-
createCompositeKey(objectType, attributes)
-
Creates a composite key by combining the objectType string and the given `attributes` to form a composite
key. The objectType and attributes are expected to have only valid utf8 strings and should not contain
U+0000 (nil byte) and U+10FFFF (biggest and unallocated code point). The resulting composite key can be
used as the key in putState().
Hyperledger Fabric uses a simple key/value model for saving chaincode states. In some use case scenarios,
it is necessary to keep track of multiple attributes. Furthermore, it may be necessary to make the various
attributes searchable. Composite keys can be used to address these requirements. Similar to using composite
keys in a relational database table, here you would treat the searchable attributes as key columns that
make up the composite key. Values for the attributes become part of the key, thus they are searchable with
functions like getStateByRange() and
getStateByPartialCompositeKey().
Parameters:
| Name |
Type |
Description |
objectType |
string
|
A string used as the prefix of the resulting key |
attributes |
Array.<string>
|
List of attribute values to concatenate into the key |
Returns:
A composite key with the objectType and the array of attributes
joined together with special delimiters that will not be confused with values of the attributes
-
Type
-
string
-
<async> deletePrivateData(collection, key)
-
deletePrivateData records the specified `key` to be deleted in the private writeset of
the transaction. Note that only hash of the private writeset goes into the
transaction proposal response (which is sent to the client who issued the
transaction) and the actual private writeset gets temporarily stored in a
transient store. The `key` and its value will be deleted from the collection
when the transaction is validated and successfully committed.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
key |
string
|
Private data variable key to delete from the state store |
-
<async> deleteState(key)
-
Deletes the state variable key from the state store.
Parameters:
| Name |
Type |
Description |
key |
string
|
State variable key to delete from the state store |
Returns:
Promise will be resolved when the peer has successfully handled the state delete request
or rejected if any errors
-
Type
-
Promise
-
getArgs()
-
Returns the arguments as array of strings from the chaincode invocation request.
Equivalent to getStringArgs()
Returns:
-
Type
-
Array.<string>
-
getBinding()
-
Returns a HEX-encoded string of SHA256 hash of the transaction's nonce, creator and epoch concatenated, as a
unique representation of the specific transaction. This value can be used to prevent replay attacks in chaincodes
that need to authenticate an identity independent of the transaction's submitter. In a chaincode proposal, the
submitter will have been authenticated by the peer such that the identity returned by
stub.getCreator() can be trusted. But in some scenarios, the chaincode needs
to authenticate an identity independent of the proposal submitter.
For example, Alice is the administrator who installs and instantiates a chaincode that manages assets. During
instantiate Alice assigns the initial owner of the asset to Bob. The chaincode has a function called
transfer() that moves the asset to another identity by changing the asset's "owner" property to the
identity receiving the asset. Naturally only Bob, the current owner, is supposed to be able to call that function.
While the chaincode can rely on stub.getCreator() to check the submitter's identity and compare that with the
current owner, sometimes it's not always possible for the asset owner itself to submit the transaction. Let's suppose
Bob hires a broker agency to handle his trades. The agency participates in the blockchain network and carry out trades
on behalf of Bob. The chaincode must have a way to authenticate the transaction to ensure it has Bob's authorization
to do the asset transfer. This can be achieved by asking Bob to sign the message, so that the chaincode can use
Bob's certificate, which was obtained during the chaincode instantiate, to verify the signature and thus ensure
the trade was authorized by Bob.
Now, to prevent Bob's signature from being re-used in a malicious attack, we want to ensure the signature is unique.
This is where the binding concept comes in. As explained above, the binding string uniquely represents
the transaction where the trade proposal and Bob's authorization is submitted in. As long as Bob's signature is over
the proposal payload and the binding string concatenated together, namely sigma=Sign(BobSigningKey, tx.Payload||tx.Binding),
it's guaranteed to be unique and can not be re-used in a different transaction for exploitation.
Returns:
A HEX-encoded string of SHA256 hash of the transaction's nonce, creator and epoch concatenated
-
Type
-
string
-
getChannelID()
-
Returns the channel ID for the proposal for chaincode to process.
This would be the 'channel_id' of the transaction proposal (see ChannelHeader
in protos/common/common.proto) except where the chaincode is calling another on
a different channel.
