[WIP] - Handle exceptions

gateway/src/apicast/policy/custom_metrics/custom_metrics.lua

@@ -90,7 +90,11 @@ end
 
 -- report: Report the given usage information to the backend
 function _M.report(context, usage)
-  local backend = backend_client:new(context.service, http_ng_resty)
+  local backend, err = backend_client:new(context.service, http_ng_resty)
+  if not backend then
+    ngx.log(ngx.ERR, "failed to create backend_client, err: ", err)
+    return
+  end
   local reports = {}
   for key, value in pairs(usage.deltas) do
     local result = deepcopy(context.credentials)

gateway/src/apicast/policy/on_failed/on_failed.lua

@@ -1,3 +1,5 @@
+local get_phase = ngx.get_phase
+
 local _M  = require('apicast.policy').new('On failed', 'builtin')
 local new = _M.new
 
@@ -11,6 +13,12 @@ end
 function _M:export()
   return {
     policy_error_callback = function(policy_name, error_message)
+      local phase = get_phase()
+      -- skip calling plugins on body_filter/log phase as ngx.exit does not
+      -- exist in these phases
+      if phase == "body_filter" or phase == "log" then
+        return
+      end
       ngx.log(ngx.DEBUG, "Stop request because policy: '", policy_name, "' failed, error='", error_message, "'")
       ngx.exit(self.error_status_code)
     end

gateway/src/apicast/policy_chain.lua

@@ -216,6 +216,8 @@ local function call_chain(phase_name)
             if not status then
               if context.policy_error_callback then
                   context.policy_error_callback(self[i]._NAME, return_val)
+              else
+                error(return_val)
               end
               -- This is important because Openresty just died on error on init
               -- phase, and we should keep in this way.

gateway/src/apicast/proxy.lua

@@ -103,7 +103,7 @@ local function matched_patterns(matched_rules)
 end
 
 local function build_backend_client(self, service)
-  return assert(backend_client:new(service, self.http_ng_backend), 'missing backend')
+  return assert(backend_client:new(service, self.http_ng_backend))
 end
 
 function _M:authorize(context, service, usage, credentials, ttl)

t/apicast-policy-chains-crash.t

@@ -32,3 +32,34 @@ GET /test HTTP/1.1
 --- error_code: 200
 --- error_log
 Policy error_policy crashed in .new()
+
+
+
+=== TEST 2: policy chain with a policy that crashes on rewrite/access()
+Policies that crash during request phase should ternimate the request
+--- configuration
+{
+    "services": [
+      {
+        "id": 42,
+        "proxy": {
+            "policy_chain" : [
+              { "name" : "error_policy", "version" : "2.0.0" },
+              { "name" : "apicast.policy.echo" }
+            ]
+        }
+      }
+    ]
+}
+--- request
+GET /test
+--- ignore_response
+--- error_code: 500
+--- error_log eval
+[
+'lua entry thread aborted: runtime error:',
+'terminated in rewrite phase',
+'stack traceback:',
+" in function 'error'",
+": in function 'rewrite'",
+]

t/apicast.t

@@ -1310,3 +1310,89 @@ Authentication parameters missing
 
 
 
+=== TEST 36: works with BACKEND_ENDPOINT_OVERRIDE
+--- env eval
+(
+  'BACKEND_ENDPOINT_OVERRIDE' => "http://test_backend:$ENV{TEST_NGINX_SERVER_PORT}"
+)
+--- configuration
+{
+  "services" : [
+    {
+      "backend_version": 1,
+      "proxy": {
+        "api_backend": "http://test:$TEST_NGINX_SERVER_PORT/api-backend/",
+        "proxy_rules": [
+            { "pattern" : "/", "http_method" : "GET", "metric_system_name" : "hits", "delta" : 1}
+        ],
+        "policy_chain" : [
+          { "name" : "apicast.policy.apicast" }
+        ]
+      }
+    }
+  ]
+}
+--- upstream
+location /api-backend/ {
+  echo "yay, api backend!";
+}
+--- backend
+  location /transactions/authrep.xml {
+    content_by_lua_block {
+      content_by_lua_block { ngx.exit(200) }
+    }
+  }
+--- request
+GET /?user_key=value
+--- error_code: 200
+--- response_body
+yay, api backend!
+--- no_error_log
+[error]
+
+
+
+=== TEST 37: with invalid BACKEND_ENDPOINT_OVERRIDE
+Print the stacktrace, and terminate the request with 500 response code
+--- env eval
+(
+  'BACKEND_ENDPOINT_OVERRIDE' => 'invalid.backend.com'
+)
+--- configuration
+{
+  "services" : [
+    {
+      "backend_version": 1,
+      "proxy": {
+        "api_backend": "http://test:$TEST_NGINX_SERVER_PORT/api-backend/",
+        "proxy_rules": [
+            { "pattern" : "/", "http_method" : "GET", "metric_system_name" : "hits", "delta" : 1}
+        ],
+        "policy_chain" : [
+          { "name" : "apicast.policy.apicast" }
+        ]
+      }
+    }
+  ]
+}
+--- upstream
+location /api-backend/ {
+  echo "yay, api backend!";
+}
+--- backend
+  location /transactions/authrep.xml {
+    content_by_lua_block {
+       error('APIcast called authrep, but it should not have')
+    }
+  }
+--- request
+GET /?user_key=value
+--- error_code: 500
+--- error_log eval
+[
+'lua entry thread aborted: runtime error:',
+'missing scheme',
+'stack traceback:',
+" in function 'error'",
+": in function 'access'",
+]