Context configuration

In the client-side .NET SDK, you can construct a Context that only has a key by calling Context.New. The context kind defaults to “user,” or you can supply a different context kind. Alternatively, you can use Context.Builder, which allows setting all properties.

The argument to Builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

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Context context = Context.Builder("example-context-key")
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    .Set("firstName", "Sandy")
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    .Set("lastName", "Smith")
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    .Set("email", "sandy@example.com")
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    .Set("group", "microsoft")
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    .Build();

Here’s how to construct a context with a context kind of something other than “user”:

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var context = Context.New(ContextKind.Of("organization"), "example-organization-key");

Here’s how to construct a multi-context, which includes multiple context kinds:

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var userContext = Context.New("example-user-key");
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var orgContext = Context.New(ContextKind.Of("organization"), "example-organization-key");
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var multiContext = Context.NewMulti(userContext, orgContext);

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the .NET (client-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the .NET (client-side) SDK, read Anonymous contexts and users.

In the Android SDK, use a builder pattern to construct contexts. The argument to builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
LDContext context = LDContext.builder("example-context-key")
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    .set("email", "sandy@example.com")
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    .set("firstName", "Sandy")
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    .set("lastName", "Smith")
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    .set("group", "Global Health Services")
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    .build();

Here’s how to construct a context with a context kind of something other than “user”:

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LDContext context1 = LDContext.create(ContextKind.of("organization"), "example-organization-key");

Here’s how to construct a multi-context, which includes multiple context kinds:

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LDContext userContext = LDContext.create("example-user-key");
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LDContext deviceContext = LDContext.create(ContextKind.of("device"), "example-device-key");
3
4
LDContext multiContext = LDContext.createMulti(
5
    userContext,
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    deviceContext
7
);

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Android SDK, read Private attributes.

To learn how to configure anonymous contexts in the Android SDK, read Anonymous contexts and users.

In the C++ (client-side) SDK, you can construct a context using the ContextBuilder. The arguments to .Kind() are the context kind and key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key, an email address, or a hash for the key, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
auto context = ContextBuilder()
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  .Kind("user", "example-user-key")
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  .Set("firstName", "Sandy")
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  .Set("lastName", "Smith")
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  .Set("groups", {"Acme", "Global Health Services"})
6
  .Build();

Here’s how to construct a context with a context kind of something other than “user”:

1
auto context = ContextBuilder()
2
  .Kind("organization", "example-organization-key")
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  .Build();

Here’s how to construct a multi-context, which includes multiple context kinds:

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auto context = ContextBuilder()
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  .Kind("user", "example-user-key")
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  .Name("Sandy")
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  .Kind("organization", "example-organization-key")
5
  .Name("Global Health Services")
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  .Build();

To learn how to configure private attributes in the C++ (client-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the C++ (client-side) SDK, read Anonymous contexts and users.

Here’s an example of a user:

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const user = {
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  key: 'example-user-key',
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  firstName: 'Sandy',
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  lastName: 'Smith',
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  email: 'sandy@example.com',
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  custom: {
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    groups: ['Acme', 'Global Health Services']
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  }
9
};

The key property is the user’s key. The key should uniquely identify each user. You can use a primary key or a hash, as long as the same user always has the same key. We recommend using a hash if possible. In this example, the hash is "example-user-key".

To learn how to configure private attributes in the Electron SDK, read Private attributes.

To learn how to configure anonymous users in the Electron SDK, read Anonymous contexts and users.

In the Flutter SDK, use a builder pattern to construct contexts. The arguments to LDContextBuilder are the context’s kind and key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

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final context = LDContextBuilder()
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  .kind('user', 'example-user-key')
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  .setString('email', 'sandy@example.com')
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  .setString('firstName', 'Sandy')
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  .setString('lastName', 'Smith')
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  .setString('group', 'microsoft')
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  .build();

Here’s how to construct a context with a context kind of something other than “user”:

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final context = LDContextBuilder()
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  .kind('device', 'example-device-key')
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  .build();

Here’s how to construct a multi-context, which includes multiple context kinds:

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LDContextBuilder builder = LDContextBuilder();
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builder.kind('user', 'example-user-key')
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  .name('Sandy');
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builder.kind('organization', 'example-organization-key')
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  .name('Global Health Services');
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LDContext context = builder.build();

To learn how to configure private attributes in the Flutter SDK, read Private attributes.

To learn how to configure anonymous contexts in the Flutter SDK, read Anonymous contexts and users.