-
getCreator()
-
Returns the identity object of the chaincode invocation's submitter
Returns:
-
Type
-
ProposalCreator
-
getDateTimestamp()
-
Returns the Date object of when the transaction was created. This
is taken from the transaction ChannelHeader, therefore it will indicate the
client's date, and will have the same value across all endorsers.
-
getFunctionAndParameters()
-
Returns an object containing the chaincode function name to invoke, and the array
of arguments to pass to the target function
Returns:
-
Type
-
FunctionAndParameters
-
<async> getHistoryForKey(key)
-
Returns a history of key values across time.
For each historic key update, the historic value and associated
transaction id and timestamp are returned. The timestamp is the
timestamp provided by the client in the proposal header.
This method requires peer configuration
core.ledger.history.enableHistoryDatabase to be true.
The query is NOT re-executed during validation phase, phantom reads are
not detected. That is, other committed transactions may have updated
the key concurrently, impacting the result set, and this would not be
detected at validation/commit time. Applications susceptible to this
should therefore not use GetHistoryForKey as part of transactions that
update ledger, and should limit use to read-only chaincode operations.
Parameters:
| Name |
Type |
Description |
key |
string
|
The state variable key |
Returns:
Promise for a HistoryQueryIterator object
-
Type
-
Promise
-
getMspID()
-
Returns the MSPID of the peer that started this chaincode
Returns:
MSPID
-
Type
-
string
-
<async> getPrivateData(collection, key)
-
getPrivateData returns the value of the specified `key` from the specified
`collection`. Note that GetPrivateData doesn't read data from the
private writeset, which has not been committed to the `collection`. In
other words, GetPrivateData doesn't consider data modified by PutPrivateData
that has not been committed.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
key |
string
|
Private data variable key to retrieve from the state store |
Returns:
Promise for the private value from the state store
-
Type
-
Promise.<Array.<byte>>
-
getPrivateDataByPartialCompositeKey(collection, objectType, attributes)
-
getPrivateDataByPartialCompositeKey queries the state in a given private
collection based on a given partial composite key. This function returns
an iterator which can be used to iterate over all composite keys whose prefix
matches the given partial composite key. The `objectType` and attributes are
expected to have only valid utf8 strings and should not contain
U+0000 (nil byte) and U+10FFFF (biggest and unallocated code point).
See related functions SplitCompositeKey and CreateCompositeKey.
Call Close() on the returned StateQueryIteratorInterface object when done.
The query is re-executed during validation phase to ensure result set
has not changed since transaction endorsement (phantom reads detected).
This function should be used only for a partial composite key.
For a full composite key, an iter with empty response would be returned.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
objectType |
string
|
A string used as the prefix of the resulting key |
attributes |
Array.<string>
|
List of attribute values to concatenate into the partial composite key |
Returns:
Promise for a PrivateQueryResponse object
-
Type
-
Promise
-
getPrivateDataByRange(collection, startKey, endKey)
-
getPrivateDataByRange returns a range iterator over a set of keys in a
given private collection. The iterator can be used to iterate over all keys
between the startKey (inclusive) and endKey (exclusive).
The keys are returned by the iterator in lexical order. Note
that startKey and endKey can be empty string, which implies unbounded range
query on start or end.
Call Close() on the returned StateQueryIteratorInterface object when done.
The query is re-executed during validation phase to ensure result set
has not changed since transaction endorsement (phantom reads detected).
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
startKey |
string
|
Private data variable key as the start of the key range (inclusive) |
endKey |
string
|
Private data variable key as the end of the key range (exclusive) |
Returns:
Promise for a PrivateQueryResponse object
-
Type
-
Promise
-
<async> getPrivateDataHash(collection, key)
-
getPrivateDataHash returns the hash of the value of the specified `key` from
the specified `collection`.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
key |
string
|
Private data variable key to retrieve a hash from the state store |
Returns:
Promise for the private value hash from the state store
-
Type
-
Promise.<Array.<byte>>
-
getPrivateDataQueryResult(collection, query)
-
getPrivateDataQueryResult performs a "rich" query against a given private
collection. It is only supported for state databases that support rich query,
e.g.CouchDB. The query string is in the native syntax
of the underlying state database. An iterator is returned
which can be used to iterate (next) over the query result set.
