Documentation ¶
Overview ¶
Package schema manipulates Camlistore schema blobs.
A schema blob is a JSON-encoded blob that describes other blobs. See documentation in Perkeep's doc/schema/ directory.
Index ¶
- Constants
- Variables
- func FileTime(f io.ReaderAt) (time.Time, error)
- func IsInterestingTitle(title string) bool
- func IsMissingField(err error) bool
- func IsZoneKnown(t time.Time) bool
- func LikelySchemaBlob(buf []byte) bool
- func RFC3339FromTime(t time.Time) string
- func WriteFileChunks(ctx context.Context, bs blobserver.StatReceiver, file *Builder, r io.Reader) error
- func WriteFileFromReader(ctx context.Context, bs blobserver.StatReceiver, filename string, r io.Reader) (blob.Ref, error)
- func WriteFileFromReaderWithModTime(ctx context.Context, bs blobserver.StatReceiver, filename string, ...) (blob.Ref, error)
- func WriteFileMap(ctx context.Context, bs blobserver.StatReceiver, file *Builder, r io.Reader) (blob.Ref, error)
- type AnyBlob
- type Blob
- func (b *Blob) AsClaim() (c Claim, ok bool)
- func (b *Blob) AsShare() (s Share, ok bool)
- func (b *Blob) AsStaticFile() (sf StaticFile, ok bool)
- func (b *Blob) Blob() *Blob
- func (b *Blob) BlobRef() blob.Ref
- func (b *Blob) Builder() *Builder
- func (b *Blob) ByteParts() []BytesPart
- func (b *Blob) ClaimDate() (time.Time, error)
- func (b *Blob) DirectoryEntries() (br blob.Ref, ok bool)
- func (b *Blob) FileMode() os.FileMode
- func (b *Blob) FileName() string
- func (b *Blob) JSON() string
- func (b *Blob) MapGid() int
- func (b *Blob) MapUid() int
- func (b *Blob) ModTime() time.Time
- func (b *Blob) NewDirReader(ctx context.Context, fetcher blob.Fetcher) (*DirReader, error)
- func (b *Blob) NewFileReader(fetcher blob.Fetcher) (*FileReader, error)
- func (b *Blob) PartsSize() int64
- func (b *Blob) ShareAuthType() string
- func (b *Blob) ShareTarget() blob.Ref
- func (b *Blob) StaticSetMembers() []blob.Ref
- func (b *Blob) StaticSetMergeSets() []blob.Ref
- func (b *Blob) Type() string
- type Buildable
- type Builder
- func NewAddAttributeClaim(permaNode blob.Ref, attr, value string) *Builder
- func NewBuilder() *Builder
- func NewCommonFileMap(fileName string, fi os.FileInfo) *Builder
- func NewDelAttributeClaim(permaNode blob.Ref, attr, value string) *Builder
- func NewDeleteClaim(target blob.Ref) *Builder
- func NewDirMap(fileName string) *Builder
- func NewFileMap(fileName string) *Builder
- func NewHashPlannedPermanode(h hash.Hash) *Builder
- func NewPlannedPermanode(key string) *Builder
- func NewSetAttributeClaim(permaNode blob.Ref, attr, value string) *Builder
- func NewShareRef(authType string, transitive bool) *Builder
- func NewStaticSet() *Builder
- func NewUnsignedPermanode() *Builder
- func (bb *Builder) Blob() *Blob
- func (bb *Builder) Builder() *Builder
- func (bb *Builder) CapCreationTime() *Builder
- func (bb *Builder) ClaimType() ClaimType
- func (bb *Builder) IsClaimType() bool
- func (bb *Builder) JSON() (string, error)
- func (bb *Builder) ModTime() (t time.Time, ok bool)
- func (bb *Builder) PartsSize() int64
- func (bb *Builder) PopulateDirectoryMap(staticSetRef blob.Ref) *Builder
- func (bb *Builder) PopulateParts(size int64, parts []BytesPart) error
- func (bb *Builder) SetClaimDate(t time.Time) *Builder
- func (bb *Builder) SetFileName(name string) *Builder
- func (bb *Builder) SetModTime(t time.Time) *Builder
- func (bb *Builder) SetRawStringField(key, value string) *Builder
- func (bb *Builder) SetShareExpiration(t time.Time) *Builder
