header, there are examples of [similar approaches](https://developers.google.com/youtube/v3/guides/using_resumable_upload_protocol) in APIs with heavy use.
| GET | `/v2/<name>/blobs/<digest>` | Blob | Retrieve the blob from the registry identified by `digest`. A `HEAD` request can also be issued to this endpoint to obtain resource information without receiving all data. |
| POST | `/v2/<name>/blobs/uploads/` | Intiate Blob Upload | Initiate a resumable blob upload. If successful, an upload location will be provided to complete the upload. Optionally, if the `digest` parameter is present, the request body will be used to complete the upload in a single request. |
| GET | `/v2/<name>/blobs/uploads/<uuid>` | Blob Upload | Retrieve status of upload identified by `uuid`. The primary purpose of this endpoint is to resolve the current status of a resumable upload. |
| PATCH | `/v2/<name>/blobs/uploads/<uuid>` | Blob Upload | Upload a chunk of data for the specified upload. |
| PUT | `/v2/<name>/blobs/uploads/<uuid>` | Blob Upload | Complete the upload specified by `uuid`, optionally appending the body as the final chunk. |
| DELETE | `/v2/<name>/blobs/uploads/<uuid>` | Blob Upload | Cancel outstanding upload processes, releasing associated resources. If this is not called, the unfinished uploads will eventually timeout. |
The detail for each endpoint is covered in the following sections.
### Errors
The error codes encountered via the API are enumerated in the following table:
|Code|Message|Description|
-------|----|------|------------
`UNKNOWN` | unknown error | Generic error returned when the error does not have an API classification.
`UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status.
`DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest.
`SIZE_INVALID` | provided length did not match content length | When a layer is uploaded, the provided size will be checked against the uploaded content. If they do not match, this error will be returned.
`TAG_INVALID` | manifest tag did not match URI | During a manifest upload, if the tag in the manifest does not match the uri tag, this error will be returned.
`NAME_UNKNOWN` | repository name not known to registry | This is returned if the name used during an operation is unknown to the registry.
`MANIFEST_UNKNOWN` | manifest unknown | This error is returned when the manifest, identified by name and tag is unknown to the repository.
`MANIFEST_INVALID` | manifest invalid | During upload, manifests undergo several checks ensuring validity. If those checks fail, this error may be returned, unless a more specific error is included. The detail will contain information the failed validation.
`MANIFEST_UNVERIFIED` | manifest failed signature verification | During manifest upload, if the manifest fails signature verification, this error will be returned.
`BLOB_UNKNOWN` | blob unknown to registry | This error may be returned when a blob is unknown to the registry in a specified repository. This can be returned with a standard get or if a manifest references an unknown layer during upload.
`BLOB_UPLOAD_UNKNOWN` | blob upload unknown to registry | If a blob upload has been cancelled or was never started, this error code may be returned.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
The client does not have access to the repository.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
| `TAG_INVALID` | manifest tag did not match URI | During a manifest upload, if the tag in the manifest does not match the uri tag, this error will be returned. |
The client does not have access to the repository.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
| `TAG_INVALID` | manifest tag did not match URI | During a manifest upload, if the tag in the manifest does not match the uri tag, this error will be returned. |
| `MANIFEST_INVALID` | manifest invalid | During upload, manifests undergo several checks ensuring validity. If those checks fail, this error may be returned, unless a more specific error is included. The detail will contain information the failed validation. |
| `MANIFEST_UNVERIFIED` | manifest failed signature verification | During manifest upload, if the manifest fails signature verification, this error will be returned. |
| `BLOB_UNKNOWN` | blob unknown to registry | This error may be returned when a blob is unknown to the registry in a specified repository. This can be returned with a standard get or if a manifest references an unknown layer during upload. |
The client does not have permission to push to the repository.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
One or more layers may be missing during a manifest upload. If so, the missing layers will be enumerated in the error response.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `BLOB_UNKNOWN` | blob unknown to registry | This error may be returned when a blob is unknown to the registry in a specified repository. This can be returned with a standard get or if a manifest references an unknown layer during upload. |
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
| `TAG_INVALID` | manifest tag did not match URI | During a manifest upload, if the tag in the manifest does not match the uri tag, this error will be returned. |
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
The specified `name` or `tag` are unknown to the registry and the delete was unable to proceed. Clients can assume the manifest was already deleted if this response is returned.
Retrieve the blob from the registry identified by `digest`. A `HEAD` request can also be issued to this endpoint to obtain resource information without receiving all data.
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `NAME_UNKNOWN` | repository name not known to registry | This is returned if the name used during an operation is unknown to the registry. |
| `BLOB_UNKNOWN` | blob unknown to registry | This error may be returned when a blob is unknown to the registry in a specified repository. This can be returned with a standard get or if a manifest references an unknown layer during upload. |
This endpoint may also support RFC7233 compliant range requests. Support can be detected by issuing a HEAD request. If the header `Accept-Range: bytes` is returned, range requests can be used to fetch partial content.
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
###### On Failure: Unauthorized
```
401 Unauthorized
WWW-Authenticate: <scheme> realm="<realm>", ..."
Content-Length: <length>
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": "UNAUTHORIZED",
"message": "access to the requested resource is not authorized",
"detail": ...
},
...
]
}
```
The client does not have access to the repository.
The following headers will be returned on the response:
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
###### On Failure: Not Found
```
404 Not Found
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": <errorcode>,
"message": "<errormessage>",
"detail": ...
},
...
