Service Wait

A lightweight CLI tool that waits for HTTP, MongoDB, or PostgreSQL endpoints to become available before proceeding. Useful as an init container or entrypoint wrapper in containerised deployments.

Features

• HTTP – probe one or multiple HTTP endpoints
• PostgreSQL – wait for a Postgres database to accept connections
• MongoDB – wait for a Mongo instance to respond to pings
• Configurable timeout and polling interval
• Configuration via CLI flags or environment variables

Install

Prerequisites

• mise

mise trust
mise install

Build from source

make build        # outputs bin/service-wait
make install      # installs to ~/.local/bin

Docker

docker build -t service-wait .

Use in a Docker image (multi-stage)

Copy the binary into your own image using a multi-stage build:

FROM ghcr.io/ororatech/service-wait:v0.0.1@sha256:f76661dd68c5bfef49712400d8cd64d46e4f8ab932f644d628b4cee0294b1e28 AS service-wait

FROM alpine:3

COPY --from=service-wait /ko-app/service-wait /usr/local/bin/service-wait

ENTRYPOINT ["service-wait"]

Usage

service-wait [flags]

Flags

Flag	Short	EnvVar	Default	Description
--url	-u	SERVICE_WAIT_URL		HTTP endpoint to probe
--urls	-U	SERVICE_WAIT_URLS		Multiple HTTP endpoints (comma-separated)
--timeout	-t	SERVICE_WAIT_TIMEOUT	30s	Max time to wait
--interval	-i	SERVICE_WAIT_INTERVAL	30s	Polling interval
--psql-host	-H	SERVICE_WAIT_PSQL_HOST / PGHOST		PostgreSQL host
--psql-port	-p	SERVICE_WAIT_PSQL_PORT / PGPORT	5432	PostgreSQL port
--psql-user		SERVICE_WAIT_PSQL_USER / PGUSER		PostgreSQL user
--psql-password	-P	SERVICE_WAIT_PSQL_PASSWORD / PGPASSWORD		PostgreSQL password
--psql-database	-d	SERVICE_WAIT_PSQL_DATABASE / PGDATABASE		PostgreSQL database
--psql-sslmode	-s	SERVICE_WAIT_PSQL_SSLMODE / PGSSLMODE	disable	PostgreSQL SSL mode
--psql-dsn		SERVICE_WAIT_PSQL_DSN		PostgreSQL DSN (overrides individual flags)
--mongo-host		SERVICE_WAIT_MONGO_HOST		MongoDB host
--mongo-port		SERVICE_WAIT_MONGO_PORT	27017	MongoDB port
--mongo-user		SERVICE_WAIT_MONGO_USER		MongoDB user
--mongo-password		SERVICE_WAIT_MONGO_PASSWORD		MongoDB password
--mongo-database		SERVICE_WAIT_MONGO_DATABASE		MongoDB database
--mongo-auth-source		SERVICE_WAIT_MONGO_AUTH_SOURCE		MongoDB auth source
--verbose	-V	SERVICE_WAIT_DEBUG	false	Enable debug logging

Examples

Wait for an HTTP endpoint:

service-wait --url http://localhost:8080/health --timeout 60s --interval 2s

Wait for PostgreSQL:

service-wait --psql-host localhost --psql-user postgres --psql-password secret --psql-database mydb

Wait for MongoDB:

service-wait --mongo-host localhost --mongo-user admin --mongo-password secret --mongo-database mydb

Using environment variables:

export SERVICE_WAIT_URL=http://localhost:8080/health
export SERVICE_WAIT_TIMEOUT=60s
service-wait

Development

make build    # compile
make test     # run tests (requires Docker for testcontainers)
make fmt      # format code
make vet      # run go vet
make tidy     # tidy go modules

License

MIT