tests — media

tests — media

This document describes the tests/media/media-pipeline.test.ts module, which contains the comprehensive test suite for the MediaPipeline class. Its primary purpose is to ensure the robustness, correctness, and expected behavior of the media processing and management functionalities provided by MediaPipeline.

Module Purpose

The media-pipeline.test.ts module serves as the validation layer for the MediaPipeline class located in src/media/media-pipeline.ts. It employs a series of unit and integration tests to cover various aspects of media file handling, including type detection, ingestion, storage management, lifecycle hooks, and cleanup.

By running these tests, developers can confirm that:

• Media files are correctly identified and processed.
• Resource limits (file size, total storage) are enforced.
• Temporary files are managed and cleaned up effectively.
• Custom processing hooks can be registered and executed.
• The MediaPipeline instance behaves predictably throughout its lifecycle.

Test Environment Setup

The tests utilize a dedicated temporary directory structure to isolate test runs and prevent interference with the actual file system.

graph TD
    A[Test Suite Start] --> B{beforeEach};
    B --> C[Clean TEST_DIR];
    C --> D[Create TEST_DIR];
    D --> E[Initialize MediaPipeline];
    E --> F[Run Test Case];
    F --> G{afterEach};
    G --> H[Dispose MediaPipeline];
    H --> I[Clean TEST_DIR];
    I --> J[Test Suite End];

• TEST_DIR: __test-tmp__ within the test file's directory. This is the root for all temporary files created during tests.
• TEMP_DIR: __test-tmp__/pipeline-tmp. This is the specific directory where MediaPipeline stores its ingested files.
• createTestFile(name, sizeBytes): A utility function to quickly create dummy files within TEST_DIR for testing ingestion scenarios.

Lifecycle Hooks (beforeEach, afterEach):

• beforeEach:
• Ensures TEST_DIR is clean by recursively removing it if it exists.
• Recreates TEST_DIR and its subdirectories.
• Initializes a new MediaPipeline instance with specific configuration:
• tempDir: TEMP_DIR
• maxFileSizeMb: 1 MB
• maxTotalSizeMb: 2 MB
• autoCleanupMs: 60 seconds
• afterEach:
• Calls pipeline.dispose() to ensure all temporary files managed by the pipeline are removed.
• Recursively removes TEST_DIR to clean up any remaining test artifacts.

Core Functionality Tested

The tests are organized into describe blocks, each focusing on a specific method or aspect of the MediaPipeline class.

detectType

This suite verifies the static method MediaPipeline.detectType(path), which infers a generic MediaType (e.g., 'image', 'audio', 'video', 'document', 'unknown') based on the file extension.

• Verification: Uses it.each to test a wide range of common file extensions (e.g., .png, .mp3, .mp4, .pdf, .xyz) and asserts that the correct MediaType is returned.

detectMimeType

Similar to detectType, this suite tests the static method MediaPipeline.detectMimeType(path), which infers the standard MIME type (e.g., 'image/png', 'audio/mpeg') from the file extension.

• Verification: Employs it.each to check various extensions and their corresponding expected MIME types, including a fallback to application/octet-stream for unknown types.

ingest

This is a critical suite, testing the pipeline.ingest(srcPath) method responsible for bringing external files into the pipeline's management.

• Successful Ingestion: Verifies that a valid source file is copied to the TEMP_DIR, and the returned object is a MediaFile with correct id, type, mimeType, sizeBytes, and tempPath.
• Error Handling:
• Asserts that ingesting a non-existent file returns an error object.
• Confirms that files exceeding maxFileSizeMb are rejected with an appropriate error message.
• Tests the maxTotalSizeMb limit, ensuring that subsequent ingestions are rejected once the total managed size is exceeded.
• Event Emission: Uses jest.fn() to verify that the ingested event is emitted upon successful file ingestion, passing the MediaFile object as an argument.

get

Tests the pipeline.get(id) method for retrieving a MediaFile by its unique identifier.

• Retrieval: Verifies that a previously ingested file can be retrieved using its ID, and the returned object matches the original MediaFile.
• Unknown ID: Asserts that undefined is returned for non-existent IDs.

list

This suite checks the pipeline.list(type?) method, which provides a way to enumerate managed files.

• All Files: Verifies that list() without arguments returns all currently managed MediaFile objects.
• Filtered by Type: Asserts that list(type) correctly filters files by their MediaType (e.g., list('image')).

remove

Tests the pipeline.remove(id) method, which deletes a managed file from the pipeline and the file system.

• Successful Removal: Verifies that remove() returns true for a valid ID, the file is no longer retrievable via get(), its temporary file is deleted from disk, and the totalSize tracked by the pipeline is updated.
• Unknown ID: Asserts that remove() returns false for non-existent IDs.

hooks

This suite validates the mechanism for registering and processing custom logic via MediaPipelineHooks.

• Hook Registration and Execution:
• Registers hooks for different mediaTypes.
• Verifies that pipeline.processHooks(fileId) correctly identifies and executes only the hooks matching the MediaType of the specified file.
• Asserts that the results of the process function are returned.
• Unknown File: Confirms that processHooks() returns an empty array for non-existent file IDs.
• Nullable Hooks: Ensures that hooks returning null are filtered out from the results.

cleanup

Tests the pipeline.cleanup() method, which removes files that have exceeded their autoCleanupMs retention period.

• Expired File Removal:
• Ingests a file.
• Manually backdates the createdAt timestamp of the ingested file to simulate expiration.
• Initializes a new pipeline (to avoid interfering with the main test pipeline's state) and transfers the expired file reference.
• Calls cleanup() and asserts that the expired file is removed and the count of removed files is correct.

dispose

This suite verifies the pipeline.dispose() method, which is responsible for cleaning up all resources managed by the pipeline.

• Full Cleanup:
• Ingests a file.
• Calls dispose().
• Asserts that the temporary file is removed from disk, pipeline.list() returns an empty array, and pipeline.getTotalSize() is zero.

Connections to the Codebase

This test module directly interacts with:

• ../../src/media/media-pipeline.js: The MediaPipeline class, MediaFile interface, and MediaType enum are imported and thoroughly tested.
• fs and path (Node.js built-in modules): Used for creating, writing, checking existence, and removing files and directories in the test environment.
• jest: The testing framework providing describe, it, expect, beforeEach, afterEach, and jest.fn().