bug: coroutine.wrap:20: API disabled in the context of log_by_lua error in Batch Processor

[sshniro]

Hi,

When using the batch processor inside the _M.log phase the system throws the following error.

This happens when I use core.schema.check(schema, config) inside the batch processor.
If I use a simple validation (if/else) then the workflow is working without an error.

2020/03/02 15:36:40 [error] 5155#5155: *237 failed to run log_by_lua*: coroutine.wrap:20: API disabled in the context of log_by_lua*
stack traceback:
	[C]: in function 'create'
	coroutine.wrap:20: in function '_get_loader'
	...one3/incubator-apisix//deps/share/lua/5.1/jsonschema.lua:197: in function 'create_obj_fun'
	...che/clone3/incubator-apisix/lua/apisix/core/lrucache.lua:66: in function 'cached_validator'
	...pache/clone3/incubator-apisix/lua/apisix/core/schema.lua:34: in function 'check'
	.../incubator-apisix/lua/apisix/plugins/batch-processor.lua:110: in function 'new'
	...lone3/incubator-apisix/lua/apisix/plugins/udp-logger.lua:118: in function 'phase_fun'
	/home/nirojan/apache/clone3/incubator-apisix/lua/apisix.lua:154: in function 'run_plugin'
	/home/nirojan/apache/clone3/incubator-apisix/lua/apisix.lua:459: in function 'http_log_phase'
	log_by_lua(nginx.conf:191):2: in main chunk while logging request, client: 127.0.0.1, server: , request: "GET /?param1=value HTTP/1.1", upstream: "http://127.0.0.1:80/?param1=value", host: "127.0.0.1:9080"

Is this a limitation? Some guidance would be helpful.

[sshniro]

@membphis I guess APISIX is not allowing to access the JSON schema validator during log phase. Is this due to any performance gain? or shall I use normal validation instead of using the jsonschema?

[membphis]

In jsonschema, the compiled Lua code is generated by using yield, but the yield operation is not supported in log_phase.

I suggest modifying the https://github.com/iresty/jsonschema implementation to avoid using the yield method.

https://github.com/iresty/jsonschema/blob/ddd76d719cb102a0db2c44fe207745a9c3e53452/lib/jsonschema.lua#L141

[sshniro]

I would like to start working on this issue, as it is blocking #965 and #1070 for batch processing. Will post the question in the associated repo.

[membphis]

@sshniro api7/jsonschema#8

I have created an issue, if you would like to do this job, please leave a message on this issue. I will assign this issue to you.

[sshniro]

Closing this issue, as it's fixed by #8