Question

我正在使用Apache + mod_lua对一个简单的“输出”过滤器进行原型设计。如何通过LUA在应用的其他本机输出过滤器的末尾读取响应体？例如，我可以获得将发送给客户的实际响应吗？

Answer 1

本手册对此有一些很好的指导：

http://httpd.apache.org/docs/current/mod/mod_lua.html#modifying_buckets

使用Lua过滤器修改内容过滤器通过实现的功能 LuaInputFilter或LuaOutputFilter设计为三阶段使用协同程序暂停和恢复的非阻塞函数函数作为存储桶沿过滤器链发送。核心结构这样的功能是：

function filter(r)
    -- Our first yield is to signal that we are ready to receive buckets.
    -- Before this yield, we can set up our environment, check for conditions,
    -- and, if we deem it necessary, decline filtering a request alltogether:
    if something_bad then
        return -- This would skip this filter.
    end
    -- Regardless of whether we have data to prepend, a yield MUST be called here.
    -- Note that only output filters can prepend data. Input filters must use the 
    -- final stage to append data to the content.
    coroutine.yield([optional header to be prepended to the content])

    -- After we have yielded, buckets will be sent to us, one by one, and we can 
    -- do whatever we want with them and then pass on the result.
    -- Buckets are stored in the global variable 'bucket', so we create a loop
    -- that checks if 'bucket' is not nil:
    while bucket ~= nil do
        local output = mangle(bucket) -- Do some stuff to the content
        coroutine.yield(output) -- Return our new content to the filter chain
    end

    -- Once the buckets are gone, 'bucket' is set to nil, which will exit the 
    -- loop and land us here. Anything extra we want to append to the content
    -- can be done by doing a final yield here. Both input and output filters 
    -- can append data to the content in this phase.
    coroutine.yield([optional footer to be appended to the content])
end

在Apache mod_lua中读取响应主体

1 个答案: