mirror of
https://github.com/fluencelabs/marine.git
synced 2024-12-12 14:55:32 +00:00
140 lines
4.0 KiB
Markdown
140 lines
4.0 KiB
Markdown
# Fluence Compute Engine
|
|
|
|
FCE is a general purpose Wasm runtime that could be used in different scenarios, especially in programs based on the [ECS](https://en.wikipedia.org/wiki/Entity_component_system) pattern or plugin architecture. It runs multi-module WebAssembly applications with interface-types and shared-nothing linking scheme.
|
|
|
|
Fluence [nodes](https://github.com/fluencelabs/fluence) use FCE to execute [aquamarine](https://github.com/fluencelabs/aquamarine) and services compiled to Wasm:
|
|
|
|
<p width="100%">
|
|
<img alt="fluence stack" align="center" src="images/fluence_stack_overview.png"/>
|
|
</p>
|
|
|
|
At now, it is in the heavily developing phase, docs and tutorials are also in the work-in-progress state.
|
|
|
|
## Installation
|
|
- `cargo install fcli`
|
|
|
|
this will add `fce` binary to your system.
|
|
|
|
## Usage
|
|
- `fce build` in Rust project
|
|
|
|
## HOW TO: Create an App with FCE Modules
|
|
|
|
### Recommendations:
|
|
|
|
- Modules architecture should be upwards from `effectors` (modules that persist data and WASI modules) that will work with local binaries, local storage and syscalls to `pure modules` that perform business logic.
|
|
- Split app to small FCE modules are easier to support, reuse and distribute
|
|
- Each module for its own task (npm like)
|
|
|
|
### Module project structure
|
|
|
|
- Init simple rust project `cargo init --bin`
|
|
|
|
- `Config.toml`:
|
|
```toml
|
|
[[bin]]
|
|
name = "wasm_application"
|
|
path = "src/main.rs"
|
|
|
|
[dependencies]
|
|
# logger - if you'll use logging
|
|
fluence = { git = "https://github.com/fluencelabs/rust-sdk", features = ["logger"] }
|
|
```
|
|
|
|
- Methods that will be exported from this module marked with `#[fce]`
|
|
```rust
|
|
use fluence::fce;
|
|
|
|
#[fce]
|
|
pub fn get(url: String) -> String {
|
|
...
|
|
}
|
|
```
|
|
- Multiple arguments with primitive Rust types (`bool, u8, u16, u32, u64, i8, i16, i32, i64, f32, f64, String, Vec<u8>`) and only one return argument could be used
|
|
|
|
- Build project with `fce build` (supports --release and all other cargo flags as usual)
|
|
|
|
- Copy wasm file from `target/wasm32-wasi/debug` or `target/wasm32-wasi/release` to directory with other modules
|
|
|
|
- To import other wasm modules to your project use similar code:
|
|
```rust
|
|
#[fce]
|
|
#[link(wasm_import_module = "curl")]
|
|
extern "C" {
|
|
#[link_name = "get"]
|
|
pub fn curl_get(url: String) -> String;
|
|
}
|
|
|
|
#[fce]
|
|
#[link(wasm_import_module = "local_storage")]
|
|
extern "C" {
|
|
#[link_name = "get"]
|
|
pub fn curl_get(url: String) -> String;
|
|
}
|
|
```
|
|
|
|
### Combine modules to Application
|
|
|
|
- Create simple Rust project
|
|
- Create `Config.toml` to describe existed wasm modules and give accesses to host binaries and local storage if needed:
|
|
```toml
|
|
modules_dir = "wasm/artifacts/modules/"
|
|
|
|
[[module]]
|
|
name = "local_storage"
|
|
logger_enabled = true
|
|
|
|
[module.wasi]
|
|
preopened_files = ["./wasm/artifacts"]
|
|
mapped_dirs = { "sites" = "./sites" }
|
|
|
|
[[module]]
|
|
name = "curl"
|
|
logger_enabled = true
|
|
|
|
[module.mounted_binaries]
|
|
curl = "/usr/bin/curl"
|
|
|
|
[[module]]
|
|
name = "site-storage"
|
|
mem_pages_count = 10000
|
|
logger_enabled = true
|
|
|
|
[module.wasi]
|
|
envs = { "ENV_ONE" = "parameter-one" }
|
|
```
|
|
|
|
`modules_dir` - path to directory with all modules. All subsequent paths will be relative to this path
|
|
|
|
`[[module]]` - modules list
|
|
|
|
`name` - wasm file name in `modules_dir`
|
|
|
|
`mem_pages_count` - a maximum number of Wasm memory pages that loaded module can use. Each Wasm pages is 65536 bytes long
|
|
|
|
`[module.mounted_binaries]` - list of mounted binary executable files
|
|
|
|
`curl = "/usr/bin/curl"` - gives possibility to call binary file `/usr/bin/curl` as method `curl` in Rust code
|
|
|
|
Import example:
|
|
```rust
|
|
#[fce]
|
|
#[link(wasm_import_module = "host")]
|
|
extern "C" {
|
|
fn curl(args: String) -> String;
|
|
}
|
|
```
|
|
|
|
Call binary with arguments: `curl("-vvv ya.ru")`
|
|
|
|
`[module.wasi]` - this block manages communication with the "outside" world
|
|
`env` - environment variables. Usage: `std::env::var("IPFS_ADDR")`
|
|
`preopened_files` - list of available directories for loaded modules
|
|
`mapped_dirs` - mapping between paths
|
|
|
|
Working with files as usual:
|
|
```rust
|
|
fs::write(PathBuf::from("/tmp/somefile"), vec!(1,2,3));
|
|
fs::read(...);
|
|
```
|