CAE Usage Process

Cloud Application Engine (CAE) is a serverless PaaS platform that provides simplified hosting for applications. It helps users migrate microservice applications to the cloud without O&M IaaS on a pay-per-use basis, effectively reducing costs and improving efficiency.

With CAE, applications can be deployed within minutes using source code, software packages, or container images. CAE supports mainstream languages such as Java, Node.js, and Tomcat and multiple runtime systems. It provides seamless hosting of multiple types of applications, including web applications, microservices, and APIs. Also, it supports auto scaling based on resources or custom service metrics to cope with unexpected user access traffic. Resources are billed by pay-per-use. In addition, CAE provides pluggable runtimes for you to focus on application development. Built-in application governance enable self-healing and quick recovery of cloud native applications.

Before using CAE, study this section to grasp how the service works.

Figure 1 CAE usage process
Click to enlarge

Constraints

Federated users cannot use CAE.

Prerequisites

When you log in to the CAE console for the first time using an administrator account, you need to grant the CAE trust policies, ServiceStage Developer, SFS3 FullAccess, OBS Administrator, and CAEAgencyPolicy permissions to CAE to ensure that the subsequent functions can be used properly. Authorization method:
When you log in to the CAE console for the first time using an administrator account, click the authorization button in the service authorization dialog box. Then, CAE creates an agency named cae_trust for you in IAM. To ensure normal service usage, do not delete or modify cae_trust when using CAE. The permissions are as follows:
- CAE trust policies: Permission required when the CAE environment is used, events are reported, and the component access mode is set to external ELB.
- ServiceStage Developer: ServiceStage developer, who has full permissions for this service but does not have the permission for creating infrastructure.
- SFS3 FullAccess: Default read and write permissions for the general file system.
- OBS Administrator: Administrator permissions for OBS.
- CAEAgencyPolicy: Custom policy of CAE, which is used to control IAM users' access to CAE.

Authorizing a User to Use CAE

Register a Huawei ID and enable Huawei Cloud services. An account is created after you sign up for Huawei Cloud. Your account has full access permissions for your resources and makes payments for the use of these resources. For security purposes, create one or more IAM users.

Creating a User and Granting Permissions: New IAM users do not have any permissions assigned by default. You need to first add them to one or more groups and then attach policies or roles to these groups. The users then inherit permissions from the groups and can perform specified operations on cloud services based on the permissions they have been assigned. For details about all system permissions of CAE, see Permissions Management.

Creating a Custom CAE Policy: Custom policies supplement the system-defined policies of CAE.

Log in to CAE: If you log in for the first time, click OK in the service authorization dialog box to authorize CAE to use dependent services. CAE will create an agency named cae_trust in IAM before you access the CAE console. If this is not your first login, the CAE console is displayed directly.

Creating an Environment Using CAE

Creating an Environment: Environments distinguish service deployment scenarios and means isolation. You can create application components in different environments to isolate them.

Creating an Application Using CAE

Creating an Application: An application is a service system with functions and consists of one or more application components. You can create applications and components under an application to provide services externally.

Creating a Component Using CAE

Creating a Component: An application component implements a service feature of an application. It is in the form of code or software packages and can be deployed independently. You can deploy components in the current environment and application by deploying code sources, software packages, or image packages.

Deploying code sources: Use open-source code repositories or Huawei Cloud services, such as CodeArts, GitHub, and GitCode, to upload code to code repositories.
Deploying software packages: Upload a software package to the software release repository using CodeArts, upload a software package to an OBS bucket using Object Storage Service (OBS), or upload a software package to a repository using GitHub artifact.
Deploying an image package: Upload an image package to an image repository using SoftWare Repository for Container (SWR).

Configuring a CAE Component

Component Configurations: After a component is deployed, you can configure RDS for data interaction and CSE for microservice management and governance, and configure environment variables, access modes, AS policies, cloud storage mounting, health check, lifecycle, log collection, performance management, and custom metrics for components.

CAE Console Overview

Table 1 describes the CAE console.

**Table 1** CAE console description
Item	Description
Overview	Provides overall CAE dashboard information, including the application health status, CPU usage, memory usage, traffic, network inbound speeds, basic environment information, and network information.
Components	Provides capabilities such as creating, deploying, and upgrading components. A component is a self-owned package or public middleware that can be deployed and provides services externally.
Instance List	Allows you to view instance information, delete instances, and log in to containers using CloudShell.
Component Configurations	Provides component-based middleware configuration and O&M management for RDS databases, CSE engines, environment variables, access modes, AS policies, cloud storage configuration, health check, lifecycle, log collection, performance management, and custom monitoring metrics.
Component Events	Displays events that occur during component deployment and running.
Component Monitoring	Provides component monitoring, including visualized real-time monitoring of uplink and downlink speeds (BPS), uplink and downlink rates (PPS), file system write/read rate, CPU usage, and memory usage.
Component Logs	Provides instance-level running logs to help locate faults.
URL Monitoring	After URL log monitoring is enabled, CAE reports URL routing logs to LTS. You can monitor URL logs of application components using LTS.
System Settings	You can configure environments and global settings, including cloud storage authorization, domain name configuration, certificate configuration, start/stop policy configuration, system network configuration, monitoring system configuration, compute resource pool configuration, source code repository authorization, event notification rules, and credential configuration.