"The role defined for the function cannot be assumed by Lambda" error after upgrading to 1.55.0

[jg-synth]

Bug Report

Description

1. What did you do?

   I upgraded to serverless@1.55.0 and deployed the latest version of an existing application. Note that this was a re-release (i.e. the same version had been released previously using serverless@1.54.0).

   $ yarn global add serverless@1.55.0
   $ serverless deploy --stage dev
   

2. What happened?

   Whilst the CloudFormation stack updates, the following error occurs.

   The role defined for the function cannot be assumed by Lambda. (Service: AWSLambdaInternal; Status Code: 400; Error Code: InvalidParameterValueException; Request ID: b63d4eb3-3e38-4d75-a90d-2b23ec1b9606)
   

3. What should've happened?

   The deployment should have completed successfully.

4. What's the content of your serverless.yml file?

   app: enact-services
   custom:
   wsgi:
       app: main.app
       packRequirements: false
   pythonRequirements:
       dockerizePip: non-linux
   functions:
   api:
       events:
       - http:
           cors: true
           method: ANY
           path: / # The base path.
       - http:
           cors: true
           method: ANY
           path: /{any+} # All other paths.
       handler: wsgi_handler.handler
   org: <redacted>
   plugins:
   - serverless-python-requirements
   - serverless-wsgi
   provider:
   cfnRole: arn:aws:iam::<redacted>:role/ServerlessCloudFormation
   iamRoleStatements: <redacted>  
   name: aws
   region: eu-west-1
   runtime: python3.7
   service: python-rest-api
   

5. What's the output you get when you use the SLS_DEBUG=* environment variable (e.g. SLS_DEBUG=* serverless deploy)

    Serverless: Load command config
    Serverless: Load command config:credentials
    Serverless: Load command config:tabcompletion
    Serverless: Load command config:tabcompletion:install
    Serverless: Load command config:tabcompletion:uninstall
    Serverless: Load command create
    Serverless: Load command install
    Serverless: Load command package
    Serverless: Load command deploy
    Serverless: Load command deploy:function
    Serverless: Load command deploy:list
    Serverless: Load command deploy:list:functions
    Serverless: Load command invoke
    Serverless: Load command invoke:local
    Serverless: Load command info
    Serverless: Load command logs
    Serverless: Load command metrics
    Serverless: Load command print
    Serverless: Load command remove
    Serverless: Load command rollback
    Serverless: Load command rollback:function
    Serverless: Load command slstats
    Serverless: Load command plugin
    Serverless: Load command plugin
    Serverless: Load command plugin:install
    Serverless: Load command plugin
    Serverless: Load command plugin:uninstall
    Serverless: Load command plugin
    Serverless: Load command plugin:list
    Serverless: Load command plugin
    Serverless: Load command plugin:search
    Serverless: Load command config
    Serverless: Load command config:credentials
    Serverless: Load command rollback
    Serverless: Load command rollback:function
    Serverless: Load command requirements
    Serverless: Load command requirements:clean
    Serverless: Load command requirements:install
    Serverless: Load command requirements:cleanCache
    Serverless: Load command wsgi
    Serverless: Load command wsgi:serve
    Serverless: Load command wsgi:install
    Serverless: Load command wsgi:clean
    Serverless: Load command wsgi:command
    Serverless: Load command wsgi:command:local
    Serverless: Load command wsgi:exec
    Serverless: Load command wsgi:exec:local
    Serverless: Load command wsgi:manage
    Serverless: Load command wsgi:manage:local
    Serverless: Load command wsgi:flask
    Serverless: Load command wsgi:flask:local
    Serverless: Load command login
    Serverless: Load command logout
    Serverless: Load command generate-event
    Serverless: Load command test
    Serverless: Load command dashboard
    platform-sdk fetching: POST https://api.serverless.com/core/tenants/jdgillespie91/applications/enact-services/profileValue
    Serverless: Invoke deploy
    Serverless: Invoke package
    Serverless: Invoke aws:common:validate
    Serverless: Invoke aws:common:cleanupTempDir
    Serverless: Generated requirements from /home/jake/workspace/<redacted>/services/python-rest-api/requirements.txt in /home/jake/workspace/<redacted>/services/python-rest-api/.serverless/requirements.txt...
    Serverless: Using static cache of requirements found at /home/jake/.cache/serverless-python-requirements/d9b5683b17a71dd984418857d31a4475179531d117e58b548328d556b240ba69_slspyc ...
    Serverless: Using Python specified in "runtime": python3.7
    Serverless: Packaging Python WSGI handler...
    platform-sdk fetching: GET https://api.serverless.com/core/tenants/jdgillespie91/applications/enact-services
    platform-sdk fetching: GET https://api.serverless.com/core/meta
    Serverless: Packaging service...
    Serverless: Excluding development dependencies...
    Serverless: Injecting required Python packages to package...
    Serverless: Installing dependencies for custom CloudFormation resources...
    Serverless: Invoke aws:package:finalize
    Serverless: [AWS sts 200 0.357s 0 retries] getCallerIdentity({})
    platform-sdk fetching: POST https://api.serverless.com/malt/destinations/create
    Serverless: Invoke aws:common:moveArtifactsToPackage
    Serverless: Invoke aws:common:validate
    Serverless: Safeguards Processing...
    Serverless: Safeguards Results:
   