In the iOS SDK, you can construct a context using LDContextBuilder. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

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var contextBuilder = LDContextBuilder(key: "example-user-key")
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contextBuilder.trySetValue("name", .string("Sandy"))
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contextBuilder.trySetValue("email", .string("sandy@example.com"))
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let context = try? contextBuilder.build().get()

Here’s how to construct a context with a context kind of something other than “user”:

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var contextBuilder = LDContextBuilder(key: "example-organization-key")
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contextBuilder.kind("organization")
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let context = try? contextBuilder.build().get()

Here’s how to construct a multi-context, which includes multiple context kinds:

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var userBuilder = LDContextBuilder(key: "example-user-key")
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var deviceBuilder = LDContextBuilder(key: "example-device-key")
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deviceBuilder.kind("device")
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var multiBuilder = LDMultiContextBuilder()
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multiBuilder.addContext(try userBuilder.build().get())
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multiBuilder.addContext(try deviceBuilder.build().get())
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let context = try multiBuilder.build().get()

You can define additional attributes for a context by passing in a name and value for each. Additional attributes can be any JSON type, including boolean, number, string, array, or object.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn more about the specific context properties that are available in this SDK, read LDContextBuilder.

To learn how to configure private attributes in the iOS SDK, read Private attributes.

To learn how to configure anonymous contexts in the iOS SDK, read Anonymous contexts and users.

In the JavaScript SDK, construct a context using key/value pairs for the context attributes. Contexts use the LDContext type. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example of a context:

1
const context = {
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  kind: 'user',
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  key: 'example-user-key',
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  firstName: 'Sandy',
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  lastName: 'Smith',
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  email: 'sandy@example.com',
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  groups: ['Acme', 'Global Health Services']
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};

Here’s how to construct a context with a context kind of something other than “user”:

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const context = {
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  kind: 'organization',
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  key: 'example-organization-key'
4
};
5
const client = LDClient.initialize('example-client-side-id', context);
6
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try {
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  await client.waitForInitialization(5);
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  proceedWithSuccessfullyInitializedClient();
10
} catch(err) {
11
  // Client failed to initialized or timed out
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  // variation() calls return fallback values until initialization completes
13
}

Here’s how to construct a multi-context, which includes multiple context kinds:

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const deviceContext = {
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  kind: 'device',
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  type: 'iPad',
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  key: 'example-device-key'
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}
6
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const userContext = {
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  kind: 'user',
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  key: 'example-user-key',
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  name: 'Sandy',
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  role: 'doctor'
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}
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const multiContext = {
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  kind: 'multi',
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  user: userContext,
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  device: deviceContext
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}
19
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const client = LDClient.initialize('example-client-side-id', multiContext)
21
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try {
23
  await client.waitForInitialization(5);
24
  proceedWithSuccessfullyInitializedClient();
25
} catch(err) {
26
  // Client failed to initialized or timed out
27
  // variation() calls return fallback values until initialization completes
28
}

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the JavaScript SDK, read Private attributes.

To learn how to configure anonymous contexts in the JavaScript SDK, read Anonymous contexts and users.

In the Node.js (client-side) SDK, construct a context using key/value pairs for the context attributes. Contexts use the LDContext type. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example of a context:

1
const context = {
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  kind: 'user',
3
  key: 'example-user-key',
4
  firstName: 'Sandy',
5
  lastName: 'Smith',
6
  email: 'sandy@example.com',
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  groups: ['Acme', 'Global Health Services']
8
};

Here’s how to construct a context with a context kind of something other than “user”:

1
const context = {
2
  kind: 'organization',
3
  key: 'example-organization-key'
4
};

Here’s how to construct a multi-context, which includes multiple context kinds:

1
const deviceContext = {
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  kind: 'device',
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  type: 'iPad',
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  key: 'example-device-key'
5
}
6
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const userContext = {
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  kind: 'user',
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  key: 'example-user-key',
10
  name: 'Sandy',
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  role: 'doctor'
12
}
13
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const multiContext = {
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  kind: 'multi',
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  user: userContext,
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  device: deviceContext
18
}

The kind and name attributes expect string values. Other attribute values can be booleans, numbers, strings, arrays, or JSON objects.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Node.js (client-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the Node.js (client-side) SDK, read Anonymous contexts and users.

In the React Native SDK, construct a context using key/value pairs for the context attributes. Contexts use the LDContext type.

