# Upgrading Tendermint Core This guide provides instructions for upgrading to specific versions of Tendermint Core. ## v0.36 ### ABCI Changes #### ABCI++ Coming soon... #### ABCI Mutex In previous versions of ABCI, Tendermint was prevented from making concurrent calls to ABCI implementations by virtue of mutexes in the implementation of Tendermint's ABCI infrastructure. These mutexes have been removed from the current implementation and applications will now be responsible for managing their own concurrency control. To replicate the prior semantics, ensure that ABCI applications have a single mutex that protects all ABCI method calls from concurrent access. You can relax these requirements if your application can provide safe concurrent access via other means. This safety is an application concern so be very sure to test the application thoroughly using realistic workloads and the race detector to ensure your applications remains correct. ### RPC Changes Tendermint v0.36 adds a new RPC event subscription API. The existing event subscription API based on websockets is now deprecated. It will continue to work throughout the v0.36 release, but the `subscribe`, `unsubscribe`, and `unsubscribe_all` methods, along with websocket support, will be removed in Tendermint v0.37. Callers currently using these features should migrate as soon as is practical to the new API. To enable the new API, node operators set a new `event-log-window-size` parameter in the `[rpc]` section of the `config.toml` file. This defines a duration of time during which the node will log all events published to the event bus for use by RPC consumers. Consumers use the new `events` JSON-RPC method to poll for events matching their query in the log. Unlike the streaming API, events are not discarded if the caller is slow, loses its connection, or crashes. As long as the client recovers before its events expire from the log window, it will be able to replay and catch up after recovering. Also unlike the streaming API, the client can tell if it has truly missed events because they have expired from the log. The `events` method is a normal JSON-RPC method, and does not require any non-standard response processing (in contrast with the old `subscribe`). Clients can modify their query at any time, and no longer need to coordinate subscribe and unsubscribe calls to handle multiple queries. The Go client implementations in the Tendermint Core repository have all been updated to add a new `Events` method, including the light client proxy. A new `rpc/client/eventstream` package has also been added to make it easier for users to update existing use of the streaming API to use the polling API The `eventstream` package handles polling and delivers matching events to a callback. For more detailed information, see [ADR 075](https://tinyurl.com/adr075) which defines and describes the new API in detail. ## v0.35 ### ABCI Changes * Added `AbciVersion` to `RequestInfo`. Applications should check that the ABCI version they expect is being used in order to avoid unimplemented changes errors. * The method `SetOption` has been removed from the ABCI.Client interface. This feature was used in the early ABCI implementation's. * Messages are written to a byte stream using uin64 length delimiters instead of int64. * When mempool `v1` is enabled, transactions broadcasted via `sync` mode may return a successful response with a transaction hash indicating that the transaction was successfully inserted into the mempool. While this is true for `v0`, the `v1` mempool reactor may at a later point in time evict or even drop this transaction after a hash has been returned. Thus, the user or client must query for that transaction to check if it is still in the mempool. ### Config Changes * The configuration file field `[fastsync]` has been renamed to `[blocksync]`. * The top level configuration file field `fast-sync` has moved under the new `[blocksync]` field as `blocksync.enable`. * `blocksync.version = "v1"` and `blocksync.version = "v2"` (previously `fastsync`) are no longer supported. Please use `v0` instead. During the v0.35 release cycle, `v0` was determined to suit the existing needs and the cost of maintaining the `v1` and `v2` modules was determined to be greater than necessary. * All config parameters are now hyphen-case (also known