The query is NOT re-executed during validation phase, phantom reads are
not detected. That is, other committed transactions may have added,
updated, or removed keys that impact the result set, and this would not
be detected at validation/commit time. Applications susceptible to this
should therefore not use GetQueryResult as part of transactions that update
ledger, and should limit use to read-only chaincode operations.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
query |
string
|
The query to be performed |
Returns:
Promise for a PrivateQueryResponse object
-
Type
-
Promise
-
<async> getPrivateDataValidationParameter(collection, key)
-
GetPrivateDataValidationParameter retrieves the key-level endorsement
policy for the private data specified by `key`. Note that this introduces
a read dependency on `key` in the transaction's readset.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name for this private data |
key |
string
|
Private data variable key by which to retrieve endorsement policy |
Returns:
endorsement policy for this key
-
Type
-
Buffer
-
<async> getQueryResult(query)
-
Performs a "rich" query against a state database. It is
only supported for state databases that support rich query,
e.g. CouchDB. The query string is in the native syntax
of the underlying state database. An StateQueryIterator is returned
which can be used to iterate over all keys in the query result set.
However, if the number of keys in the query result set is greater than the
totalQueryLimit (defined in core.yaml), this iterator cannot be used
to fetch all keys in the query result set (results will be limited by
the totalQueryLimit).
The query is NOT re-executed during validation phase, phantom reads are
not detected. That is, other committed transactions may have added,
updated, or removed keys that impact the result set, and this would not
be detected at validation/commit time. Applications susceptible to this
should therefore not use GetQueryResult as part of transactions that update
ledger, and should limit use to read-only chaincode operations.
Parameters:
| Name |
Type |
Description |
query |
string
|
Query string native to the underlying state database |
Returns:
Promise for a StateQueryIterator object
-
Type
-
Promise
-
-
getQueryResultWithPagination performs a "rich" query against a state database.
It is only supported for state databases that support rich query,
e.g., CouchDB. The query string is in the native syntax
of the underlying state database. An iterator is returned
which can be used to iterate over keys in the query result set.
When an empty string is passed as a value to the bookmark argument, the returned
iterator can be used to fetch the first `pageSize` of query results.
When the bookmark is a non-emptry string, the iterator can be used to fetch
the first `pageSize` keys between the bookmark and the last key in the query result.
Note that only the bookmark present in a prior page of query results (ResponseMetadata)
can be used as a value to the bookmark argument. Otherwise, an empty string
must be passed as bookmark.
This call is only supported in a read only transaction.
Parameters:
| Name |
Type |
Description |
query |
string
|
|
pageSize |
int
|
|
bookmark |
string
|
|
Returns:
Promise for a PaginationQueryResponse object
-
Type
-
Promise
-
getSignedProposal()
-
Returns a fully decoded object of the signed transaction proposal
Returns:
-
Type
-
SignedProposal
-
<async> getState(key)
-
Retrieves the current value of the state variable key
Parameters:
| Name |
Type |
Description |
key |
string
|
State variable key to retrieve from the state store |
Returns:
Promise for the current value of the state variable
-
Type
-
Promise.<Array.<byte>>
-
<async> getStateByPartialCompositeKey(objectType, attributes)
-
Queries the state in the ledger based on a given partial composite key. This function returns an iterator
which can be used to iterate over all composite keys whose prefix matches the given partial composite key.
However, if the number of matching composite keys is greater than the totalQueryLimit (defined in core.yaml),
this iterator cannot be used to fetch all matching keys (results will be limited by the totalQueryLimit).
The `objectType` and attributes are expected to have only valid utf8 strings and should not contain
U+0000 (nil byte) and U+10FFFF (biggest and unallocated code point).
See related functions splitCompositeKey and
createCompositeKey.
Call close() on the returned StateQueryIterator object when done.
The query is re-executed during validation phase to ensure result set has not changed since transaction
endorsement (phantom reads detected).
This function should be used only for a partial composite key.
For a full composite key, an iter with empty response would be returned.
Parameters:
| Name |
Type |
Description |
objectType |
string
|
A string used as the prefix of the resulting key |
attributes |
Array.<string>
|
List of attribute values to concatenate into the partial composite key |
Returns:
A promise that resolves with a StateQueryIterator, rejects if an error occurs
-
Type
-
Promise
-
-
GetStateByPartialCompositeKeyWithPagination queries the state in the ledger based on
a given partial composite key. This function returns an iterator
which can be used to iterate over the composite keys whose
prefix matches the given partial composite key.
