# Request Body { #request-body }

When you need to send data from a client (let's say, a browser) to your API, you send it as a **request body**.

A **request** body is data sent by the client to your API. A **response** body is the data your API sends to the client.

			if i%4 == 0 {
				m.Lock(id, source)
				acc0 -= 100
				acc1 += 100
				m.Unlock(b.Context())
			} else {
				for i := 0; i < len(data); i += 4 {
					data[i]++
				}
				// Elaborate way to say runtime.Gosched
				// that does not put the goroutine onto global runq.
				go func() {
					c <- true
				}()
				<-c
			}
		}
	})
}

func BenchmarkMutexSpin(b *testing.B) {

You can add custom exception handlers with <a href="https://www.starlette.dev/exceptions/" class="external-link" target="_blank">the same exception utilities from Starlette</a>.

Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

And you want to handle this exception globally with FastAPI.

You could add a custom exception handler with `@app.exception_handler()`:

     * is that in JavaScript, a single quote must be escaped.</p>
     *
     * <p>Example:</p>
     * <pre>
     * input string: He didn't say, "Stop!"
     * output string: He didn't say, \"Stop!\"
     * </pre>
     *
     *
     * @param str  String to escape values in, may be null
     * @return String with escaped values, <code>null</code> if null string input
     */

     * is that in JavaScript, a single quote must be escaped.</p>
     *
     * <p>Example:</p>
     * <pre>
     * input string: He didn't say, "Stop!"
     * output string: He didn't say, \"Stop!\"
     * </pre>
     *
     *
     * @param str  String to escape values in, may be null
     * @return String with escaped values, <code>null</code> if null string input
     */

For example, let's say you have 4 API endpoints (*path operations*):

* `/items/public/`
* `/items/private/`
* `/users/{user_id}/activate`
* `/items/pro/`

To solve that, FastAPI `0.103.0` **added support** for declaring the same old **OpenAPI-specific** `examples` field with the new parameter `openapi_examples`. 🤓

### Summary { #summary }

I used to say I didn't like history that much... and look at me now giving "tech history" lessons. 😅

     *
     * RFC 2388 is rather vague about how one should escape special characters in form-data
     * parameters, and as it turns out Firefox and Chrome actually do rather different things, and
     * both say in their comments that they're not really sure what the right approach is. We go
     * with Chrome's behavior (which also experimentally seems to match what IE does), but if you

- Choice of erasure set size is automatic based on the number of drives available, let's say for example if there are 32 servers and 32 drives which is a total of 1024 drives. In this scenario 16 becomes the erasure set size. This is decided based on the greatest common divisor (GCD) of acceptable erasure set sizes ranging from *4 to 16*.

                             * augment the addresses name's hashCode to distinguish those resolved by
                             * Lmhosts, WINS, or BCAST. Otherwise a failed query from say WINS would
                             * get pulled out of the cache for a BCAST on the same name.
                             */
                            response.addrEntry[0].hostName.srcHashCode = request.addr.hashCode();