DataScript: avi.http.get_reqvar

DataScript

Function avi.http.get_reqvar()
Description Gets (reads) data stored in a variable via the avi.http.set_reqvar() function. These variables have scope across the HTTP_REQ and HTTP_RESP events. Typically this function is used when data must be stored (set) in the HTTP request event, and retrieved (get) during the HTTP response event.  The lifetime of data stored in the reqvar functions are limited to the HTTP request/response transaction.  After the response completes, the variable is automatically unset. Any Lua value can be stored within this variable. This variable type may be used by other components within Avi Vantage, not just DataScripts. Avi supports three levels of storing data in variables.
  1. For variable data that is only required during the current event, simply map the variable to the data. 
    var = 1
if var == 2 then ...
  2. For variables that must remain persistent across the HTTP request and response events (a complete flow), use the avi.http.set_reqvar() and avi.http.get_reqvar() functions.
  3. For variable data that needs to be saved across connections or mirrored to other Service Engines supporting the virtual service, use avi.vs.table_insert()
Events HTTP_REQ HTTP_RESP
Parameter Name: Specify the name of the variable to be declared. The name is a string and must be in quotation marks.
Returns If data exists, returns the data stored in the variable.  Else returns nil.
Version 17.1+
Related avi.http.set_reqvar() Retrieves the stored variable from the avi.http.set_reqvar function
Example HTTP_REQ event: 
avi.http.set_reqvar("foo", 10)
HTTP_RESP event: 
if avi.http.get_reqvar("foo") > 5 then
   avi.vs.log("Foo=" .. avi.http.get_reqvar("foo"))
end

Note: This API is not supported in the events SSL_PRECONNECT, SSL_CLIENTHELLO, and SSL_HANDSHAKE_DONE.