Bridges

Link a page or an object of your app (an article, a product, a recipe…) to a community post that Octopus creates for it, so your users can discuss it and jump back to it from the community.

Android availableiOS availableFlutter ≥ 1.12.0React Native ≥ 1.13.0Unity ≥ 1.13.0

Before you begin

• Complete the Quickstart: the SDK is initialized and the community UI opens.
• Give each object you want to link a stable, unique id. The SDK uses it to find the post again, and hands it back to you when a user taps the post's button.
• If your community requires signed bridge posts, add a signing route to your backend: see Generate fingerprint for bridge and Generate token for bridge.
• To label the post with a group, get the group id from the group list.

How it works

A bridge is a post that belongs to one of your objects:

1. Your app describes the object: its id, the text of the post, and optionally an image, a catchphrase, a button label and a group.
2. The SDK fetches the post linked to this id. The first time, it creates the post from your description and asks your token provider for a signature. Later calls return the existing post unchanged: the description is only used at creation.
3. The SDK returns the post, with its Octopus post id. Open the Octopus UI on this post id to show it.
4. When a user taps the post's button in the community, the SDK calls your callback with the object id, and your app opens the matching content.
5. Optionally, your app observes the post to show its reaction, comment and view counts in its own UI, and sets the user's reaction from there.

---

1. Prepare the post content

Describe the object and the post to create for it. Only the object id and the text are required.

Field	Required	Constraint
Object id	Yes	Stable and unique for your object.
Text	Yes	Between 10 and 5000 characters.
Catchphrase	No	Shown in bold below the text, for example "What do you think about this?". Fewer than 84 characters; 6 to 38 recommended.
Button text	No	Label of the button that opens your object, for example "Read the article" or "Buy it". Fewer than 28 characters; 4 to 28 recommended. Without it, or without the callback of step 3, no button is shown.
Group id	No	The group the post is labelled with. Without it, the group follows your community settings.
Image	No	A local image or a remote URL, within the image constraints below.

The image must meet these constraints:

Constraint	Value
File size	Less than 50 MB
Format	JPG or PNG
Side length	Between 50 px and 4000 px
Aspect ratio	At most 32:9 (longer side divided by shorter side)
Remote image	A public URL that points at the image file itself

Android

• ClientPost(objectId, text, attachment, catchPhrase, viewObjectButtonText, groupId) — only objectId and text are required.
• attachment: Resource? — Resource.Remote(url) for a remote image, Resource.Local(uri) for a local one.

val clientPost = ClientPost(
    objectId = "recipe-129302938", // A unique identifier for your content
    text = "The perfect Canelés", // Between 10 and 5000 chars
    attachment = Resource.Remote(url = imageUrl), // or Resource.Local(uri)
    groupId = foodRecipeGroupId, // The id of the Octopus group. Null if default.
    catchPhrase = "Tried the canelés? Tell us how good they were!", // Less than 84 characters
    viewObjectButtonText = "Read the recipe" // Less than 28 characters
)

iOS

• ClientPost(clientObjectId:groupId:text:catchPhrase:attachment:viewClientObjectButtonText:) — groupId and catchPhrase can be omitted; pass nil for attachment or viewClientObjectButtonText to leave them out.
• attachment: Attachment? — .distantImage(url) for a remote image, .localImage(data) for a local one.

let clientPost = ClientPost(
    clientObjectId: "recipe-129302938", // A unique identifier for your content
    groupId: foodRecipeGroupId, // The id of the Octopus group. Nil if default.
    text: "The perfect Canelés", // Between 10 and 5000 chars
    catchPhrase: "Tried the canelés? Tell us how good they were!", // Less than 84 characters
    attachment: .distantImage(imageUrl), // or .localImage(data)
    viewClientObjectButtonText: "Read the recipe" // Less than 28 characters
)

