serverless

Description

There are two plug-ins for serverless, namely serverless-pre-function and serverless-post-function.

The former runs at the beginning of the specified phase, while the latter runs at the end of the specified phase.

Both plug-ins receive the same parameters.

Attributes

NameTypeRequirementDefaultValidDescription
phasestringoptional[“access”][“rewrite”, “access”, “header_filter”, “body_filter”, “log”, “before_proxy”]
functionsarray[string]requiredA list of functions that are specified to run is an array type, which can contain either one function or multiple functions, executed sequentially.

Note that only function is accepted here, not other types of Lua code. For example, anonymous functions are legal: 

  1. return function()
  2.     ngx.log(ngx.ERR, 'one')
  3. end

Closure is also legal:

  1. local count = 1
  2. return function()
  3.     count = count + 1
  4.     ngx.say(count)
  5. end

But code that is not a function type is illegal:

  1. local count = 1
  2. ngx.say(count)

Since v2.6, we pass the conf and ctx as the first two arguments to the servelss function, like a regular plugin.

Prior to v2.12.0, the phase before_proxy used to be called balancer. Considering that this method actually runs after access and before the request goes upstream, and has nothing to do with balancer, the new naming would be more appropriate.

How To Enable

Here’s an example, enable the serverless plugin on the specified route:

  1. curl http://127.0.0.1:9080/apisix/admin/routes/1  -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
  2. {
  3.     "uri": "/index.html",
  4.     "plugins": {
  5.         "serverless-pre-function": {
  6.             "phase": "rewrite",
  7.             "functions" : ["return function() ngx.log(ngx.ERR, \"serverless pre function\"); end"]
  8.         },
  9.         "serverless-post-function": {
  10.             "phase": "rewrite",
  11.             "functions" : ["return function(conf, ctx) ngx.log(ngx.ERR, \"match uri \", ctx.curr_req_matched and ctx.curr_req_matched._path); end"]
  12.         }
  13.     },
  14.     "upstream": {
  15.         "type": "roundrobin",
  16.         "nodes": {
  17.             "127.0.0.1:1980": 1
  18.         }
  19.     }
  20. }'

Test Plugin

Use curl to access:

  1. curl -i http://127.0.0.1:9080/index.html

Then you will find the message ‘serverless pre-function’ and ‘match uri /index.html’ in the error.log, which indicates that the specified function is in effect.

Disable Plugin

When you want to disable the serverless plugin, it is very simple, you can delete the corresponding json configuration in the plugin configuration, no need to restart the service, it will take effect immediately:

  1. curl http://127.0.0.1:9080/apisix/admin/routes/1  -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
  2. {
  3.     "methods": ["GET"],
  4.     "uri": "/index.html",
  5.     "upstream": {
  6.         "type": "roundrobin",
  7.         "nodes": {
  8.             "127.0.0.1:1980": 1
  9.         }
  10.     }
  11. }'

The serverless plugin has been disabled now. It works for other plugins.