The first attribute in the object is the key. In the React Native SDK, both key and kind are required. They are the only mandatory attributes. The combination of key and kind must uniquely identify each context. You can use any value for the key, such as a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
import { type LDContext } '@launchdarkly/react-native-client-sdk';
2
3
// key and kind are the only required attributes
4
5
let context: LDContext = {
6
  key: 'example-user-key',
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  kind: 'user',
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  firstName: 'Sandy',
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  lastName: 'Smith',
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  email: 'sandy@example.com',
11
  address: {
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    street: '123 Main St',
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    city: 'Springfield'
14
  }
15
};

Here’s how to construct a context with a context kind of something other than “user”:

1
const context = {
2
  kind: 'organization',
3
  key: 'example-organization-key'
4
};

Here’s how to construct a multi-context, which includes multiple context kinds:

1
const deviceContext = {
2
  kind: 'device',
3
  key: 'example-device-key'
4
};
5
6
const userContext = {
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  kind: 'user',
8
  key: 'example-user-key',
9
  name: 'Sandy',
10
  role: 'doctor'
11
};
12
13
const multiContext = {
14
  kind: 'multi',
15
  user: userContext,
16
  device: deviceContext
17
}

If the context is anonymous, you should set the key to an empty string. The SDK will automatically set the key to a LaunchDarkly-specific, device-unique string that is consistent between app restarts and device reboots.

Other attributes can be booleans, numbers, strings, arrays, or JSON objects.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the React Native SDK, read Private attributes.

To learn how to configure anonymous contexts in the React Native SDK, read Anonymous contexts and users.

In the Roku SDK, use LaunchDarklyCreateContext to construct a context. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

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context = LaunchDarklyCreateContext({"key": "example-user-key", "kind": "user"})

Here’s how to construct a context with a context kind of something other than “user”:

1
context = LaunchDarklyCreateContext({"key": "example-organization-key", "kind": "organization"})

Here’s how to construct a multi-context, which includes multiple context kinds:

1
context = LaunchDarklyCreateContext({
2
    "kind": "multi",
3
    "user": { "key": "example-user-key", "name": "Sandy" },
4
    "org": { "key": "org-key-789xyz", "name": "LaunchDarkly" }
5
})

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Roku SDK, read Private attributes.

To learn how to configure anonymous contexts in the Roku SDK, read Anonymous contexts and users.

In the server-side .NET SDK, you can construct a Context that only has a key by calling Context.New. The context kind defaults to “user,” or you can supply a different context kind. Alternatively, you can use the Context.Builder method for building a context with other properties.

The argument to Builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
LDContext context = Context.Builder("example-context-key")
2
    .Set("firstName", "Sandy")
3
    .Set("lastName", "Smith")
4
    .Set("email", "sandy@example.com")
5
    .Set("groups", LdValue.ArrayOf(LdValue.Of("Acme"), LdValue.Of("Global Health Services")))
6
    .Build();

Here’s how to construct a context with a context kind of something other than “user”:

1
var context2 = Context.New(ContextKind.Of("organization"), "example-organization-key");

Here’s how to construct a multi-context, which includes multiple context kinds:

1
var userContext = Context.New("example-context-key");
2
3
var deviceContext = Context.Builder("example-device-key")
4
    .Kind("device")
5
    .Build();
6
7
var multiContext = Context.NewMulti(userContext, deviceContext);

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the .NET (server-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the .NET (server-side) SDK, read Anonymous contexts and users.

Here’s an example of a user:

1
LDUser user = new LDUser.Builder('example-user-key')
2
    .setFirstName('Sandy')
3
    .setLastName('Smith')
4
    .setEmail('sandy@example.com')
5
    .setCustom(new LDValueObject.Builder()
6
        .set('groups', new LDValueArray.Builder()
7
            .add(LDValue.of('Acme'))
8
            .add(LDValue.of('Global Health Services'))
9
            .build()
10
        )
11
        .build()
12
    )
13
    .build();

The argument to Builder is the user’s key. The key should uniquely identify each user. You can use a primary key or a hash, as long as the same user always has the same key. We recommend using a hash if possible. In this example, the hash is "example-user-key".

To learn how to configure private attributes in the Apex SDK, read Private attributes.

To learn how to configure anonymous users in the Apex SDK, read Anonymous contexts and users.

In the C++ (server-side) SDK, you can construct a context using the ContextBuilder. The arguments to .Kind() are the context kind and key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash for the key, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
auto context = ContextBuilder()
2
  .Kind("user", "example-user-key")
3
  .Set("firstName", "Sandy")
4
  .Set("lastName", "Smith")
5
  .Set("groups", {"Acme", "Global Health Services"})
6
  .Build();

Here’s how to construct a context with context kind of something other than “user”:

1
auto context = ContextBuilder()
2
  .Kind("organization", "example-organization-key")
3
  .Build();

Here’s how to construct a multi-context, which includes multiple context kinds:

1
auto context = ContextBuilder()
2
  .Kind("user", "example-user-key")
3
  .Name("Sandy")
4
  .Kind("organization", "example-organization-key")
5
  .Name("Global Health Services")
6
  .Build();

If you are working in C, when you are done with the context ensure that you free the structure:

1
LDContext_Free(context);

To learn how to configure private attributes in the C++ (server-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the C++ (server-side) SDK, read Anonymous contexts and users.

