Crate anchor_lang

Anchor ⚓ is a framework for Solana’s Sealevel runtime providing several convenient developer tools.

• Rust eDSL for writing safe, secure, and high level Solana programs
• IDL specification
• TypeScript package for generating clients from IDL
• CLI and workspace management for developing complete applications

If you’re familiar with developing in Ethereum’s Solidity, Truffle, web3.js or Parity’s Ink!, then the experience will be familiar. Although the syntax and semantics are targeted at Solana, the high level workflow of writing RPC request handlers, emitting an IDL, and generating clients from IDL is the same.

For detailed tutorials and examples on how to use Anchor, see the guided tutorials or examples in the GitHub repository.

Presented here are the Rust primitives for building on Solana.

Re-exports

pub use solana_program;

Modules

accounts

Account types that can be used in the account validation struct.

context

Data structures that are used to provide non-argument inputs to program endpoints

error

prelude

The prelude contains all commonly used components of the crate. All programs should include it via anchor_lang::prelude::*;.

system_program

Macros

declare_id

Defines the program’s ID. This should be used at the root of all Anchor based programs.

declare_program

Declare an external program based on its IDL.

emit

Logs an event that can be subscribed to by clients. Uses the sol_log_data syscall which results in the following log:

emit_cpievent-cpi

Log an event by making a self-CPI that can be subscribed to by clients.

err

Returns with the given error. Use this with a custom error type.

error

Generates an Error::AnchorError that includes file and line information.

pubkey

Convenience macro to define a static public key.

require

Ensures a condition is true, otherwise returns with the given error. Use this with or without a custom error type.

require_eq

Ensures two NON-PUBKEY values are equal.

require_gt

Ensures the first NON-PUBKEY value is greater than the second NON-PUBKEY value.

require_gte

Ensures the first NON-PUBKEY value is greater than or equal to the second NON-PUBKEY value.

require_keys_eq

Ensures two pubkeys values are equal.

require_keys_neq

Ensures two pubkeys are not equal.

require_neq

Ensures two NON-PUBKEY values are not equal.

source

Creates a Source

Structs

ProgramData

Traits

AccountDeserialize

A data structure that can be deserialized and stored into account storage, i.e. an AccountInfo’s mutable data slice.

AccountSerialize

A data structure that can be serialized and stored into account storage, i.e. an AccountInfo’s mutable data slice.

Accounts

A data structure of validated accounts that can be deserialized from the input to a Solana program. Implementations of this trait should perform any and all requisite constraint checks on accounts to ensure the accounts maintain any invariants required for the program to run securely. In most cases, it’s recommended to use the Accounts derive macro to implement this trait.

AccountsClose

The close procedure to initiate garabage collection of an account, allowing one to retrieve the rent exemption.

AccountsExit

The exit procedure for an account. Any cleanup or persistence to storage should be done here.

AnchorDeserialize

Borsh is the default serialization format for instructions and accounts. A data-structure that can be de-serialized from binary format by NBOR.

AnchorSerialize

A data-structure that can be serialized into binary format by NBOR.

Bump

Bump seed for program derived addresses.

Bumps

Associated bump seeds for Accounts.

CheckId

Defines a trait for checking the id of a program.

CheckOwner

Defines a trait for checking the owner of a program.

Discriminator

Unique identifier for a type.

Event

An event that can be emitted via a Solana log. See emit! for an example.

Id

Defines the id of a program.

IdlBuildidl-build

A trait that types must implement in order to include the type in the IDL definition.

Ids

Defines the possible ids of a program.

InstructionData

Calculates the data for an instruction invocation, where the data is Discriminator + BorshSerialize(args). args is a borsh serialized struct of named fields for each argument given to an instruction.

Key

Defines the Pubkey of an account.

Lamports

Lamports related utility methods for accounts.

Owner

Defines an address expected to own an account.

Owners

Defines a list of addresses expected to own an account.

Space

Defines the space of an account for initialization.

ToAccountInfo

Transformation to an AccountInfo struct.

ToAccountInfos

Transformation to AccountInfo structs.

ToAccountMetas

Transformation to AccountMeta structs.

ZeroCopy

An account data structure capable of zero copy deserialization.

Type Aliases

Result

Attribute Macros

access_control

Executes the given access control method before running the decorated instruction handler. Any method in scope of the attribute can be invoked with any arguments from the associated instruction handler.

account

An attribute for a data structure representing a Solana account.

constant

A marker attribute used to mark const values that should be included in the generated IDL but functionally does nothing.

error_code

Generates Error and type Result<T> = Result<T, Error> types to be used as return types from Anchor instruction handlers. Importantly, the attribute implements From on the ErrorCode to support converting from the user defined error enum into the generated Error.

event

The event attribute allows a struct to be used with emit! so that programs can log significant events in their programs that clients can subscribe to. Currently, this macro is for structs only.

event_cpievent-cpi

An attribute macro to add necessary event CPI accounts to the given accounts struct.

instruction

This attribute is used to override the Anchor defaults of program instructions.

interfaceinterface-instructions

The #[interface] attribute is used to mark an instruction as belonging to an interface implementation, thus transforming its discriminator to the proper bytes for that interface instruction.

program

The #[program] attribute defines the module containing all instruction handlers defining all entries into a Solana program.

zero_copy

A data structure that can be used as an internal field for a zero copy deserialized account, i.e., a struct marked with #[account(zero_copy)].

Derive Macros

Accounts

Implements an Accounts deserializer on the given struct. Can provide further functionality through the use of attributes.

AnchorDeserialize

AnchorSerialize

InitSpace

Implements a Space trait on the given struct or enum.