### Dependencies { #dependencies }

The same applies for [dependencies](tutorial/dependencies/index.md){.internal-link target=_blank}. If a dependency is a standard `def` function instead of `async def`, it is run in the external threadpool.

### Sub-dependencies { #sub-dependencies }

- Automatic in-memory or on-disk caching of request/response bodies
- Synchronous and asynchronous (callback) execution
- Minimal dependencies (only Apache Commons IO)

## Installation

### Maven

Add the dependency to your `pom.xml` (replace `x.y.z` with the latest version):

```xml
<dependency>
  <groupId>org.codelibs</groupId>

  define for each {{{../../api/maven-api-model/maven.html#class_dependency}dependency type}} information on the artifact
  (classifier, extension, language) and how to manage it as dependency (add to classpath, include dependencies).

  They are replaced in Maven 4 with Maven 4 API Core's {{{../../api/maven-api-core/apidocs/org/apache/maven/api/Type.html}Dependency Types}},

  <description>Model for Maven POM (Project Object Model)</description>

  <properties>
    <!-- in: ModelMerger -->
    <checkstyle.violation.ignore>FileLength</checkstyle.violation.ignore>
  </properties>

  <dependencies>
    <dependency>
      <groupId>org.apache.maven</groupId>
      <artifactId>maven-api-model</artifactId>
    </dependency>
    <dependency>
      <groupId>org.apache.maven</groupId>

import org.apache.maven.execution.MavenSession;
import org.apache.maven.execution.ProjectDependencyGraph;
import org.apache.maven.model.building.Result;

/**
 * Builds the {@link ProjectDependencyGraph inter-dependencies graph} between projects in the reactor.
 *
 * @since 3.0-alpha
 */
public interface GraphBuilder {
    String HINT = "graphBuilder";

    Result<? extends ProjectDependencyGraph> build(MavenSession session);

async def verify_key(x_key: Annotated[str, Header()]):
    if x_key != "fake-super-secret-key":
        raise HTTPException(status_code=400, detail="X-Key header invalid")
    return x_key


app = FastAPI(dependencies=[Depends(verify_token), Depends(verify_key)])


@app.get("/items/")
async def read_items():
    return [{"item": "Portal Gun"}, {"item": "Plumbus"}]


@app.get("/users/")
async def read_users():

    - [Container Images](#container-images)
  - [Changelog since v1.29.14](#changelog-since-v12914)
  - [Changes by Kind](#changes-by-kind)
    - [Other (Cleanup or Flake)](#other-cleanup-or-flake)
  - [Dependencies](#dependencies)
    - [Added](#added)
    - [Changed](#changed)
    - [Removed](#removed)
- [v1.29.14](#v12914)
  - [Downloads for v1.29.14](#downloads-for-v12914)
    - [Source Code](#source-code-1)

                                    phase(RESOURCES),
                                    phase(COMPILE, after(SOURCES), dependencies(SCOPE_COMPILE, READY)),
                                    phase(READY, after(COMPILE), after(RESOURCES)),
                                    phase(PACKAGE, after(READY), dependencies(SCOPE_RUNTIME, PACKAGE))),
                            phase(
                                    VERIFY,

    @Override
    public void artifactDescriptorInvalid(RepositoryEvent event) {
        // The exception stack trace is not really interesting here
        logger.warn(
                "The POM for {} is invalid, transitive dependencies (if any) will not be available: {}",
                event.getArtifact(),
                event.getException().getMessage());
    }

    @Override
    public void artifactDescriptorMissing(RepositoryEvent event) {

        PlexusConfiguration[] dependencyConfigurations =
                c.getChild("dependencies").getChildren("dependency");

        List<ComponentDependency> dependencies = new ArrayList<>();

        for (PlexusConfiguration d : dependencyConfigurations) {
            dependencies.add(extractComponentDependency(d));
        }
        return dependencies;
    }