Using the Data Module

You can use the Data Module's CLI tool to post data on-chain and retrieve it from the ledger or an indexer service.

1

Prerequisite Setup

To interact with on-chain programs, set up Solana CLI:

• Install solana-cli by following the official documentation.

• Configure solana-cli to use your preferred RPC and network e.g.solana config set --url https://api.devnet.solana.com for devnet.

We do not recommend using public RPC nodes for production because of their low rate limits and low stake, which makes transaction landing much slower than private RPC nodes. Please reach out if you'd like help in setting up a private endpoint.

Once that's complete, set up the Data Module CLI:

curl -sSf https://nitro-da-cli.termina.technology/install.sh | sh

Run nitro-da-cli to see all the available commands and their options.

2

Select Blober Program ID

Make sure to use the correct program ID for mainnet and devnet:

Network	Program ID
Solana Mainnet	8xAuVgAygVN2sPXJzycT7AU7c9ZUJkG357HonxdFXjyc
Solana Devnet	2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH

3

Create Namespace

A namespace represents a data collection, and only your keypair is allowed to write data to it. To create a sample namespace called nitro on Solana devnet:

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    blober initialize

If you no longer need the data commitment, close the namespace and reclaim the rent from the on-chain account:

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    blober close

4

Upload Data

To upload data, store it in a file and point the CLI to that file:

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    blob upload \
    --data-path "./data.txt"

Alternatively, you can directly pipe the data into the command or pass it in as a hex string via the --data param:

cat "./data.txt" | nitro-da-cli --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" --namespace "nitro" blob upload

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    blob upload \
    --data "<some-hex-string>"

After the upload is complete, you'll see output similar to the following:

Slot: 3323, Signatures: [2Vkwid2ZTman9zvGq2Tp7P2S5CUWJ2fsZSQzGzaoFkDMAgS9xNccCvNe7PJuHrXNotsVu3BoJAsRa9jdfbZraXvS, faRmYWXPQUDJcFpqffJVE49f5aMSCLYnqp1xH3DZc3SM2Uayc7jReRfR6LjNkFxeuviSJTXMTtSAmAL9tAppwyK, 5XsiKe95nk9GmkceXQkEWapAuAcEQFFYEqMfh5kyeszSxjXepSyDbgzEXmzoQniWMdWvv6mVm5Qbyh9e1i8hHF7K, 2nk2Fj2xwM7oRfsqbmDBNqYwPCLGxHcGUujBo7napJgavMSWFEQ6C9wYmLCkKcuaetBs89vtMbtYzEKaKLKjasKd, 43zzTdgoZBR3sDphuPQTZQHZdT4Ms976bRiY8jguHPZbNPibY3k4EVnrRGKCbUy97i1RzsdMRXkYyv2KJZp9MQZE], Success: true

5

Fetch Data from Ledger

Use the signatures from the previous step to retrieve the original data from Solana:

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    blob fetch 2Vkwid2ZTman9zvGq2Tp7P2S5CUWJ2fsZSQzGzaoFkDMAgS9xNccCvNe7PJuHrXNotsVu3BoJAsRa9jdfbZraXvS faRmYWXPQUDJcFpqffJVE49f5aMSCLYnqp1xH3DZc3SM2Uayc7jReRfR6LjNkFxeuviSJTXMTtSAmAL9tAppwyK 5XsiKe95nk9GmkceXQkEWapAuAcEQFFYEqMfh5kyeszSxjXepSyDbgzEXmzoQniWMdWvv6mVm5Qbyh9e1i8hHF7K 2nk2Fj2xwM7oRfsqbmDBNqYwPCLGxHcGUujBo7napJgavMSWFEQ6C9wYmLCkKcuaetBs89vtMbtYzEKaKLKjasKd 43zzTdgoZBR3sDphuPQTZQHZdT4Ms976bRiY8jguHPZbNPibY3k4EVnrRGKCbUy97i1RzsdMRXkYyv2KJZp9MQZE

The fetch command returns hex encoded bytes, so remember to hex decode it to get the data back in its original form.

6

Fetch Data from Indexer (Optional)

If you need the data to be stored for a longer time period than the ledger's lifetime of three days, you may want to use an indexer.

Please reach out if you'd like us to set up an indexer on your behalf.

To retrieve data from the indexer, all you need to provide is the slot number at which the blob was finalized. (You can find this value from the upload command above.)

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    --indexer-url "wss://your-indexer.deployment" \
    indexer blobs 3323

This will produce an output similar to the one from fetching data from the ledger.

In addition, you can also request a proof of inclusion or proof of completeness from the indexer:

nitro-da-cli \
    --program-id "2RWsr92iL39YCLiZu7dZ5hron4oexEMbgWDg35v5U5tH" \
    --namespace "nitro" \
    --indexer-url "wss://your-indexer.deployment" \
    indexer proofs 3323

This contains metadata that prove that the indexer's return value is correct, and it hasn’t tampered with the original data posted on-chain.