feat(cdk): Tokens can be converted to strings (#518)

Tokens (such as resource attributes) can now be implicitly converted into strings. This allows using any late-bound CloudFormation value where strings can be used in the host language, and the native string facilities of the host language can be used as well to further process strings. The process is reversed by the resolve() function during synthesis, which will split the string up again into string literals and CloudFormation intrinsics (combined by `{Fn::Join}`). Introduces `CloudFormationJSON.stringify` to produce a similar result, but used for JSON-encoding of complex objects that may contain Tokens. This is used in JSON-encoded policy statements, CloudFormation actions, state machine definitions, and more. Additional changes: - Add a VSCode launch config (with a helper script) to directly debug a unit test from within the IDE. This allows setting breakpoints. - SecretParameter no longer duckily implements Token; this will not work in other jsii languages anyway. - Nested `FnConcat` structures will be flattened in the CloudFormation output. Fixes #24 and #168.
aws · Aug 15, 2018 · 939015a · 939015a
1 parent f0e7bb5
commit 939015a
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diff --git a/packages/@aws-cdk/aws-cloudwatch/lib/dashboard.ts b/packages/@aws-cdk/aws-cloudwatch/lib/dashboard.ts
@@ -1,4 +1,4 @@
-import { Construct, Stack, Token, tokenAwareJsonify } from "@aws-cdk/cdk";
+import { CloudFormationJSON, Construct, Stack, Token } from "@aws-cdk/cdk";
 import { cloudformation } from './cloudwatch.generated';
 import { Column, Row } from "./layout";
 import { IWidget } from "./widget";
@@ -33,7 +33,7 @@ export class Dashboard extends Construct {
             dashboardBody: new Token(() => {
                 const column = new Column(...this.rows);
                 column.position(0, 0);
-                return tokenAwareJsonify({ widgets: column.toJson() });
+                return CloudFormationJSON.stringify({ widgets: column.toJson() });
             })
         });
     }

diff --git a/packages/@aws-cdk/aws-cloudwatch/test/integ.alarm-and-dashboard.expected.json b/packages/@aws-cdk/aws-cloudwatch/test/integ.alarm-and-dashboard.expected.json
@@ -7,6 +7,11 @@
       "Type": "AWS::CloudWatch::Alarm",
       "Properties": {
         "ComparisonOperator": "GreaterThanOrEqualToThreshold",
+        "EvaluationPeriods": 3,
+        "MetricName": "ApproximateNumberOfMessagesVisible",
+        "Namespace": "AWS/SQS",
+        "Period": 300,
+        "Threshold": 100,
         "Dimensions": [
           {
             "Name": "QueueName",
@@ -18,41 +23,55 @@
             }
           }
         ],
-        "EvaluationPeriods": 3,
-        "MetricName": "ApproximateNumberOfMessagesVisible",
-        "Namespace": "AWS/SQS",
-        "Period": 300,
-        "Statistic": "Average",
-        "Threshold": 100
+        "Statistic": "Average"
       }
     },
     "DashCCD7F836": {
       "Type": "AWS::CloudWatch::Dashboard",
       "Properties": {
-        "DashboardName": "aws-cdk-cloudwatch-DashCCD7F836",
         "DashboardBody": {
-          "Fn::Sub": [
-            "{\"widgets\":[{\"type\":\"text\",\"width\":6,\"height\":2,\"x\":0,\"y\":0,\"properties\":{\"markdown\":\"# This is my dashboard\"}},{\"type\":\"text\",\"width\":6,\"height\":2,\"x\":6,\"y\":0,\"properties\":{\"markdown\":\"you like?\"}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":0,\"y\":2,\"properties\":{\"view\":\"timeSeries\",\"title\":\"Messages in queue\",\"region\":\"${ref0}\",\"annotations\":{\"alarms\":[\"${ref1}\"]},\"yAxis\":{\"left\":{\"min\":0}}}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":0,\"y\":8,\"properties\":{\"view\":\"timeSeries\",\"title\":\"More messages in queue with alarm annotation\",\"region\":\"${ref0}\",\"metrics\":[[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"${ref2}\",{\"yAxis\":\"left\",\"period\":300,\"stat\":\"Average\"}]],\"annotations\":{\"horizontal\":[{\"label\":\"ApproximateNumberOfMessagesVisible >= 100 for 3 datapoints within 15 minutes\",\"value\":100,\"yAxis\":\"left\"}]},\"yAxis\":{\"left\":{\"min\":0},\"right\":{\"min\":0}}}},{\"type\":\"metric\",\"width\":6,\"height\":3,\"x\":0,\"y\":14,\"properties\":{\"view\":\"singleValue\",\"title\":\"Current messages in queue\",\"region\":\"${ref0}\",\"metrics\":[[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"${ref2}\",{\"yAxis\":\"left\",\"period\":300,\"stat\":\"Average\"}]]}}]}",
-            {
-              "ref0": {
+          "Fn::Join": [
+            "",
+            [
+              "{\"widgets\":[{\"type\":\"text\",\"width\":6,\"height\":2,\"x\":0,\"y\":0,\"properties\":{\"markdown\":\"# This is my dashboard\"}},{\"type\":\"text\",\"width\":6,\"height\":2,\"x\":6,\"y\":0,\"properties\":{\"markdown\":\"you like?\"}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":0,\"y\":2,\"properties\":{\"view\":\"timeSeries\",\"title\":\"Messages in queue\",\"region\":\"",
+              {
                 "Ref": "AWS::Region"
               },
-              "ref1": {
+              "\",\"annotations\":{\"alarms\":[\"",
+              {
                 "Fn::GetAtt": [
                   "Alarm7103F465",
                   "Arn"
                 ]
               },
-              "ref2": {
+              "\"]},\"yAxis\":{\"left\":{\"min\":0}}}},{\"type\":\"metric\",\"width\":6,\"height\":6,\"x\":0,\"y\":8,\"properties\":{\"view\":\"timeSeries\",\"title\":\"More messages in queue with alarm annotation\",\"region\":\"",
+              {
+                "Ref": "AWS::Region"
+              },
+              "\",\"metrics\":[[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
+              {
                 "Fn::GetAtt": [
                   "queue",
                   "QueueName"
                 ]
-              }
-            }
+              },
+              "\",{\"yAxis\":\"left\",\"period\":300,\"stat\":\"Average\"}]],\"annotations\":{\"horizontal\":[{\"label\":\"ApproximateNumberOfMessagesVisible >= 100 for 3 datapoints within 15 minutes\",\"value\":100,\"yAxis\":\"left\"}]},\"yAxis\":{\"left\":{\"min\":0},\"right\":{\"min\":0}}}},{\"type\":\"metric\",\"width\":6,\"height\":3,\"x\":0,\"y\":14,\"properties\":{\"view\":\"singleValue\",\"title\":\"Current messages in queue\",\"region\":\"",
+              {
+                "Ref": "AWS::Region"
+              },
+              "\",\"metrics\":[[\"AWS/SQS\",\"ApproximateNumberOfMessagesVisible\",\"QueueName\",\"",
+              {
+                "Fn::GetAtt": [
+                  "queue",
+                  "QueueName"
+                ]
+              },
+              "\",{\"yAxis\":\"left\",\"period\":300,\"stat\":\"Average\"}]]}}]}"
+            ]
           ]
-        }
+        },
+        "DashboardName": "aws-cdk-cloudwatch-DashCCD7F836"
       }
     }
   }
-}
+}
diff --git a/packages/@aws-cdk/aws-cloudwatch/test/test.dashboard.ts b/packages/@aws-cdk/aws-cloudwatch/test/test.dashboard.ts
@@ -70,7 +70,7 @@ export = {
         test.done();
     },
 
-    'tokens in widgets are retained through FnSub'(test: Test) {
+    'tokens in widgets are retained'(test: Test) {
         // GIVEN
         const stack = new Stack();
         const dashboard = new Dashboard(stack, 'Dash');
@@ -82,14 +82,11 @@ export = {
 
         // THEN
         expect(stack).to(haveResource('AWS::CloudWatch::Dashboard', {
-            DashboardBody: { "Fn::Sub": [
-                // tslint:disable-next-line:max-line-length
-                "{\"widgets\":[{\"type\":\"metric\",\"width\":1,\"height\":1,\"x\":0,\"y\":0,\"properties\":{\"view\":\"timeSeries\",\"region\":\"${ref0}\",\"metrics\":[],\"annotations\":{\"horizontal\":[]},\"yAxis\":{\"left\":{\"min\":0},\"right\":{\"min\":0}}}}]}",
-                {
-                  ref0: { Ref: "AWS::Region" }
-                }
-              ]
-            }
+            DashboardBody: { "Fn::Join": [ "", [
+                "{\"widgets\":[{\"type\":\"metric\",\"width\":1,\"height\":1,\"x\":0,\"y\":0,\"properties\":{\"view\":\"timeSeries\",\"region\":\"",
+                { Ref: "AWS::Region" },
+                "\",\"metrics\":[],\"annotations\":{\"horizontal\":[]},\"yAxis\":{\"left\":{\"min\":0},\"right\":{\"min\":0}}}}]}"
+            ]]}
         }));
 
         test.done();

