:Server integration

Overview

This topic describes the integration of the Alibaba Cloud LongVideo AppServer. You can use this AppServer for many events such as data exchange between the LongVideo application and ApsaraVideo VOD, business logic processing, and data management. For example, you can randomly generate users, obtain video lists, obtain credential information, upload videos, and process various callback events. The technologies involved include the Spring Boot microservice framework, ApsaraDB RDS for MySQL, and MyBatis persistence framework.

Alibaba Cloud service activation

The following Alibaba Cloud services are required: Elastic Compute Service (ECS), ApsaraDB for RDS, and ApsaraVideo VOD.

ECS

ECS is a computing service that features auto scaling. It can help you reduce IT costs and improve O&M efficiency, so that you can concentrate on core business innovation. You can click Elastic Compute Service to activate the ECS service.

[alivcsdk@ilvb-app-server-1 ~]$ java -version
java version "1.8.0_191"
Java(TM) SE Runtime Environment (build 1.8.0_191-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.191-b12, mixed mode)

ApsaraDB for RDS

ApsaraDB for RDS is a database that is optimized or deployed in a virtual computing environment. It has advantages such as pay-as-you-go, on-demand scaling, high availability, and storage integration. This demo database only supports ApsaraDB RDS for MySQL. Ensure that your ApsaraDB for RDS instance resides in the same region as your ECS instance. You can click ApsaraDB RDS to activate the ApsaraDB for RDS service.

ApsaraVideo VOD

ApsaraVideo VOD is an all-in-one audio- and video-on-demand solution. It integrates video collection, editing, and uploading, media resource management, automatic transcoding (Narrowband HD™), video content moderation and analysis, and Content Delivery Network (CDN) for accelerated content delivery. You can click ApsaraVideo VOD to activate the ApsaraVideo VOD service.

Alibaba Cloud service configuration

ApsaraVideo VOD

ApsaraVideo VOD provides a variety of media processing capabilities. With economic, elastic, and highly scalable audio and video conversion methods, ApsaraVideo VOD helps you transcode your audio and videos to formats suitable for playback on PCs, TVs, and mobile devices. Based on the transcoding capability of ApsaraVideo VOD, LongVideo provides advanced capabilities such as secure watermark sharing, Narrowband HD, and AI media audit. To use LongVideo, you need to configure domain names, transcoding templates, and callback events.

1. Configure domain names.

To access videos or images in ApsaraVideo VOD, you need to configure at least a domain name. This domain name is also required when you configure projects.

1. Configure transcoding templates.

Considering user experience and security, you need to play videos without watermarks on an application or webpage, but add watermarks to downloaded videos and shared videos. We also recommend that you configure the same resolution for played videos and downloaded videos. You can implement these features by using the transcoding service of ApsaraVideo VOD. The configuration procedure is as follows: Log on to the ApsaraVideo VOD console. In the left-side navigation pane, choose Configuration Management > Media Processing > Transcode. On the Transcode page, click Create Template to create two transcoding templates and set Definition to Low Definition and Standard Definition, respectively, as follows:

• Low Definition: 720p without watermarks

• Standard Definition: 720p with watermarks

1. Configure callback events.

Video processing services such as AI media audit, video snapshot, and transcoding jobs are processed asynchronously. ApsaraVideo VOD notifies business parties of all the status updates and processing results by sending asynchronous messages or callback event notifications. The LongVideo demo uses HTTP requests as the callback method to send callback event notifications. The configuration procedure is as follows:Log on to the ApsaraVideo VOD console. In the left-side navigation pane, choose Configuration Management > Media Processing > Callback. On the Callback page, click Modify. In the Callback dialog box that appears, set parameters and select the following options for Events: All Transcoding Tasks Completed, AI Processing Completed, Create Audit Completed, and Screenshot Created.

1. Configure callback authentication.ApsaraVideo VOD allows you to add a specific signature header to each HTTP or HTTPS callback request. In this way, the server that receives callback event notifications can authenticate the signature to prevent illegal or invalid requests.First, configure callback authentication in the ApsaraVideo VOD console.Then, modify the code. Open the project file src/main/resources/application.properties and set the CALLBACK_PRIVETEKEY parameter to the private key set in the ApsaraVideo VOD console.