Flutter

• ClientPost(objectId:, text:, attachment:, catchPhrase:, viewObjectButtonText:, groupId:) — only objectId and text are required.
• attachment: OctopusClientPostAttachment? — OctopusRemoteImageAttachment(uri) for a remote image, OctopusLocalImageAttachment(bytes) for image bytes you already hold.

final clientPost = ClientPost(
  objectId: "recipe-129302938", // A unique identifier for your content
  text: "The perfect Canelés", // Between 10 and 5000 chars
  attachment: OctopusRemoteImageAttachment(Uri.parse(imageUrl)), // or OctopusLocalImageAttachment(bytes)
  groupId: foodRecipeGroupId, // The id of the Octopus group. Null if default.
  catchPhrase: "Tried the canelés? Tell us how good they were!", // Less than 84 characters
  viewObjectButtonText: "Read the recipe", // Less than 28 characters
);

React Native

• ClientPost — an object with objectId and text required, and attachment, catchPhrase, viewObjectButtonText, groupId optional.
• attachment: OctopusClientPostAttachment — { type: 'remoteImage', url } for a remote image, { type: 'localImage', uri } for a file:// URI or the name of an image bundled with the app.

import type { ClientPost } from '@octopus-community/react-native';

const clientPost: ClientPost = {
  objectId: 'recipe-129302938', // A unique identifier for your content
  text: 'The perfect Canelés', // Between 10 and 5000 chars
  attachment: { type: 'remoteImage', url: imageUrl }, // or { type: 'localImage', uri }
  groupId: foodRecipeGroupId, // The id of the Octopus group. Omit if default.
  catchPhrase: 'Tried the canelés? Tell us how good they were!', // Less than 84 characters
  viewObjectButtonText: 'Read the recipe', // Less than 28 characters
};

Unity

• OctopusClientObject — set ObjectId and Text; CatchPhrase, ViewObjectButtonText, GroupId and SignBridgeShare are optional.
• ImageUrl for a remote image (an absolute HTTP(S) URL), ImagePath for a local file. Set at most one.

var clientObject = new OctopusClientObject
{
    ObjectId = "recipe-129302938", // A unique identifier for your content
    Text = "The perfect Canelés", // Between 10 and 5000 chars
    ImageUrl = imageUrl, // or ImagePath = localImagePath
    GroupId = foodRecipeGroupId, // The id of the Octopus group. Null if default.
    CatchPhrase = "Tried the canelés? Tell us how good they were!", // Less than 84 characters
    ViewObjectButtonText = "Read the recipe" // Less than 28 characters
};

---

2. Get or create the post

Pass the content to the SDK. It returns the post linked to the object id, and creates it the first time. An existing post is returned as is: changing the content afterwards does not update it.

When the SDK creates a post, it calls your token provider with a bridge fingerprint and waits for a signature. For the best security, ignore this fingerprint: compute it on your backend from your own copy of the content (see Generate fingerprint for bridge). Otherwise, send the fingerprint to your backend. In both cases, your backend signs it (see Generate token for bridge). If your community does not require a signature, return no token.

warning

Avoid repeatedly deleting and recreating a bridge post for the same content id. Recreating a post starts a brand-new bridge: its comments, reactions and engagement counters all reset to zero. On top of that, each content id only supports a limited number of delete-and-recreate cycles; past that limit, creating a new post for that content will fail. Treat deletion as occasional, not as part of a regular publishing loop.

Android

• clientPost: ClientPost — the content from step 1.
• tokenProvider: (suspend (String) -> String?)? — receives the bridge fingerprint and returns the signature, or null when your community does not require one.
• Returns OctopusResult<OctopusPost, ClientPostError>; the function is suspend.

val result = OctopusSDK.fetchOrCreateClientObjectRelatedPost(
    clientPost = clientPost,
    tokenProvider = { bridgeFingerprint ->
        // `server` represents your own backend client — replace with your actual implementation.
        // Return null if your community does not require a signature.
        server.getBridgeSignature(bridgeFingerprint)
    }
)
when (result) {
    is OctopusResult.Success -> {
        val postId = result.data.id // Octopus post id, used in steps 4 and 6
    }
    is OctopusResult.Failure -> {
        // Invalid content (ClientPostError), no network, user not authenticated…
    }
}

iOS

• content: ClientPost — the content from step 1.
• tokenProvider: (String) async throws -> String? — receives the bridge fingerprint and returns the signature, or nil when your community does not require one.
• Returns any OctopusPost; the function is async throws(ClientPostError).

do {
    let post = try await octopus.fetchOrCreateClientObjectRelatedPost(
        content: clientPost,
        tokenProvider: { bridgeFingerprint in
            // `server` represents your own backend client — replace with your actual implementation.
            // Return nil if your community does not require a signature.
            return try await server.getBridgeSignature(bridgeFingerprint: bridgeFingerprint)
        }
    )
    let postId = post.id // Octopus post id, used in steps 4 and 6
} catch {
    // error: ClientPostError — invalid content, no network, user not authenticated…
}

Flutter

• clientPost: ClientPost — the content from step 1.
• tokenProvider: Future<String?> Function(String)? — receives the bridge fingerprint and returns the signature, or null. Omit it when your community does not require a signature.
• Returns Future<OctopusResult<OctopusPost, ClientPostError>>.

final octopus = OctopusSDK();

final result = await octopus.fetchOrCreateClientObjectRelatedPost(
  clientPost,
  tokenProvider: (bridgeFingerprint) async {
    // `server` represents your own backend client — replace with your actual implementation.
    // Return null if your community does not require a signature.
    return server.getBridgeSignature(bridgeFingerprint);
  },
);

switch (result) {
  case OctopusSuccess(:final data):
    final postId = data.id; // Octopus post id, used in steps 4 and 6
  case OctopusInvalidArguments<OctopusServerError>(:final errors):
    // Invalid content. Naming `<OctopusServerError>` keeps the switch exhaustive.
    for (final error in errors.whereType<ClientPostError>()) {
      debugPrint(error.errorMessage);
    }
  case OctopusConnectionFailure():
    // No network, user not authenticated…
}

React Native

• clientPost: ClientPost — the content from step 1.
• Returns Promise<OctopusPost>; a failure rejects with an error you can test with isClientPostError.
• The token provider is not an argument: register it once with useBridgeShareTokenProvider (a hook) or addBridgeShareTokenRequestListener (a plain function). It receives the bridge fingerprint and returns the signature, or null.

import {
  fetchOrCreateClientObjectRelatedPost,
  isClientPostError,
  useBridgeShareTokenProvider,
} from '@octopus-community/react-native';

// Register once, in a component mounted for the app's lifetime.
useBridgeShareTokenProvider(async (bridgeFingerprint) => {
  // `server` represents your own backend client — replace with your actual implementation.
  // Return null if your community does not require a signature.
  return server.getBridgeSignature(bridgeFingerprint);
});

try {
  const post = await fetchOrCreateClientObjectRelatedPost(clientPost);
  const postId = post.id; // Octopus post id, used in steps 4 and 6
} catch (error) {
  if (isClientPostError(error)) {
    console.warn(`${error.code}: ${error.message}`); // Invalid content, no network…
  }
}

info

The same registered provider also signs the images of the create-post editor, described in Sign a Bridge Share image: register it once and it serves both.

Unity

• clientObject: OctopusClientObject — the content from step 1. Set its SignBridgeShare to provide the signature: it receives the bridge fingerprint and returns the token. Leave it null when your community does not require one.
• onResult: Action<string> — receives the Octopus post id.
• onError: Action<OctopusClientPostError> — inspect Code and Message.

clientObject.SignBridgeShare = async bridgeFingerprint =>
{
    // `Http` is a System.Net.Http.HttpClient; replace the URL with your backend signing route.
    return await Http.GetStringAsync(
        "https://your-backend.example/generateBridgeSignature?fingerprint=" +
        System.Uri.EscapeDataString(bridgeFingerprint)).ConfigureAwait(false);
};
OctopusSDK.FetchOrCreateClientObjectRelatedPost(clientObject,
    onResult: postId => { /* Octopus post id, used in steps 4 and 6 */ },
    onError: error => { /* Invalid content, no network… see error.Code and error.Message */ });

warning

SignBridgeShare runs off the Unity player loop: use loop-independent I/O such as System.Net.Http, not UnityWebRequest. Throwing or returning an empty token fails the request. onResult and onError run on the Unity main thread.

---

3. Handle taps on the content button

Register a callback to open your object when a user taps the post's button in the community. The SDK passes the object id you gave in step 1. Register it before opening the Octopus UI: without a callback, the button is not shown.

Android

• onNavigateToClientObject: (String) -> Unit — a parameter of octopusComposables, called with the object id.

// In your NavHost setup
octopusComposables(
    // ...
    onNavigateToClientObject = { objectId ->
        // Display the content that has the given objectId
    }
)

iOS

• set(displayClientObjectCallback:) — called with the object id.

octopus.set(displayClientObjectCallback: { objectId in
    // Display the content that has the given objectId
})

Flutter

• OctopusSDK.setNavigateToClientObjectCallback(callback) — called with the object id. Returns a function that unregisters the callback. Registering again replaces the previous callback.

// Register early, for example in initState
final cancel = OctopusSDK.setNavigateToClientObjectCallback((objectId) {
  // Display the content that has the given objectId
});

// Later, in dispose
cancel();

React Native

• setNavigateToClientObjectCallback(callback) — called with the object id. Returns a function that unregisters the callback; it only removes its own registration.

import { setNavigateToClientObjectCallback } from '@octopus-community/react-native';

// Register once, at app start
useEffect(() => {
  return setNavigateToClientObjectCallback((objectId) => {
    // Display the content that has the given objectId
  });
}, []);

info

Keep the callback registered while the Octopus UI is on screen. On Android, a late registration leaves the button hidden until the UI is reopened. On iOS, the button stays visible after you unregister, and its taps do nothing.

Unity

• OctopusSDK.OnNavigateToClientObject: Action<string> — a static event raised with the object id.

public class ClientObjectHandler : MonoBehaviour
{
    void Start() => OctopusSDK.OnNavigateToClientObject += OnNavigateToClientObject;

    void OnDestroy() => OctopusSDK.OnNavigateToClientObject -= OnNavigateToClientObject;

    void OnNavigateToClientObject(string objectId)
    {
        // Display the content that has the given objectId
    }
}

---

4. Display the post

Open the Octopus UI on the post id returned in step 2, for example when the user taps a "Discuss" button on your object page. See Open a specific screen for the other entry points of each platform.

Android

• OctopusPostDetailsContent(navController, postId, …) — the post detail screen as a composable.

OctopusPostDetailsContent(
    navController = navController,
    postId = postId,
    modifier = Modifier.fillMaxSize(),
    // ...
)

iOS

• initialScreen: .post(.init(postId:)) — opens OctopusHomeScreen on the post.

OctopusHomeScreen(octopus: octopus, initialScreen: .post(.init(postId: postId)))

Flutter

• initialScreen: OctopusInitialScreen.post(PostScreenInfo(postId:)) — opens OctopusHomeScreen on the post. The OctopusPostDetailsScreen(postId:) widget shows the post alone.

OctopusHomeScreen(
  initialScreen: OctopusInitialScreen.post(PostScreenInfo(postId: postId)),
)

React Native

• openUI({ initialScreen: { type: 'post', postId } }) — opens the Octopus UI on the post.

import { openUI } from '@octopus-community/react-native';

await openUI({ initialScreen: { type: 'post', postId } });

Unity

• OctopusSDK.OpenPost(postId, navigationMode) — opens the Octopus UI on the post. navigationMode is optional; it picks the iOS navigation container and is ignored on Android. An empty postId opens the main feed.

OctopusSDK.OpenPost(postId);

---

5. Show live post data

Observe the post linked to an object to show its reaction, comment and view counts in your own UI, along with the current user's reaction. The observation emits the latest state of the post, and nothing (or an empty value) until the post exists.

The post carries:

Field	Meaning
Id	The Octopus post id.
Reactions	One entry per reaction kind, with its count.
Comment count	Number of comments.
View count	Number of views.
User reaction	The current user's reaction, or empty when the user has not reacted.

Android

• OctopusSDK.getClientObjectRelatedPostFlow(clientObjectId): Flow<OctopusPost?> — emits null until the post exists.
• OctopusPost: id, reactions: List<OctopusReactionCount> (each with reactionKind and count), commentCount, viewCount, userReactionKind.

OctopusSDK.getClientObjectRelatedPostFlow(clientObjectId = "recipe-129302938")
    .filterNotNull()
    .collect { post ->
        val reactions = post.reactions
        val commentCount = post.commentCount
        val viewCount = post.viewCount
        val userReaction = post.userReactionKind // null if the user has not reacted
    }

iOS

• octopus.getClientObjectRelatedPostPublisher(clientObjectId:) — an AnyPublisher<(any OctopusPost)?, Never> that emits nil until the post exists.
• OctopusPost: id, reactions: [OctopusReactionCount], commentCount, viewCount, userReaction.

octopus.getClientObjectRelatedPostPublisher(clientObjectId: "recipe-129302938")
    .compactMap { $0 }
    .sink { post in
        let reactions = post.reactions
        let commentCount = post.commentCount
        let viewCount = post.viewCount
        let userReaction = post.userReaction // nil if the user has not reacted
    }
    .store(in: &cancellables)

Flutter

• OctopusSDK.getClientObjectRelatedPostFlow(clientObjectId): Stream<OctopusPost?> — emits null until the post exists. Each subscription runs its own observation; cancel it to stop.
• OctopusPost: id, reactions: List<OctopusReactionCount> (each with reactionKind and count), commentCount, viewCount, userReactionKind.

final subscription = OctopusSDK.getClientObjectRelatedPostFlow("recipe-129302938")
    .where((post) => post != null)
    .listen((post) {
      final reactions = post!.reactions;
      final commentCount = formatOctopusCompactCount(post.commentCount);
      final viewCount = formatOctopusCompactCount(post.viewCount);
      final userReaction = post.userReactionKind; // null if the user has not reacted
    });

tip

formatOctopusCompactCount(count, {locale}) renders a count in the same compact K / M / B style as the community UI.

React Native

• addClientObjectRelatedPostListener(clientObjectId, callback) — calls callback with the post, or null until the post exists. Returns a subscription; each call runs its own observation, and remove() stops only that one.
• OctopusPost: id, reactions (each with reactionKind and count), commentCount, viewCount, userReactionKind.

import { addClientObjectRelatedPostListener, formatOctopusCompactCount } from '@octopus-community/react-native';

useEffect(() => {
  const subscription = addClientObjectRelatedPostListener('recipe-129302938', (post) => {
    if (!post) return; // No post created yet for this object
    const reactions = post.reactions;
    const commentCount = formatOctopusCompactCount(post.commentCount);
    const viewCount = formatOctopusCompactCount(post.viewCount);
    const userReaction = post.userReactionKind; // null if the user has not reacted
  });
  return () => subscription.remove();
}, []);

tip

formatOctopusCompactCount(count, { locale }) renders a count in the same compact K / M / B style as the community UI. Pass the locale you gave to overrideDefaultLocale so both match.

