Setting up Codecov in Badgeyay


BadgeYaY already has Travis CI and Codacy to test code quality and Pull Request but there was no support for testing Code Coverage in repository against every Pull Request. So I decided to go with setting up Codecov to test the code coverage.

In this blog post, I’ll be discussing how I have set up codecov in BadgeYaY in my Pull Request.

First, let’s understand what is codecov and why do we need it. For that we have to first understand what is code coverage then we will move on to how to add Codecov with help of Travis CI .

Let’s get started and understand it step by step.

What is Code Coverage ?

Code coverage is a measurement used to express which lines of code were executed by a test suite. We use three primary terms to describe each lines executed.

  • hit indicates that the source code was executed by the test suite.
  • partial indicates that the source code was not fully executed by the test suite; there are remaining branches that were not executed.
  • miss indicates that the source code was not executed by the test suite.

Coverage is the ratio of hits / (hit + partial + miss). A code base that has 5 lines executed by tests out of 12 total lines will receive a coverage ratio of 41% . In BadgeYaY , Code Coverage is 100%.

How CodeCov helps in Code Coverage ?

Codecov focuses on integration and promoting healthy pull requests. Codecov delivers <<<or “injects”>>> coverage metrics directly into the modern workflow to promote more code coverage, especially in pull requests where new features and bug fixes commonly occur.

I am listing down top 5 Codecov Features:

We can change the configuration of how Codecov processes reports and expresses coverage information. Let’s see how we configure it according to BadgeYaY by integrating it with Travis CI.

Now generally, the codecov works better with Travis CI. With the one line

 bash <(curl -s


the code coverage can now be easily reported.

Add a script for testing:

"scripts": {
   - nosetests app/tests/ -v --with-coverage

Here is a particular example of travis.yml from the project repository of BadgeYaY:

- python app/ >> log.txt 2>&1  &
- nosetts app/tests/ -v --with-coverage
- python3 -m pyflakes

- bash <(curl -s


Let’s have a look at Codecov.yml to check exact configuration that I have used for BadgeYaY.

  # yes: will delay sending notifications until all ci is finished
    require_ci_to_pass: yes

  # how many decimal places to display in the UI: 0 <= value <= 4
  precision: 2
  # how coverage is rounded: down/up/nearest
  round: down 
  # custom range of coverage colors from red -> yellow -> green 
  range: "70...100"

     # measuring the overall project coverage
    project: yes
     # pull requests only: this commit status will measure the
       entire pull requests Coverage Diff. Checking if the lines
       adjusted are covered at least X%.
    patch: yes
     # if there are any unexpected changes in coverage
    changes: no


  layout: "reach, diff, flags, files, footer"
  behavior: default
  require_changes: no


Now when anyone makes a Pull Request to BadgeYaY, Codecov will analyze the Pull Request according to above configuration and generate a Report showing the code coverage of that Pull Request.


Below is the screenshot of all test passing in BadgeYaY repository

This is how we setup codecov in BadgeYaY repository. And like this way, it can be set up in other repositories as well.

The related PR of this work is

Resources :

  • CodeCov Documentation – Link

Deployment terms in Open Event Frontend

In Open Event Frontend, once a pull request is opened, we see some tests running on for the specific pull request like ‘Codacy’, ‘Codecov’, ‘Travis’, etc. New contributors eventually get confused what the tests are about. So this blog would be a walkthrough to these terms that we use and what they mean about the PR.

Travis: Everytime you make a pull request, you will see this test running and in some time giving the output whether the test passed or failed. Travis is the continuous integration test that we are using to test that the changes that the pull request you proposed does not break any other things. Sometimes you will see the following message which indicates that your changes is breaking something else which is not intended.

Thus, by looking at the Travis logs, you can see where the changes proposed in the pull request are breaking things. Thus, you can go ahead and correct the code and push again to run the Travis build until it passes.

Codacy: Codacy is being used to check the code style, duplication, complexity and coverage, etc. When you create a pull request or update the pull request, this test runs which checks whether the code followed certain style guide or if there is duplication in code, etc. For instance let’s say if your code has a html page in which a tag has an attribute which is left undefined. Then codacy will be throwing error failing the tests. Thus you need to see the logs and go correct the bug in code. The following message shows that the codacy test has passed.


Codecov is a code coverage test which indicates how much of the code change that is proposed in the pull request is actually executed. Consider out of the 100 lines of code that you wrote, only 80 lines is being actually executed and rest is not, then the code coverage decreases. The following indicates the codecov report.

Thus, it can be seen that which files are affected by what percent.


The surge link is nothing but the deployment link of the changes in your pull request.

Thus, checking the link manually, we can test the behavior of the app in terms of UI/UX or the other features that the pull request adds.




Setting up Codecov in Susper repository hosted on Github

In this blog post, I’ll be discussing how we setup codecov in Susper.

  • What is Codecov and in what projects it is being used in FOSSASIA?

Codecov is a famous code coverage tool. It can be easily integrated with the services like Travis CI. Codecov also provides more features with the services like Docker.

Projects in FOSSASIA like Open Event Orga Server, Loklak search, Open Event Web App uses Codecov. Recently, in the Susper project also the code coverage tool has been configured.

  • How we setup Codecov in our project repository hosted on Github?

The simplest way to setup Codecov in a project repository is by installing using the terminal command:

npm install --save-dev

Susper works on tech-stack Angular 2 (we have recently upgraded it to Angular v4.1.3) recently. Angular comes with Karma and Jasmine for testing purpose. There are many repositories of FOSSASIA in which Codecov has been configured like this. But with, Angular this case is a little bit tricky. So, using alone:

bash <(curl -s

won’t generate code coverage because of the presence of Karma and Jasmine. It will require two packages: istanbul as coverage reporter and jasmine as html reporter. I have discussed them below.

Install these two packages:

  • Karma-coverage-istanbul-reporter
  • npm install karma-coverage-istanbul-reporter --save-dev
  • Karma-jasmine html reporter
  • npm install karma-jasmine-html-reporter --save-dev

    After installing the, the package.json will be updated as follows:

  • "devDependencies": {
      "codecov": "^2.2.0",
      "karma-coverage-istanbul-reporter": "^1.3.0",
      "karma-jasmine-html-reporter": "^0.2.2",

    Add a script for testing:

  • "scripts": {
       "test": "ng test --single-run --code-coverage --reporters=coverage-istanbul"

    Now generally, the codecov works better with Travis CI. With the one line bash <(curl -s the code coverage can now be easily reported.

Here is a particular example of travis.yml from the project repository of Susper:

 - ng test --single-run --code-coverage --reporters=coverage-istanbul
 - ng lint
 - bash <(curl -s
 - bash ./

Update karma.config.js as well:

Module.exports = function (config) {
    plugins: [
    preprocessors: {
      'src/app/**/*.js': ['coverage']
    client {
      clearContext: false
    coverageIstanbulReporter: {
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    reporters: config.angularCli && config.angularCli.codeCoverage
      ? ['progress', 'coverage-istanbul'],
      : ['progress', 'kjhtml'],

This karma.config.js is an example from the Susper project. Find out more here:
This is how we setup codecov in Susper repository. And like this way, it can be set up in other repositories as well which supports Angular 2 or 4 as tech stack.

Getting code coverage in a Nodejs project using Travis and CodeCov

We had set up unit tests on the webapp generator using mocha and chai, as I had blogged before.

But we also need to get coverage reports for each code commit and the overall state of the repo.

Since it is hosted on Github, Travis comes to our rescue. As you can see from our .travis.yml file, we already had Travis running to check for builds, and deploying to heroku.

Now to enable Codecov, simply go to and enable your repository (You have to login with Github so see your Github repos) .

Once you do it, your dashboard should be visible like this

We use istanbul to get codecoverage. To try it out just use

istanbul cover _mocha

On the root of your project (where the /test/ folder is ) . That should generate a folder called coverage or lcov. Codecov can read lcov reports. They have provided a bash file which can be run to automatically upload coverage reports. You can run it like this –

bash <(curl -s

Now go back to your codecov dashboard, and your coverage report should show up.

Screenshot from 2016-08-29 21-23-00

If all is well, we can integrate this with travis so that it happens on every code push. Add this to your travis.yml file.

  - istanbul cover _mocha
- bash <(curl -s

This will ensure that on each push, we run coverage first. And if it is successful, we push the result to codecov.

We can see coverage file by file like this

Screenshot from 2016-08-29 21-23-35

And we can see coverage line by line in a file like this

Screenshot from 2016-08-29 21-26-55