Name

dynamic-upstream-module-lua - Lua bindings for dynamic-upstream-module

This module supports http and stream upstream types.

Healthcheck directives and lua api removed. Use ngx_dynamic_healthcheck module. Upstreams without zone directive are unsupported.

Build status

Dependencies

This module has several dependencies:

dynamic-upstream-module

Status

This library is production ready.

Description

This module provides Lua bindings to manage content of nginx upstreams.

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Install

Build nginx. All dependencies are downloaded automaticaly.

git clone [email protected]:ZigzagAK/ngx_dynamic_upstream_lua.git
cd ngx_dynamic_upstream_lua
./build.sh

Archive will be placed in the install folder after successful build.

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Configuration directives

disconnect_backup_if_primary_up

syntax: disconnect_backup_if_primary_up
default: none
context: stream/upstream

Disconnect from backup peers when primary peers becomes available.

disconnect_if_market_down

syntax: disconnect_if_market_down
default: none
context: stream/upstream

Disconnect peers when server is market down by healthcheck.

disconnect_on_exiting

syntax: disconnect_on_exiting
default: none
context: stream/upstream

Disconnect from upstream when nginx reloaded.

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Synopsis

http {
  lua_package_path "/path/to/lua-ngx-dynamic-upstream-lua/lib/?.lua;;";

  upstream backend {
    zone backend 1m;
    server 127.0.0.1:9090;
  }

  server {
    listen 8888;

    default_type text/plain;

    # curl "http://localhost:8888/backend/add?peer=127.0.0.1:9091&weight=1&max_fails=2&fail_timeout=30&max_conns=100"
    # curl "http://localhost:8888/backend/add?peer=127.0.0.1:9092&backup=1&weight=1&max_fails=2&fail_timeout=30&max_conns=100"
    location ~* ^/(.+)/add {
      set $upstream $1;
      content_by_lua_block {
        local upstream = require "ngx.dynamic_upstream"

        local peer = ngx.var.arg_peer
        local u = ngx.var.upstream

        local ok, err
        if ngx.var.arg_backup and ngx.var.arg_backup == 1 then
          ok, _, err = upstream.add_backup_peer(u, peer)
        else
          ok, _, err = upstream.add_primary_peer(u, peer)
        end

        if not ok then
          say("Failed to add peer " .. peer .. ": ", err)
          return
        end

        local peer_args = {
          weight       = ngx.var.arg_weight or 1,
          max_fails    = ngx.var.arg_max_fails or 2,
          fail_timeout = ngx.var.arg_fail_timeout or 5,
          max_conns    = ngx.var.arg_max_conns or 1,
          down         = 1
        }

        ok, _, err = upstream.update_peer(u, peer, peer_args)
        if not ok then
          ngx.say("Failed to update peer " .. peer .. " params, error: ", err)
          return
        end

        ngx.say("Added " .. peer .. " to " .. u .. " upstream")
      }
    }

    # remove peer
    # curl "http://localhost:8888/backend/remove?peer=127.0.0.1:9091"
    location ~* ^/(.+)/remove {
      set $upstream $1;
      content_by_lua_block {
        local upstream = require "ngx.dynamic_upstream"

        local peer = ngx.var.arg_peer
        local u = ngx.var.upstream

        local ok, _, err = upstream.remove_peer(u, peer)
        if not ok then
          ngx.say("Failed to remove peer " .. peer .. ": ", err)
          return
        end

        ngx.say("Removed " .. peer .. " from " .. u .. " upstream")
      }
    }

    # status page for all the peers:
    location = /status {
      content_by_lua_block {
        local upstream = require "ngx.dynamic_upstream"

        local ok, upstreams, err = upstream.get_upstreams()
        if not ok then
          ngx.say(err)
          ngx.exit(200)
        end

        local get_peers = function(u)
          local ok, peers, err = upstream.get_primary_peers(u)
          if not ok then
            ngx.say(err)
            ngx.exit(200)
          end
  
          local t = {}

          for _, peer in pairs(peers)
          do
            table.insert(t, peer)
          end

          ok, peers, err = upstream.get_backup_peers(u)
          if not ok then
            ngx.say(err)
            ngx.exit(200)
          end
  
          for _, peer in pairs(peers)
          do
            table.insert(t, peer)
          end

          return t
        end

        local tointeger = function (b) if b then return 1 else return 0 end end

        for _, u in pairs(upstreams)
        do
          ngx.say(u)

          for _, peer in pairs(get_peers(u))
          do
            local status = "up"
            if peer.down ~= nil then
              status = "down"
            end

            ngx.say("    server " .. peer.name .. " backup=" .. tointeger(peer.backup) .. " weight=" .. peer.weight .. " max_conns=" .. peer.max_conns .. " max_fails=" .. peer.max_fails .. " fail_timeout=" .. peer.fail_timeout .. " status=" .. status)
          end
        end
      }
    }
  }
}

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Packages

Package ngx.dynamic_upstream is used for manipulation http upstreams. Package ngx.dynamic_upstream.stream is used for manipulation stream upstreams.

Functionality of both packages are same.

Methods

get_upstreams

syntax: ok, upstreams, error = dynamic_upstream.get_upstreams()

context: *_by_lua*

Get table of upstreams.

Returns true and lua table on success, or false and a string describing an error otherwise.

get_peers

syntax: ok, servers, error = dynamic_upstream.get_peers(upstream)

context: *_by_lua*

Get table of servers in the upstream.

Returns true and lua table on success, or false and a string describing an error otherwise.

get_primary_peers

syntax: ok, peers, error = dynamic_upstream.get_primary_peers(upstream)

context: *_by_lua*

Get table of primary peers in the upstream.

Returns true and lua table on success, or false and a string describing an error otherwise.

get_backup_peers

syntax: ok, peers, error = dynamic_upstream.get_backup_peers(upstream)

context: *_by_lua*

Get table of backup peers in the upstream.

Returns true and lua table on success, or false and a string describing an error otherwise.