- func (bb *Builder) SetShareIsTransitive(b bool) *Builder
- func (bb *Builder) SetShareSearch(q SearchQuery) *Builder
- func (bb *Builder) SetShareTarget(t blob.Ref) *Builder
- func (bb *Builder) SetSigner(signer blob.Ref) *Builder
- func (bb *Builder) SetStaticSetMembers(members []blob.Ref) []*Blob
- func (bb *Builder) SetSymlinkTarget(target string) *Builder
- func (bb *Builder) SetType(t string) *Builder
- func (bb *Builder) Sign(ctx context.Context, signer *Signer) (string, error)
- func (bb *Builder) SignAt(ctx context.Context, signer *Signer, sigTime time.Time) (string, error)
- func (bb *Builder) Type() string
- type BytesPart
- type Claim
- type ClaimType
- type DirReader
- type Directory
- type DirectoryEntry
- type FIFO
- type File
- type FileReader
- func (fr *FileReader) Close() error
- func (fr *FileReader) FileMode() os.FileMode
- func (fr *FileReader) FileName() string
- func (fr *FileReader) ForeachChunk(ctx context.Context, fn func(schemaPath []blob.Ref, p BytesPart) error) error
- func (fr *FileReader) LoadAllChunks()
- func (fr *FileReader) ModTime() time.Time
- func (fr *FileReader) ReadAt(p []byte, offset int64) (n int, err error)
- func (fr *FileReader) SchemaBlobRef() blob.Ref
- func (fr *FileReader) UnixMtime() time.Time
- type MissingFieldError
- type SearchQuery
- type Share
- type Signer
- type Socket
- type StatHasher
- type StaticFIFO
- type StaticFile
- type StaticSocket
- type StaticSymlink
- type Symlink
Constants ¶
const MaxSchemaBlobSize = 1 << 20
MaxSchemaBlobSize represents the upper bound for how large a schema blob may be.
ShareHaveRef is the auth type specifying that if you "have the reference" (know the blobref to the haveref share blob), then you have access to the referenced object from that share blob. This is the "send a link to a friend" access model.
Variables ¶
var DefaultStatHasher = &defaultStatHasher{}
var (
ErrNoCamliVersion = errors.New("schema: no camliVersion key in map")
)
var UnknownLocation = time.FixedZone("Unknown", -60) // 1 minute west
UnknownLocation is a magic timezone value used when the actual location of a time is unknown. For instance, EXIF files commonly have a time without a corresponding location or timezone offset.
Functions ¶
func FileTime ¶
FileTime returns the best guess of the file's creation time (or modtime). If the file doesn't have its own metadata indication the creation time (such as in EXIF), FileTime uses the modification time from the file system. It there was a valid EXIF but an error while trying to get a date from it, it logs the error and tries the other methods.
func IsInterestingTitle ¶
IsInterestingTitle returns whether title would be interesting information as a title for a permanode. For example, filenames automatically created by cameras, such as IMG_XXXX.JPG, do not add any interesting value.
func IsMissingField ¶
IsMissingField returns whether error is of type MissingFieldError.
func IsZoneKnown ¶
IsZoneKnown reports whether t is in a known timezone. Perkeep uses the magic timezone offset of 1 minute west of UTC to mean that the timezone wasn't known.
func LikelySchemaBlob ¶
LikelySchemaBlob returns quickly whether buf likely contains (or is the prefix of) a schema blob.
func RFC3339FromTime ¶
RFC3339FromTime returns an RFC3339-formatted time.
If the timezone is known, the time will be converted to UTC and returned with a "Z" suffix. For unknown zones, the timezone will be "-00:01" (1 minute west of UTC).
