EthereumConnector

Interacts with the Ethereum blockchain network. The functions include reading transaction, address, or block information, sending transactions, or interaction with deployed contracts.

Jump to Configuration

Typical Uses

Reading transaction, address, or block information
Sending transactions
Interacting with deployed contracts

How does it work?

The Ethereum blockchain is an immutable and distributed ledger. Once data is stored on the blockchain it cannot be changed or deleted. Information is added to the network by sending a transaction. Ethereum also allows code execution called contracts, which together can create decentralized applications (Dapps). The EthereumConnector allows:

Reading stored information
Storing data
Interacting with Dapps

There are 2 methods of connecting to the Ethereum network through the connector.

An rpc url to an ethereum node. https://infura.io is a popular node service, or you can use a local or another hosted node.
An API Key from https://etherscan.io.

A private key is required to send a transaction. The key is generated when you create an ethereum wallet.

Usage Notes

There are multiple ethereum networks. The public mainnet requires real ether for the transaction fee to send transactions. For testing purposes, we recommend using a testnet as transactions are free and ether has no monetary value. However, testnets should only be for testing purposes and should not be used for production.

Configuration

Input Ports

Output Ports

Parameters

Authentication

Credential Source	The EthereumConnector has 2 methods for accessing the Ethereum network. Node - An rpc http endpoint. Etherscan - an API key from https://etherscan.io
Node URL	The URL to use when Node is chosen as the Credential Source.
Etherscan API Key	The API Key to use when Etherscan is chosen as the Credential Source.
Network	The network for Etherscan to use. “Mainnet” is the main ethereum chain. We recommend using the Ropsten testnet for development. You enter any testnet supported by etherscan, i.e. “Kovan”, but your results may vary.

Request

Action

The type of operation to perform. Choices are:

Get Address Meta
Get Address Transactions
Get Block Meta
Get Block Transactions
Get Transaction
Read Contract
Send Transaction
Write Contract

The remaining parameters available depend on the value of the Request > Action parameter. Parameters for each Action are detailed below.

Parameters - Get Address Meta Action

Retrieves metadata information for an address.

Get Address Options

Address

The ethereum address.

Output Attributes

_balance	The ether balance of the address.
_transaction_count	The number of transactions going out from an address.

Parameters - Get Address Transactions Action

Retrieves transactions from the address as features.

If using the Node credential source, only the transactions in the last 100 blocks are returned. This is about 20 minutes back in time on the mainnet. It is recommended to use Etherscan to retrieve all outgoing transactions on an address as the last 10000 transactions can be retrieved.

Get Address Options

Address	The ethereum address.
Encoding	The encoding used for the _input output attribute value.

Output Attributes

_block_hash	The block hash of the transaction.
_block_number	The block number of the transaction.
_from_address	Address the transaction was from.
_gas	The gas used to send the transaction.
_gas_price	The gas price when the transaction was sent.
_hash	The hash of the transaction.
_input	The data on the transaction.
_to_address	Address the transaction is to.
_transaction_index	The integer transaction index in the block.
_value	Ether value of the transaction.

Parameters - Get Block Meta Action

Retrieves metadata information on a block.

Get Block Options

Block Number

The block number or block hash.

Output Attributes

_difficulty	The difficulty of the block.
_extra_data	Extra data added to the block when it was created.
_gas_limit	The gas limit set on the block.
_gas_used	The gas used mining the block.
_hash	The block hash.
_latest_block_number	The most recent block number.
_miner	The address that mined the block.
_number	The block number.
_parent_hash	Hash of the block’s parent.
_size	The total size in bytes.
_timestamp	The time the block was created.
_total_difficulty	The total difficulty of mining the block.

Parameters - Get Block Transactions Action

Retrieves transactions on the block as features.

Get Block Options

Block Number	The block number or block hash.
Encoding	The encoding used for the _input output attribute value.

Output Attributes

_block_hash	The block hash of the transaction.
_block_number	The block number of the transaction.
_gas	The gas used to send the transaction.
_gas_price	The gas price when the transaction was sent.
_from_address	Address the transaction was from.
_hash	The hash of the transaction.
_input	The data on the transaction.
_to_address	Address the transaction is to.
_transaction_index	The integer transaction index in the block.
_value	Ether value of the transaction.

Parameters - Get Transaction Action

Retrieves a single transaction.

Get Transaction Options

Transaction	The hash of the transaction.
Encoding	The encoding used for the _input output attribute value.

