Writing tests for custom plugins, using "extra_lua_path"

[mikyll]

I'm trying to write and run some test for my custom plugins, but with no success.

Setup

Here's my setup:

• I cloned the APISIX repository (building from source) to /home/apisix/apisix_src;
• I clone test-nginx framework to /home/apisix/apisix_src/test-nginx;
• I downloaded every needed dependencies to run tests;
• I have etcd running in background (if I send a HTTP request to localhost:2379 I get the classic response "404 page not found").

Changes for Custom Plugin Test

I have a super simple custom plugin called custom-test, located at /home/apisix/apisix_src/apisix/plugins/custom/apisix/plugins/custom-test.lua:

local core = require("apisix.core")

local schema = {
    type = "object",
    properties = {
        debug = {
            description = "Enable logs",
            type = "boolean",
            default = false
        },
    },
}

local _M = {
    version = 0.1,
    priority = 5000,
    name = "custom-test",
    schema = schema,
}

function _M.check_schema(conf, schema_type)
    return core.schema.check(schema, conf)
end

function _M.rewrite(conf, ctx)
    if conf.debug then
        core.log.warn("\n\ncustom-test\n\n")
    end
    
    core.response.exit(200, { message = "custom-test" })
end

return _M

I have this config.yaml, located at /home/apisix/apisix_src/conf/config.yaml:

apisix:
    extra_lua_path: "/home/apisix/apisix_src/apisix/plugins/custom/?.lua"
    
    node_listen: 1984
    proxy_mode: "http&stream"
    stream_proxy:
        tcp:
            - 9100
    enable_resolv_search_opt: false

plugins:
    # [...] Other plugins 
    - custom-test

And I modified APISIX.pm (located at /home/apisix/apisix_src/t/APISIX.pm) file to remove the override of the config.yaml (referenced by variable $user_yaml_config), by commenting lines 97-105:

# $user_yaml_config = <<_EOC_;
# apisix:
#   node_listen: 1984
#   proxy_mode: http&stream
#   stream_proxy:
#     tcp:
#       - 9100
#   enable_resolv_search_opt: false
# _EOC_

Test

To test the correct loading of the custom plugin I use the following command, since in case of errors they fail due to the error entries in error.log:

cd /home/apisix/apisix_src
FLUSH_ETCD=1 TEST_NGINX_BINARY="/usr/local/openresty/nginx/sbin/nginx" prove -I. -Itest-nginx/lib -r "/home/apisix/apisix_src/t/plugin/echo.t"

Results

Without the changes to APISIX.pm (uncommented lines 97-105) the echo tests succeed:

/home/apisix/apisix_src/t/plugin/echo.t .. ok    
All tests successful.
Files=1, Tests=36,  4 wallclock secs ( 0.02 usr  0.00 sys +  0.54 cusr  0.15 csys =  0.71 CPU)
Result: PASS

With the changes I made to test the custom plugin I get these errors:

#   Failed test '/home/apisix/apisix_src/t/plugin/echo.t TEST 4: access - pattern "[error]" should not match any line in error.log but matches line "2024/06/25 10:40:16 [error] 1790#1790: *1 [lua] plugin.lua:138: load_plugin(): failed to load plugin [custom-test] err: module 'apisix.plugins.custom-test' not found:" (req 0)
#       no field package.preload['apisix.plugins.custom-test']
#       no file '/home/apisix/apisix_src/apisix/plugins/custom-test.lua'
#       no file '/home/apisix/apisix_src/apisix/plugins/custom-test/init.lua'
#       no file '/home/apisix/apisix_src/deps/share/lua/5.1/apisix/plugins/custom-test/init.lua'
#       no file '/home/apisix/apisix_src/deps/share/lua/5.1/apisix/plugins/custom-test.lua'
#       no file '/home/apisix/apisix_src/apisix/apisix/plugins/custom-test.lua'
#       no file '/home/apisix/apisix_src/t/apisix/plugins/custom-test.lua'
#       no file '/home/apisix/apisix_src/t/xrpc/apisix/plugins/custom-test.lua'
#       no file '/home/apisix/apisix_src/t/xrpc/apisix/plugins/custom-test/init.lua'
# '
#   at /home/apisix/apisix_src/test-nginx/lib/Test/Nginx/Socket.pm line 1356.

Which, appearently, suggest that APISIX is not searching the custom plugin by using the extra_lua_path config field...

Does anybody know what am I doing wrong or how can I fix this?

[mikyll]

Just found out why: APISIX.pm line 258

this makes extra_lua_path parameter in config.yaml useless 👀

As a simple workaround, I just moved the extra path from config.yaml file to the end of lua_package_path variable:

    lua_package_path "$apisix_home/?.lua;$apisix_home/?/init.lua;$apisix_home/deps/share/lua/5.1/?/init.lua;$apisix_home/deps/share/lua/5.1/?.lua;$apisix_home/apisix/?.lua;$apisix_home/t/?.lua;$apisix_home/t/xrpc/?.lua;$apisix_home/t/xrpc/?/init.lua;/home/apisix/apisix_src/apisix/plugins/custom/?.lua;;";