PWMetrics

Progressive web metrics at your fingertipz. 💅

CLI tool and lib to gather performance metrics via Lighthouse.

Documentation on these metrics in the works. If you hit bugs in the metrics collection, report at Lighthouse issues. How to use article

Install

$ yarn global add pwmetrics
# or
$ yarn add --dev pwmetrics

CLI Usage

$ pwmetrics <url><flags>
pwmetrics http://example.com/
# --runs=n Does n runs (eg. 3, 5), and reports the median run's numbers.# Median run selected by run with the median TTI.
pwmetrics http://example.com/ --runs=3
# --json Reports json details to stdout.
pwmetrics http://example.com/ --json
# returns...# {runs: [{# "timings": [# {# "name": "First Contentful Paint",# "value": 289.642# },# {# "name": "First Meaningful Paint",# "value": 289.6# },# ...# --output-path File path to save results.
pwmetrics http://example.com/ --output-path='pathToFile/file.json'# --config Provide configuration (defaults to `package.json`). See _Defining config_ below.
pwmetrics --config=pwmetrics-config.js
# --submit Submit results to Google Sheets. See _Defining submit_ below.
pwmetrics --submit
# --upload Upload Lighthouse traces to Google Drive. See _Defining upload_ below.
pwmetrics --upload
# --view View Lighthouse traces, which were uploaded to Google Drive, in DevTools. See _Defining view_ below.
pwmetrics --view
#### CLI options useful for CI### --expectations Assert metrics results against provides values. See _Defining expectations_ below.
pwmetrics --expectations
# --fail-on-error Exit PWMetrics with an error status code after the first unfilled expectation.
pwmetrics --fail-on-error

Defining config

# run pwmetrics with config in package.json
pwmetrics --config

package.json

...
"pwmetrics": {
"url": "http://example.com/",
// other configuration options
}
...

# run pwmetrics with config in pwmetrics-config.js
pwmetrics --config=pwmetrics-config.js

pwmetrics-config.js

module.exports={url: 'http://example.com/',// other configuration options. Read _All available configuration options_}

All available configuration options

pwmetrics-config.js

constMETRICS=require('pwmetrics/lib/metrics');constlhConfig=require('./lr-desktop-config');// config file for lighthousemodule.exports={url: 'http://example.com/',testName: 'homepage test',// not required, name of the test suiteflags: {// AKA feature flagsruns: 3,// number or runssubmit: true,// turn on submitting to Google Sheetsupload: true,// turn on uploading to Google Driveview: true,// open uploaded traces to Google Drive in DevToolsexpectations: true,// turn on assertion metrics results against provides valuesjson: true,// not required, set to true if you want json outputoutputPath: 'stdout',// not required, only needed if you have specified json output, can be "stdout" or a pathlaunchChrome: false,// don't launch chrome. Useful when puppeteer is used to loginchromePath: '/Applications/Google\ Chrome\ Canary.app/Contents/MacOS/Google\ Chrome\ Canary',//optional path to specific Chrome locationchromeFlags: '',// custom flags to pass to Chrome. For a full list of flags, see http://peter.sh/experiments/chromium-command-line-switches/.config: lhConfig,// replaces /lib/perf-config with the selected config for lighthouse// Note: pwmetrics supports all flags from LighthouseshowOutput: true,// not required, set to false for pwmetrics not output any console.log messagesfailOnError: false,// not required, set to true if you want to fail the process on expectations errorsjunitReporterOutputPath: '/reports',// not required, set a directory if you want a junit report of the expectations},expectations: {// these expectations values are examples, for your cases set your own// it's not required to use all metrics, you can use just a few of them// Read _Available metrics_ where all keys are defined[METRICS.TTFCP]: {warn: '>=1500',error: '>=2000'},[METRICS.TTFMP]: {warn: '>=2000',error: '>=3000'},[METRICS.TTI]: {
...
},[METRICS.TTFCPUIDLE]: {
...
},[METRICS.SI]: {
...
},},sheets: {type: 'GOOGLE_SHEETS',// sheets service type. Available types: GOOGLE_SHEETSoptions: {spreadsheetId: 'sheet_id',tableName: 'data',uploadMedian: false// not required, set to true if you want to upload only the median run}},clientSecret: {// Data object. Can be get// either// by (using everything in step 1 here)[https://developers.google.com/sheets/api/quickstart/nodejs#step_1_turn_on_the_api_name]//// example format://// installed: {// client_id: "sample_client_id",// project_id: "sample_project_id",// auth_uri: "https://accounts.google.com/o/oauth2/auth",// token_uri: "https://accounts.google.com/o/oauth2/token",// auth_provider_x509_cert_url: "https://www.googleapis.com/oauth2/v1/certs",// client_secret: "sample_client_secret",// redirect_uris: [// "url",// "http://localhost"// ]// }//// or// by (using everything in step 1 here)[https://developers.google.com/drive/v3/web/quickstart/nodejs]}}

