MultiChain extends the Bitcoin Core API with new calls and functionality

Accessing the API

To access MultiChain’s API, use the included multichain-cli command-line tool or any other JSON-RPC client. (MultiChain is compatible with any API library developed for Bitcoin Core.) The API credentials for each blockchain are stored in the ~/.multichain/[chain-name]/multichain.conf file and read by multichain-cli. These credentials are randomly generated the first time that multichaind is called for that chain. (Note that you can change this ~/.multichain/ path using the -datadir= option, and %APPDATA%\MultiChain\ is the equivalent on Windows.)

You can use multichain-cli to send a single API command in the following form:

multichain-cli [chain-name] [command] [parameters...]

Alternatively, you can use multichain-cli in interactive mode, to send multiple commands in a single session:

multichain-cli [chain-name]

Each command is then entered in the [command] [parameters...] form. To end the session, type bye, exit, quit or Control-D.

Compatibility with Bitcoin Core

MultiChain supports all commands in the Bitcoin Core API (as of version 0.10), except those which relate to Bitcoin Core’s “accounts” mechanism – see note below. In some cases, MultiChain extends Bitcoin Core’s commands in a backwards-compatible way to enable additional functionality.

A summary of Bitcoin Core commands is listed in the bitcoin wiki or consult the developer documentation for more comprehensive details. The most useful ones are listed below, along with MultiChain’s new commands.

List of API commands by category – view alphabetically

In the table below, all optional parameters are denoted in (round brackets) with non-empty default values indicated after the = symbol. You should also consult the list of error codes and messages.