When an empty string is passed as a value to the bookmark argument, the returned
iterator can be used to fetch the first `pageSize` composite keys whose prefix
matches the given partial composite key.
When the bookmark is a non-emptry string, the iterator can be used to fetch
the first `pageSize` keys between the bookmark (inclusive) and the last matching
composite key.
Note that only the bookmark present in a prior page of query result (ResponseMetadata)
can be used as a value to the bookmark argument. Otherwise, an empty string must
be passed as bookmark.
The `objectType` and attributes are expected to have only valid utf8 strings
and should not contain U+0000 (nil byte) and U+10FFFF (biggest and unallocated
code point). See related functions SplitCompositeKey and CreateCompositeKey.
Call Close() on the returned StateQueryIteratorInterface object when done.
This call is only supported in a read only transaction.
This function should be used only for a partial composite key.
For a full composite key, an iter with empty response would be returned.
Parameters:
| Name |
Type |
Description |
objectType |
string
|
|
attributes |
Array.<string>
|
|
pageSize |
int
|
|
bookmark |
string
|
|
Returns:
Promise for a PaginationQueryResponse object
-
Type
-
Promise
-
<async> getStateByRange(startKey, endKey)
-
Returns a range iterator over a set of keys in the
ledger. The iterator can be used to iterate over all keys
between the startKey (inclusive) and endKey (exclusive).
However, if the number of keys between startKey and endKey is greater than the
totalQueryLimit (defined in core.yaml, which is the peer's configuration file),
this iterator cannot be used to fetch all keys (results will be limited by the totalQueryLimit).
The keys are returned by the iterator in lexical order. Note
that startKey and endKey can be empty string, which implies unbounded range
query on start or end.
Call close() on the returned StateQueryIterator object when done.
The query is re-executed during validation phase to ensure result set
has not changed since transaction endorsement (phantom reads detected).
Parameters:
| Name |
Type |
Description |
startKey |
string
|
State variable key as the start of the key range (inclusive) |
endKey |
string
|
State variable key as the end of the key range (exclusive) |
Returns:
Promise for a StateQueryIterator object
-
Type
-
Promise
-
-
getStateByRangeWithPagination returns a range iterator over a set of keys in the
ledger. The iterator can be used to fetch keys between the startKey (inclusive)
and endKey (exclusive).
When an empty string is passed as a value to the bookmark argument, the returned
iterator can be used to fetch the first `pageSize` keys between the startKey
(inclusive) and endKey (exclusive).
When the bookmark is a non-emptry string, the iterator can be used to fetch
the first `pageSize` keys between the bookmark (inclusive) and endKey (exclusive).
Note that only the bookmark present in a prior page of query results (ResponseMetadata)
can be used as a value to the bookmark argument. Otherwise, an empty string must
be passed as bookmark.
The keys are returned by the iterator in lexical order. Note
that startKey and endKey can be empty string, which implies unbounded range
query on start or end.
Call Close() on the returned StateQueryIteratorInterface object when done.
This call is only supported in a read only transaction.
Parameters:
| Name |
Type |
Description |
startKey |
string
|
|
endKey |
string
|
|
pageSize |
int
|
|
bookmark |
string
|
|
Returns:
Promise for a PaginationQueryResponse object
-
Type
-
Promise
-
<async> getStateValidationParameter(key)
-
getStateValidationParameter retrieves the key-level endorsement policy
for `key`. Note that this will introduce a read dependency on `key` in
the transaction's readset.
Parameters:
| Name |
Type |
Description |
key |
string
|
State variable key to set endorsement policy |
Returns:
returns the endorsement policy for this key
-
Type
-
Buffer
-
getStringArgs()
-
Returns the arguments as array of strings from the chaincode invocation request
Returns:
-
Type
-
Array.<string>
-
getTransient()
-
Returns the transient map that can be used by the chaincode but not
saved in the ledger, such as cryptographic information for encryption and decryption
Returns:
-
Type
-
Map.<string:Buffer>
-
getTxID()
-
Returns the transaction ID for the current chaincode invocation request. The transaction
ID uniquely identifies the transaction within the scope of the channel.