as kebab-case) instead of snake_case. Before restarting the node make sure you have updated all the variables in your `config.toml` file. * Added `--mode` flag and `mode` config variable on `config.toml` for setting Mode of the Node: `full` | `validator` | `seed` (default: `full`) [ADR-52](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-052-tendermint-mode.md) * `BootstrapPeers` has been added as part of the new p2p stack. This will eventually replace `Seeds`. Bootstrap peers are connected with on startup if needed for peer discovery. Unlike persistent peers, there's no gaurantee that the node will remain connected with these peers. * configuration values starting with `priv-validator-` have moved to the new `priv-validator` section, without the `priv-validator-` prefix. * The fast sync process as well as the blockchain package and service has all been renamed to block sync ### Database Key Format Changes The format of all tendermint on-disk database keys changes in 0.35. Upgrading nodes must either re-sync all data or run a migration script provided in this release. The script located in `github.com/tendermint/tendermint/scripts/keymigrate/migrate.go` provides the function `Migrate(context.Context, db.DB)` which you can operationalize as makes sense for your deployment. For ease of use the `tendermint` command includes a CLI version of the migration script, which you can invoke, as in: tendermint key-migrate This reads the configuration file as normal and allows the `--db-backend` and `--db-dir` flags to change database operations as needed. The migration operation is idempotent and can be run more than once, if needed. ### CLI Changes * You must now specify the node mode (validator|full|seed) in `tendermint init [mode]` * The `--fast-sync` command line option has been renamed to `--blocksync.enable` * If you had previously used `tendermint gen_node_key` to generate a new node key, keep in mind that it no longer saves the output to a file. You can use `tendermint init validator` or pipe the output of `tendermint gen_node_key` to `$TMHOME/config/node_key.json`: ``` $ tendermint gen_node_key > $TMHOME/config/node_key.json ``` * CLI commands and flags are all now hyphen-case instead of snake_case. Make sure to adjust any scripts that calls a cli command with snake_casing ### API Changes The p2p layer was reimplemented as part of the 0.35 release cycle and all reactors were refactored to accomodate the change. As part of that work these implementations moved into the `internal` package and are no longer considered part of the public Go API of tendermint. These packages are: - `p2p` - `mempool` - `consensus` - `statesync` - `blockchain` - `evidence` Accordingly, the `node` package changed to reduce access to tendermint internals: applications that use tendermint as a library will need to change to accommodate these changes. Most notably: - The `Node` type has become internal, and all constructors return a `service.Service` implementation. - The `node.DefaultNewNode` and `node.NewNode` constructors are no longer exported and have been replaced with `node.New` and `node.NewDefault` which provide more functional interfaces. To access any of the functionality previously available via the `node.Node` type, use the `*local.Local` "RPC" client, that exposes the full RPC interface provided as direct function calls. Import the `github.com/tendermint/tendermint/rpc/client/local` package and pass the node service as in the following: ```go node := node.NewDefault() //construct the node object // start and set up the node service client := local.New(node.(local.NodeService)) // use client object to interact with the node ``` ### gRPC Support Mark gRPC in the RPC layer as deprecated and to be removed in 0.36. ### Peer Management Interface When running with the new P2P Layer, the methods `UnsafeDialSeeds` and `UnsafeDialPeers` RPC methods will always return an error. They are deprecated and will be removed in 0.36 when the legacy peer stack is removed. Additionally the format of the Peer list returned in the `NetInfo` method changes in this release to accommodate the different way that the new stack tracks data about peers. This change affects users of both stacks. ### Using the updated p2p library The P2P library was reimplemented in this release. The new implementation is enabled