Entaxy Docs

Web3j Ethereum Blockchain

Since Camel 2.22

Both producer and consumer are supported

The Ethereum blockchain component uses the web3j client API and allows you to interact with Ethereum compatible nodes such as Geth, Parity, Quorum, Infura, etc.

Maven users will need to add the following dependency to their pom.xml for this component:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-web3j</artifactId>
    <version>x.x.x</version>
    <!-- use the same version as your Camel core version -->
</dependency>

URI Format

web3j://<local/remote host:port or local IPC path>[?options]

Web3j Options

The Web3j Ethereum Blockchain component supports 38 options, which are listed below.

Name Description Default Type

addresses (common)

Contract address or a list of addresses.

List

configuration (common)

Default configuration

Web3jConfiguration

fromAddress (common)

The address the transaction is send from

String

fromBlock (common)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

fullTransactionObjects (common)

If true it returns the full transaction objects, if false only the hashes of the transactions.

false

boolean

gasLimit (common)

The maximum gas allowed in this block.

BigInteger

privateFor (common)

A transaction privateFor nodes with public keys in a Quorum network

List

quorumAPI (common)

If true, this will support Quorum API.

false

boolean

toAddress (common)

The address the transaction is directed to.

String

toBlock (common)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

topics (common)

Topics are order-dependent. Each topic can also be a list of topics. Specify multiple topics separated by comma.

String

web3j (common)

The preconfigured Web3j object.

Web3j

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

address (producer)

Contract address.

String

atBlock (producer)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

blockHash (producer)

Hash of the block where this transaction was in.

String

clientId (producer)

A random hexadecimal(32 bytes) ID identifying the client.

String

data (producer)

The compiled code of a contract OR the hash of the invoked method signature and encoded parameters.

String

databaseName (producer)

The local database name.

String

filterId (producer)

The filter id to use.

BigInteger

gasPrice (producer)

Gas price used for each paid gas.

BigInteger

hashrate (producer)

A hexadecimal string representation (32 bytes) of the hash rate.

String

headerPowHash (producer)

The header’s pow-hash (256 bits) used for submitting a proof-of-work solution.

String

index (producer)

The transactions/uncle index position in the block.

BigInteger

keyName (producer)

The key name in the database.

String

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

mixDigest (producer)

The mix digest (256 bits) used for submitting a proof-of-work solution.

String

nonce (producer)

The nonce found (64 bits) used for submitting a proof-of-work solution.

String

operation (producer)

Operation to use.

transaction

String

position (producer)

The transaction index position withing a block.

BigInteger

priority (producer)

The priority of a whisper message.

BigInteger

sha3HashOfDataToSign (producer)

Message to sign by calculating an Ethereum specific signature.

String

signedTransactionData (producer)

The signed transaction data for a new message call transaction or a contract creation for signed transactions.

String

sourceCode (producer)

The source code to compile.

String

transactionHash (producer)

The information about a transaction requested by transaction hash.

String

ttl (producer)

The time to live in seconds of a whisper message.

BigInteger

value (producer)

The value sent within a transaction.

BigInteger

basicPropertyBinding (advanced)

Whether the component should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities

false

boolean

The Web3j Ethereum Blockchain endpoint is configured using URI syntax:

web3j:nodeAddress

with the following path and query parameters:

Path Parameters (1 parameters):

Name Description Default Type

nodeAddress

Required Sets the node address used to communicate

String

Query Parameters (40 parameters):

Name Description Default Type

addresses (common)

Contract address or a list of addresses.

List

fromAddress (common)

The address the transaction is send from

String

fromBlock (common)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

fullTransactionObjects (common)

If true it returns the full transaction objects, if false only the hashes of the transactions.

false

boolean

gasLimit (common)

The maximum gas allowed in this block.

BigInteger

privateFor (common)

A transaction privateFor nodes with public keys in a Quorum network

List

quorumAPI (common)

If true, this will support Quorum API.

false

boolean

toAddress (common)

The address the transaction is directed to.

