The client-side of the Chrome DevTools, including all JS & CSS to run the DevTools webapp.
The frontend is available on chromium.googlesource.com.
Please be aware that DevTools follows additional development guidelines.
In order to make changes to DevTools frontend, build, run, test, and submit changes, several workflows exist. Having depot_tools set up is a common prerequisite.
This workflow will ensure that your local setup is equivalent to how Chromium infrastructure tests your change. It also allows you to develop DevTools independently of the version in your Chromium checkout. This means that you don't need to update Chromium often, in order to work on DevTools.
In chromium/src
, run gclient sync
to make sure you have installed all required submodules.
gclient sync
Then, disable gclient sync
for DevTools frontend inside of Chromium by editing .gclient
config. From chromium/src/
, simply run
vim $(gclient root)/.gclient
In the custom_deps
section, insert this line:
"src/third_party/devtools-frontend/src": None,
Then run
gclient sync -D
This removes the DevTools frontend dependency. We now create a symlink to refer to the standalone checkout (execute in chromium/src
and make sure that third_party/devtools-frontend
exists):
(Note that the folder names do NOT include the trailing slash)
ln -s path/to/standalone/devtools-frontend third_party/devtools-frontend/src
Running gclient sync
in chromium/src/
will update dependencies for the Chromium checkout.
Running gclient sync
in chromium/src/third_party/devtools-frontend/src
will update dependencies for the standalone checkout.
As a standalone project, Chrome DevTools frontend can be checked out and built independently from Chromium. The main advantage is not having to check out and build Chromium. However, there is also no way to run layout tests in this workflow.
To check out the source for DevTools frontend only, follow these steps:
mkdir devtools
cd devtools
fetch devtools-frontend
To build, follow these steps:
cd devtools-frontend
gn gen out/Default
autoninja -C out/Default
The resulting build artifacts can be found in out/Default/resources/inspector
.
To update to latest tip of tree version:
git fetch origin
git checkout origin/master
gclient sync
These steps work with Chromium 79 or later. To run the production build, use
(Requires brew install coreutils
on Mac.)
<path-to-chrome>/chrome --custom-devtools-frontend=file://$(realpath out/Default/resources/inspector)
To run the debug build (directly symlinked to the original unminified source files),
build both Chromium and DevTools frontend with the GN flag debug_devtools=true
, and use
<path-to-chrome>/chrome --custom-devtools-frontend=file://$(realpath out/Default/resources/inspector/debug)
You can inspect DevTools with DevTools by undocking DevTools and then open the developers tools (F12 on Windows/Linux, Cmd+Option+I on Mac).
Test are available by running scripts in scripts/test/
.
Usual steps for creating a change work out of the box.
- To sync dependencies from Chromium to DevTools frontend, use
scripts/deps/roll_deps.py
. - To roll the HEAD commit of DevTools frontend into Chromium, use
scripts/deps/roll_to_chromium.py
. - To update DevTools frontend's DEPS, use
roll-dep
.
DevTools frontend can also be developed as part of the full Chromium checkout. This workflow can be used to make small patches to DevTools as a Chromium engineer. However, it is different to our infrastructure setup and how to execute general maintenance work.
Follow instructions to check out Chromium. DevTools frontend can be found under third_party/devtools-frontend/src/
.
Refer to instructions to build Chromium. To only build DevTools frontend, use devtools_frontend_resources
as build target. The resulting build artifacts for DevTools frontend can be found in out/Default/resources/inspector
.
Consider building with the GN flag debug_devtools=true
to symlink to the original unminified source.
Run Chrome with DevTools frontend bundled:
out/Default/chrome
Test are available by running scripts in third_party/devtools-frontend/src/scripts/test/
.
After building content shell, we can also run layout tests that are relevant for DevTools frontend:
autoninja -C out/Default content_shell
third_party/blink/tools/run_web_tests.py http/tests/devtools
Usual steps for creating a change work out of the box, when executed in third_party/devtools-frontend/src/
.
Please refer to the overview document. The current test status can be seen at the test waterfall.
- DevTools documentation: devtools.chrome.com
- Debugging protocol docs and Chrome Debugging Protocol Viewer
- awesome-chrome-devtools: recommended tools and resources
- Contributing to DevTools: bit.ly/devtools-contribution-guide
- Contributing To Chrome DevTools Protocol: docs.google.com
- DevTools Design Review Guidelines: DESGN_GUIDELINES.MD
Merge request/approval is handled by Chromium Release Managers. DevTools follows The Zen of Merge Requests. In exceptional cases please get in touch with [email protected].
Step-by-step guide on how to merge:
- Request and receive approval to merge
- Backmerges are done to the chromium/xxxx (e.g. chromium/3979) branch respectively on the DevTools frontend repo
- Use Omahaproxy to find out what branch a major Chromium version has (column true_branch). Open the to-be-merged commit in Gerrit e.g. Example
- Click hamburger menu on the top right and select Cherry Pick
- Select branch to merge to e.g. chromium/3968
- Cherry Pick CL is created e.g. Example
- Get it reviewed if necessary
- Click hamburger menu on the cherry pick CL and select Submit
- Done
Formats all code using clang-format.
Runs all static analysis checks on DevTools code.
DevTools frontend repository is mirrored on GitHub.
DevTools frontend is also available on NPM as the chrome-devtools-frontend package. It's not currently available via CJS or ES2015 modules, so consuming this package in other tools may require some effort.
The version number of the npm package (e.g. 1.0.373466
) refers to the Chromium commit position of latest frontend git commit. It's incremented with every Chromium commit, however the package is updated roughly daily.
- All devtools commits: View the log or follow @DevToolsCommits on Twitter
- All open DevTools tickets on crbug.com
- File a new DevTools ticket: new.crbug.com
- Code reviews mailing list: [email protected]
- @ChromeDevTools on Twitter
- Chrome DevTools mailing list: groups.google.com/forum/google-chrome-developer-tools