In the Erlang SDK, use ldclient_context:set and ldclient_context:new to define and construct a context.

The key property is the context’s key. The key is the only mandatory context attribute. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

You can set the kind, or, if you do not set it, LaunchDarkly assumes that the context kind is “user.”

Here’s an example of a context:

1
    Context = ldclient_context:set(<<"name">>, <<"Sandy Smith">>,
2
        ldclient_context:set(<<"email">>, <<"sandy@example.com">>,
3
        ldclient_context:set(<<"group">>, [<<"microsoft">>, <<"google">>],
4
        ldclient_context:new(<<"example-user-key">>, <<"user">>)))),

Here’s how to construct a context with a context kind of something other than “user”:

1
Context = ldclient_context:new(<<"example-organization-key">>, <<"organization">>)
2
%% Or as a map
3
Context = #{kind => <<"organization">>, key => <<"example-organization-key">>}

Here’s how to construct a multi-context, which includes multiple context kinds:

1
Context = ldclient_context:new_multi_from([
2
  %% Using `new/1` creates a context with a kind of <<"user">>.
3
  ldclient_context:new(<<"example-user-key">>),
4
  %% Using `new/2` creates a context of the specified kind (<<"device">>).
5
  ldclient_context:new(<<"example-device-key">>, <<"device">>)]). %% kind = device

To learn how to configure private attributes in the Erlang SDK, read Private attributes.

To learn how to configure anonymous contexts in the Erlang SDK, read Anonymous contexts and users.

In the Go SDK, you have two options for how you want to manage contexts:

• Create a context and pass it in when you initialize an LDScopedClient. This is a wrapper around LDClient that lets you specify the evaluation context to use for all operations. The scoped client’s context is a multi-context, and you can update the multi-context with additional associated contexts at any time.
• Create a context and pass it in to each method call, such as when you evaluate a flag. To use this option, create a single, shared instance of LDClient.

The Go SDK defines a Context struct and a Builder. The context key is the only mandatory context attribute. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
import (
2
    "github.com/launchdarkly/go-sdk-common/v3/ldcontext"
3
    "github.com/launchdarkly/go-sdk-common/v3/ldvalue"
4
)
5
6
// Context with only a key
7
// by default, the context kind is "user"
8
context1 := ldcontext.New("example-context-key")
9
10
// Context with a key plus other attributes
11
context2 := ldcontext.NewBuilder("context-key-456def").
12
    Kind("organization").
13
    Name("Global Health Services").
14
    SetString("email", "info@globalhealthexample.com").
15
    SetValue("address", ldvalue.ObjectBuild().
16
        SetString("street", "123 Main Street").
17
        SetString("city", "Springfield")).
18
    SetValue("groups", ldvalue.ArrayOf(
19
      ldvalue.String("Acme"), ldvalue.String("Global Health Services"))).
20
    Build()

Here’s how to construct a context with a context kind of something other than “user”:

1
context1 := ldcontext.NewWithKind("organization", "example-organization-key")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multiContext := ldcontext.NewMulti(
2
    ldcontext.New("example-user-key"),
3
    ldcontext.NewWithKind("device", "example-device-key")
4
)

You can also use the context builder to create each of the individual contexts:

1
multiContext := ldcontext.NewMulti(
2
    ldcontext.NewBuilder("example-user-key").Name("Sandy").Build(),
3
    ldcontext.NewBuilder("example-device-key").Kind("device").Name("iPad").Build(),
4
)

Each individual context within a multi-context can have the same attributes. The only restriction is that each context has to have a different context kind from the others within the multi-context.

If you’re working with LDScopedClient, you don’t need to manually create the multi-context. Instead, you can add new contexts to the scoped client’s multi-context as they become available, or update existing contexts:

1
userContext := ldcontext.New("example-user-key")
2
3
scopedClient := ld.NewScopedClient(client, userContext)
4
scopedClient.CurrentContext() // returns the single "user" context
5
6
scopedClient.AddContext(ldcontext.NewWithKind("device", "example-device-key"))
7
scopedClient.CurrentContext() // returns a multi-context with "user" and "device" contexts
8
9
scopedClient.BoolVariation("example-flag-key", false) // evaluates the flag using a multi-context with "user" and "device" contexts

After you create a scoped client, we recommend adding it your Go context. Another advantage of using LDScopedClient is that you can pass the scoped client to any logic that already takes a Go context (context.Context), using utility methods provided in the SDK. This means the scoped client is implicitly passed around through all of your code that uses context.Context, and you can access the scoped client anywhere in your application logic. To learn more, read Use Go contexts with LDScopedClient.

To learn more about the available LaunchDarkly context attributes, read Context and Builder.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Go SDK, read Private attributes.

