## Architecture Standards

**Experimental!**

We'd like to capture our architectural decisions about the build tool as [Architectural Decision Records (ADRs)](https://adr.github.io/).
For now we just have this global repository of ADRs.
If we see fit, we can break these out to per-platform ones, or keep a hybrid approach to having global and platform-specific ADSs.

Our aim is to keep the process lightweight and approachable.

    return PlainTextResponse(message, status_code=400)


@app.get("/items/{item_id}")
async def read_item(item_id: int):
    if item_id == 3:
        raise HTTPException(status_code=418, detail="Nope! I don't like 3.")

func (s *Scanner) MaxTokenSize(n int) {
	if n < utf8.UTFMax || n > 1e9 {
		panic("bad max token size")
	}
	if n < len(s.buf) {
		s.buf = make([]byte, n)
	}
	s.maxTokenSize = n
}

// ErrOrEOF is like Err, but returns EOF. Used to test a corner case.
func (s *Scanner) ErrOrEOF() error {
	return s.err

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.lifecycle.internal;

import org.apache.maven.execution.MavenSession;

/**
 * Starts the build life cycle
 *
 */
public interface LifecycleStarter {

    void execute(MavenSession session);

    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-di</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-jline</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-logging</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>

Here the query parameter `needy` is a required query parameter of type `str`.

If you open in your browser a URL like:

```
http://127.0.0.1:8000/items/foo-item
```

...without adding the required parameter `needy`, you will see an error like:

```JSON
{
  "detail": [
    {
      "type": "missing",
      "loc": [
        "query",
        "needy"
      ],

In this case, the database session would be held until the response is finished being sent, but if you don't use it, then it wouldn't be necessary to hold it.

Here's how it could look like:

{* ../../docs_src/dependencies/tutorial013_an_py310.py *}

#### Identity information 

This is an inappropriate use of lazy types:

```groovy
class Example {
    Provider<String> getPath() {
        return project.provider(() -> path)
    }
}
```

Like above, this is an immutable part of the identity of the domain object and cannot be changed.

### Properties in entirely new classes

But you would get the same editor support with <a href="https://www.jetbrains.com/pycharm/" class="external-link" target="_blank">PyCharm</a> and most of the other Python editors:

<img src="/img/tutorial/body/image05.png">

/// tip

///

## Dependencies errors and return values { #dependencies-errors-and-return-values }

You can use the same dependency *functions* you use normally.

### Dependency requirements { #dependency-requirements }

They can declare request requirements (like headers) or other sub-dependencies: