Wait4X allows you to wait for a port or a service to enter the requested state, with a customizable timeout and interval time.
Table of Contents
- Supports various protocols:
- TCP
- HTTP
- Supports various services:
- Redis
- MySQL
- PostgreSQL
- InfluxDB
- MongoDB
- RabbitMQ
- Temporal
- Reverse Checking: Invert the sense of checking to find a free port or non-ready services
- Parallel Checking: You can define multiple inputs to be checked
- Exponential Backoff Checking: Retry using an exponential backoff approach to improve efficiency and reduce errors.
- CI/CD Friendly: Well-suited to be part of a CI/CD pipeline step
- Cross Platform: One single pre-built binary for Linux, Mac OSX, and Windows
- Importable: Beside the CLI tool, Wait4X can be imported as a pkg in your Go app
- Command execution: Execute your desired command after a successful wait
There are many ways to install Wait4X
Wait4X provides automatically updated Docker images within Docker Hub. It is possible to always use the latest stable tag.
Pull the image from the docker index.
docker pull atkrad/wait4x:latestthen you can launch the wait4x container.
docker run --rm --name='wait4x' \
atkrad/wait4x:latest --helpChoose the file matching the destination platform from the release page, copy the URL and replace the URL within the commands below:
curl -#LO https://github.com/atkrad/wait4x/releases/latest/download/wait4x-linux-amd64.tar.gz
tar --one-top-level -xvf wait4x-linux-amd64.tar.gz
cp ./wait4x-linux-amd64/wait4x /usr/local/bin/wait4xcurl -#LO https://github.com/atkrad/wait4x/releases/latest/download/wait4x-darwin-amd64.tar.gz
tar --one-top-level -xvf wait4x-darwin-amd64.tar.gz
cp ./wait4x-darwin-amd64/wait4x /usr/local/bin/wait4xcurl -#LO https://github.com/atkrad/wait4x/releases/latest/download/wait4x-windows-amd64.tar.gz
tar --one-top-level -xvf wait4x-windows-amd64.tar.gzWait4X generates checksum for all binaries with sha256sum to prevent against unwanted modification of binaries.
To validate the archive files, download the checksum file which ends in .sha256sum for the archive file that you downloaded and use
the sha256sum command line tool.
curl -#LO https://github.com/atkrad/wait4x/releases/latest/download/wait4x-linux-amd64.tar.gz.sha256sum
sha256sum --check wait4x-linux-amd64.tar.gz.sha256sumYou can find the Wait4X package in some Linux distributions.
You can install the wait4x package from the official sources:
apk add wait4xYou can install the wait4x package from the Arch User Repository:
yay -S wait4x# If you want checking just tcp connection
wait4x tcp 127.0.0.1:9090# If you want checking just http connection
wait4x http https://ifconfig.co
# If you want checking http connection and expect specify http status code
wait4x http https://ifconfig.co --expect-status-code 200
# If you want checking http connection, status code and match the response body.
# Note: You can write any regex that compatible with Golang syntax (https://pkg.go.dev/regexp/syntax#hdr-Syntax)
wait4x http https://ifconfig.co/json --expect-status-code 200 --expect-body='"country":\s"Netherlands"'
# If you want to check a http response header
# NOTE: the value in the expected header is regex.
# Sample response header: Authorization Token 1234ABCD
# You can match it by these ways:
# Full key value:
wait4x http https://ifconfig.co --expect-header "Authorization=Token 1234ABCD"
# Value starts with:
wait4x http https://ifconfig.co --expect-header "Authorization=Token"
# Regex value:
wait4x http https://ifconfig.co --expect-header "Authorization=Token\s.+"