String

toBlock (common)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

topics (common)

Topics are order-dependent. Each topic can also be a list of topics. Specify multiple topics separated by comma.

String

web3j (common)

The preconfigured Web3j object.

Web3j

bridgeErrorHandler (consumer)

Allows for bridging the consumer to the Camel routing Error Handler, which mean any exceptions occurred while the consumer is trying to pickup incoming messages, or the likes, will now be processed as a message and handled by the routing Error Handler. By default the consumer will use the org.apache.camel.spi.ExceptionHandler to deal with exceptions, that will be logged at WARN or ERROR level and ignored.

false

boolean

exceptionHandler (consumer)

To let the consumer use a custom ExceptionHandler. Notice if the option bridgeErrorHandler is enabled then this option is not in use. By default the consumer will deal with exceptions, that will be logged at WARN or ERROR level and ignored.

ExceptionHandler

exchangePattern (consumer)

Sets the exchange pattern when the consumer creates an exchange. The value can be one of: InOnly, InOut, InOptionalOut

ExchangePattern

address (producer)

Contract address.

String

atBlock (producer)

The block number, or the string latest for the last mined block or pending, earliest for not yet mined transactions.

latest

String

blockHash (producer)

Hash of the block where this transaction was in.

String

clientId (producer)

A random hexadecimal(32 bytes) ID identifying the client.

String

data (producer)

The compiled code of a contract OR the hash of the invoked method signature and encoded parameters.

String

databaseName (producer)

The local database name.

String

filterId (producer)

The filter id to use.

BigInteger

gasPrice (producer)

Gas price used for each paid gas.

BigInteger

hashrate (producer)

A hexadecimal string representation (32 bytes) of the hash rate.

String

headerPowHash (producer)

The header’s pow-hash (256 bits) used for submitting a proof-of-work solution.

String

index (producer)

The transactions/uncle index position in the block.

BigInteger

keyName (producer)

The key name in the database.

String

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

mixDigest (producer)

The mix digest (256 bits) used for submitting a proof-of-work solution.

String

nonce (producer)

The nonce found (64 bits) used for submitting a proof-of-work solution.

String

operation (producer)

Operation to use.

transaction

String

position (producer)

The transaction index position withing a block.

BigInteger

priority (producer)

The priority of a whisper message.

BigInteger

sha3HashOfDataToSign (producer)

Message to sign by calculating an Ethereum specific signature.

String

signedTransactionData (producer)

The signed transaction data for a new message call transaction or a contract creation for signed transactions.

String

sourceCode (producer)

The source code to compile.

String

transactionHash (producer)

The information about a transaction requested by transaction hash.

String

ttl (producer)

The time to live in seconds of a whisper message.

BigInteger

value (producer)

The value sent within a transaction.

BigInteger

basicPropertyBinding (advanced)

Whether the endpoint should use basic property binding (Camel 2.x) or the newer property binding with additional capabilities

false

boolean

synchronous (advanced)

Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported).

false

boolean

You can append query options to the URI in the following format, ?options=value&option2=value&…​

Message Headers

Header Description

All URI options

All URI options can also be set as exchange headers.

Samples

Listen for new mined blocks and send the block hash to a jms queue:

from("web3j://http://127.0.0.1:7545?operation=ETH_BLOCK_HASH_OBSERVABLE")
    .to("jms:queue:blocks");

Use the block hash code to retrieve the block and full transaction details:

from("jms:queue:blocks")
    .setHeader(BLOCK_HASH, body())
    .to("web3j://http://127.0.0.1:7545?operation=ETH_GET_BLOCK_BY_HASH&fullTransactionObjects=true");

Read the balance of an address at a specific block number:

from("direct:start")
    .to("web3j://http://127.0.0.1:7545?operation=ETH_GET_BALANCE&address=0xc8CDceCE5d006dAB638029EBCf6Dd666efF5A952&atBlock=10");