Question

我有一个nodejs C ++模块，我想了解如何报告初始化错误。所以这个样板是：

vagrant@precise64:~/elasticsearch/bin$ ./elasticsearch
[2016-04-03 10:55:01,423][INFO ][node                     ] [Araña] version[2.3.0], pid[6748], build[8371be8/2016-03-29T07:54:48Z]
[2016-04-03 10:55:01,424][INFO ][node                     ] [Araña] initializing ...
[2016-04-03 10:55:02,296][INFO ][plugins                  ] [Araña] modules [reindex, lang-expression, lang-groovy], plugins [], sites []
[2016-04-03 10:55:02,328][INFO ][env                      ] [Araña] using [1] data paths, mounts [[/ (/dev/sda1)]], net usable_space [35.1gb], net total_space [39.4gb], spins? [possibly], types [ext4]
[2016-04-03 10:55:02,328][INFO ][env                      ] [Araña] heap size [1015.6mb], compressed ordinary object pointers [true]
[2016-04-03 10:55:02,329][WARN ][env                      ] [Araña] max file descriptors [4096] for elasticsearch process likely too low, consider increasing to at least [65536]
[2016-04-03 10:55:05,107][INFO ][node                     ] [Araña] initialized
[2016-04-03 10:55:05,108][INFO ][node                     ] [Araña] starting ...
[2016-04-03 10:55:05,228][INFO ][transport                ] [Araña] publish_address {127.0.0.1:9300}, bound_addresses {[::1]:9300}, {127.0.0.1:9300}
[2016-04-03 10:55:05,238][INFO ][discovery                ] [Araña] elasticsearch/gf23pBqpSs2wDrLswVeSyQ
[2016-04-03 10:55:08,313][INFO ][cluster.service          ] [Araña] new_master {Araña}{gf23pBqpSs2wDrLswVeSyQ}{127.0.0.1}{127.0.0.1:9300}, reason: zen-disco-join(elected_as_master, [0] joins received)
[2016-04-03 10:55:08,341][INFO ][http                     ] [Araña] publish_address {127.0.0.1:9200}, bound_addresses {[::1]:9200}, {127.0.0.1:9200}
[2016-04-03 10:55:08,342][INFO ][node                     ] [Araña] started
[2016-04-03 10:55:08,366][INFO ][gateway                  ] [Araña] recovered [0] indices into cluster_state
^C[2016-04-03 10:55:22,870][INFO ][node                     ] [Araña] stopping ...
[2016-04-03 10:55:22,884][INFO ][node                     ] [Araña] stopped
[2016-04-03 10:55:22,885][INFO ][node                     ] [Araña] closing ...
[2016-04-03 10:55:22,899][INFO ][node                     ] [Araña] closed

如果extern "C" void Initialize(v8::Handle<v8::Object> instance) { // Do initialization stuff } NODE_MODULE(SomeModuleType, Initialize)没有返回类型，我怎么能在Initialize内报告错误，因为它是extern "C"而不允许我抛出？我应该调用一些具体的回调吗？

此外，从暴露给nodejs的回调方法报告错误的最佳做法是什么？返回null对象是常见的做法，还是可以扔到那里，这会在javascript端显示为异常？

Answer 1

在潜伏在nodejs源码之后，我发现了这一点，但是仍然欢迎评论，关于这是否是一个好方法：

extern "C" void Initialize(v8::Handle<v8::Object> instance)
{
    try
    {
        // Do something unsafe
    }
    catch (std::exception& Exception)
    {
        node::Environment::GetCurrent(v8::Isolate::GetCurrent())->ThrowError("module initialization failed");
    }
}

如果我只是重新抛出异常，那么在调试器下执行就不是我想要的了。

从nodejs模块初始化函数报告失败

1 个答案: