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Expanding collections on delivery

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Expanding collections on delivery

Gli ultimi otto messaggi ricevuti dalla Federazione
  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian well, sure, with a monolithic implementation, the client and the outbox and the delivery agent are all the same app. but they don't have to be. the model is that the client submits to the outbox, and the outbox could also talk to a separate delivery agent internally. it's all opaque from outside the outbox. your internal "outbox" is the code that serializes activities and sends them to the delivery workers.

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  • julian@activitypub.spaceundefined
    julian@activitypub.space

    @trwnh@mastodon.social said in Expanding collections on delivery:
    > say you are an outbox and you get an activity to: some id. you deref the id and get some info. what do you do?

    Simple. My outboxes send a "not supported" HTTP tag 🀣

    But I'm being facetious.

    From a C2S standpoint I suppose that makes sense. Thanks.

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  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian now remove the requirement. what do you do instead?

    - if it has ldp:inbox, send an LDN

    ...and that's it. at no point were you ever told or required to do anything else, so your followers/audience/members/etc will never get the activity even if addressed, because the collection was never expanded.

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  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian i don't think it's "inferred", and leaving ambiguous cases up to inference in specification is typically called "unspecified behavior" ;)

    say you are an outbox and you get an activity to: some id. you deref the id and get some info. what do you do?

    - in all cases, if it has an `inbox`, you send an LDN to that id if you can.
    - in case it's an as:Collection, you iterate over its items in theory and repeat step 1 recursively. (this is also problematic because it can be both paged+unpaged)

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  • julian@activitypub.spaceundefined
    julian@activitypub.space

    @trwnh@mastodon.social so collection expansion is mainly for when I am sending an activity to collections that I control?

    Then I'm wondering why this needs to be explicitly spelled out and required because it seems to be inferred already from a UX perspective.

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  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian there's probably a bunch of open issues on the https://github.com/w3c/activitypub/issues tracker regarding the problems with outbox delivery. those problems might be addressable all together, but it might instead make more sense to conceive of a sort of "LDN proxy" which handles deliveries instead (and holds your keys as an HTTP agent sending signed messages)

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  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian

    i would be fine with removing this collection expansion behavior from outbox delivery if it was decided that outbox delivery itself is problematic and should be removed -- probably in favor of the client being responsible for sending notifications, where the client can apply whatever logic it wants.

    this is kinda what mastodon does right now as a monolith -- it is both the activitypub client (submitting to its internal outbox) and also the http agent for linked data notifications.

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  • trwnh@mastodon.socialundefined
    trwnh@mastodon.social

    @julian

    > 7.1.2

    wrt inbox forwarding, this only helps when addressing collections of *someone else*, where the contents are private. for your own collections, unless you plan to deliver all such activities to yourself with the expectation that you will forward them (why didn't the outbox do it for you?^1), it doesn't help you.

    ^1: if the outbox doesn't have your credentials, then it can't do this. in this case, you or your client is responsible for deliveries, and the outbox only publishes.

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  • eli@ehlabs.netundefined

    I've got little left with #ehLabs after implementing replies and quote posts.

    General Discussion ipfs activitypub ehlabs threads
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    eli@ehlabs.netundefined
    I've got little left with #ehLabs after implementing replies and quote posts. Meta #Threads needs to catch up in their #ActivityPub implementation. My hope with ehLabs is to provide a decent quality feed algorithm and content addressability through IPFS. Images provided for testing purposes.
  • dansup@mastodon.socialundefined

    Short video is a creative medium.

