No easy way as far as I can see, a feature request for a simpler solution has been posted here:
Here’s a LUA workaround:
/etc/haproxy/anonymizeToken.lua:
local function anonymizeToken(url)
if url == nil then
return
end
url = url:gsub("token=[^&]+", "token=******")
return url
end
core.register_converters("anonymizeToken", anonymizeToken)
Config:
global
lua-load /etc/haproxy/anonymizeToken.lua
frontend blabla
log-format "%[capture.req.uri,lua.anonymizeToken]"