serverless/lib/plugins/awsCompileFunctionsToResources/awsCompileFunctionsToResources.js

'use strict';

const BbPromise = require('bluebird');
const forEach = require('lodash').forEach;
const merge = require('lodash').merge;

class AwsCompileFunctionsToResources {
  constructor(serverless) {
    this.serverless = serverless;

    // TODO pass in the right stage and region
    this.stage = 'dev';
    this.region = 'aws_useast1';

    // default properties
    this.functions = []; // extracted functions from the serverless.yaml file as JS objects
    this.functionResources = []; // AWS resource definitions for the functions
    this.cloudFormationResult = {};

    // TODO: remove because it relies on awsResourcesDeploy hooks
    this.commands = {
      compile: {
        commands: {
          functions: {
            usage: 'Compiles the function definition in serverless.yaml to a CloudFormation stack',
            lifecycleEvents: [
              'compile',
            ],
          },
        },
      },
    };

    this.hooks = {
      'compile:functions:compile': (options) => {
        this.options = options;
        return BbPromise.bind(this)
          .then(this.extractFunctions)
          .then(this.createFunctionResources)
          .then(this.addFunctionResourcesToCFMainTemplate)
          .catch((exception) => {
            throw new this.serverless.classes.Error(exception);
          });
      },
    };
  }

  extractFunctions() {
    const functions = this.serverless.service.functions;

    forEach(functions, (value, key) => {
      // check if it's the function and not the name_template property
      if (key !== 'name_template') {
        const functionObject = {
          [key]: value,
        };

        this.functions.push(functionObject);
      }
    });
    return BbPromise.resolve();
  }

  createFunctionResources() {
    const functionTemplate = `
      {
        "Type": "AWS::Lambda::Function",
        "Properties": {
        "Code": "Code",
        "FunctionName": "FunctionName",
          "Handler": "Handler",
          "MemorySize": "MemorySize",
          "Role": "Role",
          "Runtime": "Runtime",
          "Timeout": "Timeout"
        }
      }
    `;

    this.functions.forEach((func) => {
      const newFunction = JSON.parse(functionTemplate);
      const functionName = Object.keys(func)[0];

      const role = this.serverless.service.getVariables(this.stage, this.region).iamRoleArnLambda;

      if (!functionName) {
        throw new this.serverless.classes.Error('Please define a name for your function.');
      }

      if (!func[functionName].handler) {
        throw new this.serverless.classes.Error('Please define a handler for your function.');
      }

      if (!func[functionName].provider.aws_lambda.memorySize) {
        throw new this.serverless.classes.Error('Please define a memory size for your function.');
      }

      if (!role) {
        throw new this.serverless.classes.Error('Please define a IAM ARN role for your function.');
      }

      if (!func[functionName].provider.aws_lambda.runtime) {
        throw new this.serverless.classes.Error('Please define a runtime for your function.');
      }

      if (!func[functionName].provider.aws_lambda.timeout) {
        throw new this.serverless.classes.Error('Please define a timeout for your function.');
      }

      newFunction.Properties.Code = ''; // Code will be added later on!
      newFunction.Properties.FunctionName = functionName;
      newFunction.Properties.Handler = func[functionName].handler;
      newFunction.Properties.MemorySize = func[functionName].provider.aws_lambda.memorySize;
      newFunction.Properties.Role = role;
      newFunction.Properties.Runtime = func[functionName].provider.aws_lambda.runtime;
      newFunction.Properties.Timeout = func[functionName].provider.aws_lambda.timeout;

      const functionResourceKey = `${functionName}Lambda`;

      const newFunctionObject = {
        [functionResourceKey]: newFunction,
      };

      this.functionResources.push(newFunctionObject);
    });
    return BbPromise.resolve();
  }

  addFunctionResourcesToCFMainTemplate() {
    let CFMainTemplate = `
      {
        "AWSTemplateFormatVersion": "2010-09-09",
        "Description": "AWS CloudFormation template",
        "Resources": {
          "IamRoleLambda": {
            "Type": "AWS::IAM::Role",
            "Properties": {
              "AssumeRolePolicyDocument": {
                "Version": "2012-10-17",
                "Statement": [
                  {
                    "Effect": "Allow",
                    "Principal": {
                      "Service": [
                        "lambda.amazonaws.com"
                      ]
                    },
                    "Action": [
                      "sts:AssumeRole"
                    ]
                  }
                ]
              },
              "Path": "/"
            }
          },
          "IamPolicyLambda": {
            "Type": "AWS::IAM::Policy",
            "Properties": {
              "PolicyName": "stage-lambda",
              "PolicyDocument": {
                "Version": "2012-10-17",
                "Statement": [
                  {
                    "Effect": "Allow",
                    "Action": [
                      "logs:CreateLogGroup",
                      "logs:CreateLogStream",
                      "logs:PutLogEvents"
                    ],
                    "Resource": "arn:aws:logs:region:*:*"
                  }
                ]
              },
              "Roles": [
                {
                  "Ref": "IamRoleLambda"
                }
              ]
            }
          }
        },
        "Outputs": {
          "IamRoleArnLambda": {
            "Description": "ARN of the lambda IAM role",
            "Value": {
              "Fn::GetAtt": [
                "IamRoleLambda",
                "Arn"
              ]
            }
          }
        }
      }
    `;
    CFMainTemplate = JSON.parse(CFMainTemplate);

    // set the necessary variables before adding the function resources
    CFMainTemplate
      .Resources
      .IamPolicyLambda
      .Properties
      .PolicyName = `${this.stage}-lambda`;
    CFMainTemplate.Resources
      .IamPolicyLambda
      .Properties
      .PolicyDocument
      .Statement[0]
      .Resource = `arn:aws:logs:${this.region}:*:*`;

    this.functionResources.forEach((functionResource) => {
      merge(CFMainTemplate.Resources, functionResource);
    });

    this.cloudFormationResult = CFMainTemplate;

    // TODO pass the result to awsResourcesDeploy plugin
    console.log(JSON.stringify(this.cloudFormationResult, null, 2));

    return BbPromise.resolve();
  }
}

module.exports = AwsCompileFunctionsToResources;