# Body JSON value:
# Note: the value in the expected JSON will be processed by gjson.
# Note: the complete response MUST be in JSON format to be processed. If one part of the response is JSON
# and the rest is something else like HTML, please use --expect-body instead.
# To know more about JSON syntax https://github.com/tidwall/gjson/blob/master/SYNTAX.md
wait4x http https://ifconfig.co/json --expect-body-json "user_agent.product"
# Body XPath
wait4x http https://www.kernel.org/ --expect-body-xpath "//*[@id="tux-gear"]"
# Request headers:
wait4x http https://ifconfig.co --request-header "Content-Type: application/json" --request-header "Authorization: Token 123"
# Enable exponential backoff retry
wait4x http https://ifconfig.co --expect-status-code 200 --backoff-policy exponential --backoff-exponential-max-interval 120s --timeout 120s# Checking Redis connection
wait4x redis redis://127.0.0.1:6379
# Specify username, password and db
wait4x redis redis://user:password@localhost:6379/1
# Checking Redis connection over unix socket
wait4x redis unix://user:password@/path/to/redis.sock?db=1
# Checking a key existence
wait4x redis redis://127.0.0.1:6379 --expect-key FOO
# Checking a key existence and matching the value
# Note: You can write any regex that compatible with Golang syntax (https://pkg.go.dev/regexp/syntax#hdr-Syntax)
wait4x redis redis://127.0.0.1:6379 --expect-key "FOO=^b[A-Z]r$"# Checking MySQL TCP connection
wait4x mysql user:password@tcp(localhost:5555)/dbname
# Checking MySQL UNIX Socket connection
wait4x mysql username:password@unix(/tmp/mysql.sock)/myDatabaseSyntax for the database connection string: https://github.com/go-sql-driver/mysql#dsn-data-source-name
# Checking PostgreSQL TCP connection
wait4x postgresql 'postgres://bob:[email protected]:5432/mydb?sslmode=disable'
# Checking PostgreSQL Unix socket connection
wait4x postgresql 'postgres://bob:secret@/mydb?host=/var/run/postgresql'Syntax for the database URL: https://pkg.go.dev/github.com/lib/pq
# Checking InfluxDB connection
wait4x influxdb http://localhost:8086# Checking MongoDB connection
wait4x mongodb 'mongodb://127.0.0.1:27017'
# Checking MongoDB connection with credentials and options
wait4x mongodb 'mongodb://user:[email protected]:27017/?maxPoolSize=20&w=majority'# Checking RabbitMQ connection
wait4x rabbitmq 'amqp://127.0.0.1:5672'
# Checking RabbitMQ connection with credentials and vhost
wait4x rabbitmq 'amqp://guest:[email protected]:5672/vhost'# Checking just Temporal server health check
wait4x temporal server 127.0.0.1:7233
# Checking insecure Temporal server (no TLS)
wait4x temporal server 127.0.0.1:7233 --insecure-transport
# Checking a task queue that has registered workers (pollers) or not
wait4x temporal worker 127.0.0.1:7233 --namespace __YOUR_NAMESPACE__ --task-queue __YOUR_TASK_QUEUE__
# Checking the specific a Temporal worker (pollers)
wait4x temporal worker 127.0.0.1:7233 --namespace __YOUR_NAMESPACE__ --task-queue __YOUR_TASK_QUEUE__ --expect-worker-identity-regex ".*@__HOSTNAME__@.*"We need to wait for something in order to execute something else. This feature is also supported by using -- after a feature parameter.
Let's have some scenarios:
- As soon as the MySQL server becomes ready, run a Django migration:
wait4x mysql username:password@unix(/tmp/mysql.sock)/myDatabase -- django migrate- As soon as the new version of the website becomes ready, send an email to the support team:
wait4x http https://www.kernel.org/ --expect-body-xpath "//*[@id="website-logo"]" -- mail -s "The new version of the website has just been released" support@company < /dev/null- Chain type: when PostgreSQL becomes ready, then wait for RabbitMQ, when it becomes ready, then run the integration tests:
wait4x postgresql 'postgres://bob:secret@/mydb?host=/var/run/postgresql' -t 1m -- wait4x rabbitmq 'amqp://guest:[email protected]:5672/vhost' -t 30s -- ./integration-tests.sh- Using an environment variable in the command:
EMAIL="support@company" wait4x http https://www.kernel.org/ --expect-body-xpath "//*[@id="website-logo"]" -- mail -s "New version of the website has just released" $EMAIL < /dev/null
# Or
export EMAIL="support@company"
wait4x http https://www.kernel.org/ --expect-body-xpath "//*[@id="website-logo"]" -- mail -s "New version of the website has just released" $EMAIL < /dev/null