Module holochain::core

Defines the core Holochain workflows

Modules

• encode
  Include nice string encoding methods and From impls
• fixt
• hash_type
  Defines the prefixes for the various HashTypes, as well as the traits which unify them
• queue_consumer
  Manages the spawning of tasks which process the various work queues in the system, as well as notifying subsequent queue processors to pick up the work that was left off.
• ribosome
  A Ribosome is a structure which knows how to execute hApp code.
• workflow
  Workflows are the core building block of Holochain functionality.

Macros

• assert_length
  Helper for ensuring the the proper number of bytes is used in various situations
• impl_hashable_content
  A default HashableContent implementation, suitable for content which is already TryInto<SerializedBytes>, and uses a PrimitiveHashType

Structs

• CompositeHashConversionError
  Error converting a composite hash into a subset composite hash, due to type mismatch
• EntryHashes
  A newtype for a collection of EntryHashes, needed for some wasm return types.
• HashConversionError
  Error converting a composite hash into a primitive one, due to type mismatch
• HoloHash
  A HoloHash contains a vector of 36 bytes representing a 32-byte blake2b hash plus 4 bytes representing a DHT location. It also contains a zero-sized type which specifies what it is a hash of.
• HoloHashB64
  A wrapper around HoloHash that Serializes into a base64 string rather than a raw byte array.
• HoloHashed
  Represents some piece of content along with its hash representation, so that hashes need not be calculated multiple times. Provides an easy constructor which consumes the content.
• IncomingDhtOpSender
  Allows you to send an op to the incoming_dht_ops_workflow if you found it on the network and were supposed to be holding it.
• PrevActionError
  Context information for an invalid action to make it easier to trace in errors.
• Timestamp
  A microsecond-precision UTC timestamp for use in Holochain’s actions.

Enums

• AnyDhtHashPrimitive
  The primitive hash types represented by this composite hash
• AnyLinkableHashPrimitive
  The primitive hash types represented by this composite hash
• HashableContentBytes
  HashableContent can be expressed as “content”, or “prehashed”, which affects how a HoloHashed type will be constructed from it.
• PrevActionErrorKind
• SourceChainError
• SysValidationError
  Validation can result in either
• ValidationOutcome
  All the outcomes that can come from validation This is not an error type it is the outcome of failed validation.

Constants

• HOLO_HASH_CORE_LEN
  Length of the core bytes (32)
• HOLO_HASH_FULL_LEN
  Length of the full HoloHash bytes (39 = 3 + 32 + 4)
• HOLO_HASH_LOC_LEN
  Length of the location bytes (4)
• HOLO_HASH_PREFIX_LEN
  Length of the prefix bytes (3)
• HOLO_HASH_UNTYPED_LEN
  Length of the core bytes + the loc bytes (36 = 32 + 4), i.e. everything except the type prefix
• MAX_ENTRY_SIZE
  16mb limit on Entries due to websocket limits. 4mb limit to constrain bandwidth usage on uploading. (Assuming a baseline 5mbps upload for now… update this as consumer internet connections trend toward more upload) Consider splitting large entries up.
• MAX_HASHABLE_CONTENT_LEN
  The maximum size to hash synchronously. Anything larger than this will take too long to hash within a single tokio context
• MAX_TAG_SIZE
  1kb limit on LinkTags. Tags are used as keys to the database to allow fast lookup so they should be small.

Traits

• HasHash
  Anything which has an owned HoloHashOf.
• HashType
  Every HoloHash is generic over HashType. Additionally, every HashableContent has an associated HashType. The HashType is the glue that binds together HashableContent with its hash.
• HashableContent
  Any implementor of HashableContent may be used in a HoloHashed to pair data with its HoloHash representation. It also has an associated HashType.
• HashableContentExtAsync
  Adds convenience methods for constructing HoloHash and HoloHashed from some HashableContent
• HashableContentExtSync
  Adds convenience methods for constructing HoloHash and HoloHashed from some HashableContent
• PrimitiveHashType
  A PrimitiveHashType is one with a multihash prefix. In contrast, a non-primitive hash type could be one of several primitive types, e.g. an AnyDhtHash can represent one of three primitive types.