General utilities
Command Parameters Description
getblockchainparams Returns a list of values of this blockchain’s parameters, which are fixed by the chain’s genesis block and the same for all nodes.
getruntimeparams Returns a selection of this node’s runtime parameters, which are set when the node starts up. Some parameters can be modified while MultiChain is running using setruntimeparam.
setruntimeparam param value Sets the runtime parameter param to value and immediately applies the change. Currently supported parameters: autosubscribe bantx handshakelocal hideknownopdrops lockadminminerounds lockblock maxshowndata mineemptyrounds miningrequirespeers miningturnover.
getinfo Returns general information about this node and blockchain. MultiChain adds some fields to Bitcoin Core’s response, giving the blockchain’s chainname, description, protocol, peer-to-peer port. There are also incomingpaused and miningpaused fields – see the pause command. The burnaddress is an address with no known private key, to which assets can be sent to make them provably unspendable. The nodeaddress can be passed to other nodes for connecting. The setupblocks field gives the length in blocks of the setup phase in which some consensus constraints are not applied.
help Returns a list of available API commands, including MultiChain-specific commands.
stop Shuts down the this blockchain node, i.e. stops the multichaind process.
Managing wallet addresses
addmultisigaddress nrequired ["key", ...] Creates a pay-to-scripthash (P2SH) multisig address and adds it to the wallet. Funds sent to this address can only be spent by transactions signed by nrequired of the specified keys. Each key can be a full public key, or an address if the corresponding key is in the node’s wallet. (Public keys for a wallet’s addresses can be obtained using the getaddresses call with verbose=true.) Returns the P2SH address.
getaddresses (verbose=false) Returns a list of addresses in this node’s wallet. Set verbose to true to get more information about each address, formatted like the output of the validateaddress command. For more control see the new listaddresses command.
getnewaddress Returns a new address whose private key is added to the wallet.
importaddress address(es) (label)
(rescan=true)
Adds address (or a full public key, or an array of either) to the wallet, without an associated private key. This creates one or more watch-only addresses, whose activity and balance can be retrieved via various APIs (e.g. with the includeWatchOnly parameter), but whose funds cannot be spent by this node. If rescan is true, the entire blockchain is checked for transactions relating to all addresses in the wallet, including the added ones. Returns null if successful.
listaddresses (addresses=*) (verbose=false)
(count=MAX) (start=-count)
Returns information about the addresses in the wallet. Provide one or more addresses (comma-delimited or as an array) to retrieve information about specific addresses only, or use * for all addresses in the wallet. Use count and start to retrieve part of the list only, with negative start values (like the default) indicating the most recently created addresses.
Working with non-wallet addresses
createkeypairs (count=1) Generates one or more public/private key pairs, which are not stored in the wallet or drawn from the node’s key pool, ready for external key management. For each key pair, the address, pubkey (as embedded in transaction inputs) and privkey (used for signatures) is provided.
createmultisig nrequired
["key", ...]
Creates a pay-to-scripthash (P2SH) multisig address. Funds sent to this address can only be spent by transactions signed by nrequired of the specified keys. Each key can be a full hexadecimal public key, or an address if the corresponding key is in the node’s wallet. Returns an object containing the P2SH address and corresponding redeem script.
validateaddress address Returns information about address including a check for its validity.
Permissions management
grant addresses permissions
(native-amount=0)
(start-block) (end-block)
(comment) (comment-to)
Grants permissions to addresses, a comma-separated list of addresses. For global permissions, set permissions to one of connect, send, receive, create, issue, mine, activate, admin, or a comma-separated list thereof. For per-asset or per-stream permissions, use the form entity.issue or entity.write,admin where entity is an asset or stream name, ref or creation txid. If the chain uses a native currency, you can send some to each recipient using the native-amount parameter. Returns the txid of the transaction granting the permissions. For more information, see permissions management.
grantfrom from-address to-addresses
permissions (native-amount=0)
(start-block) (end-block)
(comment) (comment-to)
This works like grant, but with control over the from-address used to grant the permissions. It is useful if the node has multiple addresses with administrator permissions.
grantwithdata
or grantwithmetadata
addresses permissions
data-hex|object
(native-amount=0)
(start-block) (end-block)
This works like grant, but with an additional data-only transaction output. To include raw data, pass a data-hex hexadecimal string. To publish the data to a stream, pass an object {"for":stream,"key":"...","data":"..."} where stream is a stream name, ref or creation txid, the key is in text form, and the data is hexadecimal.
grantwithdatafrom
or grantwithmetadatafrom
from-address to-addresses
permissions data-hex|object
(native-amount=0)
(start-block) (end-block)
This works like grantwithdata, but with control over the from-address used to grant the permissions.
listpermissions (permissions=*)
(addresses=*)
(verbose=false)
Returns a list of all permissions which have been explicitly granted to addresses. To list information about specific global permissions, set permissions to one of connect, send, receive, issue, mine, activate, admin, or a comma-separated list thereof. Omit or pass * or all to list all global permissions. For per-asset or per-stream permissions, use the form entity.issue, entity.write,admin or entity.* where entity is an asset or stream name, ref or creation txid. Provide a comma-delimited list in addresses to list the permissions for particular addresses or * for all addresses. If verbose is true, the admins output field lists the administrator/s who assigned the corresponding permission, and the pending field lists permission changes which are waiting to reach consensus.
revoke addresses permissions
(native-amount=0)
(comment) (comment-to)
Revokes permissions from addresses, a comma-separated list of addresses. The permissions parameter works the same as for grant. This is equivalent to calling grant with start-block=0 and end-block=0. Returns the txid of transaction revoking the permissions. For more information, see permissions management.
revokefrom from-address to-addresses
permissions (native-amount=0)
(comment) (comment-to)
This works like revoke, but with control over the from-address used to revoke the permissions. It is useful if the node has multiple addresses with administrator permissions.
Asset management
issue address name|params
qty (units=1)
(native-amount=min-per-output)
({"custom-field-1":"x",...})
Creates a new asset on the blockchain, sending the initial qty units to address. To create an asset with the default behavior, use an asset name only for name|params. For more control, use an object such as {"name":"asset1","open":true}. If open is true then additional units can be issued in future by the same key which signed the original issuance, via the issuemore or issuemorefrom command. The smallest transactable unit is given by units, e.g. 0.01. If the chain uses a native currency, you can send some with the new asset using the native-amount parameter. Returns the txid of the issuance transaction. For more information, see native assets.
issuefrom from-address to-address
name|params qty (units=1)
(native-amount=min-per-output)
({"custom-field-1":"x",...})
This works like issue, but with control over the from-address used to issue the asset. It is useful if the node has multiple addresses with issue permissions.
issuemore address asset qty
(native-amount=min-per-output)
({"custom-field-1":"x",...})
Issues qty additional units of asset, sending them to address. The asset can be specified using its name, ref or issuance txid – see native assets for more information. If the chain uses a native currency, you can send some with the new asset units using the native-amount parameter. Any custom fields will be attached to the new issuance event, and not affect the original values (use listassets with verbose=true to see both sets). Returns the txid of the issuance transaction.
issuemorefrom from-address to-address
asset qty
(native-amount=min-per-output)
({"custom-field-1":"x",...})
This works like issuemore, but with control over the from-address used.
listassets (assets=*) (verbose=false)
(count=MAX) (start=-count)
Returns information about assets issued on the blockchain. Pass an asset name, ref or issuance txid in assets to retrieve information about one asset only, an array thereof for multiple assets, or * for all assets. In assets with multiple issuance events, the top-level issuetxid and details fields refer to the first issuance only – set verbose to true for details about each of the individual issuances. Use count and start to retrieve part of the list only, with negative start values (like the default) indicating the most recently created assets. Extra fields are shown for assets to which this node is subscribed.
Querying wallet balances and transactions

