For information on using this library in your app, see PostHog Docs.
This README is intended for developing the library itself.
Unit tests: run pnpm test
.
Cypress: run pnpm start
to have a test server running and separately pnpm cypress
to launch Cypress test engine.
Testing on IE11 requires a bit more setup. TestCafe tests will use the
playground application to test the locally built array.full.js bundle. It will
also verify that the events emitted during the testing of playground are loaded
into the PostHog app. By default it uses https://us.i.posthog.com and the
project with ID 11213. See the testcafe tests to see how to override these if
needed. For PostHog internal users ask @benjackwhite or @hazzadous to invite you
to the Project. You'll need to set POSTHOG_API_KEY
to your personal API key, and
POSTHOG_PROJECT_KEY
to the key for the project you are using.
You'll also need to sign up to BrowserStack. Note that if you are using CodeSpaces, these variables will already be available in your shell env variables.
After all this, you'll be able to run through the below steps:
nodemon -w src/ --exec bash -c "pnpm build-rollup"
.export BROWSERSTACK_USERNAME=xxx BROWSERSTACK_ACCESS_KEY=xxx
.npx testcafe "browserstack:ie" testcafe/e2e.spec.js
.You can use the create react app setup in playground/nextjs
to test posthog-js as an npm module in a Nextjs application.
posthog
locally on port 8000 (DEBUG=1 TEST=1 ./bin/start
).python manage.py setup_dev --no-data
on posthog repo, which sets up a demo account.http://localhost:8000/project/settings
and thencd playground/nextjs
and run NEXT_PUBLIC_POSTHOG_KEY='<your-local-api-key>' pnpm dev
Install pnpm to link a local version of posthog-js
in another JS project: npm install -g pnpm
We have 2 options for linking this project to your local version: via pnpm link or via local paths
posthog-js
, go to the package.json
of that file, and replace the posthog-js
dependency version number with file:<relative_or_absolute_path_to_local_module>
package.json
within posthog
, replace "posthog-js": "1.131.4"
with "posthog-js": "file:../posthog-js"
pnpm install
from the root of the project in which you just created a local pathThen, once this link has been created, any time you need to make a change to posthog-js
, you can run pnpm build
from the posthog-js
root and the changes will appear in the other repo.
pnpm link
posthog-js
directory: pnpm link --global
posthog
this means: pnpm link --global posthog-js && pnpm i && pnpm copy-scripts
)pnpm link --global posthog-js
from within posthog
Just put a bump patch/minor/major
label on your PR! Once the PR is merged, a new version with the appropriate version bump will be released, and the dependency will be updated in posthog/PostHog – automatically.
If you forget to add the label, don't try to update the version locally as you won't be able to push that commit to the main branch. Instead, just make a new PR.
To release an alpha or beta version, you'll need to use the CLI locally:
Only one person is set as a collaborator on NPM, so they're the only person that can manually publish alphas
Make sure you're a collaborator on posthog-js
in npm (check here).
Make sure you're logged into the npm CLI (npm login
).
Check out your work-in-progress branch (do not release an alpha/beta from main
).
Run the following commands, using the same bump level (major/minor/patch) as your PR:
npm version [premajor | preminor | prepatch] --preid=beta
npm publish --tag beta
git push --tags
Enjoy the new prerelease version. You can now use it locally, in a dummy app, or in the main repo.
Use the "release alpha" label on your PR to have an alpha version published automatically. This automation currently doesn't check whether an alpha exists for the version it will try to publish. If you need to publish two alphas from one PR you'll need to fix that
Remember that these versions are public and folk might use them, so make sure they're not too alpha 🙈