pub struct CommandPre<T> { /* private fields */ }
Expand description
Pre-instantiated analog of Command
This can be used to front-load work such as export lookup before instantiation.
§Examples
use wasmtime::{Engine, Result, Store, Config};
use wasmtime::component::{ResourceTable, Linker, Component};
use wasmtime_wasi::{WasiCtx, WasiView, WasiCtxBuilder};
use wasmtime_wasi::bindings::CommandPre;
// This example is an example shim of executing a component based on the
// command line arguments provided to this program.
#[tokio::main]
async fn main() -> Result<()> {
let args = std::env::args().skip(1).collect::<Vec<_>>();
// Configure and create `Engine`
let mut config = Config::new();
config.async_support(true);
let engine = Engine::new(&config)?;
// Configure a `Linker` with WASI, compile a component based on
// command line arguments, and then pre-instantiate it.
let mut linker = Linker::<MyState>::new(&engine);
wasmtime_wasi::add_to_linker_async(&mut linker)?;
let component = Component::from_file(&engine, &args[0])?;
let pre = CommandPre::new(linker.instantiate_pre(&component)?)?;
// Configure a `WasiCtx` based on this program's environment. Then
// build a `Store` to instantiate into.
let mut builder = WasiCtxBuilder::new();
builder.inherit_stdio().inherit_env().args(&args);
let mut store = Store::new(
&engine,
MyState {
ctx: builder.build(),
table: ResourceTable::new(),
},
);
// Instantiate the component and we're off to the races.
let command = pre.instantiate_async(&mut store).await?;
let program_result = command.wasi_cli_run().call_run(&mut store).await?;
match program_result {
Ok(()) => Ok(()),
Err(()) => std::process::exit(1),
}
}
struct MyState {
ctx: WasiCtx,
table: ResourceTable,
}
impl WasiView for MyState {
fn ctx(&mut self) -> &mut WasiCtx { &mut self.ctx }
fn table(&mut self) -> &mut ResourceTable { &mut self.table }
}
Auto-generated bindings for a pre-instantiated version of a
component which implements the world command
.
This structure is created through CommandPre::new
which
takes a InstancePre
that
has been created through a Linker
.
For more information see Command
as well.
Implementations§
Source§impl<_T> CommandPre<_T>
impl<_T> CommandPre<_T>
Sourcepub fn new(instance_pre: InstancePre<_T>) -> Result<Self>
pub fn new(instance_pre: InstancePre<_T>) -> Result<Self>
Creates a new copy of CommandPre
bindings which can then
be used to instantiate into a particular store.
This method may fail if the component behind instance_pre
does not have the required exports.
pub fn engine(&self) -> &Engine
pub fn instance_pre(&self) -> &InstancePre<_T>
Sourcepub async fn instantiate_async(
&self,
store: impl AsContextMut<Data = _T>,
) -> Result<Command>where
_T: Send,
pub async fn instantiate_async(
&self,
store: impl AsContextMut<Data = _T>,
) -> Result<Command>where
_T: Send,
Instantiates a new instance of Command
within the
store
provided.
This function will use self
as the pre-instantiated
instance to perform instantiation. Afterwards the preloaded
indices in self
are used to lookup all exports on the
resulting instance.
Trait Implementations§
Auto Trait Implementations§
impl<T> Freeze for CommandPre<T>
impl<T> !RefUnwindSafe for CommandPre<T>
impl<T> Send for CommandPre<T>
impl<T> Sync for CommandPre<T>
impl<T> Unpin for CommandPre<T>
impl<T> !UnwindSafe for CommandPre<T>
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
Source§impl<T> GetSetFdFlags for T
impl<T> GetSetFdFlags for T
Source§fn get_fd_flags(&self) -> Result<FdFlags, Error>where
T: AsFilelike,
fn get_fd_flags(&self) -> Result<FdFlags, Error>where
T: AsFilelike,
self
file descriptor.Source§fn new_set_fd_flags(&self, fd_flags: FdFlags) -> Result<SetFdFlags<T>, Error>where
T: AsFilelike,
fn new_set_fd_flags(&self, fd_flags: FdFlags) -> Result<SetFdFlags<T>, Error>where
T: AsFilelike,
Source§fn set_fd_flags(&mut self, set_fd_flags: SetFdFlags<T>) -> Result<(), Error>where
T: AsFilelike,
fn set_fd_flags(&mut self, set_fd_flags: SetFdFlags<T>) -> Result<(), Error>where
T: AsFilelike,
self
file descriptor. Read more