Output Attributes

_block_hash	The block hash of the transaction.
_block_number	The block number of the transaction.
_gas	The gas used to send the transaction.
_gas_price	The gas price when the transaction was sent.
_from_address	Address the transaction was from.
_hash	The hash of the transaction.
_input	The data on the transaction.
_to_address	Address the transaction is to.
_transaction_index	The integer transaction index in the block.
_value	Ether value of the transaction.

Parameters - Read Contract Action

Read a method on a deployed contract.

Contract Options

Contract Address	The address where the contract lives.
ABI	A file that contains the application binary interface.
Contract Function	The name of the function to call.

Output Attributes

_value

The value of the called function. When using the node connection type, the output value will be formatted to the function return type. Etherscan will return the unformatted byte value.

Parameters - Send Transaction Action

Send a transaction to the network.

Send Transaction Options

Private Key	The private key used to sign the transaction.
From	The address where the transaction is sent from.
To	The address to send the transaction to.
Value (Eth)	The value of the transaction in Eth.
Data	Added data to the transaction.
Encoding	The encoding used for the data parameter.
Gas Limit	The max amount of gas to use.
Gas Price (Gwei)	The price set for gas. If the transaction fails, try increasing the gas price.
Wait for receipt	If Yes, wait until the transaction is broadcasted on the network with a hash before returning the feature. If No, immediately return the feature.

Output Attributes

_block_hash	The block hash of the transaction.
_block_number	The block number of the transaction.
_gas	The gas used to send the transaction.
_gas_price	The gas price when the transaction was sent.
_from_address	Address the transaction was from.
_hash	The hash of the transaction.
_input	The data on the transaction.
_to_address	Address the transaction is to.
_transaction_index	The integer transaction index in the block.
_value	Ether value of the transaction.

Parameters - Write Contract Action

Execute a write method on a deployed contract.

Write Contract Options

Private Key	The private key used to sign the transaction.
ABI	A file that contains the application binary interface.
From Address	The address where the transaction is sent from.
Contract Address	The address where to execute the function.
Contract Function	The function to execute.
Function Params	The parameters of the function in comma-separated form arg1,arg2.
Gas Limit	The max amount of gas to use.
Gas Price (Gwei)	The price set for gas. If the transaction fails, try increasing the gas price.
Wait for receipt	If Yes, wait until the transaction is broadcasted on the network with a hash before returning the feature. If No, immediately return the feature.

Output Attributes

_block_hash	The block hash of the transaction.
_block_number	The block number of the transaction.
_gas	The gas used to send the transaction.
_gas_price	The gas price when the transaction was sent.
_from_address	Address the transaction was from.
_hash	The hash of the transaction.
_input	The data on the transaction.
_to_address	Address the transaction is to.
_transaction_index	The integer transaction index in the block.
_value	Ether value of the transaction.

Editing Transformer Parameters

Transformer parameters can be set by directly entering values, using expressions, or referencing other elements in the workspace such as attribute values or user parameters. Various editors and context menus are available to assist. To see what is available, click beside the applicable parameter.

How to Set Parameter Values

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters.

Using the Text Editor

The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.

Text Editor

Using the Arithmetic Editor

The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.

Arithmetic Editor

Conditional Values

Set values depending on one or more test conditions that either pass or fail.

Parameter Condition Definition Dialog

Content

Expressions and strings can include a number of functions, characters, parameters, and more.

When setting values - whether entered directly in a parameter or constructed using one of the editors - strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.

Content Types

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	FME and workspace-specific parameters may be used.
Creating and Modifying User Parameters	Create your own editable parameters.

Dialog Options - Tables

Table Tools

Transformers with table-style parameters have additional tools for populating and manipulating values.

Row Reordering

Enabled once you have clicked on a row item. Choices include:

Add a row
Remove a row
Move current row up one
Move current row down one
Move current row to top
Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

Cut a row - delete and copy to clipboard
Copy a row to the clipboard
Paste a row from the clipboard

Cut, copy, and paste may be used within a transformer, or between transformers.

Filter

Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer - it does not alter which attributes are output.

Import

Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers.

Reset/Refresh

Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers.

Note: Not all tools are available in all transformers.

For more information, see Transformer Parameter Menu Options.

Reference

Processing Behavior	Feature-Based
Feature Holding	No
Dependencies	Ethereum connection
Aliases
History	Released FME 2019.1

FME Community

The FME Community is the place for demos, how-tos, articles, FAQs, and more. Get answers to your questions, learn from other users, and suggest, vote, and comment on new features.

Search for all results about the EthereumConnector on the FME Community.

Examples may contain information licensed under the Open Government Licence – Vancouver, Open Government Licence - British Columbia, and/or Open Government Licence – Canada.