Configuring Different Types of Hooks
In this guide, we are going to discuss how to configure different types of hooks. Here, we will give some examples of different configurations.
HTTPGet
httpGet hook allows sending an HTTP GET request to an HTTP server before and after the backup/restore process. The following configurable fields are available for httpGet hook.
| Field | Field Type | Data Type | Usage |
|---|---|---|---|
host | Optional | String | Specify the name of the host where the GET request will be sent. If you don’t specify this field, Stash will use the hook executor Pod IP as host. |
port | Required | Integer or String | Specify the port where the HTTP server is listening. You can specify a numeric port or the name of the port in case of the HTTP server is running in the same pod where the hook will be executed. If you specify the port name, you must specify the containerName field of the hook. |
path | Required | String | Specify the path to access on the HTTP server. |
scheme | Required | String | Specify the scheme to use to connect with the host. |
httpHeaders | Optional | Array of Objects | Specify a list of custom headers to set in the request. |
Examples:
- Hook with
hostandportare specified:
preBackup:
httpGet:
host: my-host.demo.svc
port: 8080
path: "/"
scheme: HTTP
- Hook to extract
hostandportfrom the hook executor pod:
preBackup:
httpGet:
port: my-port
path: "/"
scheme: HTTP
containerName: my-container
- Hook for sending custom header in the HTTP request:
preBackup:
httpGet:
host: my-host.demo.svc
port: 8080
path: "/"
scheme: HTTP
httpHeaders:
- name: "User-Agent"
value: "stash/0.9.x"
HTTPPost
httpPost hook allows sending an HTTP POST request to an HTTP server before and after the backup/restore process. The following configurable fields are available for httpPost hook.
| Field | Field Type | Data Type | Usage |
|---|---|---|---|
host | Optional | String | Specify the name of the host where the POST request will be sent. If you don’t specify this field, Stash will use the hook executor Pod IP as host. |
port | Required | Integer or String | Specify the port where the HTTP server is listening. You can specify a numeric port or the name of the port if your HTTP server is running in the same pod where the hook will be executed. If you specify the port name, you must specify the containerName field of the hook. |
path | Required | String | Specify the path to access on the HTTP server. |
scheme | Required | String | Specify the scheme to use to connect with the host. |
httpHeaders | Optional | Array of Objects | Specify a list of custom headers to set in the request. |
body | Optional | String | Specify the data to send in the request body. |
form | Optional | Array of Objects | Specify the data to send as URL encoded form with the request. |
Examples:
- Send JSON data in the request body:
preBackup:
httpPost:
host: my-service.mynamespace.svc
path: /demo
port: 8080
scheme: HTTP
httpHeaders:
- name: Content-Type
value: application/json
body: '{
"name": "john doe",
"age": "28"
}'
- Send URL encoded form in the request:
preBackup:
httpPost:
host: my-service.mynamespace.svc
path: /demo
port: 8080
scheme: HTTP
form:
- key: "name"
values: ["john doe"]
- key: "age"
values: ["28"]
TCPSocket
tcpSocket hook allows running a check against a TCP port to verify whether it is open or not. The following configurable fields are available for tcpSocket hook.
| Field | Field Type | Data Type | Usage |
|---|---|---|---|
host | Optional | String | Specify the name of the host where the server is running. If you don’t specify this field, Stash will use the hook executor Pod IP as host. |
port | Required | Integer or String | Specify the port to check. You can specify a numeric port or the name of the port when your server is running in the same pod where the hook will be executed. If you specify the port name, you must specify the containerName field of the hook. |
Examples:
- Hook with
hostandportfield specified.
preBackup:
tcpSocket:
host: my-host.demo.svc
port: 8080
- Hook to extract
hostandportfrom the hook executor pod.
preBackup:
tcpSocket:
port: my-port
containerName: my-container
Exec
exec hook allows running commands inside a container before or after the backup/restore process. The following configurable fields are available for exec hook.
| Field | Field Type | Data Type | Usage |
|---|---|---|---|
command | Required | Array of Strings | Specify a list of commands to execute. |
If you don’t specify
containerNameforexechook, the command will be executed into the 0th container of the respective pod.
Examples:
- Hook to remove old corrupted data before restore:
preRestore:
exec:
command: ["/bin/sh","-c","rm -rf /corrupted/data/directory"]
containerName: my-container
- Hook to make a MySQL database read-only before backup:
preBackup:
exec:
command:
- /bin/sh
- -c
- mysql -u root --password=$MYSQL_ROOT_PASSWORD -e "SET GLOBAL super_read_only = ON;"
containerName: mysql
- Hook to make a MySQL database writable after backup:
postBackup:
exec:
command:
- /bin/sh
- -c
- mysql -u root --password=$MYSQL_ROOT_PASSWORD -e "SET GLOBAL super_read_only = OFF;"
containerName: mysql
- Hook to remove corrupted MySQL database before restoring:
preRestore:
exec:
command:
- /bin/sh
- -c
- mysql -u root --password=$MYSQL_ROOT_PASSWORD -e "DROP DATABASE companyRecord;"
containerName: mysql
- Hook to apply some migration after restoring a MySQL database:
postRestore:
exec:
command:
- /bin/sh
- -c
- mysql -u root --password=$MYSQL_ROOT_PASSWORD -e "RENAME TABLE companyRecord.employee TO companyRecord.salaryRecord;"
containerName: mysql
If the above hooks do not cover your use cases or you have any questions regarding the hooks, please feel free to open an issue here.