getaddressbalances address (minconf=1)
(includeLocked=false)
Returns a list of all the asset balances for address in this node’s wallet, with at least minconf confirmations. Use includeLocked to include unspent outputs which have been locked, e.g. by a call to preparelockunspent.
getaddresstransaction address txid
(verbose=false)
Provides information about transaction txid related to address in this node’s wallet, including how it affected that address’s balance. Use verbose to provide details of transaction inputs and outputs.
getmultibalances (addresses=*)
(assets=*)
(minconf=1)
(includeWatchOnly=false)
(includeLocked=false)
Returns a list of balances of the addresses in this node’s wallet for the specified assets, with at least minconf confirmations. The addresses are specified as a comma-delimited list or array, or * for all addresses with non-zero balances. The assets are specified as an array of asset names, refs or issuance txids, or * for all assets with non-zero balances. Use includeWatchOnly to include watch-only addresses (only relevant if addresses=*) and includeLocked to include unspent outputs which have been locked, e.g. by a call to preparelockunspent. The response includes a total of the balances shown.
gettotalbalances (minconf=1)
(includeWatchOnly=false)
(includeLocked=false)
Returns a list of all the asset balances in this node’s wallet, with at least minconf confirmations. Use includeWatchOnly to include the balance of watch-only addresses and includeLocked to include unspent outputs which have been locked, e.g. by a call to preparelockunspent.
getwallettransaction txid
(includeWatchOnly=false)
(verbose=false)
Provides information about transaction txid in this node’s wallet, including how it affected the node’s total balance. Use includeWatchOnly to consider watch-only addresses as if they belong to this wallet and verbose to provide details of transaction inputs and outputs.
listaddresstransactions address
(count=10) (skip=0)
(verbose=false)
Lists information about the count most recent transactions related to address in this node’s wallet, including how they affected that address’s balance. Use skip to go back further in history and verbose to provide details of transaction inputs and outputs.
listwallettransactions (count=10) (skip=0)
(includeWatchOnly=false)
(verbose=false)
Lists information about the count most recent transactions in this node’s wallet, including how they affected the node’s total balance. Use skip to go back further in history and includeWatchOnly to consider watch-only addresses as if they belong to this wallet. Use verbose to provide the details of transaction inputs and outputs. Note that unlike Bitcoin Core’s listtransactions command, the response contains one element per transaction, rather than one per transaction output.
Sending one-way payments
send
or sendtoaddress
address amount
(comment)
(comment-to)
Sends one or more assets to address, returning the txid. In Bitcoin Core, the amount field is the quantity of the bitcoin currency. For MultiChain, an {"asset":qty, ...} object can be used for amount, in which each asset is an asset name, ref or issuance txid, and each qty is the quantity of that asset to send (see native assets). Use "" as the asset inside this object to specify a quantity of the native blockchain currency. See also sendasset for sending a single asset and sendfrom to control the address whose funds are used.
sendasset
or sendassettoaddress
address asset qty
(native-amount=min-per-output)
(comment) (comment-to)
Sends qty of asset to address, returning the txid. The asset can be specified using its name, ref or issuance txid – see native assets for more information. See also sendassetfrom to control the address whose funds are used, send for sending multiple assets in one transaction, and sendfrom to combine both of these.
sendassetfrom from-address to-address
asset qty
(native-amount=min-per-output)
(comment) (comment-to)
This works like sendasset, but with control over the from-address whose funds are used. Any change from the transaction is sent back to from-address. See also sendfrom for sending multiple assets in one transaction.
sendfrom
or sendfromaddress
from-address to-address amount
(comment) (comment-to)
This works like send, but with control over the from-address whose funds are used. Any change from the transaction is sent back to from-address.
sendwithdata
or sendwithmetadata
address amount data-hex|object This works like send, but with an additional data-only transaction output. To include raw data, pass a data-hex hexadecimal string. To publish the data to a stream, pass an object {"for":stream,"key":"...","data":"..."} where stream is a stream name, ref or creation txid, the key is in text form, and the data is hexadecimal.
sendwithdatafrom
or sendwithmetadatafrom
from-address to-address
amount data-hex|object
This works like sendwithdata, but with control over the from-address whose funds are used. Any change from the transaction is sent back to from-address.
Atomic exchange transactions
appendrawexchange tx-hex txid vout
{"asset":qty, ...}
Adds to the raw atomic exchange transaction in tx-hex given by a previous call to createrawexchange or appendrawexchange. This adds an offer to exchange the asset/s in output vout of transaction txid for qty units of asset, where asset is an asset name, ref or issuance txid. The txid and vout should generally be taken from preparelockunspent or preparelockunspentfrom. Multiple items can be specified within the fourth parameter to request multiple assets. Returns a raw transaction in the hex field alongside a complete field stating whether the exchange is complete (i.e. balanced) or not. If complete, the transaction can be broadcast to the network using sendrawtransaction. If not, it can be passed to a further counterparty, who can call decoderawexchange and appendrawexchange as appropriate.