Unity

• OctopusSDK.StartObservingClientObjectRelatedPost(objectId) / StopObservingClientObjectRelatedPost(objectId) — one observation per object id; a repeated start does nothing.
• OctopusSDK.OnClientObjectRelatedPostChanged: Action<string, OctopusPost> — raised on the Unity main thread with the object id and its post, or null until the post exists. Subscribe before you start the observation.
• OctopusPost: Id, Reactions (each with ReactionKind and Count), CommentCount, ViewCount, UserReactionKind.

System.Action<string, OctopusPost> onPost = (objectId, post) =>
{
    if (objectId != "recipe-129302938" || post == null) return;
    var reactions = post.Reactions;
    string commentCount = OctopusSDK.FormatOctopusCompactCount(post.CommentCount);
    string viewCount = OctopusSDK.FormatOctopusCompactCount(post.ViewCount);
    OctopusReactionKind? userReaction = post.UserReactionKind; // null if the user has not reacted
};
OctopusSDK.OnClientObjectRelatedPostChanged += onPost;
OctopusSDK.StartObservingClientObjectRelatedPost("recipe-129302938");

// Later, to stop observing
OctopusSDK.StopObservingClientObjectRelatedPost("recipe-129302938");
OctopusSDK.OnClientObjectRelatedPostChanged -= onPost;

tip

OctopusSDK.FormatOctopusCompactCount(count) renders a count in the compact K / M / B style, with a dot as decimal separator. Initialization, a community switch, reset and stop cancel the observations: start them again afterwards.

---

6. Set a reaction from your UI

Android ≥ 1.12.0iOS ≥ 1.12.0Flutter ≥ 1.12.0React Native ≥ 1.13.0Unity ≥ 1.13.0

Let users react to the post without opening the community. Pass a reaction kind to set the user's reaction, or an empty value to remove it. Setting the same reaction twice has no further effect.

The call takes the Octopus post id returned in step 2 or read from the observed post, not your object id. It works on any post, bridge or not.

The reaction kinds are heart ❤️, joy 😂, mouthOpen 😮, clap 👏, cry 😢 and rage 😡.

Android

• reaction: OctopusReactionKind? — OctopusReactionKind.Heart, Joy, MouthOpen, Clap, Cry or Rage; null removes the reaction.
• postId: String — the Octopus post id.
• Returns OctopusResult<Unit, SetReactionError>; the function is suspend.

// Set a reaction; pass reaction = null to remove it
when (val result = OctopusSDK.setReaction(reaction = OctopusReactionKind.Heart, postId = postId)) {
    is OctopusResult.Success -> {
        // Reaction updated
    }
    is OctopusResult.Failure -> {
        // SetReactionError (UnknownReaction, PostNotFound, ReactionError), no network…
    }
}

info

Removing a reaction when the user has none succeeds without doing anything.

iOS

• reaction: OctopusReactionKind? — .heart, .joy, .mouthOpen, .clap, .cry or .rage; nil removes the reaction.
• postId: String — the Octopus post id.
• The function is async throws(OctopusSetReactionError).

// Set a reaction; pass reaction: nil to remove it
do {
    try await octopus.set(reaction: .heart, postId: postId)
} catch {
    // error: OctopusSetReactionError (.postNotFound, .notConnected, .noNetwork…)
}

info

Removing a reaction when the user has none throws .other.

Flutter

• reaction: OctopusReactionKind? — OctopusReactionKind.heart, joy, mouthOpen, clap, cry or rage; null removes the reaction.
• postId: String — the Octopus post id.
• Returns Future<OctopusResult<void, SetReactionError>>.

// Set a reaction; pass null to remove it
final result = await octopus.setReaction(OctopusReactionKind.heart, postId);
result
  ..onSuccess((_) {
    // Reaction updated
  })
  ..onError((error) {
    // SetReactionError: SetReactionPostNotFoundError, SetReactionReactionError…
    debugPrint(error.errorMessage);
  });

info

SetReactionError is sealed: SetReactionUnknownReactionError, SetReactionPostNotFoundError or SetReactionReactionError.

