AWS Step Functions Workshop - Code Snippets

01_StateMachineDefinition.json

{
  "StartAt": "Create User",
  "States": {
    "Create User": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME",
      "Next": "Assign Roles"
    }, 
    "Assign Roles": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME",
      "Next": "Set Permissions"
    },
    "Set Permissions": {
      "Type": "Choice",
      "Choices": [
        {
          "Variable": "$.Role",
          "StringEquals": "Admin",
          "Next": "Grant Admin Permissions"
        },
        {
          "Variable": "$.Role",
          "StringEquals": "User",
          "Next": "Grant User Permissions"
        }
      ]
    },
    "Grant Admin Permissions": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME",
      "Next": "Grant User Permissions"
    },
    "Grant User Permissions": {
      "Type": "Task",
      "Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME",
      "End": true
    }
  }
}

02_CreateUser_Function.js

exports.handler = (event, context, callback) => {
  var result = {
    UserName: event.UserName,
    Role: event.Role,
    Message: "User " + event.UserName + ": created..."
  };
  callback(null, result);
};

03_AssignRoles_Function.js

exports.handler = (event, context, callback) => {
  var result = {
    UserName: event.UserName,
    Role: event.Role,
    Message: "User " + event.UserName + ": given role " + event.Role + "..."
  };
  callback(null, result);
};

04_GrantAdminPermissions_Function.js

exports.handler = (event, context, callback) => {
  var permissions = event.Permissions || [];
  permissions.push("Manage Users");
  
  var result = {
    UserName: event.UserName,
    Role: event.Role,
    Permissions: permissions
  };
  callback(null, result);
};

05_GrantUserPermissions_Function.js

exports.handler = (event, context, callback) => {
  var permissions = event.Permissions || [];
  permissions.push("View Users");
  
  var result = {
    UserName: event.UserName,
    Role: event.Role,
    Permissions: permissions
  };
  callback(null, result);
};

06_SampleInput.json

{
  "UserName": "Tom Waits",
  "Role": "Admin"
}