completerawexchange tx-hex txid vout
{"asset":qty, ...}
(data-hex|object)
This works like appendrawexchange but finalizes the exchange, preventing any further additions. (Technically, it adds a SIGHASH_ALL signature.) If the completed exchange is not balanced, an error is returned. Optional metadata can be added to the transaction, signed by this user only. To include raw data, pass a data-hex hexadecimal string. To publish the data to a stream, pass an object {"for":stream,"key":"...","data":"..."} where stream is a stream name, ref or creation txid, the key is in text form, and the data is hexadecimal. Returns a raw transaction in hexadecimal which can be broadcast to the network using sendrawtransaction.
createrawexchange txid vout
{"asset":qty, ...}
Creates a new atomic exchange transaction which offers to exchange the asset/s in output vout of transaction txid for qty units of asset, where asset is an asset name, ref or issuance txid. The txid and vout should generally be taken from the response to preparelockunspent or preparelockunspentfrom. Multiple items can be specified within the third parameter to request multiple assets. Returns a raw partial transaction in hexadecimal which can be passed to the counterparty, who can call decoderawexchange and appendrawexchange as appropriate.
decoderawexchange tx-hex
(verbose=false)
Decodes the raw exchange transaction in tx-hex, given by a previous call to createrawexchange or appendrawexchange. Returns details on the offer represented by the exchange and its present state. The offer field in the response lists the quantity of native currency and/or assets which are being offered for exchange. The ask field lists the native currency and/or assets which are being asked for. The candisable field specifies whether this wallet can disable the exchange transaction by double-spending against one of its inputs. The cancomplete field specifies whether this wallet has the assets required to complete the exchange. The complete field specifies whether the exchange is already complete (i.e. balanced) and ready for sending. If verbose is true then all of the individual stages in the exchange are listed. Other fields relating to fees are only relevant for blockchains which use a native currency.
disablerawtransaction tx-hex Sends a transaction to disable the offer of exchange in tx-hex, returning the txid. This is achieved by spending one of the exchange transaction’s inputs and sending it back to the wallet. To check whether this can be used on an exchange transaction, check the candisable field of the output of decoderawexchange.
preparelockunspent {"asset":qty, ...}
(lock=true)
Prepares an unspent transaction output (useful for building atomic exchange transactions) containing qty units of asset, where asset is an asset name, ref or issuance txid. Multiple items can be specified within the first parameter to include several assets within the output. The output will be locked against automatic selection for spending unless the optional lock parameter is set to false. Returns the txid and vout of the prepared output.
preparelockunspentfrom from-address
{"asset":qty, ...}
(lock=true)
This works like preparelockunspent, but with control over the from-address whose funds are used to prepare the unspent transaction output. Any change from the transaction is send back to from-address.
Stream management
create type=stream name open
({"custom-field-1":"x",...})
Creates a new stream on the blockchain called name. For now, always pass the value "stream" in the type parameter – this is designed for future functionality. If open is true then anyone with global send permissions can publish to the stream, otherwise publishers must be explicitly granted per-stream write permissions.
createfrom from-address
type=stream name open
({"custom-field-1":"x",...})
This works like create, but with control over the from-address used to create the stream. It is useful if the node has multiple addresses with create permissions.
liststreams (streams=*) (verbose=false)
(count=MAX) (start=-count)
Returns information about streams created on the blockchain. Pass a stream name, ref or creation txid in streams to retrieve information about one stream only, an array thereof for multiple streams, or * for all streams. Use count and start to retrieve part of the list only, with negative start values (like the default) indicating the most recently created streams. Extra fields are shown for streams to which this node has subscribed.
Publishing stream items
publish stream key data-hex Publishes an item in stream, passed as a stream name, ref or creation txid, with key provided in text form and data-hex in hexadecimal.
publishfrom from-address
stream key data-hex
This works like publish, but publishes the item from from-address. It is useful if a stream is open or the node has multiple addresses with per-stream write permissions.
Managing stream and asset subscriptions
subscribe asset(s)|stream(s)
(rescan=true)
Instructs the node to start tracking one or more asset(s) or stream(s). These are specified using a name, ref or creation/issuance txid, or for multiple items, an array thereof. If rescan is true, the node will reindex all items from when the assets and/or streams were created, as well as those in other subscribed entities. Returns null if successful. See also the autosubscribe runtime parameter.