To learn how to configure anonymous contexts in the Go SDK, read Anonymous contexts and users.

In the Haskell SDK, use makeContext to create a new context. The argument to makeContext is the context’s key. The key is the only mandatory attribute. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example of a context:

1
{-# LANGUAGE OverloadedStrings #-}
2
3
import LaunchDarkly.Server.Context
4
5
import Data.Function ((&))
6
7
-- Context with key and kind
8
context1 :: Context
9
context1 = makeContext "example-context-key" "user"
10
11
-- Context with a key plus other attributes
12
context2 :: Context
13
context2 = makeContext "context-key-456def" "organization"
14
    & withAttribute "name" "Global Health Services"
15
    & withAttribute "email" "info@globalhealthexample.com"
16
    & withAttribute "address" $ Object $ fromList [("street", "123 Main St"), ("city", "Springfield")]

Here’s how to construct a context with a context kind of something other than “user”:

1
makeContext "example-context-key" "organization"

Here’s how to construct a multi-context, which includes multiple context kinds:

1
makeMultiContext [ makeContext "example-user-key" "user"
2
                 , makeContext "example-device-key" "device"
3
                 ]

To learn how to configure private attributes in the Haskell SDK, read Private attributes.

To learn how to configure anonymous contexts in the Haskell SDK, read Anonymous contexts and users.

In the Java SDK, use a builder pattern to construct contexts. The argument to Builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
LDContext context = LDContext.builder("example-context-key")
2
  .set("firstName", "Sandy")
3
  .set("lastName", "Smith")
4
  .set("email", "sandy@example.com")
5
  .set("groups",
6
    LDValue.buildArray().add("Acme").add("Global Health Services").build())
7
  .build();

Here’s how to construct a context with a context kind of something other than “user”:

1
LDContext context1 = LDContext.create(ContextKind.of("organization"), "example-organization-key");

Here’s how to construct a multi-context, which includes multiple context kinds:

1
LDContext multiContext = LDContext.createMulti(
2
    LDContext.create("example-user-key"),
3
    LDContext.create(ContextKind.of("device"), "example-device-key")
4
);

The documentation for ContextBuilder shows you all the attributes that LaunchDarkly supports by default.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Java SDK, read Private attributes.

To learn how to configure anonymous contexts in the Java SDK, read Anonymous contexts and users.

In the Lua SDK, use makeContext to construct a context of any kind. This requires a context key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible. The context attributes are defined as part of the context kind.

To construct a user context specifically, you can use makeUser. Both makeUser and makeContext require a context key. You can omit the kind option if you construct your context with makeUser. This method is a convenience to make upgrading from the Lua SDK version 1.x to version 2.0 easier. It is deprecated and may be removed in future versions.

Here’s an example of a context:

1
-- using makeContext
2
local user1 = ld.makeContext({
3
    user = {
4
        key = "example-user-key-1",
5
        attributes = {
6
            firstName = "Sandy",
7
            lastName  = "Smith",
8
            email     = "sandy@example.com",
9
            groups    = { "Acme", "Global Health Services" }
10
        }
11
    }
12
})
13
14
-- using makeUser, which is deprecated,
15
-- to create an identical context (with unique key)
16
local user2 = ld.makeUser({
17
    key       = "example-user-key-2",
18
    firstName = "Sandy",
19
    lastName  = "Smith",
20
    email     = "sandy@example.com",
21
    custom    = {
22
        groups = { "Acme", "Global Health Services" }
23
    }
24
})
25
26
-- using makeContext to create a different kind of context
27
local orgContext = ld.makeContext({
28
    organization = {
29
      key = "example-organization-key",
30
      name = "Global Health Services"
31
    }
32
})

Here’s how to construct a context with a context kind of something other than “user”:

1
-- using makeContext to create a different kind of context
2
local orgContext = ld.makeContext({
3
    organization = {
4
      key = "example-organization-key",
5
      name = "Global Health Services"
6
    }
7
})

Here’s how to construct a multi-context, which includes multiple context kinds:

1
-- using makeContext to create a multi-context
2
local context = ld.makeContext({
3
    user = {
4
      key = "example-user-key"
5
    },
6
    org = {
7
      key = "example-organization-key"
8
    }
9
})

To learn more, read makeUser and makeContext.

To learn how to configure private attributes in the Lua SDK, read Private attributes.

To learn how to configure anonymous contexts in the Lua SDK, read Anonymous contexts and users.

