Helipad

This package will poll a Lightning LND node for invoices related to Podcasting 2.0 and display them in a web interface. It's intended for use as a way to see incoming Boost-a-grams and other data from podcast listeners in a browser.

Helipad is intended to run as a dockerized Umbrel app, but can also be run as a standalone executable if compiled from source.

Helipad runs as a single process web server with the LND poller running in a separate thread. Invoices are checked for every 9 seconds, parsed and stored locally in a Sqlite database. The main webserver thread then serves them to clients over HTTP(S).

After compiling, you start the binary like this:

./helipad 8080

You may pass the port number you want it to listen on, on the command line as the only argument. If you don't pass a port number it will listen by default on port 2112. (RIP Neil)

The FQDN of your LND node must be present in an environment variable called $LND_URL in order to connect to it, like this:

export LND_URL="mynode.example.com:10009"

If you don't export that variable, it will attempt to connect to "localhost:10009".

Helipad also needs your admin.macaroon and tls.cert files. It will first look for them in the locations pointed to by these two environment variables:

• LND_ADMINMACAROON
• LND_TLSCERT

Information about the Umbrel app environment is in the umbrel folder for those interested.

Configuration

Each configurable item has multiple options. They are listed in the config file here. In each case, the environment variable is tried first, then the configuration file parameter, then a sane default based on known locations in use from other projects.

The only exception to this is the listen_port which can be specified on the command line as the only argument. This is just for convenience as it's a very common thing to change during testing.

API

The very simplistic API consists of the following endpoints:

/api/v1/balance

This call returns the current channel balance that LND is reporting.

/api/v1/node_info

This call returns the node name, pubkey, and version that LND is reporting.

/api/v1/settings

This call returns the current settings that the user has set.

/api/v1/index

This call returns the most recent invoice index number that Helipad has reconciled with LND.

/api/v1/boosts

This call returns count boosts starting at index. If the old parameter is present, the boosts returned start from index and descend by count, showing older boosts. Otherwise, they start at index and ascend by count, showing newer boosts.

/api/v1/streams

This call returns count streams starting at index. If the old parameter is present, the streams returned start from index and descend by count, showing older streams. Otherwise, they start at index and ascend by count, showing newer streams.

/api/v1/sent_index

This call returns the most recent payment index number that Helipad has reconciled with LND.

/api/v1/sent

This call returns count sent boosts starting at index. If the old parameter is present, the sent boosts returned start from index and descend by count, showing older sent boosts. Otherwise, they start at index and ascend by count, showing newer sent boosts.

Webhooks

Webhooks send an HTTP POST to a user defined URL whenever a new boost, stream, or sent boost is processed by Helipad. The body of the POST will contain the following JSON format:

{
  "index": 1234,
  "time": 1714548166,
  "value_msat": 100000,
  "value_msat_total": 1000000,
  "action": 2,
  "sender": "Mark Pugner",
  "app": "CurioCaster",
  "message": "My boost message",
  "podcast": "Podcast name",
  "episode": "Episode name",
  "tlv": "{\n  \"podcast\": \"Podcast name\",\n  \"feedId\": 1234567,\n  \"episode\": \"Episode name\",\n  \"action\": \"boost\",\n  \"app_name\": \"CurioCaster\",\n  \"url\": \"https://podcast/example.xml\",\n  \"value_msat_total\": 1000000,\n  \"message\": \"My boost message\",\n  \"sender_name\": \"Mark Pugner\",\n  \"reply_address\": \"03ae9f91a0cb8ff43840e3c322c4c61f019d8c1c3cea15a25cfc425ac605e61a4a\",\n  \"remote_feed_guid\": \"b8b6971e-403e-568f-a4e6-7aa2b45e50d4\",\n  \"remote_item_guid\": \"72a3b402-8491-4cd9-823e-a621fd81b86f\",\n  \"value_msat\": 100000,\n  \"name\": \"Podcastindex.org\"\n}\n",
  "remote_podcast": "Some artist",
  "remote_episode": "Some song",
  "reply_sent": false,
  "payment_info": null
}

The fields are as follows:

• index: LND index of the invoice or payment
• time: Unix Timestamp of the item
• value_msat: Actual amount received/sent by our node
• value_msat_total: Total amount of the item
• action: Item type (1 = stream, 2 = boost, 3 = unknown, 4 = automated boost, 0 = error)
• sender: Sender's name
• app: Application used to send the item
• message: Message sent by the sender
• podcast: Name of the podcast
• episode: Name of the episode
• tlv: Raw copy of the TLV
• remote_podcast: Name of the remote podcast (during a Value Time Split)
• remote_episode: Name of the remote episode (during a Value Time Split)
• reply_sent: Flag that indicates if this item has been sent a reply boost
• payment_info: Additional payment info for sent boosts:

    "payment_info": {
      "payment_hash": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
      "pubkey": "03ae9f91a0cb8ff43840e3c322c4c61f019d8c1c3cea15a25cfc425ac605e61a4a",
      "custom_key": 696969,
      "custom_value": "XXXXXXXXXXXXXXXXXXXX",
      "fee_msat": 333,
      "reply_to_idx": null
    }

  • payment_hash: Payment hash from LND
  • pubkey: Recipient's node pubkey
  • custom_key: Recipient's wallet key
  • custom_value: Recipient's wallet ID
  • fee_msat: Fee paid to send boost
  • reply_to_idx: Index of item that was replied to

CSV export

There is an endpoint called /csv that will export boosts as a CSV list to make organizing easier. The parameters behave just like the boosts and streams endpoints, but also accept an end parameter which limits how far back in time the CSV export list goes. An example call would look like this:

GET http://localhost:2112/csv?index=38097&count=13049&old=true&end=25048

This will give back a csv list of 13,049 boosts starting at index 38097 and descending back in time - but will not go past index number 25048.

Development

Quick Start (Debian/Linux Mint/Ubuntu/Pop!_OS)

In order to run Helipad locally you need to install the Rust Compiler rustc, the Rust package manager cargo, and the needed shared libraries libssl-dev/libsqlite3-dev. Clone the Github repo with git clone ... and enter the helipad directory. Note, all commands going forward will need to be ran from this directory. cargo run will compile and run helipad. If Helipad fails to start you may need to edit helipad.conf or set/unset Environment Variables.

sudo apt install rustc cargo libssl-dev libsqlite3-dev
git clone https://github.com/Podcastindex-org/helipad.git
cd helipad
# Edit helipad.conf as needed
cargo run
# Open http://127.0.0.1:2112 in your browser

There is an example build script for quick compile/run when iterating on new features. The script sets a proper environment, does a debug compile and runs the executable.