help request: OPA PLUGIN

[LuciaCabanillasRodriguez]

Description

Hi,

I’m setting up a route in APISIX where the URI is dynamic and depends on the user making the request. To achieve this, I’m using the OPA plugin. Within its result, I set a field called dynamic_metadata, which contains the URI the user is allowed to access.

However, I haven’t been able to retrieve this value from APISIX to include it as a variable in the URI. I tried configuring this using the proxy-rewrite plugin, but I haven’t achieved the desired result.

I would greatly appreciate any kind of help to resolve this issue.

Thanks!

Environment

• APISIX version (run apisix version): 3.10.0
• Operating system (run uname -a):
• OpenResty / Nginx version (run openresty -V or nginx -V):
• etcd version, if relevant (run curl http://127.0.0.1:9090/v1/server_info): 3.5.0
• APISIX Dashboard version, if relevant: 3.0.1
• Plugin runner version, for issues related to plugin runners:
• LuaRocks version, for installation issues (run luarocks --version):

[kayx23]

Please see if radixtree_uri_with_parameter router option helps: https://docs.api7.ai/apisix/reference/router-options#radixtree_uri_with_parameter

[LuciaCabanillasRodriguez]

Thank you very much for your comment! Just something like that I was trying, the problem I think is that not all the OPA response is saved in the ctx so if I want to access a particular field of the OPA result I can not access as easily as in the example ctx.curr_req_matched.user_id

[kayx23]

not all the OPA response is saved in the ctx

Perhaps you could use the serverless function to parse the response and register the value into a variable, if appropriate? For instance https://docs.api7.ai/hub/serverless-functions#register-custom-variables

[LuciaCabanillasRodriguez]

And how could I access that field in the OPA result?
I was trying something like that but I am not very clear on how to get that value:

"proxy-rewrite": {
      "uri": "/${upstream_uri}"
    },
    "serverless-pre-function": {
      "functions": [
        "return function(conf, ctx)\n  local core = require(\"apisix.core\")\n  core.ctx.register_var(\"opa_query\", function(ctx)\n    if ctx.var.opa_result and ctx.var.opa_result.result and ctx.var.opa_result.result.dynamic_metadata and ctx.var.opa_result.result.dynamic_metadata.query then\n      return ctx.var.opa_result.result.dynamic_metadata.query.q\n    end\n    return nil\n  end)\n  local query_q = ctx.var.opa_query\n  if query_q then\n    local encoded_q = core.utils.url_escape(\"publisher==\\\"\" .. query_q .. \"\\\"\")\n    ctx.var.upstream_uri =

Thanks! :)