1. Configure the video audit feature.

The video audit feature allows you to audit videos before publishing them. You can block improper videos in a timely manner or in advance to reduce or avoid adverse effects caused by these videos when they are published.

ApsaraDB for RDS

1. Configure the whitelist for accessing ApsaraDB for RDS. For more information, see Configure a whitelist.

2. Create an ApsaraDB for RDS account.

This account is used to log on to the ApsaraDB for RDS database. Under this account, you can use code to create database connections, and log on to the ApsaraDB for RDS console to create tables and initialize databases. We recommend that you keep the username and password properly.

On the instance management page, click Accounts in the left-side navigation pane. On the Accounts page, click Create Account. On the page that appears, set parameters to create an account, including Database Account, Account Type, Password, and Re-enter Password.

1. Create a database.On the instance management page, click Databases in the left-side navigation pane. On the Database page, click Create Database in the upper-right corner. The Create Database page appears, as shown in the following figure.

Configure the following fields:Supported Character Set: the supported character set. Select utf8mb4 to support emoticons.Authorized Account: the account authorized by the database. Select an account authorized by this database.Account Type: the account permission. Select Read/Write to grant the required read and write permissions to the account.

1. Initialize the database. On the instance management page, click Basic Information in the left-side navigation pane. On the page that appears, click Log On to DB. The RDS Database Logon page appears, as shown in the following figure.

In the ApsaraDB for RDS console, click Log On to DB in the upper-right corner to go to the database logon page in the DMS console. Select the network address of the relevant instance and use the username and password of the previously created account to log on to the previously created database. Then, you can create tables and initialize data as follows:

• Create a table.Find the appserver_create_table.sql file in the sql directory in the root directory of your project. Use the table creation statements in the file to create tables.

Alibaba Cloud RAM

Resource Access Management (RAM) is an Alibaba Cloud service designed for user identity management and resource access control. You can use RAM to create and manage RAM users (such as employees, systems, or applications) and control their access permissions on resources under your Alibaba Cloud account. If multiple people in your enterprise work collaboratively and share resources, you do not have to share the AccessKey of your Alibaba Cloud account with others. You can use RAM to grant RAM users the minimum permissions necessary for them to complete their work, thereby improving the security of your enterprise’s information. RAM is required for almost all Alibaba Cloud services. STS is an Alibaba Cloud service that manages temporary access permissions for Alibaba Cloud accounts (or RAM users). Using STS, you can grant each RAM user (who you can manage under your Alibaba Cloud account) an access credential with a custom validity period and custom permissions. Then, RAM users can use this temporary access credential granted by STS to call Alibaba Cloud APIs or log on to the Alibaba Cloud console to access authorized resources. The LongVideo solution also uses STS to grant temporary access credentials. You need to grant the AliyunVODFullAccess permission (all ApsaraVideo VOD permissions) to RAM users. For more information, see STS authorization.

Quick start

Source code download

Download the LongVideo AppServer source code package.

Project description

The AppServer project supports the client in calling relevant methods and organizes data logic for the client. The directory structure of the project can be divided to the control layer, dao layer, service layer, and persistence layer.

Note: To use the source code, you need to replace the values of some parameters based on your configuration, such as the database configuration, the AccessKey ID and AccessKey secret, and relevant service configuration. For more information, see the following AppServer project configuration.

AppServer project configuration

Database

You must ensure that ApsaraDB for RDS is activated and the account and password are created for the ApsaraDB for RDS instance. Then, you need to replace the relevant configuration in source code files. For more information, see the application.properties file in the src/main/resources directory.

#DATABASE (After creating a database, you can use the username and password of the previously created account to log on to the database.)
spring.datasource.url =  jdbc:mysql://{dburl}:3306/{dbname}?useSSL=false&useUnicode=true&characterEncoding=UTF-8
spring.datasource.username =  <# The username used to log on to the ApsaraDB for RDS database. >
spring.datasource.password =  <# The password used to log on to the ApsaraDB for RDS database. >

ApsaraVideo VOD

You must ensure that ApsaraVideo VOD is activated and the account and password are created for the ApsaraDB for RDS instance. Then, you need to replace the relevant configuration in source code files. For more information, see the application.properties file in the src/main/resources directory.

