refactor: improve JWT validation logging and response handling

Author: infezek

nginx.conf

@@ -12,15 +12,19 @@ http {
         location /api {
             content_by_lua_block {
                 local libjwt = require("resty.libjwt")
-                local valid, err = libjwt.validate({
-                        ["header_token"] = "Authorization",
-                        ["jwks_files"] = { "/usr/share/tokens/jwks.json"},
+                local cjson = require("cjson.safe")
+                local claim, err = libjwt.validate({
+                    ["header_token"] = "Authorization",
+                    ["jwks_files"] = { "....",  "/usr/share/tokens/jwks.json"},
                 })
-                if err ~= "" then
+                if err and err ~= "" then
+                    ngx.log(ngx.ERR, "JWT Validation Error: " .. err)
                     return ngx.say(err)
                 end
-                if valid then
-                    return ngx.say("OK")
+                if claim then
+                    local claim_str = cjson.encode(claim) or "Invalid Claim"
+                    ngx.log(ngx.ERR, "JWT Claims: " .. claim_str)
+                    return ngx.say(claim_str)
                 end
                 return ngx.say("Unauthorized")
             }