-
getTxTimestamp()
-
Returns the timestamp when the transaction was created. This
is taken from the transaction ChannelHeader, therefore it will indicate the
client's timestamp, and will have the same value across all endorsers.
Object returned: { seconds: [Long] { low: [int32], high: [int32], unsigned: [bool] }, nanos: [int32] }
-
<async> invokeChaincode(chaincodeName, args, channel)
-
Locally calls the specified chaincode invoke() using the
same transaction context; that is, chaincode calling chaincode doesn't
create a new transaction message.
If the called chaincode is on the same channel, it simply adds the called
chaincode read set and write set to the calling transaction.
If the called chaincode is on a different channel,
only the Response is returned to the calling chaincode; any PutState calls
from the called chaincode will not have any effect on the ledger; that is,
the called chaincode on a different channel will not have its read set
and write set applied to the transaction. Only the calling chaincode's
read set and write set will be applied to the transaction. Effectively
the called chaincode on a different channel is a `Query`, which does not
participate in state validation checks in subsequent commit phase.
If `channel` is empty, the caller's channel is assumed.
Parameters:
| Name |
Type |
Description |
chaincodeName |
string
|
Name of the chaincode to call |
args |
Array.<Array.<byte>>
|
List of arguments to pass to the called chaincode |
channel |
string
|
Name of the channel where the target chaincode is active |
Returns:
Promise for a Response object returned by the called chaincode
-
Type
-
Promise
-
<async> putPrivateData(collection, key, value)
-
putPrivateData puts the specified `key` and `value` into the transaction's
private writeSet. Note that only hash of the private writeSet goes into the
transaction proposal response (which is sent to the client who issued the
transaction) and the actual private writeSet gets temporarily stored in a
transient store. PutPrivateData doesn't effect the `collection` until the
transaction is validated and successfully committed. Simple keys must not be
an empty string and must not start with null character (0x00), in order to
avoid range query collisions with composite keys, which internally get
prefixed with 0x00 as composite key namespace.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name |
key |
string
|
Private data variable key to set the value for |
value |
string
|
Array.<byte>
|
Private data variable value |
-
<async> putState(key, value)
-
Writes the state variable key of value value
to the state store. If the variable already exists, the value will be
overwritten.
Parameters:
| Name |
Type |
Description |
key |
string
|
State variable key to set the value for |
value |
Array.<byte>
|
string
|
State variable value |
Returns:
Promise will be resolved when the peer has successfully handled the state update request
or rejected if any errors
-
Type
-
Promise
-
setEvent(name, payload)
-
Allows the chaincode to propose an event on the transaction proposal. When the transaction
is included in a block and the block is successfully committed to the ledger, the block event
will be delivered to the current event listeners that have been registered with the peer's
event producer. Note that the block event gets delivered to the listeners regardless of the
status of the included transactions (can be either valid or invalid), so client applications
are responsible for checking the validity code on each transaction. Consult each SDK's documentation
for details.
Parameters:
| Name |
Type |
Description |
name |
string
|
Name of the event |
payload |
Array.<byte>
|
A payload can be used to include data about the event |
-
<async> setPrivateDataValidationParameter(collection, key, ep)
-
SetPrivateDataValidationParameter sets the key-level endorsement policy
for the private data specified by `key`.
Parameters:
| Name |
Type |
Description |
collection |
string
|
The collection name for this private data |
key |
string
|
Private data variable key to set endorsement policy |
ep |
Buffer
|
endorsement policy |
-
<async> setStateValidationParameter(key, ep)
-
Sets the key-level endorsement policy for `key`
Parameters:
| Name |
Type |
Description |
key |
string
|
State variable key to set endorsement policy |
ep |
Buffer
|
endorsement policy |
-
splitCompositeKey(compositeKey)
-
Splits the specified key into attributes on which the composite key was formed.
Composite keys found during range queries or partial composite key queries can
therefore be split into their original composite parts, essentially recovering
the values of the attributes.
Parameters:
| Name |
Type |
Description |
compositeKey |
string
|
The composite key to split |
Returns:
An object which has properties of 'objectType' (string) and
'attributes' (string[])
-
Type
-
Object