echomirror

Bun CLI for downloading EchoVideo/Echo360 recordings from all enrolled courses or a selected course.

Authentication

echomirror uses the Echo360 Cookie header stored in:

./cookies

The file should contain the raw cookie value. Do not include:

Cookie:

To get the cookie:

1. Login to Echo360
2. Open DevTools → Network
3. Reload the page
4. Open an Echo360 request
5. Copy the Cookie request header
6. Save it to ./cookies

You can also provide it once:

bun run echomirror.ts --token 'COOKIE_VALUE'

The value is saved to ./cookies and checked on future runs.

Usage

bun run echomirror.ts --help

bun run echomirror.ts --list

bun run echomirror.ts --course 2026_1:comp4403

bun run echomirror.ts --course comp4403

bun run echomirror.ts --all

--list shows available course IDs.

--course accepts either the full ID or a unique course code.

Destination

Default:

~/Downloads/Docs/uq/{year_sem}/{course}/recordings/{week}_{lecnum}_{lecname}.mp4

Example:

bun run echomirror.ts --all \
  --dest '~/Downloads/Docs/uq/{year}/{course}/recordings/{week}_{lecnum}_{lecname}'

Available fields:

Field	Example
{year}	2026
{semester}	1
{year_sem}	2026_1
{course}	comp4403
{week}	01
{lecnum}	02
{lecname}	introduction
{id}	Echo360 lesson ID

Ledger

echomirror keeps a .ledger.json file in the destination root.

Example:

{
  "2026_1/comp4403/recordings/01_01_intro.mp4": "lesson-id"
}

The ledger links downloaded files to Echo360 lesson IDs.

If the destination template changes, echomirror moves existing files instead of downloading them again.

Concurrency

Configure concurrency with:

ECHO_CONCURRENCY=6
ECHO_HTTP_CONCURRENCY=12
ECHO_SEGMENT_CONCURRENCY=8

Checks

npm run typecheck
npm test
npm run build

Run directly:

bun run echomirror.ts

Errors and retries

If Echo returns expired media links or a 403 response, echomirror reloads the lesson page and retries with fresh URLs.

Skipped recordings show the reason:

SKIP file.mp4 - destination already exists
SKIP file.mp4 - no downloadable video found

This is closer to what a GitHub README should look like: quick start first, details only where needed.