    General Discussion loops activitypub tiktok
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    dansup@mastodon.socialundefined
    Short video is a creative medium. The problem arises when platforms prioritize 'time on screen' over human well-being.That's when we get outrage and doomscrolling.Loops offers a different path: A healthy, community-owned space where you control the experience. Open source, federated, and ethical.https://joinloops.org/our-mission#Loops #ActivityPub #TikTok
  • cocoa@hackers.pubundefined

    How to Build a Simple ActivityPub Reminder Bot in Python

    Uncategorized activitypub python apkit
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    cocoa@hackers.pubundefined
    This tutorial will guide you through building a simple ActivityPub bot using Python. The bot will listen for mentions and, when it receives a message in a specific format, it will schedule and send a reminder back to the user after a specified delay. For example, if a user mentions the bot with a message like "@reminder@your.host.com 10m check the oven", the bot will reply 10 minutes later with a message like "πŸ”” Reminder for @user: check the oven". Prerequisites To follow this tutorial, you will need Python 3.10+ and the following libraries: apkit[server]: A powerful toolkit for building ActivityPub applications in Python. We use the server extra, which includes FastAPI-based components. uvicorn: An ASGI server to run our FastAPI application. cryptography: Used for generating and managing the cryptographic keys required for ActivityPub. uv: An optional but recommended fast package manager. You can install these dependencies using uv or pip. # Initialize a new project with uv uv init # Install dependencies uv add "apkit[server]" uvicorn cryptography Project Structure The project structure is minimal, consisting of a single Python file for our bot's logic. . β”œβ”€β”€ main.py └── private_key.pem main.py: Contains all the code for the bot. private_key.pem: The private key for the bot's Actor. This will be generated automatically on the first run. Code Walkthrough Our application logic can be broken down into the following steps: Imports and Configuration: Set up necessary imports and basic configuration variables. Key Generation: Prepare the cryptographic keys needed for signing activities. Actor Definition: Define the bot's identity on the Fediverse. Server Initialization: Set up the apkit ActivityPub server. Data Storage: Implement a simple in-memory store for created activities. Reminder Logic: Code the core logic for parsing reminders and sending notifications. Endpoint Definitions: Create the necessary web endpoints (/actor, /inbox, etc.). Activity Handlers: Process incoming activities from other servers. Application Startup: Run the server. Let's dive into each section of the main.py file. 1. Imports and Configuration First, we import the necessary modules and define the basic configuration for our bot. # main.py import asyncio import logging import re import uuid import os from datetime import timedelta, datetime # Imports from FastAPI, cryptography, and apkit from fastapi import Request, Response from fastapi.responses import JSONResponse from cryptography.hazmat.primitives.asymmetric import rsa from cryptography.hazmat.primitives import serialization as crypto_serialization from apkit.config import AppConfig from apkit.server import ActivityPubServer from apkit.server.types import Context, ActorKey from apkit.server.responses import ActivityResponse from apkit.models import ( Actor, Application, CryptographicKey, Follow, Create, Note, Mention, Actor as APKitActor, OrderedCollection, ) from apkit.client import WebfingerResource, WebfingerResult, WebfingerLink from apkit.client.asyncio.client import ActivityPubClient # --- Logging Setup --- logging.basicConfig(level=logging.INFO) logger = logging.getLogger(__name__) # --- Basic Configuration --- HOST = "your.host.com" # Replace with your domain USER_ID = "reminder" # The bot's username Make sure to replace your.host.com with the actual domain where your bot will be hosted. These values determine your bot's unique identifier (e.g., @reminder@your.host.com). 2. Key Generation and Persistence ActivityPub uses HTTP Signatures to secure communication between servers. This requires each actor to have a public/private key pair. The following code generates a private key and saves it to a file if one doesn't already exist. # main.py (continued) # --- Key Persistence --- KEY_FILE = "private_key.pem" # Load the private key if it exists, otherwise generate a new one if os.path.exists(KEY_FILE): logger.info(f"Loading existing private key from {KEY_FILE}.") with open(KEY_FILE, "rb") as f: private_key = crypto_serialization.load_pem_private_key(f.read(), password=None) else: logger.info(f"No key file found. Generating new private key and saving to {KEY_FILE}.") private_key = rsa.generate_private_key(public_exponent=65537, key_size=2048) with