Fractional seconds are only included if the time has fractional seconds.
func WriteFileChunks ¶
func WriteFileChunks(ctx context.Context, bs blobserver.StatReceiver, file *Builder, r io.Reader) error
WriteFileChunks uploads chunks of r to bs while populating file. It does not upload file.
func WriteFileFromReader ¶
func WriteFileFromReader(ctx context.Context, bs blobserver.StatReceiver, filename string, r io.Reader) (blob.Ref, error)
WriteFileFromReader creates and uploads a "file" JSON schema composed of chunks of r, also uploading the chunks. The returned BlobRef is of the JSON file schema blob. The filename is optional.
func WriteFileFromReaderWithModTime ¶
func WriteFileFromReaderWithModTime(ctx context.Context, bs blobserver.StatReceiver, filename string, modTime time.Time, r io.Reader) (blob.Ref, error)
WriteFileFromReaderWithModTime creates and uploads a "file" JSON schema composed of chunks of r, also uploading the chunks. The returned BlobRef is of the JSON file schema blob. Both filename and modTime are optional.
func WriteFileMap ¶
func WriteFileMap(ctx context.Context, bs blobserver.StatReceiver, file *Builder, r io.Reader) (blob.Ref, error)
WriteFileMap uploads chunks of r to bs while populating file and finally uploading file's Blob. The returned blobref is of file's JSON blob.
Types ¶
type Blob ¶
type Blob struct {
// contains filtered or unexported fields
}
A Blob represents a Perkeep schema blob. It is immutable.
func BlobFromReader ¶
BlobFromReader returns a new Blob from the provided Reader r, which should be the body of the provided blobref. Note: the hash checksum is not verified.
func (*Blob) AsStaticFile ¶
func (b *Blob) AsStaticFile() (sf StaticFile, ok bool)
AsStaticFile returns the Blob as a StaticFile if it represents one. Otherwise, it returns false in the boolean parameter and the zero value of StaticFile.
func (*Blob) ClaimDate ¶
ClaimDate returns the "claimDate" field. If there is no claimDate, the error will be a MissingFieldError.
func (*Blob) DirectoryEntries ¶
DirectoryEntries the "entries" field if valid and b's type is "directory".
func (*Blob) FileName ¶
FileName returns the file, directory, or symlink's filename, or the empty string. TODO: move this off *Blob to a specialized type.
func (*Blob) MapGid ¶
MapGid returns the most appropriate mapping from this file's group to the local machine's group, trying first a match by name, followed by just mapping the number through directly.
func (*Blob) MapUid ¶
MapUid returns the most appropriate mapping from this file's owner to the local machine's owner, trying first a match by name, followed by just mapping the number through directly.
func (*Blob) NewDirReader ¶
func (*Blob) NewFileReader ¶
func (b *Blob) NewFileReader(fetcher blob.Fetcher) (*FileReader, error)
func (*Blob) PartsSize ¶
PartsSize returns the number of bytes represented by the "parts" field. TODO: move this off *Blob to a specialized type.
func (*Blob) ShareAuthType ¶
func (*Blob) ShareTarget ¶
func (*Blob) StaticSetMembers ¶
StaticSetMembers returns the refs in the "members" field if b is a valid "static-set" schema. Note that if it is a large static-set, the members are actually spread as subsets in "mergeSets". See StaticSetMergeSets.
func (*Blob) StaticSetMergeSets ¶
StaticSetMergeSets returns the refs of the static-sets in "mergeSets". These are the subsets of all the static-set members in the case of a large directory.
type Buildable ¶
type Buildable interface {
Builder() *Builder
}
Buildable returns a Builder from a base.
type Builder ¶
type Builder struct {
// contains filtered or unexported fields
}
A Builder builds a JSON blob. After mutating the Builder, call Blob to get the built blob.
func NewAddAttributeClaim ¶
func NewBuilder ¶
func NewBuilder() *Builder
NewBuilder returns a new blob schema builder. The "camliVersion" field is set to "1" by default and the required "camliType" field is NOT set.
func NewDelAttributeClaim ¶
NewDelAttributeClaim creates a new claim to remove value from the values set for the attribute attr of permaNode. If value is empty then all the values for attribute are cleared.
func NewDeleteClaim ¶
NewDeleteClaim creates a new claim to delete a target claim or permanode.
func NewDirMap ¶
NewDirMap returns a new builder of a type "directory" schema for the provided fileName.
func NewFileMap ¶
NewFileMap returns a new builder of a type "file" schema for the provided fileName. The chunk parts of the file are not populated.
func NewHashPlannedPermanode ¶
NewHashPlannedPermanode returns a planned permanode with the sum of the hash, prefixed with "sha1-", as the key.
func NewPlannedPermanode ¶
NewPlannedPermanode returns a permanode with a fixed key. Like NewUnsignedPermanode, this builder is also not yet signed. Callers of NewPlannedPermanode must sign the map with a fixed claimDate and GPG date to create consistent JSON encodings of the Map (its blobref), between runs.