by default in this version of Tendermint. The legacy implementation is still included in this version of Tendermint as a backstop to work around unforeseen production issues. The new and legacy version are interoperable. If necessary, you can enable the legacy implementation in the server configuration file. To make use of the legacy P2P implemementation add or update the following field of your server's configuration file under the `[p2p]` section: ```toml [p2p] ... use-legacy = true ... ``` If you need to do this, please consider filing an issue in the Tendermint repository to let us know why. We plan to remove the legacy P2P code in the next (v0.36) release. #### New p2p queue types The new p2p implementation enables selection of the queue type to be used for passing messages between peers. The following values may be used when selecting which queue type to use: * `fifo`: (**default**) An unbuffered and lossless queue that passes messages through in the order in which they were received. * `priority`: A priority queue of messages. * `wdrr`: A queue implementing the Weighted Deficit Round Robin algorithm. A weighted deficit round robin queue is created per peer. Each queue contains a separate 'flow' for each of the channels of communication that exist between any two peers. Tendermint maintains a channel per message type between peers. Each WDRR queue maintains a shared buffered with a fixed capacity through which messages on different flows are passed. For more information on WDRR scheduling, see: https://en.wikipedia.org/wiki/Deficit_round_robin To select a queue type, add or update the following field under the `[p2p]` section of your server's configuration file. ```toml [p2p] ... queue-type = wdrr ... ``` ### Support for Custom Reactor and Mempool Implementations The changes to p2p layer removed existing support for custom reactors. Based on our understanding of how this functionality was used, the introduction of the prioritized mempool covers nearly all of the use cases for custom reactors. If you are currently running custom reactors and mempools and are having trouble seeing the migration path for your project please feel free to reach out to the Tendermint Core development team directly. ## v0.34.0 **Upgrading to Tendermint 0.34 requires a blockchain restart.** This release is not compatible with previous blockchains due to changes to the encoding format (see "Protocol Buffers," below) and the block header (see "Blockchain Protocol"). Note also that Tendermint 0.34 also requires Go 1.16 or higher. ### ABCI Changes * The `ABCIVersion` is now `0.17.0`. * New ABCI methods (`ListSnapshots`, `LoadSnapshotChunk`, `OfferSnapshot`, and `ApplySnapshotChunk`) were added to support the new State Sync feature. Previously, syncing a new node to a preexisting network could take days; but with State Sync, new nodes are able to join a network in a matter of seconds. Read [the spec](https://github.com/tendermint/tendermint/blob/master/spec/abci/apps.md) if you want to learn more about State Sync, or if you'd like your application to use it. (If you don't want to support State Sync in your application, you can just implement these new ABCI methods as no-ops, leaving them empty.) * `KV.Pair` has been replaced with `abci.EventAttribute`. The `EventAttribute.Index` field allows ABCI applications to dictate which events should be indexed. * The blockchain can now start from an arbitrary initial height, provided to the application via `RequestInitChain.InitialHeight`. * ABCI evidence type is now an enum with two recognized types of evidence: `DUPLICATE_VOTE` and `LIGHT_CLIENT_ATTACK`. Applications should be able to handle these evidence types (i.e., through slashing or other accountability measures). * The [`PublicKey` type](https://github.com/tendermint/tendermint/blob/master/proto/tendermint/crypto/keys.proto#L13-L15) (used in ABCI as part of `ValidatorUpdate`) now uses a `oneof` protobuf type. Note that since Tendermint only supports ed25519 validator keys, there's only one option in the `oneof`. For more, see "Protocol Buffers," below. * The field `Proof`, on the ABCI type `ResponseQuery`, is now named `ProofOps`. For more, see "Crypto," below. * The method `SetOption` has been removed from the ABCI.Client interface. This feature was used in the early ABCI implementation's. ### P2P