open(KEY_FILE, "wb") as f: f.write(private_key.private_bytes( encoding=crypto_serialization.Encoding.PEM, format=crypto_serialization.PrivateFormat.PKCS8, encryption_algorithm=crypto_serialization.NoEncryption() )) # Generate the public key from the private key public_key_pem = private_key.public_key().public_bytes( encoding=crypto_serialization.Encoding.PEM, format=crypto_serialization.PublicFormat.SubjectPublicKeyInfo ).decode('utf-8') 3. Actor Definition Next, we define the bot's Actor. The Actor is the bot's identity in the ActivityPub network. We use the Application type, as this entity is automated. # main.py (continued) # --- Actor Definition --- actor = Application( id=f"https://{HOST}/actor", name="Reminder Bot", preferredUsername=USER_ID, summary="A bot that sends you reminders. Mention me like: @reminder 5m Check the oven", inbox=f"https://{HOST}/inbox", # Endpoint for receiving activities outbox=f"https://{HOST}/outbox", # Endpoint for sending activities publicKey=CryptographicKey( id=f"https://{HOST}/actor#main-key", owner=f"https://{HOST}/actor", publicKeyPem=public_key_pem ) ) 4. Server Initialization We initialize the ActivityPubServer from apkit, providing it with a function to retrieve our Actor's keys for signing outgoing activities. # main.py (continued) # --- Key Retrieval Function --- async def get_keys_for_actor(identifier: str) -> list[ActorKey]: """Returns the key for a given Actor ID.""" if identifier == actor.id: return [ActorKey(key_id=actor.publicKey.id, private_key=private_key)] return [] # --- Server Initialization --- app = ActivityPubServer(apkit_config=AppConfig( actor_keys=get_keys_for_actor # Register the key retrieval function )) 5. In-Memory Storage and Cache To serve created activities, we need to store them somewhere. For simplicity, this example uses a basic in-memory dictionary as a store and a cache. In a production application, you would replace this with a persistent database (like SQLite or PostgreSQL) and a proper cache (like Redis). # main.py (continued) # --- In-memory Store and Cache --- ACTIVITY_STORE = {} # A simple dict to store created activities CACHE = {} # A cache for recently accessed activities CACHE_TTL = timedelta(minutes=5) # Cache expiration time (5 minutes) 6. Reminder Parsing and Sending Logic This is the core logic of our bot. The parse_reminder function uses a regular expression to extract the delay and message from a mention, and send_reminder schedules the notification. # main.py (continued) # --- Reminder Parsing Logic --- def parse_reminder(text: str) -> tuple[timedelta | None, str | None, str | None]: """Parses reminder text like '5m do something'.""" # ... (implementation omitted for brevity) # --- Reminder Sending Function --- async def send_reminder(ctx: Context, delay: timedelta, message: str, target_actor: APKitActor, original_note: Note): """Waits for a specified delay and then sends a reminder.""" logger.info(f"Scheduling reminder for {target_actor.id} in {delay}: '{message}'") await asyncio.sleep(delay.total_seconds()) # Asynchronously wait logger.info(f"Sending reminder to {target_actor.id}") # Create the reminder Note reminder_note = Note(...) # Wrap it in a Create activity reminder_create = Create(...) # Store the created activities ACTIVITY_STORE[reminder_note.id] = reminder_note ACTIVITY_STORE[reminder_create.id] = reminder_create # Send the activity to the target actor's inbox keys = await get_keys_for_actor(f"https://{HOST}/actor") await ctx.send(keys, target_actor, reminder_create) logger.info(f"Reminder sent to {target_actor.id}") 7. Endpoint Definitions We define the required ActivityPub endpoints. Since apkit is built on FastAPI, we can use standard FastAPI decorators. The main endpoints are: Webfinger: Allows users on other servers to discover the bot using an address like @user@host. This is a crucial first step for federation. /actor: Serves the bot's Actor object, which contains its profile information and public key. /inbox: The endpoint where the bot receives activities from other servers. apkit handles this route automatically, directing activities to the handlers we'll define in the next step. /outbox: A collection of the activities created by the bot. but this returns placeholder collection. /notes/{note_id} and /creates/{create_id}: Endpoints to serve specific objects created by the bot, allowing other servers to fetch them by their unique ID. Here is the code for defining these endpoints: # main.py (continued) # The inbox endpoint is handled by apkit automatically. app.inbox("/inbox") @app.webfinger() async def webfinger_endpoint(request: Request, acct: WebfingerResource) -> Response: """Handles Webfinger requests to make the bot discoverable.""" if not acct.url: # Handle resource queries like acct:user@host if acct.username == USER_ID and acct.host == HOST: link = WebfingerLink(rel="self", type="application/activity+json", href=actor.id) wf_result = WebfingerResult(subject=acct, links=[link]) return JSONResponse(wf_result.to_json(), media_type="application/jrd+json") else: # Handle resource queries using a URL if acct.url == f"https://{HOST}/actor": link = WebfingerLink(rel="self", type="application/activity+json", href=actor.id) wf_result = WebfingerResult(subject=acct, links=[link]) return JSONResponse(wf_result.to_json(), media_type="application/jrd+json") return JSONResponse({"message": "Not Found"}, status_code=404) @app.get("/actor") async def get_actor_endpoint(): """Serves the bot's Actor object.""" return ActivityResponse(actor) @app.get("/outbox") async def get_outbox_endpoint(): """Serves a collection of the bot's sent activities.""" items = sorted(ACTIVITY_STORE.values(), key=lambda x: x.id, reverse=True) outbox_collection = OrderedCollection( id=actor.outbox, totalItems=len(items), orderedItems=items ) return ActivityResponse(outbox_collection) @app.get("/notes/{note_id}") async def get_note_endpoint(note_id: uuid.UUID): """Serves a specific Note object, with caching.""" note_uri = f"https://{HOST}/notes/{note_id}" # Check cache first if note_uri in CACHE and (datetime.now() - CACHE[note_uri]["timestamp"]) < CACHE_TTL: return ActivityResponse(CACHE[note_uri]["activity"]) # If not in cache, get from store if note_uri in ACTIVITY_STORE: activity = ACTIVITY_STORE[note_uri] # Add to cache before returning CACHE[note_uri] = {"activity": activity, "timestamp": datetime.now()} return ActivityResponse(activity) return Response(status_code=404) # Not Found @app.get("/creates/{create_id}") async def get_create_endpoint(create_id: uuid.UUID): """Serves a specific Create activity, with caching.""" create_uri = f"https://{HOST}/creates/{create_id}" if create_uri in CACHE and (datetime.now() - CACHE[create_uri]["timestamp"]) < CACHE_TTL: return ActivityResponse(CACHE[create_uri]["activity"]) if create_uri in ACTIVITY_STORE: activity = ACTIVITY_STORE[create_uri] CACHE[create_uri] = {"activity": activity, "timestamp": datetime.now()} return ActivityResponse(activity) return Response(status_code=404) 8. Activity Handlers We use the @app.on() decorator to define handlers for specific activity types posted to our inbox. on_follow_activity: Automatically accepts Follow requests. on_create_activity: Parses incoming Create activities (specifically for Note objects) to schedule reminders. # main.py (continued) # Handler for Follow activities @app.on(Follow) async def on_follow_activity(ctx: Context): """Automatically accepts follow requests.""" # ... (implementation omitted for brevity) # Handler for Create activities @app.on(Create) async def on_create_activity(ctx: Context): """Parses mentions to schedule reminders.""" activity = ctx.activity # Ignore if it's not a Note if not (isinstance(activity, Create) and isinstance(activity.object, Note)): return Response(status_code=202) note = activity.object # Check if the bot was mentioned is_mentioned = any( isinstance(tag, Mention) and tag.href == actor.id for tag in (note.tag or []) ) if not is_mentioned: return Response(status_code=202) # ... (Parse reminder text) delay, message, time_str = parse_reminder(command_text) # If parsing is successful, schedule the reminder as a background task if delay and message and sender_actor: asyncio.create_task(send_reminder(ctx, delay, message, sender_actor, note)) reply_content = f"<p>βœ… OK! I will remind you in {time_str}.</p>" else: # If parsing fails, send usage instructions reply_content = "<p>πŸ€” Sorry, I didn\'t understand. Please use the format: `@reminder [time] [message]`.</p><p>Example: `@reminder 10m Check the oven`</p>" # ... (Create and send the reply Note) 9. Running the Application Finally, we run the application using uvicorn. # main.py (continued) if __name__ == "__main__": import uvicorn logger.info("Starting uvicorn server...") uvicorn.run(app, host="0.0.0.0", port=8000) How to Run the Bot Set the HOST and USER_ID variables in main.py to match your environment. Run the server from your terminal: uvicorn main:app --host 0.0.0.0 --port 8000 Your bot will be running at http://0.0.0.0:8000. Now you can mention your bot from anywhere in the Fediverse (e.g., @reminder@your.host.com) to set a reminder. Next Steps This tutorial covers the basics of creating a simple ActivityPub bot. Since it only uses in-memory storage, all reminders will be lost on server restart. Here are some potential improvements: Persistent Storage: Replace the in-memory ACTIVITY_STORE with a database like SQLite or PostgreSQL. Robust Task Queuing: Use a dedicated task queue like Celery with a Redis or RabbitMQ broker to ensure reminders are not lost if the server restarts. Advanced Commands: Add support for more complex commands, such as recurring reminders. We hope this guide serves as a good starting point for building your own ActivityPub applications! https://fedi-libs.github.io/apkit/ https://github.com/fedi-libs/apkit https://github.com/AmaseCocoa/activitypub-reminder-bot
  • Guest?