    Summary --------------------------------------------------
   
    running - allowed-runtimes
    passed - allowed-runtimes
    running - allowed-regions
    passed - allowed-regions
    running - no-secret-env-vars
    passed - no-secret-env-vars
    running - require-cfn-role
    passed - require-cfn-role
    running - framework-version
    passed - framework-version
    running - no-unsafe-wildcard-iam-permissions
    passed - no-unsafe-wildcard-iam-permissions
    running - allowed-stages
    passed - allowed-stages
   
    Serverless: Safeguards Summary: 7 passed, 0 warnings, 0 errors
    Serverless: Invoke aws:deploy:deploy
    Serverless: [AWS cloudformation 200 0.122s 0 retries] describeStacks({ StackName: 'python-rest-api-dev' })
    Serverless: [AWS cloudformation 200 0.099s 0 retries] describeStackResource({ StackName: 'python-rest-api-dev',
    LogicalResourceId: 'ServerlessDeploymentBucket' })
    Serverless: [AWS s3 200 0.148s 0 retries] listObjectsV2({ Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Prefix: 'serverless/python-rest-api/dev' })
    Serverless: [AWS s3 200 0.086s 0 retries] headObject({ Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571844466535-2019-10-23T15:27:46.535Z/custom-resources.zip' })
    Serverless: [AWS s3 200 0.098s 0 retries] headObject({ Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571844466535-2019-10-23T15:27:46.535Z/python-rest-api.zip' })
    Serverless: [AWS s3 200 0.077s 0 retries] headObject({ Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571844466535-2019-10-23T15:27:46.535Z/compiled-cloudformation-template.json' })
    Serverless: [AWS lambda 200 0.127s 0 retries] getFunction({ FunctionName: 'python-rest-api-dev-api' })
    Serverless: [AWS sts 200 0.345s 0 retries] getCallerIdentity({})
    Serverless: Uploading CloudFormation file to S3...
    Serverless: [AWS s3 200 0.236s 0 retries] putObject({ Body:
    <Buffer 7b 22 41 57 53 54 65 6d 70 6c 61 74 65 46 6f 72 6d 61 74 56 65 72 73 69 6f 6e 22 3a 22 32 30 31 30 2d 30 39 2d 30 39 22 2c 22 44 65 73 63 72 69 70 74 ... >,
    Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571845455510-2019-10-23T15:44:15.510Z/compiled-cloudformation-template.json',
    ContentType: 'application/json',
    Metadata:
    { filesha256: '14H2rR59C3ZaTCSFhRhavT7ZFxAFRjXKyqCS/OTayFI=' } })
    Serverless: Uploading artifacts...
    Serverless: Uploading service python-rest-api.zip file to S3 (57.04 MB)...
    Serverless: [AWS s3 200 0.116s 0 retries] createMultipartUpload({ Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571845455510-2019-10-23T15:44:15.510Z/python-rest-api.zip',
    ContentType: 'application/zip',
    Metadata:
    { filesha256: 'vbki9d4ggYLpOp0ODl8f+UY6S2xFEu8kGU8gyKzHy7A=' } })
    Serverless: [AWS s3 200 1.993s 0 retries] uploadPart({ Body:
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    ContentLength: 5242880,
    PartNumber: 2,
    Bucket:
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    Key:
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    UploadId:
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    Serverless: [AWS s3 200 2.001s 0 retries] uploadPart({ Body:
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    ContentLength: 5242880,
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    UploadId:
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    Serverless: [AWS s3 200 2.105s 0 retries] uploadPart({ Body:
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    ContentLength: 5242880,
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    UploadId:
