mixi2r

mixi2r is an R wrapper for the mixi2 Developer Platform API.

It communicates with the API using the standard gRPC protocol (application/grpc+proto over HTTP/2 with Protocol Buffers binary encoding) and OAuth 2.0 Client Credentials authentication.

Features:

Create and retrieve posts (replies, quotes, media attachments, spoiler masks)
Send chat (DM) messages
Upload images and videos
Retrieve and assign stamps
Receive events via Webhook (Ed25519 signature verification included)

Installation

# Install from GitHub (not yet on CRAN)
# install.packages("pak")
pak::pak("statditto/mixi2r")

Prerequisites

Create an application on the mixi2 Developer Platform and obtain the following credentials.

Environment variable	Description
`MIXI2_CLIENT_ID`	OAuth2 client ID
`MIXI2_CLIENT_SECRET`	OAuth2 client secret
`MIXI2_TOKEN_URL`	Token endpoint URL
`MIXI2_API_ADDRESS`	API server address
`MIXI2_SIGNATURE_PUBLIC_KEY`	Base64-encoded Ed25519 public key (Webhook only)

Store these in your .Renviron file:

MIXI2_CLIENT_ID=your_client_id
MIXI2_CLIENT_SECRET=your_client_secret
MIXI2_TOKEN_URL=https://application-auth.mixi.social/oauth2/token
MIXI2_API_ADDRESS=application-api.mixi.social

Security: Never hard-code secrets in source code or commit them to version control. Use .Renviron or a secrets manager.

Quick start

library(mixi2r)

# Create a client (reads credentials from environment variables)
client <- mixi2_client()

# Create a post
post <- create_post(client, "Hello from R!")

# Reply to a post
create_post(client, "Thanks for your message!",
            in_reply_to_post_id = post$post_id)

# Quote a post
create_post(client, "Interesting post!",
            quoted_post_id = post$post_id)

# Post with a spoiler mask
create_post(client, "Movie spoiler content...",
            post_mask = list(
              mask_type = "POST_MASK_TYPE_SPOILER",
              caption   = "Spoiler warning"
            ))

# Get user information
users <- get_users(client, c("user_id_1", "user_id_2"))

# Get post information
posts <- get_posts(client, c("post_id_1"))

# Send a DM (requires a room_id from an incoming message event)
send_chat_message(client, room_id = "room_123", text = "Message received!")

Media upload

# Upload an image and attach it to a post
media_id <- upload_media(client, "photo.jpg")
create_post(client, "Check out this photo!", media_id_list = media_id)

# Upload a video
media_id <- upload_media(client, "video.mp4", media_type = "TYPE_VIDEO")
create_post(client, "Video post!", media_id_list = media_id)

Stamps

# Get available stamps
stamps <- get_stamps(client, language = "LANGUAGE_CODE_JP")
stamp_id <- stamps[[1]]$stamps[[1]]$stamp_id

# Assign a stamp to a post (only posts that mention your application)
add_stamp_to_post(client, post_id = "target_post_id", stamp_id = stamp_id)

Webhook server

library(mixi2r)

client <- mixi2_client()

my_handler <- function(event) {
  # Handle post creation events (mentions to your application)
  if (!is.null(event$post_created_event)) {
    ev   <- event$post_created_event
    post <- ev$post
    message("New post received: ", post$text)

    # Reply to the mention
    create_post(client, "Thanks for reaching out!",
                in_reply_to_post_id = post$post_id)
  }

  # Echo bot for DMs
  if (!is.null(event$chat_message_received_event)) {
    ev   <- event$chat_message_received_event
    msg  <- ev$message
    if (!is.null(msg$text)) {
      send_chat_message(client, room_id = msg$room_id, text = msg$text)
    }
  }
}

# Start the Webhook server (blocking)
start_webhook_server(
  handler    = my_handler,
  port       = 8080,
  public_key = Sys.getenv("MIXI2_SIGNATURE_PUBLIC_KEY")
)

Function reference

Function	RPC	Description
`mixi2_client()`	—	Create a client configuration object
`get_users(client, user_id_list)`	GetUsers	Retrieve user information
`get_posts(client, post_id_list)`	GetPosts	Retrieve post information
`create_post(client, text, ...)`	CreatePost	Create a post
`initiate_post_media_upload(client, ...)`	InitiatePostMediaUpload	Initiate a media upload
`get_post_media_status(client, media_id)`	GetPostMediaStatus	Check upload status
`upload_media(client, file_path, ...)`	(3-step wrapper)	Upload media (convenience function)
`send_chat_message(client, room_id, ...)`	SendChatMessage	Send a DM
`get_stamps(client, language)`	GetStamps	Get available stamps
`add_stamp_to_post(client, post_id, stamp_id)`	AddStampToPost	Assign a stamp to a post
`start_webhook_server(handler, port, ...)`	—	Start a Webhook event server