fix: Set HOSTNAME environment variable in Dockerfile

[yllhwa]

Summary

Adds the HOSTNAME environment variable to the Dockerfile to fix container accessibility issues on Windows with Docker Compose.

Problem

When running the container on Windows with Docker Compose, the Next.js standalone server listens on the container's hostname instead of 0.0.0.0, making the application inaccessible from the host network.

Related Issues:

• Fixes Windows 上使用 docker compose 运行，容器内监听 hostname 而不是 0.0.0.0 导致无法访问 #621 - Windows Docker Compose container listens on hostname instead of 0.0.0.0

Solution

Add ENV HOSTNAME=0.0.0.0 to the Dockerfile runner stage. Next.js standalone server reads the HOSTNAME environment variable (not HOST) to determine the binding address. Without this, the server falls back to default behavior which causes binding issues on Windows.

Changes

Core Changes

• deploy/Dockerfile: Added ENV HOSTNAME=0.0.0.0 environment variable alongside the existing HOST variable

Technical Details

Next.js standalone mode uses process.env.HOSTNAME to determine the server binding address:

const hostname = process.env.HOSTNAME || '0.0.0.0'

The existing ENV HOST=0.0.0.0 is not used by Next.js standalone server, so HOSTNAME must be explicitly set for proper container networking.

Testing

Manual Testing

1. Build the Docker image with the updated Dockerfile
2. Run with docker compose up on Windows
3. Verify the application is accessible from the host at localhost:3000

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Description enhanced by Claude AI

[gemini-code-assist]

Summary of Changes

Hello @yllhwa, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces a change to the Dockerfile to explicitly define the HOSTNAME environment variable. This modification ensures that applications running within the container have a consistent and predictable hostname, which can be crucial for network configurations and service discovery.

Highlights

• Dockerfile Configuration: Explicitly sets the HOSTNAME environment variable to 0.0.0.0 within the deploy/Dockerfile.

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[coderabbitai]

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📝 Walkthrough

Walkthrough

在deploy/Dockerfile的runner阶段添加了环境变量HOSTNAME=0.0.0.0，用于配置运行时主机名设置。现有的ENV HOST变量保持不变。

Changes

类别 / 文件	变化摘要
Docker配置 deploy/Dockerfile	在runner阶段新增环境变量HOSTNAME=0.0.0.0，配置容器运行时主机名解析

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	PR标题准确反映了主要变更：在Dockerfile中设置HOSTNAME环境变量，内容与代码改动完全相符。
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description check	✅ Passed	拉取请求的描述与代码改动相关，清晰地说明了在Docker文件中添加HOSTNAME环境变量的目的和上下文。

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[gemini-code-assist]

Code Review

This PR correctly sets the HOSTNAME environment variable for the Next.js standalone server in the production Dockerfile. However, this makes the existing HOST variable redundant and it should be removed for clarity. A more significant issue is that the same fix is required for the development Dockerfile (deploy/Dockerfile.dev) to ensure consistency between environments, as it currently uses the incorrect HOST variable and has not been updated in this pull request.

[gemini-code-assist]

While adding HOSTNAME is the correct fix for the Next.js standalone server, it makes the ENV HOST=0.0.0.0 on the previous line redundant. The standalone server only respects the HOSTNAME variable for setting the bind address. To improve code clarity and prevent future confusion, the now-unused HOST variable should be removed.

[greptile-apps]

Greptile found no issues!

From now on, if a review finishes and we haven't found any issues, we will not post anything, but you can confirm that we reviewed your changes in the status check section.

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[github-actions]

Code Review Summary

No significant issues identified in this PR.

PR Size: XS

• Lines changed: 1
• Files changed: 1

Review Coverage

• Logic and correctness - Clean
• Security (OWASP Top 10) - Clean
• Error handling - N/A (Dockerfile ENV declaration)
• Type safety - N/A (Dockerfile)
• Documentation accuracy - Clean
• Test coverage - N/A (Infrastructure change)
• Code clarity - Good

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Automated review by Claude AI