Submit updates

A feed update publishes a new issuer-signed scalar value for a registered feed. Submit the value, let DALP resolve the issuer identity for the feed topic, then check the latest round before consumers depend on it.

How signed updates work

DALP signs and submits a feed update for the identity authorised for the feed topic. The feed contract validates the issuer identity, signer key purpose, nonce, timestamp, deadline, and feed value rules before storing a new round.

The submit route resolves authority differently by topic:

issuerIdentity means the OnchainID identity contract address. It is not the EOA wallet address.

Prerequisites

Before submitting feed updates:

1. Confirm the feed is registered and indexed.
2. Confirm the caller is authorised for the feed topic.
3. Know the feed's decimal precision so you can scale the value correctly.
4. Read the current nonce for the issuer identity that DALP will use for the topic.

Get the current nonce

Read the current nonce for the issuer identity on the target feed. For price-topic feeds, use the organisation OnchainID identity. For other topics, use the trusted issuer user's OnchainID identity.

curl "$DALP_API_URL/system/feeds/0xFeed/nonce/0xIdentityContract" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "issuerIdentity": "0x...",
  "currentNonce": "5",
  "nextNonce": "6"
}

Use nextNonce to understand the next strict sequential nonce the feed contract expects for that issuer identity. The nonce endpoint reads the feed contract directly and returns the current on-chain nonce plus the next expected nonce. DALP derives the nonce during submission, so the submit body does not include a nonce field.

Submit an update

Submit the scaled value and observation timestamp to the feed. When the transaction completes synchronously, the API returns the submitted value, nonce, transaction metadata, and response link:

curl -X POST "$DALP_API_URL/system/feeds/0xFeed/submit" \
  -H "X-Api-Key: $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "value": "150000000",
    "observedAt": 1700000000,
    "deadline": 0
  }'

The feed address is specified in the URL path. DALP resolves the signing identity from the feed topic and the authenticated context. For price-topic feeds, DALP uses the organisation identity when the caller has the feedsManager system role. For non-price topics, DALP uses the authenticated user's OnchainID identity when that identity is a trusted issuer for the topic.

If you are updating a token price, prefer the token price endpoint. It applies the token-level setPrice permission, resolves or creates the price feed, and submits the update with the organisation issuer identity.

Parameters

Response:

{
  "data": {
    "transactionHash": "0x...",
    "feedAddress": "0x...",
    "value": "150000000",
    "nonce": "6"
  },
  "meta": {
    "txHashes": ["0x..."]
  },
  "links": {
    "self": "/v2/system/feeds/0xFeed/submit"
  }
}

Submit flow

A successful submit stores one new round for the feed. If the contract rejects the issuer, signer, nonce, timestamp, deadline, or value, the API returns an error instead of recording a new round.

Read feed configuration

Query the immutable configuration of an issuer-signed feed to understand its parameters:

curl "$DALP_API_URL/system/feeds/0xFeed/config" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "subject": "0x...",
  "topicId": "0x...",
  "expectedSchemaHash": "0x...",
  "decimals": 8,
  "description": "USD price feed",
  "historyMode": "BOUNDED",
  "historySize": 100,
  "requirePositive": true,
  "driftAllowance": 300,
  "domainSeparator": "0x...",
  "trustedIssuersRegistry": "0x...",
  "topicSchemeRegistry": "0x..."
}

Key fields:

Check staleness

Determine whether a feed's latest value is fresh enough for a given use case:

curl "$DALP_API_URL/system/feeds/0xFeed/staleness?maxAgeSeconds=3600" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "latestUpdatedAt": "1700000000",
  "currentTimestamp": "1700003500",
  "ageSeconds": 3500,
  "maxAgeSeconds": 3600,
  "isStale": false,
  "roundId": "6",
  "answer": "150000000"
}

The staleness endpoint reads the latest round from the feed contract and compares its update timestamp with the current chain timestamp. Use staleness checks before consuming feed data in critical operations such as collateral valuation, settlement pricing, reserve checks, or reporting.

CLI equivalents

The DALP CLI exposes the same operational steps:

dalp system feeds nonce --address 0xFeed --issuer-identity 0xIdentityContract
dalp system feeds submit --address 0xFeed --value 150000000 --observed-at 1700000000
dalp system feeds staleness --address 0xFeed --max-age-seconds 3600

Related

• Data feeds overview
• Read data feeds
• Feeds update flow