blockbook/docs/testing.md

Testing

There are two kinds of tests in Blockbook – unit tests and integration tests. Because integration tests require running back-end daemon so they can't be executed at every build. Blockbook's build system uses conditional compilation to distinguish which tests should be executed.

There are several ways to run tests:

• make test – run unit tests only (note that make deb* and make all* commands always run also test target)
• make test-integration – run integration tests only
• make test-all – run all tests above

You can use Go's flag -run to filter which tests should be executed. Use ARGS variable, e.g. make test-all ARGS="-run TestBitcoin".

Unit tests

Unit test file must start with constraint // +build unittest followed by blank line (constraints are described here).

Every coin implementation must have unit tests. At least for parser. Usual test suite define real transaction data and try pack and unpack them. Specialities of particular coin are tested too. See examples in bcashparser_test.go, bitcoinparser_test.go and ethparser_test.go.

Integration tests

Integration tests test interface between either Blockbook's components or back-end services. Integration tests are located in tests directory and every test suite has its own package. Because RPC and synchronization are crucial components of Blockbook, it is mandatory that coin implementations have these integration tests defined. They are implemented in packages blockbook/tests/rpc and blockbook/tests/sync and both of them are declarative. For each coin there are test definition that enables particular tests of test suite and testdata file that contains test fixtures.

Not every coin implementation support full set of back-end API so it is necessary define which tests of test suite are able to run. That is done in test definition file blockbook/tests/tests.json. Configuration is hierarchical and test implementations call each level as separate subtest. Go's test command allows filter tests to run by -run flag. It perfectly fits with layered test definitions. For example, you can:

• run tests for single coin – make test-integration ARGS="-run=TestIntegration/bitcoin/"
• run single test suite – make test-integration ARGS="-run=TestIntegration//sync/"
• run single test – make test-integration ARGS="-run=TestIntegration//sync/HandleFork"
• run tests for set of coins – make test-integration ARGS="-run='TestIntegration/(bcash|bgold|bitcoin|dash|dogecoin|litecoin|snowgem|vertcoin|zcash|zelcash)/'"

Test fixtures are defined in testdata directory in package of particular test suite. They are separate JSON files named by coin. File schemes are very similar with verbose results of CLI tools and are described below. Integration tests follow the same concept, use live component or service and verify their results with fixtures.

For simplicity, URLs and credentials of back-end services, where are tests going to connect, are loaded from blockbook/configs/coins, the same place from where are production configuration files generated. There are general URLs that link to localhost. If you need run tests against remote servers, there are few options how to do it:

• temporarily change config
• SSH tunneling – ssh -nNT -L 8030:localhost:8030 remote-server
• HTTP proxy

Synchronization integration tests

Synchronization is crucial part of Blockbook and these tests test whether it is doing well. They sync few blocks from blockchain and verify them against fixtures. Ranges of blocks to sync are defined in fixtures.

• ConnectBlocks – Calls db.SyncWorker.connectBlocks, a single-thread method that is called when a new block is detected. Sync blocks and checks whether blocks and transactions from fixtures are indexed.
• ConnectBlocksParallel – Calls db.SyncWorker.ConnectBlocksParallel, a multi-thread method that is used during initial synchronization. Uses the same fixtures as ConnectBlocks.
• HandleFork – Calls db.SyncWorker.HandleFork method that rolls back blockchain if a fork is detected. Test uses two sets of blocks with the same heights in fixtures. First set – with fake blocks – is synced initially, than HandleFork method is called and finally it is checked that index contain only blocks from second set – the real blocks. Make sure that fake blocks have hashes of real blocks out of a sync range. It is important because Blockbook attempts to load these blocks and if it is unsuccessful the test fails. A good practice is use blocks with a height about 20 lower than syncRanges.lower and decreasing.

Back-end RPC integration tests

This kind of tests test bchain.BlockChain implementation and its capability to communicate with back-end RPC.

Tests listed below just call back-end RPC methods with parameters from fixture file and check results against same fixture file. So data in fixture file must be related together.

• GetBlockHash – Calls BlockChain.GetBlockHash with height and checks returned hash.
• GetBlockHeader – Calls BlockChain.GetBlockHeader with hash and check returned header. Note that only fields that are significant are Hash and Height, they are checked against fixtures. Scheme of transaction data in fixtures is very similar to verbose result of getrawtransaction command of CLI tools and can be copy-pasted with few modifications.
• GetBlock – Calls BlockChain.GetBlock with hash and checks returned block (actually number of transactions and their txids).
• GetTransaction – Calls BlockChain.GetTransaction with txid and checks result against transaction object, where txid is key and transaction object is value of txDetails object in fixture file.
• GetTransactionForMempool – Calls BlockChain.GetTransactionForMempool that should be version of BlockChain.GetTransaction optimized for mempool. Implementation of test is similar.
• GetMempoolEntry – Calls BlockChain.GetMempoolEntry and checks result. Because mempool is living structure it tries to load entry for random transaction in mempool repeatedly.
• EstimateSmartFee – Calls BlockChain.EstimateSmartFee for few numbers of blocks and checks if returned fee is non-negative.
• EstimateFee – Calls BlockChain.EstimateFee; implementation is same as EstimateSmartFee.
• GetBestBlockHash – Calls BlockChain.GetBestBlockHash and verifies that returned hash matches the really last block.
• GetBestBlockHeight – Calls BlockChain.GetBestBlockHeight and verifies that returned height matches the really last block.
• MempoolSync – Synchronize BlockChain's mempool and verify if sync was successful.