func NewSetAttributeClaim ¶
func NewShareRef ¶
NewShareRef creates a *Builder for a "share" claim.
func NewStaticSet ¶
func NewStaticSet() *Builder
NewStaticSet returns the "static-set" schema for a directory. Its members should be populated with SetStaticSetMembers.
func NewUnsignedPermanode ¶
func NewUnsignedPermanode() *Builder
NewUnsignedPermanode returns a new random permanode, not yet signed.
func (*Builder) Blob ¶
Blob builds the Blob. The builder continues to be usable after a call to Build.
func (*Builder) CapCreationTime ¶
CapCreationTime caps the "unixCtime" field to be less or equal than "unixMtime"
func (*Builder) IsClaimType ¶
IsClaimType returns whether this blob builder is for a type which should be signed. (a "claim" or "permanode")
func (*Builder) PopulateDirectoryMap ¶
PopulateDirectoryMap sets the type of *Builder to "directory" and sets the "entries" field to the provided staticSet blobref.
func (*Builder) PopulateParts ¶
PopulateParts sets the "parts" field of the blob with the provided parts. The sum of the sizes of parts must match the provided size or an error is returned. Also, each BytesPart may only contain either a BytesPart or a BlobRef, but not both.
func (*Builder) SetClaimDate ¶
SetClaimDate sets the "claimDate" on a claim. It is a fatal error to call SetClaimDate if the Map isn't of Type "claim".
func (*Builder) SetFileName ¶
SetFileName sets the fileName or fileNameBytes field. The filename is truncated to just the base.
func (*Builder) SetModTime ¶
SetModTime sets the "unixMtime" field.
func (*Builder) SetRawStringField ¶
SetRawStringField sets a raw string field in the underlying map.
func (*Builder) SetShareExpiration ¶
SetShareExpiration sets the expiration time on share claim. It panics if bb isn't a "share" claim type. If t is zero, the expiration is removed.
func (*Builder) SetShareIsTransitive ¶
func (*Builder) SetShareSearch ¶
func (bb *Builder) SetShareSearch(q SearchQuery) *Builder
SetShareSearch sets the search of share claim. q is assumed to be of type *search.SearchQuery. It panics if bb isn't a "share" claim type.
func (*Builder) SetShareTarget ¶
SetShareTarget sets the target of share claim. It panics if bb isn't a "share" claim type.
func (*Builder) SetSigner ¶
SetSigner sets the camliSigner field. Calling SetSigner is unnecessary if using Sign.
func (*Builder) SetStaticSetMembers ¶
SetStaticSetMembers sets the given members as the static-set members of this builder. If the members are so numerous that they would not fit on a schema blob, they are spread (recursively, if needed) onto sub static-sets. In which case, these subsets are set as "mergeSets" of this builder. All the created subsets are returned, so the caller can upload them along with the top static-set created from this builder. SetStaticSetMembers panics if bb isn't a "static-set" claim type.
func (*Builder) SetSymlinkTarget ¶
SetSymlinkTarget sets bb to be of type "symlink" and sets the symlink's target.
func (*Builder) Sign ¶
Sign sets the blob builder's camliSigner field with SetSigner and returns the signed JSON using the provided signer.
type BytesPart ¶
type BytesPart struct { // Size is the number of bytes that this part contributes to the overall segment. Size uint64 `json:"size"` // At most one of BlobRef or BytesRef must be non-zero // (Valid), but it's illegal for both. // If neither are set, this BytesPart represents Size zero bytes. // BlobRef refers to raw bytes. BytesRef references a "bytes" schema blob. BlobRef blob.Ref `json:"blobRef,omitempty"` BytesRef blob.Ref `json:"bytesRef,omitempty"` // Offset optionally specifies the offset into BlobRef to skip // when reading Size bytes. Offset uint64 `json:"offset,omitempty"` }
BytesPart is the type representing one of the "parts" in a "file" or "bytes" JSON schema.
