Logging policy

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Conditions for the limits of the rate-limit policy [PR #839](https://github.com/3scale/apicast/pull/839)
 - `bin/apicast console` to start Lua REPL with APIcast code loaded [PR #853](https://github.com/3scale/apicast/pull/853)
 - Liquid Context Debugging policy. It's a policy only meant for debugging purposes, returns the context available when evaluating liquid [PR #849](https://github.com/3scale/apicast/pull/849)
+- Logging policy. It allows to enable/disable access logs per service [PR #856](https://github.com/3scale/apicast/pull/856), [THREESCALE-1148](https://issues.jboss.org/browse/THREESCALE-1148)
 
 ### Changed
 

gateway/conf/nginx.conf.liquid

@@ -120,7 +120,8 @@ http {
 
   server {
 
-    access_log {{ access_log_file | default: "/dev/stdout" }} time;
+    set $access_logs_enabled '1';
+    access_log {{ access_log_file | default: "/dev/stdout" }} time if=$access_logs_enabled;
 
     {%- assign http_port = port.apicast | default: 8080 %}
     {%- assign https_port = env.APICAST_HTTPS_PORT %}

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

@@ -0,0 +1,19 @@
+{
+  "$schema": "http://apicast.io/policy-v1/schema#manifest#",
+  "name": "Logging",
+  "summary": "Controls logging",
+  "description": [
+    "Controls logging. It allows to enable and disable access logs per ",
+    "service."
+  ],
+  "version": "builtin",
+  "configuration": {
+    "type": "object",
+    "properties": {
+      "enable_access_logs": {
+        "description": "Whether to enable access logs for the service",
+        "type": "boolean"
+      }
+    }
+  }
+}

gateway/src/apicast/policy/logging/init.lua

@@ -0,0 +1 @@
+return require('logging')

gateway/src/apicast/policy/logging/logging.lua

@@ -0,0 +1,40 @@
+--- Logging policy
+
+local _M  = require('apicast.policy').new('Logging Policy')
+
+local new = _M.new
+
+local default_enable_access_logs = true
+
+-- Defined in ngx.conf.liquid and used in the 'access_logs' directive.
+local ngx_var_access_logs_enabled = 'access_logs_enabled'
+
+-- Returns the value for the ngx var above from a boolean that indicates
+-- whether access logs are enabled or not.
+local val_for_ngx_var ={
+  [true] = '1',
+  [false] = '0'
+}
+
+function _M.new(config)
+  local self = new(config)
+
+  local enable_access_logs = config.enable_access_logs
+  if enable_access_logs == nil then -- Avoid overriding when it's false.
+    enable_access_logs = default_enable_access_logs
+  end
+
+  if not enable_access_logs then
+    ngx.log(ngx.DEBUG, 'Disabling access logs')
+  end
+
+  self.enable_access_logs_val = val_for_ngx_var[enable_access_logs]
+
+  return self
+end
+
+function _M:log()
+  ngx.var[ngx_var_access_logs_enabled] = self.enable_access_logs_val
+end
+
+return _M

spec/policy/logging/logging_spec.lua

@@ -0,0 +1,39 @@
+local LoggingPolicy = require('apicast.policy.logging')
+
+describe('Logging policy', function()
+  describe('.log', function()
+    before_each(function()
+      ngx.var = {}
+    end)
+
+    context('when access logs are enabled', function()
+      it('sets ngx.var.access_logs_enabled to "1"', function()
+        local logging = LoggingPolicy.new({ enable_access_logs = true })
+
+        logging:log()
+
+        assert.equals('1', ngx.var.access_logs_enabled)
+      end)
+    end)
+
+    context('when access logs are disabled', function()
+      it('sets ngx.var.enable_access_logs to "0"', function()
+        local logging = LoggingPolicy.new({ enable_access_logs = false })
+
+        logging:log()
+
+        assert.equals('0', ngx.var.access_logs_enabled)
+      end)
+    end)
+
+    context('when access logs are not configured', function()
+      it('enables them by default by setting ngx.var.enable_access_logs to "1"', function()
+        local logging = LoggingPolicy.new({})
+
+        logging:log()
+
+        assert.equals('1', ngx.var.access_logs_enabled)
+      end)
+    end)
+  end)
+end)

t/apicast-policy-logging.t

@@ -0,0 +1,133 @@
+use lib 't';
+use Test::APIcast::Blackbox 'no_plan';
+
+# Test::Nginx does not allow to grep access logs, so we redirect them to
+# stderr to be able to use "grep_error_log" by setting APICAST_ACCESS_LOG_FILE
+$ENV{APICAST_ACCESS_LOG_FILE} = "$Test::Nginx::Util::ErrLogFile";
+
+run_tests();
+
+__DATA__
+
+=== TEST 1: Enables access logs when configured to do so
+--- configuration
+{
+  "services": [
+    {
+      "id": 42,
+      "proxy": {
+        "policy_chain": [
+          {
+            "name": "apicast.policy.logging",
+            "configuration": {
+              "enable_access_logs": true
+            }
+          },
+          {
+            "name": "apicast.policy.upstream",
+            "configuration":
+              {
+                "rules": [ { "regex": "/", "url": "http://echo" } ]
+              }
+          }
+        ]
+      }
+    }
+  ]
+}
+--- upstream
+  location / {
+     content_by_lua_block {
+       ngx.say('yay, api backend');
+     }
+  }
+--- request
+GET /
+--- error_code: 200
+--- grep_error_log eval
+qr/"GET \W+ HTTP\/1.1" 200/
+--- grep_error_log_out
+"GET / HTTP/1.1" 200
+--- no_error_log
+[error]
+
+=== TEST 2: Disables access logs when configured to do so
+--- configuration
+{
+  "services": [
+    {
+      "id": 42,
+      "proxy": {
+        "policy_chain": [
+          {
+            "name": "apicast.policy.logging",
+            "configuration": {
+              "enable_access_logs": false
+            }
+          },
+          {
+            "name": "apicast.policy.upstream",
+            "configuration":
+              {
+                "rules": [ { "regex": "/", "url": "http://echo" } ]
+              }
+          }
+        ]
+      }
+    }
+  ]
+}
+--- upstream
+  location / {
+     content_by_lua_block {
+       ngx.say('yay, api backend');
+     }
+  }
+--- request
+GET /
+--- error_code: 200
+--- grep_error_log eval
+qr/"GET \W+ HTTP\/1.1" 200/
+--- grep_error_log_out
+--- no_error_log
+[error]
+
+=== TEST 3: Enables access logs by default when the policy is included
+--- configuration
+{
+  "services": [
+    {
+      "id": 42,
+      "proxy": {
+        "policy_chain": [
+          {
+            "name": "apicast.policy.logging",
+            "configuration": { }
+          },
+          {
+            "name": "apicast.policy.upstream",
+            "configuration":
+              {
+                "rules": [ { "regex": "/", "url": "http://echo" } ]
+              }
+          }
+        ]
+      }
+    }
+  ]
+}
+--- upstream
+  location / {
+     content_by_lua_block {
+       ngx.say('yay, api backend');
+     }
+  }
+--- request
+GET /
+--- error_code: 200
+--- grep_error_log eval
+qr/"GET \W+ HTTP\/1.1" 200/
+--- grep_error_log_out
+"GET / HTTP/1.1" 200
+--- no_error_log
+[error]