<p>Postman uses the Chai Assertion Library so familiarize yourself with it.</p>
<h1 id="heading-using-chai-match-assertion">Using Chai Match Assertion</h1>
<p>You can define a format for your response using Regex and the match assertion. Below is an example of a data format for a mysql date.</p>
<h3 id="heading-date-format">Date Format</h3>
<pre><code class="lang-javascript">pm.test(<span class="hljs-string">"Date is correct format"</span>, <span class="hljs-function"><span class="hljs-keyword">function</span>(<span class="hljs-params"></span>) </span>{
            pm.expect(jsonData.date).to.match(<span class="hljs-regexp">/^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}Z$/</span>, <span class="hljs-string">"Date should be 0000-00-00T00:00:00Z not "</span> + jsonData.date);
        });
</code></pre>
<h3 id="heading-multiple-assertions">Multiple Assertions</h3>
<p>When using multiple assertions on a single data point you don't need to create an a new pm.expect. Instead use and and a proper error message. Since a proper error message is there you will know what has happened. </p>
<p>And</p>
<pre><code class="lang-javascript">pm.expect(jsonData.smallsString).to.be.a(<span class="hljs-string">'string'</span>, <span class="hljs-string">'smallsString is not a string'</span>)
     .and.be.lengthOf(<span class="hljs-number">5</span>, <span class="hljs-string">'smallsString is not 5 in length'</span>)
     .and.to.contain(<span class="hljs-string">'den'</span>, <span class="hljs-string">'smallsString does not contain den'</span>)
</code></pre>
<p>See the below Chai Assertion Library link for more on Chai Assertions.</p>
<h1 id="heading-links">Links</h1>
<p><a href="https://postman-quick-reference-guide.readthedocs.io/en/latest/index.html">Postman Quick Reference Guide</a>
<a href="https://www.chaijs.com/api/bdd/">Chai Assertion Library</a>
<a href="https://www.rexegg.com/regex-quickstart.html">Regex Cheat Sheet</a>
<a href="https://www.udemy.com/postman-the-complete-guide/">Postman: The Complete Guide on Udemy</a></p>


Postman uses the Chai Assertion Library so familiarize yourself with it.

# Using Chai Match Assertion
You can define a format for your response using Regex and the match assertion. Below is an example of a data format for a mysql date.

### Date Format

```javascript
pm.test("Date is correct format", function() {
            pm.expect(jsonData.date).to.match(/^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}Z$/, "Date should be 0000-00-00T00:00:00Z not " + jsonData.date);
        });
```
### Multiple Assertions
When using multiple assertions on a single data point you don't need to create an a new pm.expect. Instead use and and a proper error message. Since a proper error message is there you will know what has happened. 

And
```javascript
pm.expect(jsonData.smallsString).to.be.a('string', 'smallsString is not a string')
     .and.be.lengthOf(5, 'smallsString is not 5 in length')
     .and.to.contain('den', 'smallsString does not contain den')
```

See the below Chai Assertion Library link for more on Chai Assertions.

# Links
[Postman Quick Reference Guide](https://postman-quick-reference-guide.readthedocs.io/en/latest/index.html)
[Chai Assertion Library](https://www.chaijs.com/api/bdd/)
[Regex Cheat Sheet](https://www.rexegg.com/regex-quickstart.html)
[Postman: The Complete Guide on Udemy](https://www.udemy.com/postman-the-complete-guide/)

Testing with Postman: Chai Assertions

As the son of a programmer I grew up on computers and have always loved them. Now I work as a Software Development Engineer in Test to write code and test things. I also enjoy my homelab hobby.


Lead QA Engineer and SDET for Ameritas with 9 years of Experience in the QA field.

Ben Weese’s Blog

Ben Weese’s Blog

Testing with Postman: Chai Assertions

Using Chai Match Assertion

Date Format

Multiple Assertions

Links