unsubscribe asset(s)|stream(s) Instructs the node to stop tracking one or more asset(s) or stream(s). Assets or streams are specified using a name, ref or creation/issuance txid, or for multiple items, an array thereof.
Querying subscribed assets
getassettransaction asset txid
(verbose=false)
Retrieves a specific transaction txid involving asset, passed as an asset name, ref or issuance txid, to which the node must be subscribed. Set verbose to true for additional information about the transaction.
listassettransactions asset (verbose=false)
(count=10) (start=-count)
(local-ordering=false)
Lists transactions involving asset, passed as an asset name, ref or issuance txid, to which the node must be subscribed. Set verbose to true for additional information about each transaction. Use count and start to retrieve part of the list only, with negative start values (like the default) indicating the most recent items. Set local-ordering to true to order transactions by when first seen by this node, rather than their order in the chain.
Querying subscribed streams
getstreamitem stream txid
(verbose=false)
Retrieves a specific item with txid from stream, passed as a stream name, ref or creation txid, to which the node must be subscribed. Set verbose to true for additional information about the item’s transaction. If an item’s data is larger than the maxshowndata runtime parameter, it will be returned as an object whose fields can be used with gettxoutdata.
gettxoutdata txid vout
(count-bytes=INT_MAX)
(start-byte=0)
Returns the data embedded in output vout of transaction txid, in hexadecimal. This is particularly useful if a stream item’s data is larger than the maxshowndata runtime parameter. Use the count-bytes and start-byte parameters to retrieve part of the data only.
liststreamkeyitems stream key (verbose=false)
(count=10) (start=-count)
(local-ordering=false)
This works like liststreamitems, but listing items with the given key only.
liststreamkeys stream (keys=*)
(verbose=false)
(count=MAX) (start=-count)
(local-ordering=false)
Provides information about keys in stream, passed as a stream name, ref or creation txid. Pass a single key in keys to retrieve information about one key only, pass an array for multiple keys, or * for all keys. Set verbose to true to include information about the first and last item with each key shown. See liststreamitems for details of the count, start and local-ordering parameters.
liststreamitems stream (verbose=false)
(count=10) (start=-count)
(local-ordering=false)
Lists items in stream, passed as a stream name, ref or creation txid. Set verbose to true for additional information about each item’s transaction. Use count and start to retrieve part of the list only, with negative start values (like the default) indicating the most recent items. Set local-ordering to true to order items by when first seen by this node, rather than their order in the chain. If an item’s data is larger than the maxshowndata runtime parameter, it will be returned as an object whose fields can be used with gettxoutdata.
liststreampublisheritems stream address
(verbose=false)
(count=10) (start=-count)
(local-ordering=false)
This works like liststreamitems, but listing items published by the given address only.
liststreampublishers stream (addresses=*)
(verbose=false)
(count=MAX) (start=-count)
(local-ordering=false)
Provides information about publishers who have written to stream, passed as a stream name, ref or creation txid. Pass a single address in addresses to retrieve information about one publisher only, pass an array or comma-delimited list for multiple publishers, or * for all publishers. Set verbose to true to include information about the first and last item by each publisher shown. See liststreamitems for details of the count, start and local-ordering parameters, relevant only if address=*.
Managing wallet unspent outputs
combineunspent (addresses=*) (minconf=1)
(maxcombines=1) (mininputs=10)
(maxinputs=100) (maxtime=30)
Sends transactions to combine unspent outputs (UTXOs) belonging to the same address into a single unspent output, returning a list of txids. This can improve wallet performance, especially for miners in a chain with short block times and non-zero block rewards. Set addresses to a comma-separated list of addresses to combine outputs for, or * for all addresses in the wallet. Only combines outputs with at least minconf confirmations, using between mininputs and maxinputs per transaction. A single call to combineunspent can create up to maxcombines transactions over up to maxtime seconds. See also the autocombine runtime parameters.
listlockunspent Returns a list of locked unspent transaction outputs in the wallet. These will not be used when automatically selecting the outputs to spend in a new transaction.
listunspent (minconf=1) (maxconf=999999)
(["address", ...])
Returns a list of unspent transaction outputs in the wallet, with between minconf and maxconf confirmations. For a MultiChain blockchain, each transaction output includes assets and permissions fields listing any assets or permission changes encoded within that output. If the third parameter is provided, only outputs which pay an address in this array will be included.
lockunspent unlock
([{"txid":"id","vout":n},...])
If unlock is false, locks the specified transaction outputs in the wallet, so they will not be used for automatic coin selection. If unlock is true, it unlocks the specified outputs, or unlocks all outputs if no second parameter is provided.
Working with raw transactions
appendrawchange tx-hex address
(native-fee)
