fix: return io.ReadCloser instead of io.Reader

[nstapelbroek]

Hi friends,

All download methods (DownloadFile, DownloadTranslation, and mt.Downloader.File) were returning io.Reader instead of io.ReadCloser, even though the underlying Client.Get() returns io.ReadCloser. This prevented callers from closing the HTTP response body, causing connection leaks.

I've updated the methods and their signatures. SDK clients should now be able to prevent memory leaks 🥳

[gemini-code-assist]

Summary of Changes

Hello @nstapelbroek, 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 addresses a critical resource management issue by modifying the return types of several download-related functions. Previously, these functions returned io.Reader, which did not provide a mechanism for callers to close the underlying HTTP response bodies, leading to connection leaks. By changing the return type to io.ReadCloser, SDK clients can now explicitly close these resources, ensuring proper cleanup and preventing resource exhaustion.

Highlights

• Return Type Change: All download methods (DownloadFile, DownloadTranslation, and mt.Downloader.File) now return io.ReadCloser instead of io.Reader.
• Resource Management: This change allows callers to properly close the underlying HTTP response body, preventing potential connection and memory leaks.
• Interface and Implementation Updates: The APIClient interface and the httpDownloader implementation have been updated to reflect the new return type.

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[Copilot]

Pull request overview

This PR updates download-related APIs to return io.ReadCloser instead of io.Reader, allowing callers to properly close HTTP response bodies and avoid connection leaks.

Changes:

• Change HttpAPIClient.DownloadFile to return io.ReadCloser and propagate the underlying Client.Get body directly.
• Change HttpAPIClient.DownloadTranslation to return io.ReadCloser.
• Update the APIClient and mt.Downloader interfaces (and httpDownloader.File implementation) to use io.ReadCloser for downloaded content.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
client_download_translation.go	Adjusts DownloadTranslation return type to io.ReadCloser to expose a closable response body.
client_download_file.go	Adjusts DownloadFile return type to io.ReadCloser to expose a closable response body.
client.go	Updates APIClient interface method signatures to match the new io.ReadCloser return types.
api/mt/downloader.go	Updates the Downloader interface and httpDownloader.File implementation to return io.ReadCloser for MT file downloads.

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[gemini-code-assist]

Code Review

This pull request correctly addresses a potential connection leak by changing the return type of download methods from io.Reader to io.ReadCloser. This allows callers to properly close the underlying HTTP response body. The changes are consistent across all modified interfaces and implementations. My review includes several suggestions to improve the documentation for these methods, making it explicit that the caller is responsible for closing the returned io.ReadCloser. This will improve the clarity of the API and help prevent future misuse.

[gemini-code-assist]

With the return type changed to io.ReadCloser, it's crucial to document that the caller is responsible for closing it. Please add a comment to the method signature to make this contract explicit and prevent resource leaks. For example: // File downloads a file. The caller must close the returned ReadCloser.

[gemini-code-assist]

The comment for this function is // File downloads file. Please update it to be more descriptive and to mention that the caller is responsible for closing the returned io.ReadCloser.

[gemini-code-assist]

To make the API contract clearer and prevent resource leaks, please add comments to DownloadFile and DownloadTranslation indicating that the caller is responsible for closing the returned io.ReadCloser.

[gemini-code-assist]

Please update the function's documentation (// DownloadFile downloads original file from project.) to mention that the caller must close the returned io.ReadCloser.

[gemini-code-assist]

Please update this function's documentation to clarify that the caller is responsible for closing the returned io.ReadCloser.