diff --git a/packages/@aws-cdk/aws-codebuild/test/integ.project-bucket.expected.json b/packages/@aws-cdk/aws-codebuild/test/integ.project-bucket.expected.json
@@ -86,16 +86,9 @@
                       ":",
                       "log-group",
                       ":",
+                      "/aws/codebuild/",
                       {
-                        "Fn::Join": [
-                          "",
-                          [
-                            "/aws/codebuild/",
-                            {
-                              "Ref": "MyProject39F7B0AE"
-                            }
-                          ]
-                        ]
+                        "Ref": "MyProject39F7B0AE"
                       }
                     ]
                   ]
@@ -126,16 +119,9 @@
                             ":",
                             "log-group",
                             ":",
+                            "/aws/codebuild/",
                             {
-                              "Fn::Join": [
-                                "",
-                                [
-                                  "/aws/codebuild/",
-                                  {
-                                    "Ref": "MyProject39F7B0AE"
-                                  }
-                                ]
-                              ]
+                              "Ref": "MyProject39F7B0AE"
                             }
                           ]
                         ]
@@ -160,8 +146,22 @@
     "MyProject39F7B0AE": {
       "Type": "AWS::CodeBuild::Project",
       "Properties": {
+        "Artifacts": {
+          "Type": "NO_ARTIFACTS"
+        },
+        "Environment": {
+          "ComputeType": "BUILD_GENERAL1_LARGE",
+          "Image": "aws/codebuild/ubuntu-base:14.04",
+          "PrivilegedMode": false,
+          "Type": "LINUX_CONTAINER"
+        },
+        "ServiceRole": {
+          "Fn::GetAtt": [
+            "MyProjectRole9BBE5233",
+            "Arn"
+          ]
+        },
         "Source": {
-          "Type": "S3",
           "Location": {
             "Fn::Join": [
               "",
@@ -173,22 +173,8 @@
                 "path/to/my/source.zip"
               ]
             ]
-          }
-        },
-        "Artifacts": {
-          "Type": "NO_ARTIFACTS"
-        },
-        "ServiceRole": {
-          "Fn::GetAtt": [
-            "MyProjectRole9BBE5233",
-            "Arn"
-          ]
-        },
-        "Environment": {
-          "Type": "LINUX_CONTAINER",
-          "PrivilegedMode": false,
-          "Image": "aws/codebuild/ubuntu-base:14.04",
-          "ComputeType": "BUILD_GENERAL1_LARGE"
+          },
+          "Type": "S3"
         }
       }
     }

diff --git a/packages/@aws-cdk/aws-codebuild/test/integ.project-events.expected.json b/packages/@aws-cdk/aws-codebuild/test/integ.project-events.expected.json
@@ -129,16 +129,9 @@
                       ":",
                       "log-group",
                       ":",
+                      "/aws/codebuild/",
                       {
-                        "Fn::Join": [
-                          "",
-                          [
-                            "/aws/codebuild/",
-                            {
-                              "Ref": "MyProject39F7B0AE"
-                            }
-                          ]
-                        ]
+                        "Ref": "MyProject39F7B0AE"
                       }
                     ]
                   ]
@@ -169,16 +162,9 @@
                             ":",
                             "log-group",
                             ":",
+                            "/aws/codebuild/",
                             {
-                              "Fn::Join": [
-                                "",
-                                [
-                                  "/aws/codebuild/",
-                                  {
-                                    "Ref": "MyProject39F7B0AE"
-                                  }
-                                ]
-                              ]
+                              "Ref": "MyProject39F7B0AE"
                             }
                           ]
                         ]
@@ -203,29 +189,29 @@
     "MyProject39F7B0AE": {
       "Type": "AWS::CodeBuild::Project",
       "Properties": {
-        "Source": {
-          "Type": "CODECOMMIT",
-          "Location": {
-            "Fn::GetAtt": [
-              "MyRepoF4F48043",
-              "CloneUrlHttp"
-            ]
-          }
-        },
         "Artifacts": {
           "Type": "NO_ARTIFACTS"
         },
+        "Environment": {
+          "ComputeType": "BUILD_GENERAL1_SMALL",
+          "Image": "aws/codebuild/ubuntu-base:14.04",
+          "PrivilegedMode": false,
+          "Type": "LINUX_CONTAINER"
+        },
         "ServiceRole": {
           "Fn::GetAtt": [
             "MyProjectRole9BBE5233",
             "Arn"
           ]
         },
-        "Environment": {
-          "Type": "LINUX_CONTAINER",
-          "PrivilegedMode": false,
-          "Image": "aws/codebuild/ubuntu-base:14.04",
-          "ComputeType": "BUILD_GENERAL1_SMALL"
+        "Source": {
+          "Location": {
+            "Fn::GetAtt": [
+              "MyRepoF4F48043",
+              "CloneUrlHttp"
+            ]
+          },
+          "Type": "CODECOMMIT"
         }
       }
     },