MEDIUM: lua: Add ability for actions to intercept HTTP messages
It is now possible to intercept HTTP messages from a lua action and reply to
clients. To do so, a reply object must be provided to the function
txn:done(). It may contain a status code with a reason, a header list and a
body. By default, if an empty reply object is used, an empty 200 response is
returned. If no reply is passed when txn:done() is called, the previous
behaviour is respected, the transaction is terminated and nothing is returned to
the client. The same is done for TCP streams. When txn:done() is called, the
action is terminated with the code ACT_RET_DONE on success and ACT_RET_ERR on
error, interrupting the message analysis.
The reply object may be created for the lua, by hand. Or txn:reply() may be
called. If so, this object provides some methods to fill it:
* Reply:set_status(<status> [ <reason>]) : Set the status and optionally the
reason. If no reason is provided, the default one corresponding to the status
code is used.
* Reply:add_header(<name>, <value>) : Add a header. For a given name, the
values are stored in an ordered list.
* Reply:del_header(<name>) : Removes all occurrences of a header name.
* Reply:set_body(<body>) : Set the reply body.
Here are some examples, all doing the same:
-- ex. 1
txn:done{
status = 400,
reason = "Bad request",
headers = {
["content-type"] = { "text/html" },
["cache-control"] = { "no-cache", "no-store" },
},
body = "<html><body><h1>invalid request<h1></body></html>"
}
-- ex. 2
local reply = txn:reply{
status = 400,
reason = "Bad request",
headers = {
["content-type"] = { "text/html" },
["cache-control"] = { "no-cache", "no-store" }
},
body = "<html><body><h1>invalid request<h1></body></html>"
}
txn:done(reply)
-- ex. 3
local reply = txn:reply()
reply:set_status(400, "Bad request")
reply:add_header("content-length", "text/html")
reply:add_header("cache-control", "no-cache")
reply:add_header("cache-control", "no-store")
reply:set_body("<html><body><h1>invalid request<h1></body></html>")
txn:done(reply)
2 files changed