React Native

• postId: string — the Octopus post id. It comes first.
• reaction: OctopusReactionKind | null — 'heart', 'joy', 'mouthOpen', 'clap', 'cry' or 'rage'; null removes the reaction.
• Returns Promise<void>; a failure rejects with an error you can test with isSetReactionError.

import { setReaction, isSetReactionError } from '@octopus-community/react-native';

try {
  // Set a reaction; pass null to remove it
  await setReaction(postId, 'heart');
} catch (error) {
  if (isSetReactionError(error)) {
    console.warn(`${error.code}: ${error.message}`); // POST_NOT_FOUND, NO_NETWORK…
  }
}

info

The error code is one of UNKNOWN_REACTION, POST_NOT_FOUND, NO_NETWORK, NOT_CONNECTED, SERVER_ERROR or SET_REACTION_ERROR. Passing null when the user has no reaction does nothing.

Unity

• contentId: string — the Octopus post id.
• kind: OctopusReactionKind? — Heart, Joy, MouthOpen, Clap, Cry or Rage; null or None removes the reaction.
• onCompleted: Action and onError: Action<OctopusSetReactionError> — inspect Code (UnknownReaction, PostNotFound, ReactionError) and Message.

// Set a reaction; pass null to remove it
OctopusSDK.SetReaction(postId, OctopusReactionKind.Heart,
    onCompleted: () => { /* Reaction updated */ },
    onError: error => { /* See error.Code and error.Message */ });

info

On iOS, removing a reaction when the user has none can report ReactionError. The callbacks run on a later Unity update, and wait while the Octopus UI pauses Unity.

---

Sign a Bridge Share image for a picture-restricted community

Android ≥ 1.12.1iOS ≥ 1.12.3Flutter ≥ 1.12.2React Native ≥ 1.13.0Unity ≥ 1.12.2

This section applies to the create-post editor opened with prefilled content, not to the bridge posts of the steps above. When you open that editor prefilled with an image and the target community forbids member pictures, the SDK needs a signed token that authorizes the image.

Provide a signing callback. The SDK computes a content fingerprint (SHA-256 of the post's text, call to action and image) and calls your callback with it. Your backend returns a compact JWT signed HS256 with your shared secret, whose bridge_fingerprint claim equals the fingerprint. Sign on your backend: never ship the secret in the app. Without a callback, an image in such a community is rejected. Text-only posts, and communities that allow pictures, need no signature.

Android

• CreatePostScreenInfo(prefilledPost, bridgeShareTokenProvider) — bridgeShareTokenProvider: (suspend (String) -> String?)? receives the fingerprint and returns the JWT. Returning null sends the post unsigned.
• Both entry points accept it: navigateToOctopusCreatePost(info = …) in the community navigation, and OctopusCreatePostScreen(navController, info) as a standalone screen.

val info = CreatePostScreenInfo(
    prefilledPost = prefilledPost,
    bridgeShareTokenProvider = { bridgeFingerprint ->
        // Ask YOUR backend to sign the fingerprint and return the JWT
        myBackend.signBridgeShare(bridgeFingerprint)
    },
)

// In the community navigation
navController.navigateToOctopusCreatePost(info = info)

// Or as a standalone screen
OctopusCreatePostScreen(navController = navController, info = info)

iOS

• OctopusPrefilledPost(text:image:topicId:cta:sign:) — sign: (String) async throws -> String receives the fingerprint and returns the JWT. The initializer throws when the content is invalid.
• Open the editor with initialScreen: .createPost(.init(prefilledPost:)).

let prefilledPost = try OctopusPrefilledPost(
    text: "The perfect Canelés",
    image: imageData,
    topicId: foodRecipeGroupId,
    sign: { bridgeFingerprint in
        // Ask YOUR backend to sign the fingerprint and return the JWT
        try await myBackend.signBridgeShare(bridgeFingerprint)
    }
)
OctopusHomeScreen(octopus: octopus, initialScreen: .createPost(.init(prefilledPost: prefilledPost)))

info

The closure has no unsigned outcome: if it throws, the post is not published.

Flutter

• CreatePostScreenInfo(prefilledPost:, bridgeShareTokenProvider:) — bridgeShareTokenProvider: Future<String?> Function(String)? receives the fingerprint and returns the JWT.
• Pass it to showOctopusCreatePostScreen(info:).

await octopus.showOctopusCreatePostScreen(
  info: CreatePostScreenInfo(
    prefilledPost: prefilledPost,
    bridgeShareTokenProvider: (bridgeFingerprint) async {
      // Ask YOUR backend to sign the fingerprint and return the JWT
      return myBackend.signBridgeShare(bridgeFingerprint);
    },
  ),
);

info

Returning null sends the post unsigned on Android, where the server refuses it; on iOS the post is not published.

React Native

• useBridgeShareTokenProvider(provider) (a hook) or addBridgeShareTokenRequestListener(provider) (a plain function) — registered once, globally. provider receives the fingerprint and returns the JWT, or null.
• The same registration serves fetchOrCreateClientObjectRelatedPost (step 2).

import { useBridgeShareTokenProvider } from '@octopus-community/react-native';

useBridgeShareTokenProvider(async (bridgeFingerprint) => {
  // Ask YOUR backend to sign the fingerprint and return the JWT
  return myBackend.signBridgeShare(bridgeFingerprint);
});

info

The SDK only asks for a signature while a provider is registered, and treats a request left unanswered for 60 seconds as declined. Declining (returning null or throwing) sends the post unsigned on Android, where the server refuses it; on iOS the post is not published.

Unity

• OctopusPrefilledPost.SignBridgeShare: Func<string, Task<string>> — receives the fingerprint and returns the JWT. Set it only when the prefilled post carries an image and the community restricts member pictures.
• Pass the prefilled post to OctopusSDK.OpenCreatePost(prefilled). If the callback throws or returns an empty value, the post is aborted with an error.

static readonly System.Net.Http.HttpClient Http = new System.Net.Http.HttpClient();

public void ShareWithSignedImage(string groupId, string imagePath)
{
    OctopusSDK.OpenCreatePost(new OctopusPrefilledPost
    {
        Text = "The perfect Canelés",
        TopicId = groupId,
        ImagePath = imagePath,
        SignBridgeShare = async bridgeFingerprint =>
        {
            // Ask YOUR backend to sign the fingerprint and return the JWT
            return await Http.GetStringAsync(
                "https://your-backend.example/sign-bridge-share?fingerprint=" +
                System.Uri.EscapeDataString(bridgeFingerprint)).ConfigureAwait(false);
        }
    });
}

warning

SignBridgeShare runs on a background thread while the game loop is suspended. Use loop-independent I/O such as System.Net.Http, not UnityWebRequest, and do not await continuations that return to the main thread.

See Generate a JWT for a bridge "Share" with an image for the JWT contract your backend implements.

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See it in the samples

Each sample app implements the full bridge flow.

Android

The Octopus Sample app: MainViewModel prepares the client post and gets the post.

iOS

The Bridge to Client Object scenario: RecipeViewModel prepares the client post and gets the post id, and BridgeToClientObjectViewModel sets the callback.

Flutter

The Flutter example app.

React Native

A bridge scenario is not yet available in the React Native example app. Follow the steps above.

Unity

The UnityExample sample: BridgeScenario.cs prepares the client object and sets the callback.

Behavior and limits

• The content is used only when the post is created. To change a live post, edit it from the back office; do not delete and recreate it.
• The token provider is called only when a post is created, never for an existing post.
• The reaction call takes the Octopus post id, not your object id.
• Validate the content against the constraints of step 1 before you send it: an invalid field fails the request.

Next steps

• Open a specific screen — the other ways to open a post or a group.
• Groups — get the group id to label bridge posts with.
• Generate token for bridge — the backend side of the signature.
• Events reference — track the posts your users create.