function _M.set_by_route()

in apisix/upstream.lua [268:405]

• 109 lines of code
• 24 McCabe index (conditional complexity)

function _M.set_by_route(route, api_ctx)
    if api_ctx.upstream_conf then
        
        return
    end

    local up_conf = api_ctx.matched_upstream
    if not up_conf then
        return 503, "missing upstream configuration in Route or Service"
    end
    

    if up_conf.service_name then
        if not discovery then
            return 503, "discovery is uninitialized"
        end
        if not up_conf.discovery_type then
            return 503, "discovery server need appoint"
        end

        local dis = discovery[up_conf.discovery_type]
        if not dis then
            local err = "discovery " .. up_conf.discovery_type .. " is uninitialized"
            return 503, err
        end

        local new_nodes, err = dis.nodes(up_conf.service_name, up_conf.discovery_args)
        if not new_nodes then
            return HTTP_CODE_UPSTREAM_UNAVAILABLE, "no valid upstream node: " .. (err or "nil")
        end

        local same = upstream_util.compare_upstream_node(up_conf, new_nodes)
        if not same then
            local pass, err = core.schema.check(core.schema.discovery_nodes, new_nodes)
            if not pass then
                return HTTP_CODE_UPSTREAM_UNAVAILABLE, "invalid nodes format: " .. err
            end

            local new_up_conf = core.table.clone(up_conf)
            new_up_conf.nodes = new_nodes
            new_up_conf.original_nodes = up_conf.nodes

            core.log.info("discover new upstream from ", up_conf.service_name, ", type ",
                          up_conf.discovery_type, ": ",
                          core.json.delay_encode(new_up_conf, true))

            local parent = up_conf.parent
            if parent.value.upstream then
                
                parent.value.upstream = new_up_conf
            else
                parent.value = new_up_conf
            end
            up_conf = new_up_conf
        end
    end

    local id = up_conf.parent.value.id
    local conf_version = up_conf.parent.modifiedIndex
    
    
    set_directly(api_ctx, id, conf_version .. "#" .. tostring(up_conf), up_conf)

    local nodes_count = up_conf.nodes and #up_conf.nodes or 0
    if nodes_count == 0 then
        release_checker(up_conf.parent)
        return HTTP_CODE_UPSTREAM_UNAVAILABLE, "no valid upstream node"
    end

    if not is_http then
        local ok, err = fill_node_info(up_conf, nil, true)
        if not ok then
            return 503, err
        end

        local scheme = up_conf.scheme
        if scheme == "tls" then
            local ok, err = set_stream_upstream_tls()
            if not ok then
                return 503, err
            end

            local sni = apisix_ssl.server_name()
            if sni then
                ngx_var.upstream_sni = sni
            end
        end

        return
    end

    set_upstream_scheme(api_ctx, up_conf)

    local ok, err = fill_node_info(up_conf, api_ctx.upstream_scheme, false)
    if not ok then
        return 503, err
    end

    local checker = fetch_healthchecker(up_conf)
    api_ctx.up_checker = checker

    local scheme = up_conf.scheme
    if (scheme == "https" or scheme == "grpcs") and up_conf.tls then

        local client_cert, client_key
        if up_conf.tls.client_cert_id then
            client_cert = api_ctx.upstream_ssl.cert
            client_key = api_ctx.upstream_ssl.key
        else
            client_cert = up_conf.tls.client_cert
            client_key = up_conf.tls.client_key
        end

        
        local sni = api_ctx.var.upstream_host
        local cert, err = apisix_ssl.fetch_cert(sni, client_cert)
        if not ok then
            return 503, err
        end

        local key, err = apisix_ssl.fetch_pkey(sni, client_key)
        if not ok then
            return 503, err
        end

        if scheme == "grpcs" then
            api_ctx.upstream_grpcs_cert = cert
            api_ctx.upstream_grpcs_key = key
        else
            local ok, err = set_upstream_tls_client_param(cert, key)
            if not ok then
                return 503, err
            end
        end
    end

    return
end