Functions

• author_key_is_valid
  Verify the author key was valid at the time of signing with dpki TODO: This is just a stub until we have dpki.
• blake2b_256
  internal compute a 32 byte blake2b hash
• bytes_to_hex
  Get a hex string representation of two chars per byte
• check_agent_validation_pkg_predecessor
  Check that created agents are always paired with an AgentValidationPkg and vice versa
• check_and_hold_any_store_entry
  If we are not holding this entry then retrieve any record at this EntryHash and send it as a StoreEntry DhtOp to our incoming_dht_ops_workflow.
• check_and_hold_register_add_link
  If we are not holding this action then retrieve it and send it as a RegisterAddLink DhtOp to our incoming_dht_ops_workflow.
• check_and_hold_register_agent_activity
  If we are not holding this action then retrieve it and send it as a RegisterAgentActivity DhtOp to our incoming_dht_ops_workflow.
• check_and_hold_store_entry
  If we are not holding this action then retrieve it and send it as a StoreEntry DhtOp to our incoming_dht_ops_workflow.
• check_and_hold_store_record
  If we are not holding this action then retrieve it and send it as a StoreRecord DhtOp to our incoming_dht_ops_workflow.
• check_chain_rollback
  Check if there are other actions at this sequence number
• check_countersigning_preflight_response_signature
  Verify that the signature on a preflight request is valid.
• check_countersigning_session_data
  Verify all the countersigning session data together.
• check_countersigning_session_data_contains_action
  Verify the countersigning session contains the specified action.
• check_entry_hash
  Check the actions entry hash matches the hash of the entry
• check_entry_size
  Check the entry size is under the MAX_ENTRY_SIZE
• check_entry_type
  Check the entry variant matches the variant in the actions entry type
• check_entry_visibility
  Check that the EntryVisibility is congruous with the presence or absence of entry data
• check_new_entry_action
  Check the action should have an entry. Is either a Create or Update
• check_prev_action
  Check that the correct actions have the correct setting for prev_action:
• check_prev_author
  Check that the author didn’t change between actions
• check_prev_seq
  Check the previous action is one less than the current
• check_prev_timestamp
  Check previous action timestamp is before this action
• check_spam
  Placeholder for future spam check. Check action timestamps don’t exceed MAX_PUBLISH_FREQUENCY
• check_tag_size
  Check the link tag size is under the MAX_TAG_SIZE
• check_update_reference
  Check a Update’s entry type is the same for original and new entry.
• check_valid_if_dna
  Check that Dna actions are only added to empty source chains
• holo_hash_decode
  internal PARSE for holo hash REPR
• holo_hash_decode_unchecked
  internal PARSE for holo hash REPR
• holo_hash_encode
  internal REPR for holo hash
• validate_chain
  Validate a chain of actions with an optional starting point.
• verify_action_signature
  Verify the signature for this action

Type Aliases

• ActionHash
  The hash of an action
• ActionHashB64
  Base64-ready version of ActionHash
• ActionHashed
• AgentPubKey
  An Agent public signing key. Not really a hash, more of an “identity hash”.
• AgentPubKeyB64
  Base64-ready version of AgentPubKey
• AnyDhtHash
  The hash of anything referrable in the DHT. This is a composite of either an EntryHash or a ActionHash
• AnyDhtHashB64
  Base64-ready version of AnyDhtHash
• AnyLinkableHash
  The hash of anything linkable.
• AnyLinkableHashB64
  Base64-ready version of AnyLinkableHash
• DhtOpHash
  The hash of a DhtOp’s “unique form” representation
• DhtOpHashB64
  Base64-ready version of DhtOpHash
• DnaHash
  The hash of a DnaDef
• DnaHashB64
  Base64-ready version of DnaHash
• EntryHash
  The hash of an Entry.
• EntryHashB64
  Base64-ready version of EntryHash
• ExternalHash
  The hash of some external data that can’t or doesn’t exist on the DHT.
• ExternalHashB64
  Base64-ready version of ExternalHash
• HoloHashOf
  A convenience type, for specifying a hash by HashableContent rather than by its HashType
• NetIdHash
  The hash of a network ID
• NetIdHashB64
  Base64-ready version of NetIdHash
• OpBasis
  Alias for AnyLinkableHash. This hash forms the notion of the “basis hash” of an op.
• SourceChainResult
• SysValidationOutcome
  Return either:
• SysValidationResult
• WasmHash
  The hash of some wasm bytecode
• WasmHashB64
  Base64-ready version of WasmHash
• ZomeCallSigningKey
  A public key of a pair of signing keys for signing zome calls.