Adds a change output to the raw transaction in tx-hex given by a previous call to createrawtransaction. Any assets or native currency in the transaction inputs which are not claimed in the outputs will be sent to address, minus the native-fee (which is calculated automatically if omitted). The returned raw transaction can be signed and broadcast to the network using signrawtransaction and sendrawtransaction.
appendrawdata
or appendrawmetadata
tx-hex data-hex|object Adds a metadata output (using an OP_RETURN) to the raw transaction in tx-hex given by a previous call to createrawtransaction. Raw metadata can be specified in data-hex in hexadecimal form. Alternatively, an object can be passed to represent asset issuance, stream creation or a stream item – see raw transactions for more details. The returned raw transaction can be signed and broadcast to the network using signrawtransaction and sendrawtransaction.
createrawtransaction [{"txid":"id","vout":n},...]
{"address":amount,...}
(data=[]) (action="")
Creates a transaction spending the specified inputs, sending to the given addresses. In Bitcoin Core, each amount field is a quantity of the bitcoin currency. For MultiChain, an {"asset":qty, ...} object can be used for amount, in which each asset is an asset name, ref or issuance txid, and each qty is the quantity of that asset to send (see native assets). Use "" as the asset inside this object to specify a quantity of the native blockchain currency. The optional data array adds one or more metadata outputs to the transaction, where each element is a raw hexadecimal string or object, formatted as passed to appendrawdata. The optional action parameter can be lock (locks the given inputs in the wallet), sign (signs the transaction using wallet keys), lock,sign (does both) or send (signs and sends the transaction). If action is send the txid is returned. If action contains sign, an object with hex and complete fields is returned, as for signrawtransaction. Otherwise, the raw transaction hexadecimal is returned. See raw transactions for more details on building raw transactions.
createrawsendfrom from-address
{"to-address":amount,...}
(data=[]) (action="")
This works like createrawtransaction, except it automatically selects the transaction inputs from those belonging to from-address, to cover the appropriate amounts. One or more change outputs going back to from-address will also be added to the end of the transaction.
decoderawtransaction tx-hex Returns a JSON object describing the serialized transaction in tx-hex. For a MultiChain blockchain, each transaction output includes assets and permissions fields listing any assets or permission changes encoded within that output. There will also be a data field listing the content of any OP_RETURN outputs in the transaction.
sendrawtransaction tx-hex Validates the raw transaction in tx-hex and transmits it to the network, returning the txid. The raw transaction can be created using createrawtransaction, (optionally) appendrawdata and signrawtransaction, or else createrawexchange and appendrawexchange.
signrawtransaction tx-hex
([{parent-output},...])
(["private-key",...])
(sighashtype=ALL)
Signs the raw transaction in tx-hex, often provided by a previous call to createrawtransaction or createrawsendfrom. Returns a raw hexadecimal transaction in the hex field alongside a complete field stating whether it is now completely signed. If complete, the transaction can be broadcast to the network using sendrawtransaction. If not, it can be passed to other parties for additional signing. To create chains of unbroadcast transactions, pass an optional array of {parent-output} objects, each of which takes the form {"txid":txid,"vout":n,"scriptPubKey":hex}. To sign using (only) private keys which are not in the node’s wallet, pass an array of "private-key" strings, formatted as per the output of dumpprivkey. To sign only part of the transaction, use the sighashtype parameter to control the signature hash type.
Peer-to-peer connections
addnode ip(:port)
command
Manually adds or removes a peer-to-peer connection (peers are also discovered and added automatically). The ip can be a hostname, IPv4 address, IPv4-as-IPv6 address or IPv6 address. For the entire ip:port you can also use the part after the @ symbol of the other node’s nodeaddress, as given by the getinfo command. The command parameter should be one of add (to manually queue a node for the next available slot), remove (to remove a node), or onetry (to immediately connect to a node even if a slot is not available).
getaddednodeinfo verbose (ip(:port)) If verbose=true, returns information about a node which was added using addnode, or all such nodes if ip(:port) is omitted. If verbose=false, returns a list of added nodes only.
getnetworkinfo Returns information about the network ports to which the node is connected, and its local IP addresses.
getpeerinfo Returns information about the other nodes to which this node is connected. If this is a MultiChain blockchain, includes handshake and handshakelocal fields showing the remote and local address used during the handshaking for that connection.
ping Sends a ping message to all connected nodes to measure network latency and backlog. The results are received asynchronously and retrieved from the pingtime field of the response to getpeerinfo.
Messaging signing and verification
signmessage address message Returns a base64-encoded digital signature which proves that message was approved by the owner of address (which must belong to this wallet). The signature can be verified by any node using the verifymessage command.
verifymessage address signature
message