#transcoding template ID
TEMPLATEGROUP_ID = <# The transcoding template ID for videos. >
LONGVIDEO_TRANSCODE_TEMPLATEGROUP_ID = <# The transcoding template ID for videos. >
TAB_TEMPLATEGROUP_ID = <# The template ID for Narrowband HD transcoding. >

#domain name
DOMAIN_NAME = <# The domain name, in the http://example.com/ format. >
AVATAR_DOMAIN_NAME = <# The domain name for the avatar. Set the value to http://example.aliyundoc.com/. >
VOD_REGIONID = cn-shanghai
CALLBACK_PRIVETEKEY = <# The authentication key for callback events. >
CALLBACK_NAME =  <# The callback URL. Set the value to http://ip:8080/vodcallback/callback. >
#for VOD services policy
policy =   {"Version": "1", "Statement": [ {"Action": ["vod:*"], "Resource": ["*"  ],"Effect": "Allow"}]}

Note: If you use a Chinese Alibaba Cloud account, the default value of the VOD_REGIONID parameter is cn-shanghai, indicating that the region is China (Shanghai). We recommend that you set other involved services in the same region. If you use an international Alibaba Cloud account, select the region as required.

STS and dynamic identity and authorization for cloud applications

You must ensure that RAM is activated and configured by referring to STS authorization, and a temporary access credential is obtained. In addition, RAM is used to allow applications to obtain the dynamic STS token of a RAM role for access to Alibaba Cloud APIs. For more information, see Dynamic identity and permission management of cloud applications. Then, you need to replace the values of the following parameters in source code files: REGION_CN_HANGZHOU, STS_API_VERSION, roleArn, roleSessionName, and roleName. For more information, see the application.properties file in the src/main/resources directory.

#ak information   
REGION_CN_HANGZHOU = cn-hangzhou
STS_API_VERSION = 2015-04-01
roleArn = <# The Alibaba Cloud Resource Name (ARN). >
roleSessionName = <# The name of the session that uses the temporary token. >
roleName = <# The name of the RAM role. >

Service packaging and compilation

Compile and package project files

Run the following command to go to the root directory of the disk where the project files are stored:

mvn clean package -Dmaven.test.skip=true

As shown in the preceding figure, the “BUILD SUCCESS” message indicates that the project files are packaged. You can find a JAR package named sdk-api-0.0.1-SNAPSHOT.jar in the target/ directory.

Deploy the AppServer

Upload the JAR package to the current user directory of your ECS instance. Run the following command to start the AppServer:

nohup java -jar sdk-api-0.0.1-SNAPSHOT.jar &

Access the project

To access the LongVideo console, you must compile and package console source code files. For more information, see Console source code integration. After you compile and package the console source code files, visit the following website to log on to the LongVideo console: http://{your server ip}:8080/resource/index.html#/login.

• The default username is admin, and the default password is 12345678.

Others

1. Note

You can modify the port number 8080 in the application.properties file in the src/main/resources directory of the Spring Boot project.

server.port=8080

{ip}: the public IP address of the ECS instance. You can obtain this information from the ECS console. If you have configured a domain name, you can also use an A record to point the domain name to this IP address so that you can use the domain name to access the project.

For example, use http://{ip}:{port}/ as the endpoint for calling methods.

1. View logsRun the following command to view logs:

tail -f nohup.out

AppServer front-end webpage configuration

You can find the front-end source code in the video-admin directory in the root directory of the AppServer project.To visit the front-end webpage, you need to configure the resources tag in the pom.xml file and change the directory name specified by the targetPath parameter to the package name of the front-end source code. For more information, see AppServer console source code integration.

Precautions

• To configure the LongVideo AppServer, ensure that you use the ApsaraVideo VOD SDK V2.12.0 or later, java-core V4.3.3 or later, and aliyun-java-sdk-core V4.3.3 or later.

