General fixes and new kms support

src/kms/kms.service.ts

@@ -0,0 +1,22 @@
+import { Injectable } from '@nestjs/common';
+import { ArnParts } from '../util/breakdown-arn';
+import { InjectRepository } from '@nestjs/typeorm';
+import { KmsKeyAlias } from './kms-key-alias.entity';
+import { Repository } from 'typeorm';
+
+@Injectable()
+export class KmsService {
+  constructor(
+    @InjectRepository(KmsKeyAlias)
+    private readonly aliasRepo: Repository<KmsKeyAlias>,
+  ) {}
+
+  async findKeyIdFromAlias(alias: string, arn: ArnParts): Promise<string> {
+    const record = await this.aliasRepo.findOne({ where: { 
+      name: alias, 
+      accountId: arn.accountId,
+      region: arn.region,
+    }});
+    return record.targetKeyId;
+  }
+}