Verifies that message was approved by the owner of address by checking the base64-encoded digital signature provided by a previous call to signmessage. The result is true or false unless an error occurred.
Querying the blockchain
getblock hash|height
(verbose=1)
Returns information about the block with hash (retrievable from getblockhash) or at the given height in the active chain. Set verbose to 0 or false for the block in raw hexadecimal form. Set to 1 or true for a block summary including the miner address and a list of txids. Set to 2 to 3 to include more information about each transaction and its raw hexadecimal. Set to 4 to include a full description of each transaction, formatted like the output of decoderawtransaction.
getblockchaininfo Returns information about the blockchain, including the bestblockhash of the most recent block on the active chain, which can be compared across nodes to check if they are perfectly synchronized.
getblockhash height Returns the hash of the block at the given height. This can be passed to getblock to get information about the block.
getmempoolinfo Returns information about the memory pool, which contains transactions that the node has seen and validated, but which have not yet been confirmed on the active chain. If the memory pool is growing continuously, this suggests that transactions are being generated faster than the network is able to process them.
getrawmempool Returns a list of transaction IDs which are in the node’s memory pool (see getmempoolinfo).
getrawtransaction txid (verbose=0) If verbose is 1, returns a JSON object describing transaction txid. For a MultiChain blockchain, each transaction output includes assets and permissions fields listing any assets or permission changes encoded within that output. There will also be a data field listing the content of any OP_RETURN outputs in the transaction.
gettxout txid vout
(unconfirmed=false)
Returns details about an unspent transaction output vout of txid. For a MultiChain blockchain, includes assets and permissions fields listing any assets or permission changes encoded within the output. Set unconfirmed to true to include unconfirmed transaction outputs.
Advanced wallet control
backupwallet filename Creates a backup of the wallet.dat file in which the node’s private keys and watch-only addresses are stored. The backup is created in file filename. Use with caution – any node with access to this file can perform any action restricted to this node’s addresses.
dumpprivkey address Returns the private key associated with address in this node’s wallet. Use with caution – any node with access to this private key can perform any action restricted to the address.
dumpwallet filename Dumps the entire set of private keys in the wallet into a human-readable text format in file filename. Use with caution – any node with access to this file can perform any action restricted to this node’s addresses.
encryptwallet passphrase This encrypts the node’s wallet for the first time, using passphrase as the password for unlocking. Once encryption is complete, the wallet’s private keys can no longer be retrieved directly from the wallet.dat file on disk, and MultiChain will stop and need to be restarted. Use with caution – once a wallet has been encrypted it cannot be permanently unencrypted, and must be unlocked for signing transactions with the walletpassphrase command. In a permissioned blockchain, MultiChain will also require the wallet to be unlocked before it can connect to other nodes, or sign blocks that it has mined.
getwalletinfo Returns information about the node’s wallet, including the number of transactions (txcount) and unspent transaction outputs (utxocount), the pool of pregenerated keys. If the wallet has been encrypted and unlocked, it also shows when it is unlocked_until.
importprivkey privkey(s) (label)
(rescan=true)
Adds a privkey private key (or an array thereof) to the wallet, together with its associated public address. If rescan is true, the entire blockchain is checked for transactions relating to all addresses in the wallet, including the added ones. Returns null if successful.
importwallet filename Imports the entire set of private keys which were previously dumped (using dumpwallet) into file filename. The entire blockchain will be rescanned for transactions relating to the addresses corresponding with these private keys.
walletlock This immediately relocks the node’s wallet, independent of the timeout provided by a previous call to walletpassphrase.
walletpassphrase passphrase timeout This uses passphrase (as set in earlier calls to encryptwallet or walletpassphrasechange) to unlock the node’s wallet for signing transactions for the next timeout seconds. In a permissioned blockchain, this will also need to be called before the node can connect to other nodes or sign blocks that it has mined.
walletpassphrasechange old-passphrase
new-passphrase
This changes the wallet’s password from old-passphrase to new-passphrase.
Advanced node control
clearmempool Removes all unconfirmed transactions from this node’s memory pool. This can only be called after pause incoming,mining. Successful if no error is returned.
pause tasks Pauses the specified tasks, specified as a comma-delimited list of mining (i.e. generating blocks) and/or incoming (i.e. processing of incoming blocks and transactions). Successful if no error is returned.
resume tasks Resumes the specified tasks, specified as in the pause command. Successful if no error is returned.
setlastblock hash|height Rewinds this node’s active chain to height or rewinds/switches to another block with hash. This can only be called after pause incoming,mining. Returns the hash of the last block in the chain after the change.

A note about accounts

Bitcoin Core has a notion of “accounts”, whereby each address can belong to specific account, which is credited when bitcoin is sent to that address. However the separation of accounts is not preserved when bitcoin is sent out, because the internal accounting mechanism has no relationship to the bitcoin protocol itself. Because of all the confusion this has caused, Bitcoin Core’s accounts mechanism is to be deprecated in future.

As of alpha 22, MultiChain no longer supports Bitcoin Core’s account APIs, if you are using the new wallet version which is activated by default (walletdbversion=2 in the output from getinfo). This includes the commands: getaccount getaccountaddress getreceivedbyaccount listreceivedbyaccount move sendfrom sendmany setaccount. In addition it only supports an empty value for the account parameter of: addmultisigaddress getaddressesbyaccount getbalance getnewaddress. If you are using the old wallet version, MultiChain preserves full backwards compatibility with the Bitcoin Core API, but (a) sendfrom is renamed to sendfromaccount, and (b) the accounts mechanism is not applied to native asset balances, all of which are considered as belonging to a single global account.

Overall we recommend not using accounts at all with MultiChain, and using "" for any account parameter in the API. Instead, to support multiple users in a single MultiChain node’s wallet, call getnewaddress to get a different address for each user. You should then use MultiChain’s from APIs, such as sendassetfrom and sendfrom, to control whose funds are spent in each transaction. Unlike bitcoin-style accounts, this method maps directly to the blockchain protocol.