### Wstrzykiwanie Zależności

FastAPI zawiera niezwykle łatwy w użyciu, ale niezwykle potężny system <abbr title='Po angielsku: Dependency Injection. Znane również jako "components", "resources", "services", "providers"'><strong>Wstrzykiwania Zależności</strong></abbr>.

* Nawet zależności mogą mieć zależności, tworząc hierarchię lub **"graf" zależności**.

    * The cache can be disabled per dependency declaration, using `use_cache=False` as in `Depends(your_dependency, use_cache=False)`.
    * Updated docs at: [Using the same dependency multiple times](https://fastapi.tiangolo.com/tutorial/dependencies/sub-dependencies/#using-the-same-dependency-multiple-times).
    * PR [#292](https://github.com/tiangolo/fastapi/pull/292).

## Dependabot PRs

Dependabot will create PRs to update dependencies for several things, and those PRs all look similar, but some are way more delicate than others.

* If the PR is for a direct dependency, so, Dependabot is modifying `pyproject.toml`, **don't merge it**. 😱 Let me check it first. There's a good chance that some additional tweaks or updates are needed.

    Note over dep: Run code up to yield
    opt raise Exception
        dep -->> handler: Raise Exception
        handler -->> client: HTTP error response
    end
    dep ->> operation: Run dependency, e.g. DB session
    opt raise
        operation -->> dep: Raise Exception (e.g. HTTPException)
        opt handle
            dep -->> dep: Can catch exception, raise a new HTTPException, raise other exception

 *       APIs are offered that don't).
 *   <li>Can't be passed directly to methods that expect {@code long[]} (though the most common
 *       utilities do have replacements here).
 *   <li>Dependency on {@code com.google.common} / Guava.
 * </ul>
 *
 * <p>Advantages compared to {@link com.google.common.collect.ImmutableList ImmutableList}{@code
 * <Long>}:
 *
 * <ul>

 *       APIs are offered that don't).
 *   <li>Can't be passed directly to methods that expect {@code int[]} (though the most common
 *       utilities do have replacements here).
 *   <li>Dependency on {@code com.google.common} / Guava.
 * </ul>
 *
 * <p>Advantages compared to {@link com.google.common.collect.ImmutableList ImmutableList}{@code
 * <Integer>}:
 *
 * <ul>

            } catch (ArtifactMetadataRetrievalException e) {
                ArtifactResolutionException are = new ArtifactResolutionException(
                        "Unable to get dependency information for " + rootArtifact.getId() + ": " + e.getMessage(),
                        rootArtifact,
                        metadataRequest.getRemoteRepositories(),
                        e);

```console
$ pip install pyjwt

---> 100%
```

</div>

/// info

If you are planning to use digital signature algorithms like RSA or ECDSA, you should install the cryptography library dependency `pyjwt[crypto]`.

You can read more about it in the <a href="https://pyjwt.readthedocs.io/en/latest/installation.html" class="external-link" target="_blank">PyJWT Installation docs</a>.

///

## Password hashing

	if atEOF {
		return len(data), dropCR(data), nil
	}
	// Request more data.
	return 0, nil, nil
}

// isSpace reports whether the character is a Unicode white space character.
// We avoid dependency on the unicode package, but check validity of the implementation
// in the tests.
func isSpace(r rune) bool {
	if r <= '\u00FF' {
		// Obvious ASCII ones: \t through \r plus space. Plus two Latin-1 oddballs.

                  {}, false);
}

TEST_F(CApiFunctionTest, ControlDependency) {
  /*
   *                  |  |    scalar
   *                  |  |    .
   *                  v  v   . <---- control dependency
   *                  add < -
   *                   |
   *                   v
   */
  // Define
  TF_Operation* feed1 = Placeholder(func_graph_, s_, "feed1");