Used for testing all maner of Ethereum JSON-RPC interactions.
Python Makefile
Latest commit fe3cc82 May 18, 2018

Ethereum Test RPC server

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Ethereum Test RPC

Limited RPC client intended for use with automated testing. Uses pythereum to run an Ethereum client behind the scenes without the need for mining or networking. The result is an Ethereum client that provides instant results and quick feedback during development.


Installing is easy, through pip:

$ pip install eth-testrpc

Or, to upgrade:

pip install eth-testrpc --upgrade

Or, to install with gevent threads

pip install eth-testrpc[gevent]

And then set the environment variable TESTRPC_THREADING_BACKEND=gevent


Installing through pip will make the testrpc-py command available on your machine:

$ testrpc

This will run testrpc on localhost:8545. You can pass through a different port (-p, --port) or domain (-d, --domain).

Implemented methods

The RPC methods currently implemented are:

  • eth_coinbase
  • eth_accounts
  • eth_gasPrice
  • eth_blockNumber
  • eth_sendTransaction
  • eth_sendRawTransaction
  • eth_call
  • eth_getCompilers
  • eth_compileSolidity
  • eth_getCode (only supports block number “latest”)
  • eth_getBalance
  • eth_getTransactionCount
  • eth_getTransactionByHash
  • eth_getTransactionReceipt
  • eth_newBlockFilter (temporarily removed until implemented in underlying library)
  • eth_newFilter (temporarily removed until implemented in underlying library)
  • eth_getFilterChanges (temporarily removed until implemented in underlying library)
  • eth_uninstallFilter (temporarily removed until implemented in underlying library)
  • eth_protocolVersion ( see rpc_configure)
  • eth_syncing ( see rpc_configure)
  • eth_mining ( see rpc_configure)
  • web3_sha3
  • web3_clientVersion
  • net_version (see rpc_configure)
  • net_listening (see rpc_configure)
  • net_peerCount (see rpc_configure)

There’s also special non-standard methods that aren’t included within the original RPC specification:

  • evm_reset : No params, no return value.
  • evm_snapshot : No params. Returns the integer id of the snapshot created.
  • evm_revert : One optional param. Reverts to the snapshot id passed, or the latest snapshot.

When calling evm_reset, the testrpc will revert the state of its internal chain back to the genesis block and it will act as if no processing of transactions has taken place. Similarly, you can use evm_snapshot and evm_revert methods to save and restore the evm state as desired. Example use cases for these methods are as follows:

  • evm_reset : Run once at the beginning of your test suite.
  • evm_snapshot : Run at the beginning of each test, snapshotting the state of the evm.
  • evm_revert : Run at the end of each test, reverting back to a known clean state.

TestRPC also exposes the evm_mine method for advancing the test evm by some number of blocks.

  • evm_mine : Optionally supply an integer for the number of blocks to mine. Default is 1 block. No return value.

TestRPC exposes the testing_timeTravel method for fast-forwarding to a future timestamp.

  • testing_timeTravel : Takes an integer timestamp that must be greater than the timestamp of the current latest block.

TestRPC exposes the rpc_configure method which can be used to modify the static values returned by the following endpoints.

  • eth_protocolVersion (default 63)
  • eth_syncing (default False)
  • eth_mining (default True)
  • net_version (default 1)
  • net_listening (default False)
  • net_peerCount (default 0)
  • homestead_block_number (default 0)
  • dao_fork_block_number (default 0)
  • anti_dos_fork_block_number (default 0)
  • clearing_fork_block_number (default 0)

The rpc_configure takes two parameters.

  • key: string representing the rpc method on which you want to change the return value.
  • value: the value that should be returned by the endpoint.

The homestead, dao, anti_dos and clearing fork configurations determine which block number the respective fork rules should come into effect. All default to 0.

TestRPC uses a default gas limit of 4000000. To change this set the environment variable TESTRPC_GAS_LIMIT to the desired value.

Releasing a new version (for eth-testrpc developers)

  • Bump version number in
  • Add entry to CHANGES.txt
  • Tag the release.
git tag -s -m "X.X.X Release" vX.X.X
git push --tags
  • Go make the release on github for the tag you just pushed
  • Build and push release to PyPI
make release




This library was originally authored by Consensys and transferred later when it was no longer maintained. A big thanks for them to creating this extremely useful library.