Documentation
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Index ¶
Constants ¶
const ( // RepoFormatVersion is stamped into every repository this build creates. // // It tracks MaxSupportedRepoFormat deliberately. The version is not only a // claim about the bytes currently present — it is the signal that tells // other machines sharing this repository to upgrade. A heterogeneous fleet // is the dangerous state, so a repository touched by a build that can seal // says so, and older builds are told to catch up rather than left writing // alongside it. RepoFormatVersion = 2 // MaxSupportedRepoFormat is the highest version this build can read. A // repository above it is refused rather than misread. // // 2 covers a sealed pack index and a sharded one. Builds before that read // the sealed catalog as unparseable and, without the fixes released in // v1.15.0, as empty — which is how a prune deletes a live repository. They // would also read the pre-shard monolithic catalog as complete when it is // merely stale, which is the same failure by a different route. // // Both changes ship in the same release, so one version covers them. MaxSupportedRepoFormat = 2 // FramedCompressionFormat is the lowest recorded format at which the // compression layer may write framed objects (see pkg/store/compressed.go). // // It gates writes rather than reads: a framed object is always readable, // but a build predating the frame reads one as opaque bytes and returns // them, which is a misread rather than a clean refusal. The version gate // cannot prevent that on its own, because the stamp is applied after a // mutation completes — so a repository still recording format 1 would // otherwise be handed framed objects that an older build sails straight // into. Framing only once the repository already records this version // closes that window without stamping repositories speculatively. FramedCompressionFormat = 2 )
RepoConfig is the repository marker written by "init". It is stored as plaintext at key "config" so it can be read without the encryption key. Key: config Repository format versioning. See docs/compatibility.md for the contract these constants enforce.
RepoFormatVersion is stamped into every repository this build creates. MaxSupportedRepoFormat is the highest version this build can read; a repository above it is refused rather than misread.
Raise both together when a change makes a repository unreadable by earlier builds. Do not raise them for a change earlier builds can still read: a needless bump locks users out of their own data for no benefit.
Variables ¶
This section is empty.
Functions ¶
func ComputeHash ¶
ComputeHash computes the SHA-256 hash of the given data and returns it as a hex string.
func ComputeJSONHash ¶
ComputeJSONHash computes the SHA-256 hash of the JSON representation of the object. This uses encoding/json which sorts map keys, providing a canonical form for basic structs.
Types ¶
type Content ¶
type Content struct {
Type ObjectType `json:"type"` // "content"
Size int64 `json:"size"`
Chunks []string `json:"chunks,omitempty"` // List of "chunk/<sha256>"
DataInlineB64 []byte `json:"data_inline_b64,omitempty"` // For small files
}
Content represents a file's content as a list of chunks Object key: content/<sha256>
type FileMeta ¶
type FileMeta struct {
Version int `json:"version"`
FileID string `json:"fileId"` // Google Drive file ID (HAMT key)
Name string `json:"name"`
Type FileType `json:"type"` // "file" or "folder"
Parents []string `json:"parents"` // List of "filemeta/<sha256>" refs (NOT raw IDs)
Paths []string `json:"paths,omitempty"`
ContentHash string `json:"content_hash"` // SHA256 of the file content
ContentRef string `json:"content_ref,omitempty"` // HMAC(dedupKey, ContentHash) for secure backend lookup
Size int64 `json:"size"`
Mtime int64 `json:"mtime"` // Unix timestamp
Owner string `json:"owner"`
Extra map[string]interface{} `json:"extra,omitempty"`
Mode uint32 `json:"mode,omitempty"` // POSIX permission bits (st_mode & 0xFFF)
Uid uint32 `json:"uid,omitempty"` // POSIX user ID
Gid uint32 `json:"gid,omitempty"` // POSIX group ID
Btime int64 `json:"btime,omitempty"` // birth/creation time, Unix seconds; 0 = not available
Flags uint32 `json:"flags,omitempty"` // per-file flags (chflags / FS_IOC_GETFLAGS)
Xattrs map[string][]byte `json:"xattrs,omitempty"` // extended attributes: name → raw bytes
}
FileMeta represents immutable file metadata Object key: filemeta/<sha256>
type FileType ¶
type FileType string
FileType defines the generic type of the file (e.g. generic file, folder, symlink)
type HAMTNode ¶
type HAMTNode struct {
Type ObjectType `json:"type"` // "internal" or "leaf"
Bitmap uint32 `json:"bitmap,omitempty"`
Children []string `json:"children,omitempty"` // ["node/<sha256>", ...]
Entries []LeafEntry `json:"entries,omitempty"`
}
HAMTNode represents a node in the Merkle-HAMT Object key: node/<sha256>
type Index ¶
type Index struct {
LatestSnapshot string `json:"latest_snapshot"` // "snapshot/<sha256>"
Seq int `json:"seq"`
}
Index represents a pointer to the latest snapshot Key: index/latest
type LeafEntry ¶
type LeafEntry struct {
Key string `json:"key"` // caller's entry key (the source file ID)
PathKey string `json:"path_key,omitempty"` // routing key; falls back to SHA256(Key) if empty
Value string `json:"filemeta"` // "filemeta/<sha256>"
}
LeafEntry represents an entry in a Leaf node. The HAMT treats Value as opaque; the backup engine stores filemeta refs in it, which is why the wire tag is "filemeta".
type ObjectType ¶
type ObjectType string
ObjectType defines the type of the object in the system
const ( ObjectTypeContent ObjectType = "content" ObjectTypeInternal ObjectType = "internal" ObjectTypeLeaf ObjectType = "leaf" )
type RepoConfig ¶
type Snapshot ¶
type Snapshot struct {
Version int `json:"version"`
Created string `json:"created"` // ISO8601
Root string `json:"root"` // "node/<sha256>"
Seq int `json:"seq"`
Source *SourceInfo `json:"source,omitempty"`
Meta map[string]string `json:"meta,omitempty"`
Tags []string `json:"tags,omitempty"`
ChangeToken string `json:"change_token,omitempty"`
ExcludeHash string `json:"exclude_hash,omitempty"`
}
Snapshot represents a backup checkpoint Object key: snapshot/<sha256>
type SnapshotSummary ¶
type SnapshotSummary struct {
Ref string `json:"ref"` // "snapshot/<hash>"
Seq int `json:"seq"`
Created string `json:"created"` // ISO8601
Root string `json:"root"` // "node/<hash>"
Source *SourceInfo `json:"source,omitempty"`
Tags []string `json:"tags,omitempty"`
ChangeToken string `json:"change_token,omitempty"`
ExcludeHash string `json:"exclude_hash,omitempty"`
}
SnapshotSummary is a lightweight representation of a snapshot stored in the snapshot catalog index. It contains enough metadata for listing, filtering, and finding the previous snapshot without having to fetch the full object.
type SourceInfo ¶
type SourceInfo struct {
Type string `json:"type"` // e.g. "gdrive", "local"
Account string `json:"account,omitempty"` // friendly account/host label for display
Path string `json:"path,omitempty"` // display path within the source container
Identity string `json:"identity,omitempty"` // stable container identity for lineage matching
PathID string `json:"path_id,omitempty"` // stable selected-root identity within container
DriveName string `json:"drive_name,omitempty"` // human-readable container label (e.g. "My Drive")
FsType string `json:"fs_type,omitempty"` // source filesystem type (e.g. "apfs", "ext4", "sftp")
}
SourceInfo describes the origin of a backup snapshot. It is stored as a first-class field on the snapshot so that forget policies can group by source identity (Type + Account + Path).
Source Files