Protocol The default codec is now proto3, not amino. The schema files can be found in the `/proto` directory. For more, see "Protobuf," below. ### Blockchain Protocol * `Header#LastResultsHash`, which is the root hash of a Merkle tree built from `ResponseDeliverTx(Code, Data)` as of v0.34 also includes `GasWanted` and `GasUsed` fields. * Merkle hashes of empty trees previously returned nothing, but now return the hash of an empty input, to conform with [RFC-6962](https://tools.ietf.org/html/rfc6962). This mainly affects `Header#DataHash`, `Header#LastResultsHash`, and `Header#EvidenceHash`, which are often empty. Non-empty hashes can also be affected, e.g. if their inputs depend on other (empty) Merkle hashes, giving different results. ### Transaction Indexing Tendermint now relies on the application to tell it which transactions to index. This means that in the `config.toml`, generated by Tendermint, there is no longer a way to specify which transactions to index. `tx.height` and `tx.hash` will always be indexed when using the `kv` indexer. Applications must now choose to either a) enable indexing for all transactions, or b) allow node operators to decide which transactions to index. Applications can notify Tendermint to index a specific transaction by setting `Index: bool` to `true` in the Event Attribute: ```go []types.Event{ { Type: "app", Attributes: []types.EventAttribute{ {Key: []byte("creator"), Value: []byte("Cosmoshi Netowoko"), Index: true}, }, }, } ``` ### Protocol Buffers Tendermint 0.34 replaces Amino with Protocol Buffers for encoding. This migration is extensive and results in a number of changes, however, Tendermint only uses the types generated from Protocol Buffers for disk and wire serialization. **This means that these changes should not affect you as a Tendermint user.** However, Tendermint users and contributors may note the following changes: * Directory layout changes: All proto files have been moved under one directory, `/proto`. This is in line with the recommended file layout by [Buf](https://buf.build). For more, see the [Buf documentation](https://buf.build/docs/lint-checkers#file_layout). * ABCI Changes: As noted in the "ABCI Changes" section above, the `PublicKey` type now uses a `oneof` type. For more on the Protobuf changes, please see our [blog post on this migration](https://medium.com/tendermint/tendermint-0-34-protocol-buffers-and-you-8c40558939ae). ### Consensus Parameters Tendermint 0.34 includes new and updated consensus parameters. #### Version Parameters (New) * `AppVersion`, which is the version of the ABCI application. #### Evidence Parameters * `MaxBytes`, which caps the total amount of evidence. The default is 1048576 (1 MB). ### Crypto #### Keys * Keys no longer include a type prefix. For example, ed25519 pubkeys have been renamed from `PubKeyEd25519` to `PubKey`. This reduces stutter (e.g., `ed25519.PubKey`). * Keys are now byte slices (`[]byte`) instead of byte arrays (`[]byte`). * The multisig functionality that was previously in Tendermint now has a new home within the Cosmos SDK: [`cosmos/cosmos-sdk/types/multisig`](https://github.com/cosmos/cosmos-sdk/blob/master/crypto/types/multisig/multisignature.go). #### `merkle` Package * `SimpleHashFromMap()` and `SimpleProofsFromMap()` were removed. * The prefix `Simple` has been removed. (For example, `SimpleProof` is now called `Proof`.) * All protobuf messages have been moved to the `/proto` directory. * The protobuf message `Proof` that contained multiple ProofOp's has been renamed to `ProofOps`. As noted above, this affects the ABCI type `ResponseQuery`: The field that was named Proof is now named `ProofOps`. * `HashFromByteSlices` and `ProofsFromByteSlices` now return a hash for empty inputs, to conform with [RFC-6962](https://tools.ietf.org/html/rfc6962). ### `libs` Package The `bech32` package has moved to the Cosmos SDK: [`cosmos/cosmos-sdk/types/bech32`](https://github.com/cosmos/cosmos-sdk/tree/4173ea5ebad906dd9b45325bed69b9c655504867/types/bech32). ### CLI The `tendermint lite` command has been renamed to `tendermint light` and has a slightly different API. ### Light Client We have a new, rewritten light client! You can [read more](https://medium.com/tendermint/everything-you-need-to-know-about-the-tendermint-light-client-f80d03856f98) about the justifications