Struct Metadata

pub struct Metadata { /* private fields */ }

Metadata contains all the information related to a specific path.

Depending on the context of the requests, the metadata for the same path may vary. For example, two versions of the same path might have different content lengths. Keep in mind that metadata is always tied to the given context and is not a global state.

File Versions

In systems that support versioning, such as AWS S3, the metadata may represent a specific version of a file.

Users can access Metadata::version to retrieve the file’s version, if available. They can also use Metadata::is_current and Metadata::is_deleted to determine whether the metadata corresponds to the latest version or a deleted one.

The all possible combinations of is_current and is_deleted are as follows:

is_current	is_deleted	description
Some(true)	false	The metadata’s associated version is the latest, current version. This is the normal state, indicating that this version is the most up-to-date and accessible version.
Some(true)	true	The metadata’s associated version is the latest, deleted version (Latest Delete Marker or Soft Deleted). This is particularly important in object storage systems like S3. It signifies that this version is the most recent delete marker, indicating the object has been deleted. Subsequent GET requests will return 404 errors unless a specific version ID is provided.
Some(false)	false	The metadata’s associated version is neither the latest version nor deleted. This indicates that this version is a previous version, still accessible by specifying its version ID.
Some(false)	true	The metadata’s associated version is not the latest version and is deleted. This represents a historical version that has been marked for deletion. Users will need to specify the version ID to access it, and accessing it may be subject to specific delete marker behavior (e.g., in S3, it might not return actual data but a specific delete marker response).
None	false	The metadata’s associated file is not deleted, but its version status is either unknown or it is not the latest version. This likely indicates that versioning is not enabled for this file, or versioning information is unavailable.
None	true	The metadata’s associated file is deleted, but its version status is either unknown or it is not the latest version. This typically means the file was deleted without versioning enabled, or its versioning information is unavailable. This may represent an actual data deletion operation rather than an S3 delete marker.

Implementations

impl Metadata

pub fn new(mode: EntryMode) -> Self

Create a new metadata

pub fn mode(&self) -> EntryMode

mode represent this entry’s mode.

pub fn set_mode(&mut self, v: EntryMode) -> &mut Self

Set mode for entry.

pub fn with_mode(self, v: EntryMode) -> Self

Set mode for entry.

pub fn is_file(&self) -> bool

Returns true if this metadata is for a file.

pub fn is_dir(&self) -> bool

Returns true if this metadata is for a directory.

pub fn is_current(&self) -> Option<bool>

Checks whether the metadata corresponds to the most recent version of the file.

This function is particularly useful when working with versioned objects, such as those stored in systems like AWS S3 with versioning enabled. It helps determine if the retrieved metadata represents the current state of the file or an older version.

Refer to docs in Metadata for more information about file versions.

Return Value

The function returns an Option<bool> which can have the following values:

• Some(true): Indicates that the metadata is associated with the latest version of the file. The metadata is current and reflects the most up-to-date state.
• Some(false): Indicates that the metadata is not associated with the latest version of the file. The metadata belongs to an older version, and there might be a more recent version available.
• None: Indicates that the currency of the metadata cannot be determined. This might occur if versioning is not supported or enabled, or if there is insufficient information to ascertain the version status.

pub fn set_is_current(&mut self, is_current: bool) -> &mut Self

Set the is_current status of this entry.

By default, this value will be None. Please avoid using this API if it’s unclear whether the entry is current. Set it to true if it is known to be the latest; otherwise, set it to false.

pub fn with_is_current(self, is_current: Option<bool>) -> Self

Set the is_current status of this entry.

By default, this value will be None. Please avoid using this API if it’s unclear whether the entry is current. Set it to true if it is known to be the latest; otherwise, set it to false.

pub fn is_deleted(&self) -> bool

Checks if the file (or version) associated with this metadata has been deleted.

This function returns true if the file represented by this metadata has been marked for deletion or has been permanently deleted. It returns false otherwise, indicating that the file (or version) is still present and accessible.

Refer to docs in Metadata for more information about file versions.

Returns

bool: true if the object is considered deleted, false otherwise.

pub fn set_is_deleted(&mut self, v: bool) -> &mut Self

Set the deleted status of this entry.

pub fn with_is_deleted(self, v: bool) -> Self

Set the deleted status of this entry.

pub fn cache_control(&self) -> Option<&str>

Cache control of this entry.

Cache-Control is defined by RFC 7234 Refer to MDN Cache-Control for more information.

pub fn set_cache_control(&mut self, v: &str) -> &mut Self

Set cache control of this entry.