In the Node.js (server-side) SDK, contexts are JSON objects. The key property is the context key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
const ld = require('@launchdarkly/node-server-sdk');
2
3
const context: ld.LDContext = {
4
  kind: 'user',
5
  key: 'example-user-key',
6
  firstName: 'Sandy',
7
  lastName: 'Smith',
8
  email: 'sandy@example.com',
9
  groups: ['Acme', 'Global Health Services'],
10
};

Here’s how to construct a context with a context kind of something other than “user”:

1
const context = {
2
   kind: 'device',
3
   key: 'example-device-key'
4
}

Here’s how to construct a multi-context, which includes multiple context kinds:

1
const context = {
2
  kind: 'multi',
3
  user: { key: 'example-user-key' },
4
  device: { key: 'example-device-key' }
5
}

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Node.js (server-side) SDK, read Private attributes.

To learn how to configure anonymous contexts in the Node.js (server-side) SDK, read Anonymous contexts and users.

In the PHP SDK, use a builder pattern to construct contexts. The first argument to LDContextBuilder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
$context = LDContext::builder("example-context-key")
2
    ->set("firstName", "Sandy")
3
    ->set("lastName", "Smith")
4
    ->set("email", "sandy@example.com")
5
    ->set("groups", ["Acme", "Global Health Services"])
6
    ->build();

Here’s how to construct a context with a context kind of something other than “user”:

1
$context = LDContext::create("example-context-key", "organization");

Here’s how to construct a multi-context, which includes multiple context kinds:

1
$deviceContext = LDContext::create("example-device-key", "device");
2
$orgContext = LDContext::create("example-organization-key", "org");
3
$multiContext = LDContext::createMulti($deviceContext, $orgContext);

To learn how to configure private attributes in the PHP SDK, read Private attributes.

To learn how to configure anonymous contexts in the PHP SDK, read Anonymous contexts and users.

In version 8.0 and higher of the Python SDK, the Context class has a create method for creating a context with a context kind of “user” and with only a key. It has a builder method for building a context with other properties.

The argument to Context.builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
context = Context.builder("example-context-key") \
2
    .set("firstName", "Sandy") \
3
    .set("lastName", "Smith") \
4
    .set("email", "sandy@example.com") \
5
    .set("groups", ["Acme", "Global Health Services"]) \
6
    .build()

Here’s how to construct a context with a context kind of something other than “user”:

1
context1 = Context.create("example-organization-key", "organization")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multi_context = Context.create_multi(
2
    Context.create("example-user-key"),
3
    Context.create("example-device-key", "device")
4
)

If you have many attributes to set, you can also create a context from a dictionary:

1
pre_existing_dict = {
2
    'key': 'example-context-key',
3
    'kind': 'user',
4
    'firstName': 'Sandy',
5
    'lastName': 'Smith',
6
    'email': 'sandy@example.com',
7
    'groups': ['Acme', 'Global Health Services'],
8
}
9
10
context = Context.from_dict(pre_existing_dict)

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn more, read from_dict.

To learn how to configure private attributes in the Python SDK, read Private attributes.

To learn how to configure anonymous contexts in the Python SDK, read Anonymous contexts and users.

In the Ruby SDK, contexts are instances of LaunchDarkly::LDContext. Legacy users can continue to be provided as simple hashes.

The key property is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key, an email address, or a hash string, as long as the same context always has the same key. We recommend using a hash string if possible.

Here’s an example:

1
context = LaunchDarkly::LDContext.create({
2
    key: "example-user-key",
3
    kind: "user",
4
    firstName: "Sandy",
5
    lastName: "Smith",
6
    email: "sandy@example.com",
7
    groups: ["Acme", "Global Health Services"]
8
})

Here’s how to construct a context with a context kind of something other than “user”:

1
context = LaunchDarkly::LDContext.with_key("example-context-key", "organization")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multi_context = LaunchDarkly::LDContext.create_multi([
2
    LaunchDarkly::LDContext.with_key("example-user-key"),
3
    LaunchDarkly::LDContext.with_key("example-device-key", "device"),
4
])

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Ruby SDK, read Private attributes.

To learn how to configure anonymous contexts in the Ruby SDK, read Anonymous contexts and users.

The Rust SDK defines a Context struct and a ContextBuilder.

The context key is the only mandatory context attribute. You can set the kind, or, if you do not set it, LaunchDarkly assumes that the context kind is “user.” The combination of key and kind must uniquely identify each context. For the key, you can use a primary key, a hash string, or some other value, as long as the same context always has the same key. We recommend using a hash string if possible.

