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Polkadot

Polkadot transaction API

Transaction submission, fee estimation, and construction material

Documentation Provider Profile APIs.io OpenAPI GitHub

Polkadot transaction API is one of 57 APIs that Polkadot publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Transaction. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, rate-limit docs, and a GitHub repository.

This API exposes 13 operations across 13 paths, and defines 26 schemas. It is described by OpenAPI 3.2.0, at version 1.0.

Requests are made against 6 base URLs: http://localhost:8080/v1, https://polkadot-public-sidecar.parity-chains.parity.io/, https://kusama-public-sidecar.parity-chains.parity.io/, https://polkadot-asset-hub-public-sidecar.parity-chains.parity.io/, https://kusama-asset-hub-public-sidecar.parity-chains.parity.io/, http://localhost:8080.

13 operations 13 paths 26 schemas 4 GET9 POST

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
1.0
Base URL
https://polkadot.api.subscan.io
Resource Areas
1

Paths & Operations 13

Across 13 paths, the API surfaces 13 operations — 4 GET, 9 POST. Each is listed below with its method, path, parameters, and response codes.

transaction 13

Transaction submission, fee estimation, and construction material

POST
/v1/transaction
Submit transaction
submit body → 200400500503
POST
/v1/transaction/dry-run
Dry run transaction
dry_run body → 200400500503
POST
/v1/transaction/fee-estimate
Estimate transaction fee
fee_estimate body → 200400500503
GET
/v1/transaction/material
Transaction construction material
material 3 params → 200400500503
GET
/v1/transaction/material/{metadataVersion}
Transaction material with versioned metadata
material_versioned 4 params → 200400500503
POST
/v1/transaction/metadata-blob
Generate metadata blob
metadata_blob body → 200400500503
POST
/v1/transaction/parse
Parse transaction
parse body → 200400500
POST
/transaction
Submit a transaction to the node's transaction pool.
submitTransaction body → 200400
POST
/transaction/dry-run
Dry run an extrinsic.
dryrunTransaction body → 200400
POST
/transaction/fee-estimate
Receive a fee estimate for a transaction.
feeEstimateTransaction body → 200400
GET
/transaction/material
Get all the network information needed to construct a transaction offline.
getTransactionMaterial 3 params → 200400
GET
/transaction/material/{metadataVersion}
Get all the network information needed to construct a transaction offline and the version of metadata specified in metadataVersion.
getTransactionMaterialwithVersionedMetadata 3 params → 200400
POST
/transaction/metadata-blob
Get the metadata blob for offline signers.
getTransactionMetadataBlob body → 200400

Schemas 26

The contract defines 26 schemas that model the data the API accepts and returns. The most detailed are TransactionMetadataBlob (8 properties), ParseResponse (8 properties), TransactionFeeEstimateFailure (7 properties), TransactionMaterial (7 properties). Each schema is shown below with its type and property counts.

Weight
object
2 properties 2 required
SignerId
object
Signer identifier.
1 property 1 required
MethodInfo
object
Method information (pallet and method name).
2 properties 2 required
FeeEstimateResponse
object
3 properties 3 required
ParseRequest
object
Request body for transaction parsing.
1 property
ParseError
object
Error response for transaction parsing failures.
5 properties 5 required
SignatureInfo
object
Signature information for signed extrinsics.
2 properties 2 required
ParseResponse
object
Response for successful transaction parsing.
8 properties 5 required
WeightsV2
object
2 properties
MetadataBlobBody
object
Request body for generating the metadata blob. You must provide either: (1) tx (full extrinsic) with optional txAdditionalSigned, or (2) callData with included…
6 properties
TransactionDryRun
object
References: - PostDispatchInfo: https://docs.rs/frame-support/38.0.0/framesupport/dispatch/struct.PostDispatchInfo.html - DispatchError: https://docs.rs/sp-run…
2 properties
TransactionValidityError
object
The error result from an invalid transaction submitted via the dry-run endpoint.
1 property
DryRunBody
object
3 properties
TransactionFeeEstimate
object
Note: partialFee does not include any tips that you may add to increase a transaction's priority. See [computefee](https://crates.parity.io/pallettransactionpa…
3 properties
TransactionSuccess
object
1 property
TransactionDispatchOutcome
object
The result of a valid transaction submitted via the dry-run endpoint.
2 properties
TransactionFailure
TransactionFailedToSubmit
object
Error message when the node rejects the submitted transaction.
5 properties
TransactionFailedToParse
object
Error message when Sidecar fails to parse the transaction.
5 properties
TransactionMaterial
object
Note: chainName, specName, and specVersion are used to define a type registry with a set of signed extensions and types. For Polkadot and Kusama, chainName is…
7 properties
TransactionDispatchError
object
The reason why the dispatch call failed.
1 property
Error
object
4 properties
BlockIdentifiers
object
2 properties
TransactionFeeEstimateFailure
object
7 properties
Transaction
object
1 property
TransactionMetadataBlob
object
Response containing the metadata blob for offline signers. The metadataBlob contains type definitions needed to decode the specific transaction, Merkle proofs…
8 properties

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

polkadot-transaction-api-openapi.yml Raw ↑

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#Transaction
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API Details
ID
polkadot:polkadot-transaction-api
Base URL
https://polkadot.api.subscan.io
Docs
https://support.subscan.io/
Provider
Polkadot
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