and details behind this change. Other user-relevant changes include: * The old `lite` package was removed; the new light client uses the `light` package. * The `Verifier` was broken up into two pieces: * Core verification logic (pure `VerifyX` functions) * `Client` object, which represents the complete light client * The new light clients stores headers & validator sets as `LightBlock`s * The RPC client can be found in the `/rpc` directory. * The HTTP(S) proxy is located in the `/proxy` directory. ### `state` Package * A new field `State.InitialHeight` has been added to record the initial chain height, which must be `1` (not `0`) if starting from height `1`. This can be configured via the genesis field `initial_height`. * The `state` package now has a `Store` interface. All functions in [state/store.go](https://github.com/tendermint/tendermint/blob/56911ee35298191c95ef1c7d3d5ec508237aaff4/state/store.go#L42-L42) are now part of the interface. The interface returns errors on all methods and can be used by calling `state.NewStore(dbm.DB)`. ### `privval` Package All requests are now accompanied by the chain ID from the network. This is a optional field and can be ignored by key management systems; however, if you are using the same key management system for multiple different blockchains, we recommend that you check the chain ID. ### RPC * `/unsafe_start_cpu_profiler`, `/unsafe_stop_cpu_profiler` and `/unsafe_write_heap_profile` were removed. For profiling, please use the pprof server, which can be enabled through `--rpc.pprof_laddr=X` flag or `pprof_laddr=X` config setting in the rpc section. * The `Content-Type` header returned on RPC calls is now (correctly) set as `application/json`. ### Version Version is now set through Go linker flags `ld_flags`. Applications that are using tendermint as a library should set this at compile time. Example: ```sh go install -mod=readonly -ldflags "-X github.com/tendermint/tendermint/version.TMCoreSemVer=$(go list -m github.com/tendermint/tendermint | sed 's/ /\@/g') -s -w " -trimpath ./cmd ``` Additionally, the exported constant `version.Version` is now `version.TMCoreSemVer`. ## v0.33.4 ### Go API * `rpc/client` HTTP and local clients have been moved into `http` and `local` subpackages, and their constructors have been renamed to `New()`. ### Protobuf Changes When upgrading to version 0.33.4 you will have to fetch the `third_party` directory along with the updated proto files. ### Block Retention ResponseCommit added a field for block retention. The application can provide information to Tendermint on how to prune blocks. If an application would like to not prune any blocks pass a `0` in this field. ```proto message ResponseCommit { // reserve 1 bytes data = 2; // the Merkle root hash ++ uint64 retain_height = 3; // the oldest block height to retain ++ } ``` ## v0.33.0 This release is not compatible with previous blockchains due to commit becoming signatures only and fields in the header have been removed. ### Blockchain Protocol `TotalTxs` and `NumTxs` were removed from the header. `Commit` now consists mostly of just signatures. ```go type Commit struct { Height int64 Round int BlockID BlockID Signatures []CommitSig } ``` ```go type BlockIDFlag byte const ( // BlockIDFlagAbsent - no vote was received from a validator. BlockIDFlagAbsent BlockIDFlag = 0x01 // BlockIDFlagCommit - voted for the Commit.BlockID. BlockIDFlagCommit = 0x02 // BlockIDFlagNil - voted for nil. BlockIDFlagNil = 0x03 ) type CommitSig struct { BlockIDFlag BlockIDFlag ValidatorAddress Address Timestamp time.Time Signature []byte } ``` See [\#63](https://github.com/tendermint/spec/pull/63) for the complete spec change. ### P2P Protocol The secret connection now includes a transcript hashing. If you want to implement a handshake (or otherwise have an existing implementation), you'll need to make the same changes that were made [here](https://github.com/tendermint/tendermint/pull/3668). ### Config Changes You will need to generate a new config if you have used a prior version of tendermint. Tags have been entirely renamed throughout the codebase to events and there keys are called [compositeKeys](https://github.com/tendermint/tendermint/blob/6d05c531f7efef6f0619155cf10ae8557dd7832f/docs/app-dev/indexing-transactions.md). Evidence Params has been changed to include