Defining expectations

Recipes for using with CI

# run pwmetrics with config in package.json
pwmetrics --expectations

package.json

...
"pwmetrics": {
"url": "http://example.com/",
"expectations": {
...
}
}
...

# run pwmetrics with config in pwmetrics-config.js
pwmetrics --expectations --config=pwmetrics-config.js

Defining submit

Submit results to Google Sheets

Instructions:

• Copy this spreadsheet.
• Copy the ID of the spreadsheet into the config as value of sheets.options.spreadsheetId property.
• Setup Google Developer project and get credentials. (everything in step 1 here)
• Take a client_secret and put it into the config as value of clientSecret property.

# run pwmetrics with config in package.json
pwmetrics --submit

# run pwmetrics with config in pwmetrics-config.js
pwmetrics --submit --config=pwmetrics-config.js

pwmetrics-config.js

module.exports={'url': 'http://example.com/','sheets': {
...
},'clientSecret': {
...
}}

Defining upload

Upload Lighthouse traces to Google Drive

Instructions:

• Setup Google Developer project and get credentials. (everything in step 1 here)
• Take a client_secret and put it into the config as value of clientSecret property.

# run pwmetrics with config in package.json
pwmetrics --upload

# run pwmetrics with config in pwmetrics-config.js
pwmetrics --upload --config=pwmetrics-config.js

pwmetrics-config.js

module.exports={'url': 'http://example.com/','clientSecret': {
...
}}

View Lighthouse traces in timeline-viewer

Show Lighthouse traces in timeline-viewer.

Required to use upload flag

timeline-viewer - Shareable URLs for your Chrome DevTools Timeline traces.

# run pwmetrics with config in package.json
pwmetrics --upload --view

# run pwmetrics with config in your-own-file.js
pwmetrics --upload --view --config=your-own-file.js

pwmetrics-config.js

module.exports={'url': 'http://example.com/','clientSecret': {
...
}}

Available metrics:

All metrics now are stored in separate constant object located in pwmetrics/lib/metrics/metrics;

// lib/metrics/metrics.ts{METRICS: {TTFCP: 'firstContentfulPaint',TTFMP: 'firstMeaningfulPaint',TTFCPUIDLE: 'firstCPUIdle',TTI: 'interactive',SI: 'speedIndex'}}

Read article Performance metrics. What’s this all about? which is decoding this metrics.

API

constPWMetrics=require('pwmetrics');constoptions={flags: {runs: 3,// number or runssubmit: true,// turn on submitting to Google Sheetsupload: true,// turn on uploading to Google Driveview: true,// open uploaded traces to Google Drive in DevToolsexpectations: true,// turn on assertation metrics results against provides valueschromeFlags: '--headless'// run in headless Chrome}};constpwMetrics=newPWMetrics('http://example.com/',options);// _All available configuration options_ can be used as `options`pwMetrics.start();// returns Promise

Options

Option	Type	Default	Description
flags*	Object	{ runs: 1, submit: false, upload: false, view: false, expectations: false, disableCpuThrottling: false, chromeFlags: '' }	Feature flags
expectations	Object	{}	See Defining expectations above.
sheets	Object	{}	See Defining submit above.
clientSecret	Object	{}	Client secrete data generated by Google API console. To setup Google Developer project and get credentials apply everything in step 1 here.

^*pwmetrics supports all flags from Lighthouse. See here for the complete list.

Recipes

• gulp

License

Apache 2.0. Google Inc.