cannot send query in the current context: nil: nil: nil.

[yjdwbj]

luarocks install lua-resty-postgres

....

    local db = pgsql:new()
    db:set_timeout(3000)
    local ok,err = db:connect({database= config.pgsql.database ,
                              host = config.pgsql.host,
                              port = config.pgsql.port,
                              user = config.pgsql.user,
                              password = config.pgsql.password,compact = false
                          })
    if not ok then
        ngx.say(err)
    end
    -- db:set_timeout(conf.timeout) -- 1 sec

    -- local ok, err, errno, sqlstate = db:connect(conf.pgsql)
    -- local ok, err, errno, sqlstate = db:connect()
    -- if not ok then
    --     ngx.say("failed to connect: ", err, ": ", errno, " ", sqlstate)
    --     return
    -- end

    -- ngx.log(ngx.ERR, "connected to pgsql, reused_times:", db:get_reused_times(), " sql:", sql)

    -- db:query("SET NAMES utf8")
    ngx.log(ngx.ERR,"sql is ----- ",sql)
    local res, err, errno, sqlstate = db:query(sql)
    db:set_keepalive(0,100)
    if not res then
        ngx.log(ngx.ERR, "bad result: ", err, ": ", errno, ": ", sqlstate, ".")
    end

    -- local ok, err = db:set_keepalive(conf.pool_config.max_idle_timeout, conf.pool_config.pool_size)
    -- if not ok then
    --     ngx.say("failed to set keepalive: ", err)
    -- end

    return res, err, errno, sqlstate

db.lua:77: query(): bad result: failed to send query: cannot send query in the current context: nil: nil: nil.,