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    Serverless: [AWS s3 200 2.192s 0 retries] uploadPart({ Body:
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    Serverless: [AWS s3 200 1.678s 0 retries] uploadPart({ Body:
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    UploadId:
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    Serverless: [AWS s3 200 2.001s 0 retries] uploadPart({ Body:
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    Serverless: [AWS s3 200 2.066s 0 retries] uploadPart({ Body:
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    Serverless: [AWS s3 200 1.046s 0 retries] uploadPart({ Body:
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    Serverless: [AWS s3 200 0.143s 0 retries] completeMultipartUpload({ MultipartUpload:
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    Serverless: Uploading custom CloudFormation resources...
    Serverless: [AWS s3 200 0.12s 0 retries] createMultipartUpload({ Bucket:
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    Metadata:
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    Bucket:
    'python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb',
    Key:
    'serverless/python-rest-api/dev/1571845455510-2019-10-23T15:44:15.510Z/custom-resources.zip',
    UploadId:
    'XTRJRadNxPm7yUsZfOK5DPrpPzesgKlfQO7Tw_DZHAwOrhYXAX471DPvtgcbaG5Wo8SNFftmQpaE70nZbGQMY6ZsXFM0S4NIdRY_3lLbj5v7zYL8aZK9LlIq5m0dXGLK' })
    Serverless: Validating template...
    Serverless: [AWS cloudformation 200 0.373s 0 retries] validateTemplate({ TemplateURL:
    'https://s3.amazonaws.com/python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb/serverless/python-rest-api/dev/1571845455510-2019-10-23T15:44:15.510Z/compiled-cloudformation-template.json' })
    Serverless: Updating Stack...
    Serverless: [AWS cloudformation 200 0.415s 0 retries] updateStack({ StackName: 'python-rest-api-dev',
    Capabilities: [ 'CAPABILITY_IAM', 'CAPABILITY_NAMED_IAM', [length]: 2 ],
    Parameters: [ [length]: 0 ],
    TemplateURL:
    'https://s3.amazonaws.com/python-rest-api-dev-serverlessdeploymentbucket-1skkoq13ljotb/serverless/python-rest-api/dev/1571845455510-2019-10-23T15:44:15.510Z/compiled-cloudformation-template.json',
    Tags: [ { Key: 'STAGE', Value: 'dev' }, [length]: 1 ],
    RoleARN: 'arn:aws:iam::<redacted>:role/ServerlessCloudFormation' })
    Serverless: Checking Stack update progress...
    Serverless: [AWS cloudformation 200 0.222s 0 retries] describeStackEvents({ StackName:
    'arn:aws:cloudformation:eu-west-1:<redacted>:stack/python-rest-api-dev/f1c3db20-ea87-11e9-b3b3-0ade9df0c35e' })
    ....
    Serverless: Operation failed!
    Serverless: View the full error output: https://eu-west-1.console.aws.amazon.com/cloudformation/home?region=eu-west-1#/stack/detail?stackId=arn%3Aaws%3Acloudformation%3Aeu-west-1%3A<redacted>%3Astack%2Fpython-rest-api-dev%2Ff1c3db20-ea87-11e9-b3b3-0ade9df0c35e
    Serverless: Publishing service to the Serverless Dashboard...
    Serverless: [AWS sts 200 0.362s 0 retries] getCallerIdentity({})
    Serverless: [AWS cloudformation 200 0.103s 0 retries] describeStacks({ StackName: 'python-rest-api-dev' })
    platform-sdk fetching: POST https://api.serverless.com/core/tenants/jdgillespie91/applications/enact-services/services/python-rest-api/stages/dev/regions/eu-west-1/deployments
    Serverless: Successfully published your service to the Serverless Dashboard: https://dashboard.serverless.com/tenants/jdgillespie91/applications/enact-services/services/python-rest-api/stage/dev/region/eu-west-1
    