Here’s an example:

1
// Context with only a key
2
let context = ContextBuilder::new("example-context-key").build()?;
3
4
// Context with a key plus other attributes
5
let context = ContextBuilder::new("example-context-key")
6
    .set_value("first_name", "Sandy".into())
7
    .set_value("last_name", "Smith".into())
8
    .set_value("email", "sandy@example.com".into())
9
    .set_value("groups", vec!["Acme", "Global Health Services"].into())
10
    .build();

Here’s how to construct a context with a context kind of something other than “user”:

1
let context = ContextBuilder::new("example-context-key")
2
    .kind("organization")
3
    .build()?;

Here’s how to construct a multi-context, which includes multiple context kinds:

1
let user_context = ContextBuilder::new("example-user-key").build()?;
2
client.identify(user_context.clone());
3
4
let device_context = ContextBuilder::new("example-device-key").kind("device").build()?;
5
client.identify(device_context.clone());
6
7
let multi_context = MultiContextBuilder::new()
8
.add_context(user_context)
9
.add_context(device_context)
10
.build()?;
11
12
client.identify(multi_context);

To learn more about the available attributes, read Context and ContextBuilder.

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

To learn how to configure private attributes in the Rust SDK, read Private attributes.

To learn how to configure anonymous contexts in the Rust SDK, read Anonymous contexts and users.

To configure contexts, the Akamai SDK uses the same code as the Node.js server-side SDK.

The Akamai SDK does not support sending events, so private attributes are not supported.

To configure contexts, the Cloudflare SDK uses the same code as the Node.js server-side SDK.

To configure contexts, the Fastly SDK uses the same code as the Node.js server-side SDK.

To configure contexts, the Vercel SDK uses the same code as the Node.js server-side SDK.

In the .NET AI SDK, you can construct a Context that only has a key by calling Context.New. The context kind defaults to “user,” or you can supply a different context kind. Alternatively, you can use the Context.Builder method for building a context with other properties.

The argument to Builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
LDContext context = Context.Builder("example-context-key")
2
    .Set("firstName", "Sandy")
3
    .Set("lastName", "Smith")
4
    .Set("email", "sandy@example.com")
5
    .Set("groups", LdValue.ArrayOf(LdValue.Of("Acme"), LdValue.Of("Global Health Services")))
6
    .Build();

Here’s how to construct a context with a context kind of something other than “user”:

1
var context2 = Context.New(ContextKind.Of("organization"), "example-organization-key");

Here’s how to construct a multi-context, which includes multiple context kinds:

1
var userContext = Context.New("example-context-key");
2
3
var deviceContext = Context.Builder("example-device-key")
4
    .Kind("device")
5
    .Build();
6
7
var multiContext = Context.NewMulti(userContext, deviceContext);

If an attribute is a JSON object, then in your config targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting rules. You can use . as a delimiter in your config message. Continuing the same example, you could use {{ldctx.address.city}} in your message, and the value of the “city” field will be substituted when you customize the config. To learn more, read Target with flags and Customizing configs.

To learn how to configure private attributes in the .NET AI SDK, read Private attributes.

To learn how to configure anonymous contexts in the .NET AI SDK, read Anonymous contexts and users.

The Go AI SDK defines a Context struct and a Builder. The context key is the only mandatory context attribute. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
import (
2
    "github.com/launchdarkly/go-sdk-common/v3/ldcontext"
3
    "github.com/launchdarkly/go-sdk-common/v3/ldvalue"
4
)
5
6
// Context with only a key
7
// by default, the context kind is "user"
8
context1 := ldcontext.New("example-context-key")
9
10
// Context with a key plus other attributes
11
context2 := ldcontext.NewBuilder("context-key-456def").
12
    Kind("organization").
13
    Name("Global Health Services").
14
    SetString("email", "info@globalhealthexample.com").
15
    SetValue("address", ldvalue.ObjectBuild().
16
        SetString("street", "123 Main Street").
17
        SetString("city", "Springfield")).
18
    SetValue("groups", ldvalue.ArrayOf(
19
      ldvalue.String("Acme"), ldvalue.String("Global Health Services"))).
20
    Build()

Here’s how to construct a context with a context kind of something other than “user”:

1
context1 := ldcontext.NewWithKind("organization", "example-organization-key")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multiContext := ldcontext.NewMulti(
2
    ldcontext.New("example-user-key"),
3
    ldcontext.NewWithKind("device", "example-device-key")
4
)

Each individual context within a multi-context can have the same attributes. The only restriction is that each context has to have a different context kind from the others within the multi-context.

You can also use the context builder to create each of the individual contexts:

1
multiContext := ldcontext.NewMulti(
2
    ldcontext.NewBuilder("example-user-key").Name("Sandy").Build(),
3
    ldcontext.NewBuilder("example-device-key").Kind("device").Name("iPad").Build(),
4
)

If an attribute is a JSON object, then in your config targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting rules. You can use . as a delimiter in your config message. Continuing the same example, you could use {{ldctx.address.city}} in your message, and the value of the “city” field will be substituted when you customize the config. To learn more, read Target with flags and Customizing configs.

