Skip to main content
Research Preview — This API is under development.

​
Length

Calculate the length of a line in meters. 
POST /compute/v0/length

​
Request body

​
chainId
number
required
Target chain ID (e.g., 84532 for Base Sepolia).
​
geometry
Input
required
The line geometry to measure. See Input types for accepted formats.
​
schema
string
EAS schema UID. The server uses a default schema if not provided.
​
recipient
string
Ethereum address to receive the attestation. Defaults to the zero address.

​
Example request

curl -X POST https://api.astral.global/compute/v0/length \
  -H "Content-Type: application/json" \
  -H "X-API-Key: your-api-key" \
  -d '{
    "chainId": 84532,
    "geometry": "0xline...",
    "recipient": "0xdef456..."
  }'

​
Response

Returns a NumericComputeResponse.
​
result
number
required
Length in meters (e.g., 2345.67).
​
units
string
required
Always "meters".
​
operation
string
required
Always "length".
​
timestamp
number
required
Unix timestamp of computation.
​
inputRefs
string[]
required
Array of input references.
​
attestation
AttestationData
required
Signed EAS attestation. See AttestationData.
​
delegatedAttestation
DelegatedAttestationData
required
Signature for delegated onchain submission. See DelegatedAttestationData.

​
Example response

{
  "result": 2345.67,
  "units": "meters",
  "operation": "length",
  "timestamp": 1706400000,
  "inputRefs": [
    "0xline..."
  ],
  "attestation": {
    "schema": "0x...",
    "attester": "0x590fdb53ed3f0B52694876d42367192a5336700F",
    "recipient": "0xdef456...",
    "data": "0x...",
    "revocable": true,
    "refUID": "0x0000000000000000000000000000000000000000000000000000000000000000",
    "signature": "0x..."
  },
  "delegatedAttestation": {
    "signature": "0x...",
    "attester": "0x590fdb53ed3f0B52694876d42367192a5336700F",
    "deadline": 1706403600,
    "nonce": 0
  }
}

​
Notes

  • Uses PostGIS ST_Length with geodetic calculation
  • Result is in meters with centimeter precision
  • The onchain attested value is scaled to centimeters (integer) for EVM compatibility
  • Valid for LineString and MultiLineString geometries

SDK Method

See astral.compute.length()