    Serverless Error ---------------------------------------
    
    ServerlessError: An error occurred: CustomDashresourceDashapigwDashcwDashroleLambdaFunction - The role defined for the function cannot be assumed by Lambda. (Service: AWSLambdaInternal; Status Code: 400; Error Code: InvalidParameterValueException; Request ID: f3603229-2ffd-4f7f-b441-e3153321cf75).
        at provider.request.then.data (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/monitorStack.js:122:33)
    From previous event:
        at AwsDeploy.monitorStack (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/monitorStack.js:28:12)
        at provider.request.then.cfData (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/updateStack.js:103:28)
    From previous event:
        at AwsDeploy.update (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/updateStack.js:103:8)
    From previous event:
        at AwsDeploy.BbPromise.bind.then (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/updateStack.js:117:35)
    From previous event:
        at AwsDeploy.updateStack (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/lib/updateStack.js:113:33)
    From previous event:
        at AwsDeploy.BbPromise.bind.then (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/deploy/index.js:127:39)
    From previous event:
        at Object.aws:deploy:deploy:updateStack [as hook] (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/deploy/index.js:123:30)
        at BbPromise.reduce (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:489:55)
    From previous event:
        at PluginManager.invoke (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:489:22)
        at PluginManager.spawn (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:509:17)
        at AwsDeploy.BbPromise.bind.then (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/deploy/index.js:93:48)
    From previous event:
        at Object.deploy:deploy [as hook] (/home/jake/.config/yarn/global/node_modules/serverless/lib/plugins/aws/deploy/index.js:89:30)
        at BbPromise.reduce (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:489:55)
    From previous event:
        at PluginManager.invoke (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:489:22)
        at getHooks.reduce.then (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:524:24)
    From previous event:
        at PluginManager.run (/home/jake/.config/yarn/global/node_modules/serverless/lib/classes/PluginManager.js:524:8)
        at variables.populateService.then (/home/jake/.config/yarn/global/node_modules/serverless/lib/Serverless.js:115:33)
        at runCallback (timers.js:705:18)
        at tryOnImmediate (timers.js:676:5)
        at processImmediate (timers.js:658:5)
        at process.topLevelDomainCallback (domain.js:126:23)
    From previous event:
        at Serverless.run (/home/jake/.config/yarn/global/node_modules/serverless/lib/Serverless.js:102:74)
        at serverless.init.then (/home/jake/.config/yarn/global/node_modules/serverless/bin/serverless.js:72:30)
        at /home/jake/.config/yarn/global/node_modules/serverless/node_modules/fs-extra/node_modules/graceful-fs/graceful-fs.js:136:16
        at /home/jake/.config/yarn/global/node_modules/serverless/node_modules/graceful-fs/graceful-fs.js:111:16
        at /home/jake/.config/yarn/global/node_modules/graceful-fs/graceful-fs.js:57:14
        at /home/jake/.config/yarn/global/node_modules/serverless/node_modules/graceful-fs/graceful-fs.js:45:10
        at FSReqWrap.args [as oncomplete] (fs.js:140:20)
    From previous event:
        at initializeErrorReporter.then (/home/jake/.config/yarn/global/node_modules/serverless/bin/serverless.js:72:8)
        at runCallback (timers.js:705:18)
        at tryOnImmediate (timers.js:676:5)
        at processImmediate (timers.js:658:5)
        at process.topLevelDomainCallback (domain.js:126:23)
    From previous event:
        at Object.<anonymous> (/home/jake/.config/yarn/global/node_modules/serverless/bin/serverless.js:61:4)
        at Module._compile (internal/modules/cjs/loader.js:778:30)
        at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
        at Module.load (internal/modules/cjs/loader.js:653:32)
        at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
        at Function.Module._load (internal/modules/cjs/loader.js:585:3)
        at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
        at startup (internal/bootstrap/node.js:283:19)
        at bootstrapNodeJSCore (internal/bootstrap/node.js:622:3)
    
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    Your Environment Information ---------------------------
        Operating System:          linux
        Node Version:              10.16.3
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        Components CLI Version:    1.4.0
   

[medikoo]

@jg-synth great thanks for report. It's due to this change #6871 Logically it makes sense, although I understand it can also be seen as breaking.

In your case, to recover, you need to ensure that role you provide withcfnRole setting has "lambda.amazonaws.com" listed as one of the trusted principal services, and that it provides necessary rights for custom resources lambdas which setup the needed resources (custom resource lambda covers setup which cannot be done by CloudFormation directly).

[jg-synth]

@medikoo Thanks for getting back, and I can confirm that adding "lambda.amazonaws.com" to the cfnRole I'm using worked a treat.

Great work, and much appreciated.