fix(mysql): add default values

Author: dszakallas

lib/instrumentations/mysql.js

@@ -24,9 +24,9 @@ function composeAgentData (config, args) {
   }
   return {
     protocol: consts.PROTOCOLS.MYSQL,
-    url: connectionURI || undefined,
+    url: connectionURI || 'unknown',
     host: config.host || 'unknown',
-    method: utils.tryParseSql(args[0] || '')
+    method: utils.tryParseSql(args[0]) || 'unknown'
   }
 }
 

lib/instrumentations/mysql.spec.js

@@ -83,7 +83,7 @@ describe('The mysql wrapper', function () {
           host: 'unknown',
           method: 'SELECT',
           protocol: 'mysql',
-          url: undefined
+          url: 'unknown'
         })
       done()
     })
@@ -129,7 +129,7 @@ describe('The mysql wrapper', function () {
           host: 'unknown',
           method: 'SELECT',
           protocol: 'mysql',
-          url: undefined
+          url: 'unknown'
         })
       done()
     })