duration. * `consensus_params.evidence.max_age_duration`. * Renamed `consensus_params.evidence.max_age` to `max_age_num_blocks`. ### Go API * `libs/common` has been removed in favor of specific pkgs. * `async` * `service` * `rand` * `net` * `strings` * `cmap` * removal of `errors` pkg ### RPC Changes * `/validators` is now paginated (default: 30 vals per page) * `/block_results` response format updated [see RPC docs for details](https://docs.tendermint.com/master/rpc/#/Info/block_results) * Event suffix has been removed from the ID in event responses * IDs are now integers not `json-client-XYZ` ## v0.32.0 This release is compatible with previous blockchains, however the new ABCI Events mechanism may create some complexity for nodes wishing to continue operation with v0.32 from a previous version. There are some minor breaking changes to the RPC. ### Config Changes If you have `db_backend` set to `leveldb` in your config file, please change it to `goleveldb` or `cleveldb`. ### RPC Changes The default listen address for the RPC is now `127.0.0.1`. If you want to expose it publicly, you have to explicitly configure it. Note exposing the RPC to the public internet may not be safe - endpoints which return a lot of data may enable resource exhaustion attacks on your node, causing the process to crash. Any consumers of `/block_results` need to be mindful of the change in all field names from CamelCase to Snake case, eg. `results.DeliverTx` is now `results.deliver_tx`. This is a fix, but it's breaking. ### ABCI Changes ABCI responses which previously had a `Tags` field now have an `Events` field instead. The original `Tags` field was simply a list of key-value pairs, where each key effectively represented some attribute of an event occuring in the blockchain, like `sender`, `receiver`, or `amount`. However, it was difficult to represent the occurence of multiple events (for instance, multiple transfers) in a single list. The new `Events` field contains a list of `Event`, where each `Event` is itself a list of key-value pairs, allowing for more natural expression of multiple events in eg. a single DeliverTx or EndBlock. Note each `Event` also includes a `Type`, which is meant to categorize the event. For transaction indexing, the index key is prefixed with the event type: `{eventType}.{attributeKey}`. If the same event type and attribute key appear multiple times, the values are appended in a list. To make queries, include the event type as a prefix. For instance if you previously queried for `recipient = 'XYZ'`, and after the upgrade you name your event `transfer`, the new query would be for `transfer.recipient = 'XYZ'`. Note that transactions indexed on a node before upgrading to v0.32 will still be indexed using the old scheme. For instance, if a node upgraded at height 100, transactions before 100 would be queried with `recipient = 'XYZ'` and transactions after 100 would be queried with `transfer.recipient = 'XYZ'`. While this presents additional complexity to clients, it avoids the need to reindex. Of course, you can reset the node and sync from scratch to re-index entirely using the new scheme. We illustrate further with a more complete example. Prior to the update, suppose your `ResponseDeliverTx` look like: ```go abci.ResponseDeliverTx{ Tags: []kv.Pair{ {Key: []byte("sender"), Value: []byte("foo")}, {Key: []byte("recipient"), Value: []byte("bar")}, {Key: []byte("amount"), Value: []byte("35")}, } } ``` The following queries would match this transaction: ```go query.MustParse("tm.event = 'Tx' AND sender = 'foo'") query.MustParse("tm.event = 'Tx' AND recipient = 'bar'") query.MustParse("tm.event = 'Tx' AND sender = 'foo' AND recipient = 'bar'") ``` Following the upgrade, your `ResponseDeliverTx` would look something like: the following `Events`: ```go abci.ResponseDeliverTx{ Events: []abci.Event{ { Type: "transfer", Attributes: kv.Pairs{ {Key: []byte("sender"), Value: []byte("foo")}, {Key: []byte("recipient"), Value: []byte("bar")}, {Key: []byte("amount"), Value: []byte("35")}, }, } } ``` Now the following queries would match this transaction: ```go query.MustParse("tm.event = 'Tx' AND transfer.sender = 'foo'") query.MustParse("tm.event = 'Tx' AND transfer.recipient = 'bar'") query.MustParse("tm.event = 'Tx' AND transfer.sender = 'foo' AND transfer.recipient = 'bar'") ``` For