Repository navigation
Block: add getGenesis(), SPVBlockStore: use Network in constructors - #4261
Open
msgilligan wants to merge 3 commits into
Open
msgilligan wants to merge 3 commits into
msgilligan wants to merge 3 commits into
Conversation
schildbach
reviewed
Jul 31, 2026
Comment on lines
+273
to
+281
| /** | ||
| * Get the standard full Genesis Block for a network | ||
| * @param network the network | ||
| * @return a complete block (should be treated as immutable) | ||
| */ | ||
| public static Block getGenesis(Network network) { | ||
| return NetworkParameters.of(network).getGenesisBlock(); | ||
| } | ||
|
|
Member
There was a problem hiding this comment.
Hm, I think the special genesis block is more an artifact of a network or a block chain, but not really of a block.
So I'd argue perhaps we should have a helper in Network instead. (I'm surprised we don't have than already.)
However, even if we go ahead with this PR, I think the refactoring to introduce this method should be on a separate commit.
Member
Author
There was a problem hiding this comment.
So I'd argue perhaps we should have a helper in Network instead.
I think genesis block should be constructed by Block for three reasons:
- They are instances of
Blockand the standard static factory method pattern seems to apply here. - We already have several
createGenesis()static factories inBlock(immediately below this new method) - We can't put it in
NetworkbecauseBlockand other dependencies are ino.b.corenoto.b.base(notably the currentNetworkParametersconstants, thought those could be moved)
the refactoring to introduce this method should be on a separate commit.
Agree.
Member
Author
|
@schildbach Oops, re-requested review and I have not created a separate commit. I will do that soon. In the meantime, do my arguments for why |
Member
Author
|
As requested, I factored the creation of Once that is merged this can be rebased. |
This provides a factory for genesis blocks that does not require a caller to have a NetworkParameters instance. Block is the logical home for this method, because: 1. Genesis blocks are instances of `Block` and factories that provide well-known constant instances of a type make sense to place there. 2. We already have several `createGenesis()` static factories in `Block` (immediately below this new method) 3. We can't put it in `Network` because `Block` and other dependencies are in `o.b.core` not `o.b.base`.
In some classes (CheckpointManager, SPVBlockStore, and MemoryFullPrunedBlockStore) the use of Block.getGenesis() removes the last internal dependency on NetworkParameters and allows the constructor taking NetworkParameters to be replaced with one that takes Network. In FetchBlocks, PrivateKeys, and BlockFileLoaderBitcoindTest NetworkParameters is completely removed. In other classes use of Block.getGenesis() takes us closer to removing NetworkParameters, but there are other uses that must be updated first.
Existing SPVBlockStore constructors that take NetworkParameters are deprecated. Note that the RestoreFromSeed example is now able to completely remove imports of NetworkParameters and subclasses. BlockImporter can drop NetworkParameters once the MemoryFullPrunedBlockStore constructors are updated to take Network. This is a step towards our goal of (typical) applications using only (Bitcoin)Network in API calls. This also opens the possibility of migrating genesis block parameters out of network parameters.
msgilligan
force-pushed
the
msgilligan/Block-getGenesis
branch
from
August 28, 2026 14:55
23e2fde to
19074c2
Compare
This was referenced Aug 29, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Existing SPVBlockStore constructors that take NetworkParameters are deprecated.
Note that the RestoreFromSeed example is now able to completely remove imports of NetworkParameters and subclasses.
BlockImporter can drop NetworkParameters once the MemoryFullPrunedBlockStore constructors are updated to take Network.
This is a step towards our goal of (typical) applications using only (Bitcoin)Network in API calls.
This also opens the possibility of migrating genesis block parameters out of network parameters.