LongStack

LongStack 会在异常产生时自动附加前序调用堆栈，并支持过滤用户代码（模块）所产生的堆栈，帮助快速定位异步调用问题。

使用此模块时，Node.js 版本需大于 v8.2.x

安装

npm i longstack

用法

const longstack = require('longstack');
longstack.enable([options]);

options:

• removeNativeCode: 是否移除非用户代码产生的堆栈， 默认值为 false
• maxAsyncDepth: 最大异步调用栈深度， 默认值为 64

配置全局生效，只需在用户代码入口处开启即可。

请注意：此模块启动后会造成性能损耗，性能敏感代码请勿使用此模块。

例子

Promise.resolve(1).then(val => {
    setTimeout(()=>{
        try {
            ThisMayThrowError;
        } catch(err) {
            console.error(err);
        };
    }, 1000);
});

上面的代码执行后会打印出如下错误：

ReferenceError: ThisMayThrowError is not defined
at Timeout.setTimeout as _onTimeout
at ontimeout (timers.js:427:11)
at tryOnTimeout (timers.js:289:5)
at listOnTimeout (timers.js:252:5)
at Timer.processTimers (timers.js:212:10)

Timeout.setTimeout 之前的执行堆栈都丢失了。 在开启 LongStack 后，会打印出从 loader 到当前模块的（异步）执行堆栈（如下所示）：

ReferenceError: ThisMayThrowError is not defined
at Timeout.setTimeout as _onTimeout
at ontimeout (timers.js:427:11)
at tryOnTimeout (timers.js:289:5)
at listOnTimeout (timers.js:252:5)
at Timer.processTimers (timers.js:212:10)
at emitInitNative (internal/async_hooks.js:137:43)
at emitInitScript (internal/async_hooks.js:336:3)
at initAsyncResource (internal/timers.js:50:5)
at new Timeout (internal/timers.js:82:3)
at setTimeout (timers.js:403:19)
at Promise.resolve.then.val (test.js:6:5)
at process._tickCallback (internal/process/next_tick.js:178:7)
at Function.Module.runMain (internal/modules/cjs/loader.js:721:11)
at startup (internal/bootstrap/node.js:228:19)
at PromiseWrap.emitInitNative (internal/async_hooks.js:137:43)
at Promise.then ()
at Object. (test.js:5:20)
at Module._compile (internal/modules/cjs/loader.js:678:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:689:10)
at Module.load (internal/modules/cjs/loader.js:589:32)
at tryModuleLoad (internal/modules/cjs/loader.js:528:12)
at Function.Module._load (internal/modules/cjs/loader.js:520:3)
at Function.Module.runMain (internal/modules/cjs/loader.js:719:10)

如果想过滤出用户（模块）代码，可以开启 removeNativeCode 选项，以便于查看与定位问题：

ReferenceError: ThisMayThrowError is not defined
at Timeout.setTimeout as _onTimeout
at Promise.resolve.then.val (test.js:8:5)
at Object. (test.js:7:20)