtHFanKtmtxa35m4Po" alt=""><figcaption></figcaption></figure>

### Fetch Coupon

The `fetchCoupon` method in Netmera allows you to retrieve and display the coupons earned by users in your iOS application. You can use the `NetmeraCouponFilter` to define the filtering criteria, such as the page number and the maximum number of coupons to retrieve.

1. Create a Filter: Use `NetmeraCouponFilter` to set the page number and the maximum number of coupons to retrieve.
2. Call the `fetchCoupon` Method: Pass the filter to the `fetchCoupon` method to fetch the coupons.
3. Handle the Result: Inside the closure, check if the coupons are fetched successfully. If so, assign them to the `coupons` property and reload the table view to display them.

```swift
let filter = NetmeraCouponFilter()
filter.page = Int32(pageSize)
filter.max = Int32(max)

Netmera.fetchCoupon(using: filter) { coupons, error in
    self.coupons = coupons ?? []
    self.tableView.reloadData()
}
```

### User Update Callback

The `User Update` feature calls the `update` function from the Netmera SDK, passing a `user` object as a parameter to update the user data. The function uses a closure (callback) to handle the result of the update. Depending on the success or failure of the update, a corresponding block is triggered.

{% hint style="info" %}

1. **Successful Update**: If the update is successful, the success block is triggered, and "success" is printed to the console.
2. **Error in Update**: If an error occurs during the update, the error block is triggered, and "error" is printed.
   {% endhint %}

{% tabs %}
{% tab title="Swift" %}

```swift
Netmera.update(user) { success, error in
    if success {
        print("success")
    } else {
        print("error")
    }
}
```

{% endtab %}

{% tab title="Objective-C" %}

```objectivec
[Netmera updateUser:user completion:^(BOOL isSuccess, NSError * _Nullable error) {
    if (isSuccess) {
        NSLog(@"Update user is success");
    } else {
        NSLog(@"%@", error);
    }
}];
```

{% endtab %}
{% endtabs %}

### Email Subscription Preferences

The Netmera SDK provides methods to manage email subscription preferences for your users.&#x20;

**1. Check Email Subscription Status**

Use the following method to check if the user has allowed email subscriptions:

```swift
Netmera.isAllowedEmailSubscription()
```

* **Returns**: A `Boolean` value (`true` if the user has allowed email subscriptions, otherwise `false`).

**2. Update Email Subscription Preferences**

Set the user's preference for email subscriptions using one of the methods below:

* **Allow Email Subscriptions**

  ```swift
  Netmera.setAllowedEmailSubscription(true)
  ```
* **Disallow Email Subscriptions**

  ```swift
  Netmera.setAllowedEmailSubscription(false)
  ```

These methods enable you to respect user preferences for email communications within your application.


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