further documentation on `Events`, see the [docs](https://github.com/tendermint/tendermint/blob/60827f75623b92eff132dc0eff5b49d2025c591e/docs/spec/abci/abci.md#events). ### Go Applications The ABCI Application interface changed slightly so the CheckTx and DeliverTx methods now take Request structs. The contents of these structs are just the raw tx bytes, which were previously passed in as the argument. ## v0.31.6 There are no breaking changes in this release except Go API of p2p and mempool packages. Hovewer, if you're using cleveldb, you'll need to change the compilation tag: Use `cleveldb` tag instead of `gcc` to compile Tendermint with CLevelDB or use `make build_c` / `make install_c` (full instructions can be found at ``` ### External validator signers The Unix and TCP implementations of the remote signing validator have been consolidated into a single implementation. Thus in both cases, the external process is expected to dial Tendermint. This is different from how Unix sockets used to work, where Tendermint dialed the external process. The `PubKeyMsg` was also split into separate `Request` and `Response` types for consistency with other messages. Note that the TCP sockets don't yet use a persistent key, so while they're encrypted, they can't yet be properly authenticated. See [#3105](https://github.com/tendermint/tendermint/issues/3105). Note the Unix socket has neither encryption nor authentication, but will add a shared-secret in [#3099](https://github.com/tendermint/tendermint/issues/3099). ## v0.27.0 This release contains some breaking changes to the block and p2p protocols, but does not change any core data structures, so it should be compatible with existing blockchains from the v0.26 series that only used Ed25519 validator keys. Blockchains using Secp256k1 for validators will not be compatible. This is due to the fact that we now enforce which key types validators can use as a consensus param. The default is Ed25519, and Secp256k1 must be activated explicitly. It is recommended to upgrade all nodes at once to avoid incompatibilities at the peer layer - namely, the heartbeat consensus message has been removed (only relevant if `create_empty_blocks=false` or `create_empty_blocks_interval > 0`), and the proposer selection algorithm has changed. Since proposer information is never included in the blockchain, this change only affects the peer layer. ### Go API Changes #### libs/db The ReverseIterator API has changed the meaning of `start` and `end`. Before, iteration was from `start` to `end`, where `start > end`. Now, iteration is from `end` to `start`, where `start < end`. The iterator also excludes `end`. This change allows a simplified and more intuitive logic, aligning the semantic meaning of `start` and `end` in the `Iterator` and `ReverseIterator`. ### Applications This release enforces a new consensus parameter, the ValidatorParams.PubKeyTypes. Applications must ensure that they only return validator updates with the allowed PubKeyTypes. If a validator update includes a pubkey type that is not included in the ConsensusParams.Validator.PubKeyTypes, block execution will fail and the consensus will halt. By default, only Ed25519 pubkeys may be used for validators. Enabling Secp256k1 requires explicit modification of the ConsensusParams. Please update your application accordingly (ie. restrict validators to only be able to use Ed25519 keys, or explicitly add additional key types to the genesis file). ## v0.26.0 This release contains a lot of changes to core data types and protocols. It is not compatible to the old versions and there is no straight forward way to update old data to be compatible with the new version. To reset the state do: ```sh tendermint unsafe_reset_all ``` Here we summarize some other notable changes to be mindful of. ### Config Changes All timeouts must be changed from integers to strings with their duration, for instance `flush_throttle_timeout = 100` would be changed to `flush_throttle_timeout = "100ms"` and `timeout_propose = 3000` would be changed to `timeout_propose = "3s"`. ### RPC Changes The default behaviour of `/abci_query` has been changed to not return a proof, and the name of the parameter that controls this has been changed from `trusted` to `prove`. To get proofs with your queries, ensure you set `prove=true`. Various version