Cache-Control is defined by RFC 7234 Refer to MDN Cache-Control for more information.

pub fn with_cache_control(self, v: String) -> Self

Set cache control of this entry.

Cache-Control is defined by RFC 7234 Refer to MDN Cache-Control for more information.

pub fn content_length(&self) -> u64

Content length of this entry.

Content-Length is defined by RFC 7230

Refer to MDN Content-Length for more information.

Returns

Content length of this entry. It will be 0 if the content length is not set by the storage services.

pub fn set_content_length(&mut self, v: u64) -> &mut Self

Set content length of this entry.

pub fn with_content_length(self, v: u64) -> Self

Set content length of this entry.

pub fn content_md5(&self) -> Option<&str>

Content MD5 of this entry.

Content MD5 is defined by RFC 2616. And removed by RFC 7231.

OpenDAL will try its best to set this value, but not guarantee this value is the md5 of content.

pub fn set_content_md5(&mut self, v: &str) -> &mut Self

Set content MD5 of this entry.

pub fn with_content_md5(self, v: String) -> Self

Set content MD5 of this entry.

pub fn content_type(&self) -> Option<&str>

Content Type of this entry.

Content Type is defined by RFC 9110.

Refer to MDN Content-Type for more information.

pub fn set_content_type(&mut self, v: &str) -> &mut Self

Set Content Type of this entry.

pub fn with_content_type(self, v: String) -> Self

Set Content Type of this entry.

pub fn content_encoding(&self) -> Option<&str>

Content Encoding of this entry.

Content Encoding is defined by RFC 7231

Refer to MDN Content-Encoding for more information.

pub fn set_content_encoding(&mut self, v: &str) -> &mut Self

Set Content Encoding of this entry.

pub fn content_range(&self) -> Option<BytesContentRange>

Content Range of this entry.

Content Range is defined by RFC 9110.

Refer to MDN Content-Range for more information.

pub fn set_content_range(&mut self, v: BytesContentRange) -> &mut Self

Set Content Range of this entry.

pub fn with_content_range(self, v: BytesContentRange) -> Self

Set Content Range of this entry.

pub fn last_modified(&self) -> Option<DateTime<Utc>>

Last modified of this entry.

Last-Modified is defined by RFC 7232

Refer to MDN Last-Modified for more information.

pub fn set_last_modified(&mut self, v: DateTime<Utc>) -> &mut Self

Set Last modified of this entry.

pub fn with_last_modified(self, v: DateTime<Utc>) -> Self

Set Last modified of this entry.

pub fn etag(&self) -> Option<&str>

ETag of this entry.

ETag is defined by RFC 7232

Refer to MDN ETag for more information.

OpenDAL will return this value AS-IS like the following:

• "33a64df551425fcc55e4d42a148795d9f25f89d4"
• W/"0815"

" is part of etag.

pub fn set_etag(&mut self, v: &str) -> &mut Self

Set ETag of this entry.

pub fn with_etag(self, v: String) -> Self

Set ETag of this entry.

pub fn content_disposition(&self) -> Option<&str>

Content-Disposition of this entry

Content-Disposition is defined by RFC 2616 and clarified usage in RFC 6266.

Refer to MDN Content-Disposition for more information.

OpenDAL will return this value AS-IS like the following:

• “inline”
• “attachment”
• “attachment; filename="filename.jpg"”

pub fn set_content_disposition(&mut self, v: &str) -> &mut Self

Set Content-Disposition of this entry

pub fn with_content_disposition(self, v: String) -> Self

Set Content-Disposition of this entry

pub fn version(&self) -> Option<&str>

Retrieves the version of the file, if available.

The version is typically used in systems that support object versioning, such as AWS S3.

Returns

• Some(&str): If the file has a version associated with it, this function returns Some containing a reference to the version ID string.
• None: If the file does not have a version, or if versioning is not supported or enabled for the underlying storage system, this function returns None.

pub fn set_version(&mut self, v: &str) -> &mut Self

Set the version of the file

pub fn with_version(self, v: String) -> Self

With the version of the file.

pub fn user_metadata(&self) -> Option<&HashMap<String, String>>

User defined metadata of this entry

The prefix of the user defined metadata key(for example: in oss, it’s x-oss-meta-) is remove from the key

pub fn with_user_metadata(self, data: HashMap<String, String>) -> Self

With user defined metadata of this entry

Trait Implementations

impl Clone for Metadata

fn clone(&self) -> Metadata

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Metadata

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Metadata

fn default() -> Metadata

Returns the “default value” for a type.

impl PartialEq for Metadata

fn eq(&self, other: &Metadata) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for Metadata

impl StructuralPartialEq for Metadata