Docker Container Name Regex for Python
/^[a-zA-Z0-9][a-zA-Z0-9_\-.]{0,253}$/What this pattern does
This page provides a well-structured, multi-part regular expression for matching docker container name, ported and verified for Python. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.
Python Implementation
# Docker Container Name
# ReDoS-safe | RegexVault — Dev & Systems > Docker
import re
docker_container_name_pattern = re.compile(r'^[a-zA-Z0-9][a-zA-Z0-9_\-.]{0,253}$')
def validate_docker_container_name(value: str) -> bool:
return bool(docker_container_name_pattern.fullmatch(value))
# Example
print(validate_docker_container_name("my-container")) # TrueTest Cases
Matches (Valid) | Rejects (Invalid) |
|---|---|
my-container | -container |
webapp_1 | .container |
db.primary | /container |
nginx | container name |
app-server-01 | — |
When to use this pattern
This pattern is drawn from the Dev & Systems > Docker category and carries a ReDoS-safe certification. That matters for Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.
Common Pitfalls
Container names in Docker Compose are auto-prefixed with the project name. Account for this prefix when referencing containers externally.
Technical Notes
Docker container names must be unique within a Docker daemon. Container names are used for DNS resolution within Docker networks.
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