THREESCALE-6552 - RFE

- Sharing upstream.uri in the liquid context as "upstream"
- Unit + integration tests updated

gateway/src/apicast/policy/maintenance_mode/README.md

@@ -10,7 +10,9 @@ and message. It's useful for maintenance periods or to temporarily block an API.
 | status (integer, _optional_) | 503                               | Response code    |
 | message (string, _optional_) | Service Unavailable - Maintenance | Response message |
 
-## Example Configuration
+## Examples Configuration
+
+- Custom response message
 ```json
 {
   "name": "maintenance-mode",
@@ -20,3 +22,25 @@ and message. It's useful for maintenance periods or to temporarily block an API.
   }
 }
 ```
+- Apply Maintenance Mode for a specific upstream
+```json
+{
+    "name": "maintenance_mode",
+    "configuration": {
+      "condition": {
+        "operations": [
+          {
+            "left_type": "liquid",
+            "right_type": "plain",
+            "left": "{{ upstream.host }}{{ upstream.path }}",
+            "right": "echo-api.3scale.net/test",
+            "op": "=="
+          }
+        ],
+        "combine_op": "and"
+      },
+      "status": 503,
+      "message": "Echo API /test is currently Unavailable"
+    }
+}
+```

gateway/src/apicast/policy/maintenance_mode/apicast-policy.json

@@ -2,11 +2,79 @@
   "$schema": "http://apicast.io/policy-v1.1/schema#manifest#",
   "name": "Maintenance Mode",
   "summary": "Rejects incoming requests. Useful for maintenance periods.",
-  "description": ["A policy which allows you reject incoming requests with a specified status code and message.",
-    "It's useful for maintenance periods or to temporarily block an API."
+  "description": [
+    "A policy which allows you to reject incoming requests with a specified status code and message. ",
+    "It's useful for maintenance periods or to temporarily block an API. \n",
+    "It allows to select a list of Upstream URLs for which to enable the maintenance mode."
   ],
   "version": "builtin",
   "configuration": {
+    "definitions": {
+      "operation": {
+        "type": "object",
+        "$id": "#/definitions/operation",
+        "properties": {
+          "left": {
+            "type": "string"
+          },
+          "op": {
+            "description": "Operation to apply. The matches op supports PCRE (Perl compatible regular expressions)",
+            "type": "string",
+            "enum": [
+              "==",
+              "!=",
+              "matches"
+            ]
+          },
+          "right": {
+            "type": "string"
+          },
+          "left_type": {
+            "description": "How to evaluate 'left'",
+            "type": "string",
+            "default": "plain",
+            "oneOf": [
+              {
+                "enum": [
+                  "plain"
+                ],
+                "title": "Evaluate 'left' as plain text."
+              },
+              {
+                "enum": [
+                  "liquid"
+                ],
+                "title": "Evaluate 'left' as liquid."
+              }
+            ]
+          },
+          "right_type": {
+            "description": "How to evaluate 'right'",
+            "type": "string",
+            "default": "plain",
+            "oneOf": [
+              {
+                "enum": [
+                  "plain"
+                ],
+                "title": "Evaluate 'right' as plain text."
+              },
+              {
+                "enum": [
+                  "liquid"
+                ],
+                "title": "Evaluate 'right' as liquid."
+              }
+            ]
+          }
+        },
+        "required": [
+          "left",
+          "op",
+          "right"
+        ]
+      }
+    },
     "type": "object",
     "properties": {
       "status": {
@@ -23,6 +91,32 @@
         "type": "string",
         "description": "Content-Type header for the response",
         "default": "text/plain; charset=utf-8"
+      },
+      "condition": {
+        "type": "object",
+        "title": "Condition",
+        "required": [
+          "combine_op",
+          "operations"
+        ],
+        "properties": {
+          "combine_op": {
+            "title": "Combine operation",
+            "type": "string",
+            "default": "and",
+            "enum": [
+              "and",
+              "or"
+            ]
+          },
+          "operations": {
+            "type": "array",
+            "items": {
+              "$ref": "#/definitions/operation"
+            },
+            "minItems": 1
+          }
+        }
       }
     }
   }

gateway/src/apicast/policy/maintenance_mode/maintenance_mode.lua

@@ -1,4 +1,4 @@
--- This is a simple policy. It allows you reject incoming requests with a
+-- This policy allows to reject incoming requests with a
 -- specified status code and message.
 -- It's useful for maintenance periods or to temporarily block an API
 
@@ -11,6 +11,9 @@ local default_status_code = 503
 local default_message = "Service Unavailable - Maintenance"
 local default_message_content_type = "text/plain; charset=utf-8"
 
+local Condition = require('apicast.conditions.condition')
+local Operation = require('apicast.conditions.operation')
+
 function _M.new(configuration)
   local policy = new(configuration)
 
@@ -19,20 +22,54 @@ function _M.new(configuration)
   policy.message_content_type = default_message_content_type
 
   if configuration then
+    policy.maintenance_upstreams = configuration.upstreams
     policy.status_code = tonumber(configuration.status) or policy.status_code
     policy.message = configuration.message or policy.message
     policy.message_content_type = configuration.message_content_type or policy.message_content_type
   end
 
+  policy:load_condition(configuration)
   return policy
 end
 
-function _M:rewrite()
+function _M:load_condition(config)
+  if not config or not config.condition then
+    return
+  end
+
+  local operations = {}
+  for _, operation in ipairs(config.condition.operations or {}) do
+    table.insert( operations,
+      Operation.new(
+        operation.left,
+        operation.left_type or default_template_type,
+        operation.op,
+        operation.right,
+        operation.right_type or default_template_type))
+  end
+  self.condition = Condition.new( operations, config.condition.combine_op or default_combine_op)
+end
+
+function set_maintenance_mode(self)
   ngx.header['Content-Type'] = self.message_content_type
   ngx.status = self.status_code
   ngx.say(self.message)
 
   return ngx.exit(ngx.status)
 end
 
+function _M:access(context)
+  -- Before the condition was not set, so the maintenance mode when condition is
+  -- nil should work.
+  if self.condition == nil then
+    return set_maintenance_mode(self)
+  end
+
+  context.upstream = context.route_upstream or context:get_upstream() or {}
+  context.upstream = context.upstream.uri or context.upstream
+  if self.condition:evaluate(context) then
+    return set_maintenance_mode(self)
+  end
+end
+
 return _M

gateway/src/apicast/policy/upstream/upstream.lua

@@ -58,6 +58,10 @@ function _M:rewrite(context)
   end
 end
 
+function _M:access(context)
+  context.route_upstream = context[self] or context.route_upstream
+end
+
 function _M:content(context)
   local upstream = context[self]