• Use http or https as the prefix of the domain name or IP address as required. Do not use the https prefix if you do not activate the HTTPS service.

• When you compile the application.properties file, note the following points: The CALLBACK_PRIVETEKEY parameter indicates the authentication key. Set the same authentication key in the file and in the console. The CALLBACK_NAME parameter indicates the callback URL. The AVATAR_DOMAIN_NAME parameter indicates the domain name of the user avatar. The AVATAR_URL parameter indicates the user URL. You can set two or more of these parameters at the same time by separating them with a comma (,). For example, you can set AVATAR_DOMAIN_NAME and AVATAR_URL as follows: AVATAR_DOMAIN_NAME = http://example.com ,AVATAR_URL = heads/01.png,heads/02.png. The AUDIT_SETTINGS_FLAG parameter indicates the audit method. The value on indicates that you audit videos before publishing them. The value off indicates that you audit videos after publishing them.

Key business logic

Video publish

When you upload a video on the client, you also submit a first frame snapshot job, a video snapshot job (for taking eight video snapshots), and a video audit job asynchronously. Then, ApsaraVideo VOD takes video snapshots and audits the video. When ApsaraVideo VOD completes the audit, it sends a callback event notification to notify the AppServer of the audit result. After receiving the audit result, the AppServer distinguishes the first frame snapshot job from the video snapshot job based on the returned snapshot type and number of snapshots. If the first frame snapshot job is completed, the AppServer modifies the first frame data in the video library. If the video snapshot job is completed, the AppServer inserts the snapshot data (images and user ID) to the snapshot table.

Callback after the completion of a video snapshot job

After a video snapshot job is completed, ApsaraVideo VOD triggers a SnapshotComplete event and sends an event notification to notify the AppServer of the job result. For more information, see SnapshotComplete. In the AppServer project, you submit two snapshot jobs when you upload a video: a first frame snapshot job that takes a snapshot of the first frame in the video, and a video snapshot job that takes multiple video snapshots for you to view in the LongVideo console. After receiving a notification of the SnapshotComplete event, the AppServer checks the returned data as follows: Check the SubType parameter first. If the value is SpecifiedTime, the snapshots are taken through the SubmitSnapshotJob operation. Then, check the Status parameter. If the value is success, the snapshot job succeeded. Then, check the number of elements in the JSON-formatted array of the SnapshotInfos parameter. Multiple elements indicate multiple video snapshots. The AppServer stores the snapshots in the snapshot table. A single element indicates the first frame snapshot. The AppServer changes the snapshot status to successful in the vod_videos table and updates the first frame in the table to this snapshot.

Callback after the completion of a video audit job

After a video audit job is completed, ApsaraVideo VOD triggers an AIMediaAuditComplete event and sends an event notification to notify the AppServer of the job result. For more information, see AIMediaAuditComplete. After receiving this event notification, the AppServer checks the returned data as follows: Check the Status parameter first. If the value is success, the audit job succeeded. Then, check the Suggestion parameter of the Data parameter. If the value of the Suggestion parameter is pass, the video passes the audit. The AppServer changes the audit status to successful and calls a manual audit method to submit a non-Narrowband HD transcoding job. If the value of the Suggestion parameter is block, the video contains violations. The AppServer changes the audit status to failed. If the value of the Suggestion parameter is review, the video needs to be audited manually. The AppServer changes the audit status to to-be-reviewed. If the value of the Status parameter is fail, the audit job failed. The AppServer changes the audit status to failed.

Callback after the completion of a transcoding job

After a transcoding job is completed, ApsaraVideo VOD triggers a TranscodeComplete event and sends an event notification to notify the AppServer of the job result. For more information, see TranscodeComplete. After receiving this event notification, the AppServer checks the returned data as follows: Check the Status parameter first. If the value is success, the transcoding job succeeded. The AppServer changes the transcoding status to successful and stores the playback URL (FileUrl) and video ID (VideoId) of the transcoded video in the transcoding table. If the value is fail, the transcoding job failed. The AppServer changes the transcoding status to failed.