To learn how to configure private attributes in the Go AI SDK, read Private attributes.

To learn how to configure anonymous contexts in the Go AI SDK, read Anonymous contexts and users.

In the Node.js (server-side) AI SDK, contexts are JSON objects. The key property is the context key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
const context: LDContext = {
2
  kind: 'user',
3
  key: 'example-user-key',
4
  firstName: 'Sandy',
5
  lastName: 'Smith',
6
  email: 'sandy@example.com',
7
  groups: ['Acme', 'Global Health Services'],
8
};

Here’s how to construct a context with a context kind of something other than “user”:

1
const context: LDContext = {
2
   kind: 'device',
3
   key: 'example-device-key'
4
}

Here’s how to construct a multi-context, which includes multiple context kinds:

1
const context: LDContext = {
2
  kind: 'multi',
3
  user: { key: 'example-user-key' },
4
  device: { key: 'example-device-key' }
5
}

If an attribute is a JSON object, then in your config targeting, you can use / as a delimiter to refer to specific fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting rules. You can use . as a delimiter in your config message. Continuing the same example, you could use {{ldctx.address.city}} in your message, and the value of the “city” field will be substituted when you customize the config. To learn more, read Target with configs and Customizing configs.

To learn how to configure private attributes in the Node.js (server-side) AI SDK, read Private attributes.

To learn how to configure anonymous contexts in the Node.js (server-side) AI SDK, read Anonymous contexts and users.

In the Python AI SDK, the Context class has a create method for creating a context with a context kind of “user” and with only a key. It has a builder method for building a context with other properties.

The argument to Context.builder is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key or a hash, as long as the same context always has the same key. We recommend using a hash if possible.

Here’s an example:

1
context = Context.builder("example-context-key") \
2
    .set("firstName", "Sandy") \
3
    .set("lastName", "Smith") \
4
    .set("email", "sandy@example.com") \
5
    .set("groups", ["Acme", "Global Health Services"]) \
6
    .build()

Here’s how to construct a context with a context kind of something other than “user”:

1
context1 = Context.create("example-organization-key", "organization")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multi_context = Context.create_multi(
2
    Context.create("example-user-key"),
3
    Context.create("example-device-key", "device")
4
)

If you have many attributes to set, you can also create a context from a dictionary:

1
pre_existing_dict = {
2
    'key': 'example-context-key',
3
    'kind': 'user',
4
    'firstName': 'Sandy',
5
    'lastName': 'Smith',
6
    'email': 'sandy@example.com',
7
    'groups': ['Acme', 'Global Health Services'],
8
}
9
10
context = Context.from_dict(pre_existing_dict)

If an attribute is a JSON object, then in your config targeting, you can use / as a delimiter to refer to specific fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting rules. You can use . as a delimiter in your config message. Continuing the same example, you could use {{LDCTX.address.city}} in your message, and the value of the “city” field will be substituted when you customize the config. To learn more, read Target with configs and Customizing configs.

To learn how to configure private attributes in the Python AI SDK, read Private attributes.

To learn how to configure anonymous contexts in the Python AI SDK, read Anonymous contexts and users.

In the Ruby AI SDK, contexts are instances of LaunchDarkly::LDContext.

The key property is the context’s key. The combination of key and kind must uniquely identify each context. For the key, you can use a primary key, an email address, or a hash string, as long as the same context always has the same key. We recommend using a hash string if possible.

Here’s an example:

1
context = LaunchDarkly::LDContext.create({
2
    key: "example-user-key",
3
    kind: "user",
4
    firstName: "Sandy",
5
    lastName: "Smith",
6
    email: "sandy@example.com",
7
    groups: ["Acme", "Global Health Services"]
8
})

Here’s how to construct a context with a context kind of something other than “user”:

1
context = LaunchDarkly::LDContext.with_key("example-context-key", "organization")

Here’s how to construct a multi-context, which includes multiple context kinds:

1
multi_context = LaunchDarkly::LDContext.create_multi([
2
    LaunchDarkly::LDContext.with_key("example-user-key"),
3
    LaunchDarkly::LDContext.with_key("example-device-key", "device"),
4
])

If an attribute is a JSON object, then in your flag or segment targeting, you can use / as a delimiter to refer to specific object fields. For example, if you have an “address” attribute that includes several fields, then you could use /address/city in your targeting. To learn more, read Target with flags.

You can use . as a delimiter in your config message. Continuing the same example, you could use {{LDCTX.address.city}} in your message, and the value of the “city” field will be substituted when you customize the config. To learn more, read Target with configs and Customizing configs.

To learn how to configure private attributes in the Ruby AI SDK, read Private attributes.

To learn how to configure anonymous contexts in the Ruby AI SDK, read Anonymous contexts and users.