feature: Add ability to specify IAM role

README.md

@@ -72,7 +72,9 @@ Note that the ok and lastUpdated are reserved and will automatically be populate
 o ok is true when statuscode is 200, false otherwise
 o lastUpdated is the date.time at which the check was ran
 
-* healthcheck to be able to `invoke` lambdas requires the following Policy Statement in `iamRoleStatements`:
+* healthcheck needs to be able to `invoke` lambdas
+
+If your project relies on the IAM Role created by the Serverless Framework, you add the following Policy Statement in `iamRoleStatements`:
 
 ```yaml
 iamRoleStatements:
@@ -88,6 +90,8 @@ iamRoleStatements:
         - function:${self:service}-${opt:stage, self:provider.stage}-*
 ```
 
+Alternatively, you may specify the IAM Role explicitly, which will need to allow lambda invocation (`lambda:InvokeFunction`).  See options.
+
 If using pre-check, the deployment user also needs a similar policy so it can run the healthcheck lambda.
 
 * All done! healthcheck will run on SLS `deploy` and `package` commands
@@ -96,6 +100,7 @@ If using pre-check, the deployment user also needs a similar policy so it can ru
 
 * **cleanFolder** (default `true`)
 * **memorySize** (default `128`)
+* **role** (default `undefined` – if undefined, falls back to default IAM Role generated by Serverless Framework)
 * **name** (default `${service}-${stage}-healthcheck-plugin`)
 * **schedule** (default `rate(5 minutes)`)
 * **timeout** (default `10` seconds)
@@ -105,8 +110,9 @@ If using pre-check, the deployment user also needs a similar policy so it can ru
 ```yml
 custom:
   healthcheck:
-    cleanFolder: false,
+    cleanFolder: false
     memorySize: 256
+    role: healthCheckHandlerRole
     name: 'make-them-pop'
     schedule: 'rate(15 minutes)'
     timeout: 20

src/index.js

@@ -48,6 +48,7 @@ class HealthCheck {
     this.healthcheck = {
       cleanFolder: true,
       memorySize: 128,
+      role: undefined,
       name: this.serverless.service.service + '-' + this.options.stage + '-healthcheck-plugin',
       schedule: ['rate(5 minutes)'],
       timeout: 10,
@@ -70,6 +71,11 @@ class HealthCheck {
       this.healthcheck.memorySize = this.custom.healthcheck.memorySize
     }
 
+    /** Role */
+    if (typeof this.custom.healthcheck.role === 'string') {
+      this.healthcheck.role = this.custom.healthcheck.role
+    }
+
     /** Function name */
     if (typeof this.custom.healthcheck.name === 'string') {
       this.healthcheck.name = this.custom.healthcheck.name
@@ -211,6 +217,12 @@ class HealthCheck {
       timeout: this.healthcheck.timeout
     }
 
+    if (typeof this.healthcheck.role === 'string') {
+      this.serverless.service.functions.healthCheckPlugin.role = {
+        'Fn::GetAtt': [ this.healthcheck.role, 'Arn' ]
+      }
+    }
+
     return this.serverless.service.functions.healthCheckPlugin
   }