goodbye

README

Goodbye

Goodbye is a Go application, when someone unfollows you on Twitter, it will Direct Message you their Twitter handle.

It can be run as a daemon that checks your account for unfollowers every 5 minutes (with Docker support), or as a serverless function on Google Cloud Functions (GCF) with periodic invocation through Google Cloud Scheduler.

Installation

First, you will need a config.json file containing Twitter API credentials.

Create a Twitter application on https://dev.twitter.com and access tokens for the application. Then, create a config.json file with in the format:

{
  "consumerKey": "<value>",
  "consumerSecret": "<value>",
  "accessToken": "<value>",
  "accessSecret": "<value>"
}

You have two options:

1. Run as a Docker container (requires an always-on Linux machine)
2. Run as a serverless function (requires Google Cloud Functions)

Option 1: Installation with Docker

Clone this repo on a Linux server with docker installed and build the Docker image in the repository root directory:

docker build -t goodbye .

Then run the container (specify path to config.json in -v argument):

docker run -d --restart=always \
    -v /your/path/to/config.json:/etc/goodbye/config.json \
    --name=goodbye-agent \
    goodbye

Check if it is running fine: docker logs -f goodbye-agent.

You can use -e KEY=VALUE format to "docker run" command to customize some parameters through environment variables:

• GOODBYE_CONFIG_PATH path to the config file (defaults to /etc/goodbye/config.json)
• GOODBYE_POLLING_INTERVAL API polling interval duration in Go time.Duration format (defaults to 5m)

Option 2: Run as a serverless function on Google Cloud Functions

This is how I run it (recommended!) and it costs nearly 0$/month.

1. Clone this repo and navigate to cmd/gcf directory.

2. (Optional) If you have go installed, run go build here to see if it builds without any error messages.

3. Copy your config.json file here.

4. Create a new Google Cloud Storage bucket to store follower IDs:

   BUCKET_NAME=pick-a-name
   gsutil mb gs://$BUCKET_NAME
   

5. Upload an empty file named ids to GCS bucket

   touch ids
   gsutil cp ./ids gs://$BUCKET_NAME/ids
   

6. View your function's details on Google Cloud Console, note its Service Account field.

7. Use gcloud to give service account of the GCF app permissions on the GCS bucket:

   gsutil iam ch serviceAccount:"$(gcloud config get-value core/project)"@appspot.gserviceaccount.com:objectAdmin gs://$BUCKET_NAME
   

8. Use gcloud in this directory to create a function (change the YOUR_BUCKET_NAME occurrence below):

   gcloud alpha functions deploy goodbye \
     --memory 128MB \
     --trigger-http \
     --region us-central1 \
     --entry-point GoodbyeHandler \
     --runtime go111 \
     --set-env-vars GCS_BUCKET=$BUCKET_NAME,GCS_OBJECT=ids,GOODBYE_CONFIG_PATH=config.json
   

9. Visit the function's trigger URL and you should see an OK response.

10. Create a Google Cloud Scheduler job every 10 minutes to call the endpoint of your function.

How it works

This program runs periodically download the list of your followers and compare it with the previous version to see who is no longer there (meaning, unfollowed you). Then it sends a DM to your with their twitter @username.

If you followed Option 1 (docker container), the machine should be running all the time so the program can check the follower list every 5 minutes.

Demo

Author

Copyright (c) 2013-2019, Ahmet Alp Balkan

Made in Bellevue,WA and Seattle, WA with love.

Documentation

Overview

Package goodbye does not contain any direct exports. See pkg/ sub-packages for utility package and cmd/ for executables.