]
}
```
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `NAME_UNKNOWN` | repository name not known to registry | This is returned if the name used during an operation is unknown to the registry. |
| `BLOB_UNKNOWN` | blob unknown to registry | This error may be returned when a blob is unknown to the registry in a specified repository. This can be returned with a standard get or if a manifest references an unknown layer during upload. |
###### On Failure: Requested Range Not Satisfiable
```
416 Requested Range Not Satisfiable
```
The range specification cannot be satisfied for the requested content. This can happen when the range is not formatted correctly or if the range is outside of the valid size of the content.
### Intiate Blob Upload
Initiate a blob upload. This endpoint can be used to create resumable uploads or monolithic uploads.
Initiate a resumable blob upload. If successful, an upload location will be provided to complete the upload. Optionally, if the `digest` parameter is present, the request body will be used to complete the upload in a single request.
|`digest`|query|Digest of uploaded blob. If present, the upload will be completed, in a single request, with contents of the request body as the resulting blob.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
The upload has been created. The `Location` header must be used to complete the upload. The response should be identical to a `GET` request on the contents of the returned `Location` header.
The following headers will be returned with the response:
|`Content-Length`|The `Content-Length` header must be zero and the body must be empty.|
|`Location`|The location of the created upload. Clients should use the contents verbatim to complete the upload, adding parameters where required.|
|`Range`|Range header indicating the progress of the upload. When starting an upload, it will return an empty range, since no content has been received.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
Interact with blob uploads. Clients should never assemble URLs for this endpoint and should only take it through the `Location` header on related API requests. The `Location` header and its parameters should be preserved by clients, using the latest value returned via upload related API calls.
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
###### On Failure: Not Found
```
404 Not Found
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": <errorcode>,
"message": "<errormessage>",
"detail": ...
},
...
]
}
```
The upload is unknown to the registry. The upload must be restarted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `BLOB_UPLOAD_UNKNOWN` | blob upload unknown to registry | If a blob upload has been cancelled or was never started, this error code may be returned. |
|`Content-Range`|header|Range of bytes identifying the desired block of content represented by the body. Start must the end offset retrieved via status check plus one. Note that this is a non-standard use of the `Content-Range` header.|
|`Content-Length`|header|Length of the chunk being uploaded, corresponding the length of the request body.|
|`name`|path|Name of the target repository.|
|`uuid`|path|A uuid identifying the upload. This field can accept almost anything.|
The chunk of data has been accepted and the current progress is available in the range header. The updated upload location is available in the `Location` header.
|`Location`|The location of the upload. Clients should assume this changes after each request. Clients should use the contents verbatim to complete the upload, adding parameters where required.|
There was an error processing the upload and it must be restarted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
###### On Failure: Not Found
```
404 Not Found
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": <errorcode>,
"message": "<errormessage>",
"detail": ...
},
...
]
}
```
The upload is unknown to the registry. The upload must be restarted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `BLOB_UPLOAD_UNKNOWN` | blob upload unknown to registry | If a blob upload has been cancelled or was never started, this error code may be returned. |
###### On Failure: Requested Range Not Satisfiable
Complete the upload, providing the _final_ chunk of data, if necessary. This method may take a body with all the data. If the `Content-Range` header is specified, it may include the final chunk. A request without a body will just complete the upload with previously uploaded content.
|`Content-Range`|header|Range of bytes identifying the block of content represented by the body. Start must the end offset retrieved via status check plus one. Note that this is a non-standard use of the `Content-Range` header. May be omitted if no data is provided.|
|`Content-Length`|header|Length of the chunk being uploaded, corresponding to the length of the request body. May be zero if no data is provided.|
|`Content-Range`|Range of bytes identifying the desired block of content represented by the body. Start must match the end of offset retrieved via status check. Note that this is a non-standard use of the `Content-Range` header.|
|`Content-Length`|Length of the chunk being uploaded, corresponding the length of the request body.|
There was an error processing the upload and it must be restarted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `DIGEST_INVALID` | provided digest did not match uploaded content | When a blob is uploaded, the registry will check that the content matches the digest provided by the client. The error may include a detail structure with the key "digest", including the invalid digest string. This error may also be returned when a manifest includes an invalid layer digest. |
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
###### On Failure: Not Found
```
404 Not Found
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": <errorcode>,
"message": "<errormessage>",
"detail": ...
},
...
]
}
```
The upload is unknown to the registry. The upload must be restarted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `BLOB_UPLOAD_UNKNOWN` | blob upload unknown to registry | If a blob upload has been cancelled or was never started, this error code may be returned. |
###### On Failure: Requested Range Not Satisfiable
```
416 Requested Range Not Satisfiable
Location: /v2/<name>/blobs/uploads/<uuid>
Range: 0-<offset>
```
The `Content-Range` specification cannot be accepted, either because it does not overlap with the current progress or it is invalid. The contents of the `Range` header may be used to resolve the condition.
The following headers will be returned on the response:
|Name|Description|
|----|-----------|
|`Location`|The location of the upload. Clients should assume this changes after each request. Clients should use the contents verbatim to complete the upload, adding parameters where required.|
|`Range`|Range indicating the current progress of the upload.|
|`Content-Length`|Length of the JSON error response body.|
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `UNAUTHORIZED` | access to the requested resource is not authorized | The access controller denied access for the operation on a resource. Often this will be accompanied by a 401 Unauthorized response status. |
###### On Failure: Not Found
```
404 Not Found
Content-Type: application/json; charset=utf-8
{
"errors:" [
{
"code": <errorcode>,
"message": "<errormessage>",
"detail": ...
},
...
]
}
```
The upload is unknown to the registry. The client may ignore this error and assume the upload has been deleted.
The error codes that may be included in the response body are enumerated below:
|Code|Message|Description|
-------|----|------|------------
| `BLOB_UPLOAD_UNKNOWN` | blob upload unknown to registry | If a blob upload has been cancelled or was never started, this error code may be returned. |