    Ver. 05 | install and/or move friendica to ubuntu 22.04 LTS VPS server

    General Discussion friendica fediverse activitypub debian linux feditips fedihelp howto
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    Guest?
    EDIT - informationThis tutorial is supposed to be published by the tutorial profile of this server.It is designed to have several chapters, each being distinctively seperated by an own titel. In total as of now there are like besides this introduction like 6 chapters.posting and edition time of and by this EDIT profileof ver05 as of now 1hsmastodon review contact: @bitpickup--Categories:@helpers@forum.friendi.ca SPOILER - click to open/close || IntroductionThis tutorial is an adaption of the tutorial "creating a friendica server - ubuntu" by @hankg based on the experience of the installation report by @jesuisatirebitpickup:squeet.me/display/962c3e10-576…and specific help by @raroun.Server specs and friendica version used:VPS server | Ubuntu 22.04 LTSPHP Version 8.1.2-1ubuntu2.144 Core CPU, 8 GB Ram with 300GB NVME DiskFriendica [STABLE] | 'Giant Rhubarb' 2023.05 - 1518SPOILER - click to open/close || Installation environment and HowToThe only reasonable way to work with a VPSserver on the web is using the console.If you are not familiar with that don't worry, it is easy and the only thing you have to do is being able to copy/paste the commands displayed:Β‘Copy/paste only the codeBoxes like this one, located outside of the spoilers of this tutorial one after another without altering the sequence!Of course it is necessary to change the specific file names and passwords for you indiviual site, but that's all. promise!On the console you wont be able to copy/paste with the keyboard ctrl-C/ctrl-V technique, you'll have to use the mouse "right click, chose option" technique.This tutorial was created on a #debian #linux desktop environment.There shouldn't be differences if you want to do this from a #windows machine.The method used for communication between your local computer and the VPS server is called #SSH:Wikipedia - Secure Shell:"Cryptographic network protocol for secure data communication, remote shell services or command execution and other secure network services between two networked computers."#linux #debian #ubuntu #friendica #fediVerse #fediTutorial #tutorial #fediHelp #fediTips #activityPub #HowTo #DIY #VPS #server #selfHosting@admin@tupambae.org @tutorial@tupambae.org