Benchmark: fetch and Jason parsing

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

let url = URL.createObjectURL(new Blob([JSON.stringify({a:3,b:3,c:3,n:6,baeij:2,ifjq3:[1,2,3,4,5]})],{type:'application/json'}))
function finish() {
deferred.resolve()
}
function auto(j) {
 j.json().then(finish)
}
function parse(j) {
j.text().then(JSON.parse).then(finish)
}

Tests:

fetch.json()
fetch(url).then(auto)
fetch+json.parse
fetch(url).then(parse)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
fetch.json()
fetch+json.parse

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one month ago)

User agent: Mozilla/5.0 (X11; CrOS x86_64 14541.0.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser/OS: Chrome 132 on Chrome OS 14541.0.0

View result in a separate tab

Test name	Executions per second
fetch.json()	1448.3 Ops/sec
fetch+json.parse	1373.3 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):

LLMs can make mistakes. Check important info.

The benchmark you've provided compares two different approaches to fetching JSON data and processing it in JavaScript. The two methods being tested are:

1. **Using the `Response.json()` method** directly on the Fetch API response.
2. **Using `Response.text()` followed by `JSON.parse()`** to handle the JSON data.

### Description of the Benchmark

1. **Benchmark Definition:**
   - **`fetch(url).then(auto)`**: This test case utilizes the built-in `.json()` method of the Fetch API. The `auto` function is called when the response is successfully parsed into a JSON object. This is considered a more straightforward method for extracting JSON data from a response.
   
   - **`fetch(url).then(parse)`**: In this test case, the response is first converted to text with the `.text()` method. Then, the text is manually parsed using `JSON.parse()`, capturing the invoking function in the `parse` function.

### Pros and Cons of Each Approach

#### Using `Response.json()`

**Pros:**
- **Simplicity**: This approach is more concise and easier to read. The API is designed specifically for handling JSON, reducing the need for additional parsing steps.
- **Error Handling**: The `.json()` method automatically handles any issues that might arise with malformed JSON during parsing without requiring additional checks for proper formatting.
- **Performance**: In many cases, this method is optimized and may have better performance in terms of speed due to potential internal optimizations within the Fetch API implementation.

**Cons:**
- **Limited to JSON**: The method is specifically designed for JSON parsing, meaning it cannot handle other content types without conversion to text first.
- **Browser Support**: All modern browsers support this function, but older browsers may need polyfills or alternatives.

#### Using `Response.text()` and `JSON.parse()`

**Pros:**
- **Flexibility**: This method can handle any type of response text, allowing you to first retrieve the raw text and decide how to process it.
- **Control**: Developers have more control over the parsing process, allowing for custom error handling and logic based on the content returned.

**Cons:**
- **More Verbose**: This method requires additional lines of code, increasing complexity compared to the simpler `.json()` method.
- **Manual Error Handling**: It involves the need for manual error checking when parsing, increasing the potential for bugs if not handled properly.

### Performance Results

The benchmark results indicated that the `fetch.url().then(auto)` (using `.json()`) had a higher execution rate of approximately **1448.30 executions per second**, while the `fetch(url).then(parse)` (using `JSON.parse()`) achieved around **1373.35 executions per second**. This suggests that using the `.json()` method is generally more efficient in this specific test.

### Other Considerations

- **Browser Compatibility**: Both methods are widely supported in modern browsers; however, considerations might need to be made for very old versions where `Response.json()` might not be available.
- **Use Cases**: For applications primarily dealing with JSON APIs, the `.json()` method is usually preferred due to its simplicity. The manual method could be more appropriate for APIs returning mixed content types.

### Alternatives

1. **Axios**: A popular library for making HTTP requests in JavaScript that simplifies the fetching and parsing of JSON data. It automatically converts responses to JSON, similar to the Fetch API's `.json()`, but also offers additional features like interceptors.
   
2. **jQuery AJAX**: While not as common in modern web development, jQuery provides powerful AJAX utilities that can simplify fetching and manipulating remote data, though it adds an additional dependency.

3. **Fetch with Async/Await**: Instead of using `.then()`, developers can also utilize `async/await` syntax for more readable asynchronous code for both methods mentioned.

In summary, while both methods are functional, using `Response.json()` generally offers a more efficient and cleaner approach when working specifically with JSON data.

Related benchmarks:

fetch and Jason parsing (version: 1)

Comparing performance of: fetch.json() vs fetch+json.parse

Created: one month ago by: Guest

Jump to the latest result

fetch.json()

fetch+json.parse

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated one month ago):