2025-09-05 14:59:21 +08:00

132 lines
3.7 KiB
JavaScript

function createContext(opts = {}) {
let currentInstance;
let isSingleton = false;
const checkConflict = (instance) => {
if (currentInstance && currentInstance !== instance) {
throw new Error("Context conflict");
}
};
let als;
if (opts.asyncContext) {
const _AsyncLocalStorage = opts.AsyncLocalStorage || globalThis.AsyncLocalStorage;
if (_AsyncLocalStorage) {
als = new _AsyncLocalStorage();
} else {
console.warn("[unctx] `AsyncLocalStorage` is not provided.");
}
}
const _getCurrentInstance = () => {
if (als) {
const instance = als.getStore();
if (instance !== void 0) {
return instance;
}
}
return currentInstance;
};
return {
use: () => {
const _instance = _getCurrentInstance();
if (_instance === void 0) {
throw new Error("Context is not available");
}
return _instance;
},
tryUse: () => {
return _getCurrentInstance();
},
set: (instance, replace) => {
if (!replace) {
checkConflict(instance);
}
currentInstance = instance;
isSingleton = true;
},
unset: () => {
currentInstance = void 0;
isSingleton = false;
},
call: (instance, callback) => {
checkConflict(instance);
currentInstance = instance;
try {
return als ? als.run(instance, callback) : callback();
} finally {
if (!isSingleton) {
currentInstance = void 0;
}
}
},
async callAsync(instance, callback) {
currentInstance = instance;
const onRestore = () => {
currentInstance = instance;
};
const onLeave = () => currentInstance === instance ? onRestore : void 0;
asyncHandlers.add(onLeave);
try {
const r = als ? als.run(instance, callback) : callback();
if (!isSingleton) {
currentInstance = void 0;
}
return await r;
} finally {
asyncHandlers.delete(onLeave);
}
}
};
}
function createNamespace(defaultOpts = {}) {
const contexts = {};
return {
get(key, opts = {}) {
if (!contexts[key]) {
contexts[key] = createContext({ ...defaultOpts, ...opts });
}
return contexts[key];
}
};
}
const _globalThis = typeof globalThis !== "undefined" ? globalThis : typeof self !== "undefined" ? self : typeof global !== "undefined" ? global : typeof window !== "undefined" ? window : {};
const globalKey = "__unctx__";
const defaultNamespace = _globalThis[globalKey] || (_globalThis[globalKey] = createNamespace());
const getContext = (key, opts = {}) => defaultNamespace.get(key, opts);
const useContext = (key, opts = {}) => getContext(key, opts).use;
const asyncHandlersKey = "__unctx_async_handlers__";
const asyncHandlers = _globalThis[asyncHandlersKey] || (_globalThis[asyncHandlersKey] = /* @__PURE__ */ new Set());
function executeAsync(function_) {
const restores = [];
for (const leaveHandler of asyncHandlers) {
const restore2 = leaveHandler();
if (restore2) {
restores.push(restore2);
}
}
const restore = () => {
for (const restore2 of restores) {
restore2();
}
};
let awaitable = function_();
if (awaitable && typeof awaitable === "object" && "catch" in awaitable) {
awaitable = awaitable.catch((error) => {
restore();
throw error;
});
}
return [awaitable, restore];
}
function withAsyncContext(function_, transformed) {
if (!transformed) {
console.warn(
"[unctx] `withAsyncContext` needs transformation for async context support in",
function_,
"\n",
function_.toString()
);
}
return function_;
}
export { createContext, createNamespace, defaultNamespace, executeAsync, getContext, useContext, withAsyncContext };