[Nacos cloud native] the first step of reading the source code is to start Nacos locally

Preface

Before we read Nacos Before source code , We have to understand Nacos do , And how to use it , This makes it easier for us to understand the source code ;

see Nacos Official documents of , We know Naocs It has the following characteristics :

• Configuration center
• Service registration and discovery
• …

Nacos It provides us with a management interface , To facilitate the configuration of data ; Let's take the whole Nacos The source code is cloned , Local boot ; Familiarize yourself with how to use it

start-up Nacos project

1. clone Nacos Source code

git clone https://github.com/alibaba/nacos.git 

Import to Idea in

2. To configure Mysql data source

Nacos Built in embedded derby database , But it is only suitable for development testing , It's not good for us to observe the data ; So let's change the database to Mysql

In the use of Mysql Before , You need to create nacos_config The database of sql File in module distribution Medium conf/nacos-mysql.sql ; Execute this file ;

In the module nacos/distribution Add Mysql Configuration file for

##  The database for mysql
spring.datasource.platform=mysql
##  Database number   Because there may be multiple data sources configured   Master-slave 
db.num=1
db.url.0=jdbc:mysql://XX.XX.XXX.XX:3306/nacos_config?characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true
db.user.0=name
db.password.0=password

3. Package and publish the project

Execute package command

mvn -Prelease-nacos clean install -U  -Dmaven.test.skip=true

Pack up , Execute startup script

sh distribution/target/nacos-server-{version}/nacos/bin/startup.sh -m standalone

here -m standalone Stand alone mode start , Other optional parameters are :

• -f [config/naming]
  Boot mode Only one module can be started ,config: Configuration center ; naming: Service registration and discovery , When not set, all modules will start

• -s Followed by the service package name ; The default value is nacos-server
  You can specify the startup Jar Package name ;
  

Check if the start is successful

After successful startup , You can access the management background
http://localhost:8848/nacos/index.html The password of the login account is : nacos
The management background after login

If you add parameters when you just start -f config Now all we see is Configuration Management and Namespace Two menu bars
For detailed explanation of use, please refer to the official documents Console manual

Nacos Configuration center database table structure description

tenant_info Tenant information table ( The namespace table )

Nacos be based on Namespace Help users logically isolate multiple namespaces , This can help users better manage tests 、 Advance 、 Production and other multi environment services and configurations , Let each environment have the same configuration （ Such as database data source ） You can define different values .

The data in this namespace is the existence table tenant_info in
tenant_info

Field	remarks
id	The primary key increases automatically
kp	Set value 1
tenant_id	Namespace id, It's a UUID character string
tenant_name	Namespace name
tenant_desc	Namespace description
create_source	founder
gmt_create	Creation time
gmt_modified	Modification time

(kp,tenant_id) Make up a unique constraint

config_info Configuration information table

All configured data is stored in this table ;

Field	describe
id	Since the primary key
data_id	data ID
group_id	Group ID, Default DEFAULT_GROUP
content	Configure the content , It's a longtext type
md5	content Of md5
tenant_id	Tenant ID, Corresponding tenant_ino Medium tenant_id
app_name	ascription App name
type	json、properties、text、xml And so on
gmt_create	Creation time
gmt_modified	Modification time
c_desc	describe

config_info_beta Gray configuration information

Nacos Grayscale publishing function in , If you click grayscale Publishing , And fill in the grayscale publishing server Ip; Information will be stored here ;

Field	describe
id	The primary key increases automatically
data_id	data id
group_id	Group id
app_name	apply name
content	Configure the content
beta_ips	Machines requiring grayscale Publishing , If ip In this , The configuration information will be obtained
md5	content Of md5
tenant_id	Tenant ID, Different namespaces
gmt_create	Creation time
gmt_modified	Modification time

(data_id,group_id,tenant_id) Make up a unique constraint

config_tags_relation tag A relational table

Each configuration file can be marked with tag label ; This table records the configuration file and tag Binding relationship of

Field	describe
id	Primary key .
tag_name	The tag name
tag_type	Label type
data_id	data id
group_id	Group id
tenant_id	Tenant ID, Different namespaces
nid	The primary key grows by itself

(id,tag_name,tag_type) Make up a unique constraint

his_config_info Historical configuration table

Nacos The historical configuration will be recorded , Used to facilitate rollback configuration ; By default, it exceeds 30 The record of days will be deleted ;

Field	describe
id	id
nid	Primary key , Self increasing
data_id	data id
group_id	Group id
app_name	apply name
content	Configure the content
md5	content Of md5
tenant_id	Tenant ID, Different namespaces
gmt_create	Creation time
gmt_modified	Modification time
op_type	I、U、D Operation type , Add, replace and delete

How to debug locally Jar Package start source code

Due to the above startup mode , We may not be able to do local Debug; But we can turn it on at startup Debug port , Through remote monitoring Debug Port to carry on Debug;

Let's modify the startup script first , Open the debug port to modify
file distribution/target/nacos-server-{version}/nacos/bin/startup.sh

#  Add debug port  6666 The debug port can be set at will 
JAVA_DEBUG_OPTS="-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,address=6666,server=y,suspend=n"

echo "$JAVA ${JAVA_DEBUG_OPTS} ${JAVA_OPT} " > ${
    BASE_DIR}/logs/start.out 2>&1 &
nohup $JAVA ${
    JAVA_DEBUG_OPTS} ${
    JAVA_OPT}  nacos.nacos >> ${
    BASE_DIR}/logs/start.out 2>&1 &

Restart

Stop the project first
sh distribution/target/nacos-server-{version}/nacos/bin/shutdown.sh
And then restart it
sh distribution/target/nacos-server-1.1.3/nacos/bin/startup.sh -m standalone

Successful launch , Check whether the debug port is open

There is already one 6666 The port of LISTEN It's in ;

Configuration debugging
stay Idea Create a new one in remote start-up ;

Start debugging
Start debugging ; Make a breakpoint , Then manage the back-end operations ; Look at the effect

Debugging successful

The project started , The debugging is also successful ; Then we can easily start reading the source code ！