fields like `amino_version`, `p2p_version`, `consensus_version`, and `rpc_version` have been removed from the `node_info.other` and are consolidated under the tendermint semantic version (ie. `node_info.version`) and the new `block` and `p2p` protocol versions under `node_info.protocol_version`. ### ABCI Changes Field numbers were bumped in the `Header` and `ResponseInfo` messages to make room for new `version` fields. It should be straight forward to recompile the protobuf file for these changes. #### Proofs The `ResponseQuery.Proof` field is now structured as a `[]ProofOp` to support generalized Merkle tree constructions where the leaves of one Merkle tree are the root of another. If you don't need this functionality, and you used to return `` here, you should instead return a single `ProofOp` with just the `Data` field set: ```go []ProofOp{ ProofOp{ Data: , } } ``` For more information, see: * [ADR-026](https://github.com/tendermint/tendermint/blob/30519e8361c19f4bf320ef4d26288ebc621ad725/docs/architecture/adr-026-general-merkle-proof.md) * [Relevant ABCI documentation](https://github.com/tendermint/tendermint/blob/30519e8361c19f4bf320ef4d26288ebc621ad725/docs/spec/abci/apps.md#query-proofs) * [Description of keys](https://github.com/tendermint/tendermint/blob/30519e8361c19f4bf320ef4d26288ebc621ad725/crypto/merkle/proof_key_path.go#L14) ### Go API Changes #### crypto/merkle The `merkle.Hasher` interface was removed. Functions which used to take `Hasher` now simply take `[]byte`. This means that any objects being Merklized should be serialized before they are passed in. #### node The `node.RunForever` function was removed. Signal handling and running forever should instead be explicitly configured by the caller. See how we do it [here](https://github.com/tendermint/tendermint/blob/30519e8361c19f4bf320ef4d26288ebc621ad725/cmd/tendermint/commands/run_node.go#L60). ### Other All hashes, except for public key addresses, are now 32-bytes. ## v0.25.0 This release has minimal impact. If you use GasWanted in ABCI and want to enforce it, set the MaxGas in the genesis file (default is no max). ## v0.24.0 New 0.24.0 release contains a lot of changes to the state and types. It's not compatible to the old versions and there is no straight forward way to update old data to be compatible with the new version. To reset the state do: ```sh tendermint unsafe_reset_all ``` Here we summarize some other notable changes to be mindful of. ### Config changes `p2p.max_num_peers` was removed in favor of `p2p.max_num_inbound_peers` and `p2p.max_num_outbound_peers`. ```toml # Maximum number of inbound peers max_num_inbound_peers = 40 # Maximum number of outbound peers to connect to, excluding persistent peers max_num_outbound_peers = 10 ``` As you can see, the default ratio of inbound/outbound peers is 4/1. The reason is we want it to be easier for new nodes to connect to the network. You can tweak these parameters to alter the network topology. ### RPC Changes The result of `/commit` used to contain `header` and `commit` fields at the top level. These are now contained under the `signed_header` field. ### ABCI Changes The header has been upgraded and contains new fields, but none of the existing fields were changed, except their order. The `Validator` type was split into two, one containing an `Address` and one containing a `PubKey`. When processing `RequestBeginBlock`, use the `Validator` type, which contains just the `Address`. When returning `ResponseEndBlock`, use the `ValidatorUpdate` type, which contains just the `PubKey`. ### Validator Set Updates Validator set updates returned in ResponseEndBlock for height `H` used to take effect immediately at height `H+1`. Now they will be delayed one block, to take effect at height `H+2`. Note this means that the change will be seen by the ABCI app in the `RequestBeginBlock.LastCommitInfo` at block `H+3`. Apps were already required to maintain a map from validator addresses to pubkeys since v0.23 (when pubkeys were removed from RequestBeginBlock), but now they may need to track multiple validator sets at once to accomodate this delay. ### Block Size The `ConsensusParams.BlockSize.MaxTxs` was removed in favour of `ConsensusParams.BlockSize.MaxBytes`, which is now enforced. This means blocks are limitted only by byte-size, not by number of transactions.