See doc/schema/bytes.txt and doc/schema/files/file.txt.
type Claim ¶
type Claim struct {
// contains filtered or unexported fields
}
A Claim is a Blob that is signed.
func (Claim) ClaimDateString ¶
ClaimDateString returns the blob's "claimDate" field.
func (Claim) ModifiedPermanode ¶
ModifiedPermanode returns the claim's "permaNode" field, if it's a claim that modifies a permanode. Otherwise a zero blob.Ref is returned.
type ClaimType ¶
type ClaimType string
ClaimType is one of the valid "claimType" fields in a "claim" schema blob. See doc/schema/claims/.
type DirReader ¶
type DirReader struct {
// contains filtered or unexported fields
}
A DirReader reads the entries of a "directory" schema blob's referenced "static-set" blob.
func NewDirReader ¶
func NewDirReader(ctx context.Context, fetcher blob.Fetcher, dirBlobRef blob.Ref) (*DirReader, error)
NewDirReader creates a new directory reader and prepares to fetch the static-set entries
type Directory ¶
type Directory interface { // Readdir reads the contents of the directory associated with dr // and returns an array of up to n DirectoryEntries structures. // Subsequent calls on the same file will yield further // DirectoryEntries. // If n > 0, Readdir returns at most n DirectoryEntry structures. In // this case, if Readdir returns an empty slice, it will return // a non-nil error explaining why. At the end of a directory, // the error is os.EOF. // If n <= 0, Readdir returns all the DirectoryEntries from the // directory in a single slice. In this case, if Readdir succeeds // (reads all the way to the end of the directory), it returns the // slice and a nil os.Error. If it encounters an error before the // end of the directory, Readdir returns the DirectoryEntry read // until that point and a non-nil error. Readdir(ctx context.Context, n int) ([]DirectoryEntry, error) }
Directory is a read-only interface to a "directory" schema blob.
type DirectoryEntry ¶
type DirectoryEntry interface { // CamliType returns the schema blob's "camliType" field. // This may be "file", "directory", "symlink", or other more // obscure types added in the future. CamliType() string FileName() string BlobRef() blob.Ref File(ctx context.Context) (File, error) // if camliType is "file" Directory(ctx context.Context) (Directory, error) // if camliType is "directory" Symlink() (Symlink, error) // if camliType is "symlink" FIFO() (FIFO, error) // if camliType is "fifo" Socket() (Socket, error) // If camliType is "socket" }
DirectoryEntry is a read-only interface to an entry in a (static) directory.
func NewDirectoryEntryFromBlobRef ¶
func NewDirectoryEntryFromBlobRef(ctx context.Context, fetcher blob.Fetcher, blobRef blob.Ref) (DirectoryEntry, error)
NewDirectoryEntryFromBlobRef takes a BlobRef and returns a
DirectoryEntry if the BlobRef contains a type "file", "directory", "symlink", "fifo" or "socket".
TODO: ""char", "block", probably. later.
type FileReader ¶
type FileReader struct { // Immutable stuff: *io.SectionReader // provides Read, Seek, and Size. // contains filtered or unexported fields }
A FileReader reads the bytes of "file" and "bytes" schema blobrefs.
func NewFileReader ¶
func NewFileReader(ctx context.Context, fetcher blob.Fetcher, fileBlobRef blob.Ref) (*FileReader, error)
NewFileReader returns a new FileReader reading the contents of fileBlobRef, fetching blobs from fetcher. The fileBlobRef must be of a "bytes" or "file" schema blob.
The caller should call Close on the FileReader when done reading.
func (*FileReader) FileMode ¶
func (fr *FileReader) FileMode() os.FileMode
func (*FileReader) FileName ¶
func (fr *FileReader) FileName() string
FileName returns the file schema's filename, if any.
func (*FileReader) ForeachChunk ¶
func (fr *FileReader) ForeachChunk(ctx context.Context, fn func(schemaPath []blob.Ref, p BytesPart) error) error
ForeachChunk calls fn for each chunk of fr, in order.
The schemaPath argument will be the path from the "file" or "bytes" schema blob down to possibly other "bytes" schema blobs, the final one of which references the given BytesPart. The BytesPart will be the actual chunk. The fn function will not be called with BytesParts referencing a "BytesRef"; those are followed recursively instead. The fn function must not retain or mutate schemaPath.
If fn returns an error, iteration stops and that error is returned from ForeachChunk. Other errors may be returned from ForeachChunk if schema blob fetches fail.
func (*FileReader) LoadAllChunks ¶
func (fr *FileReader) LoadAllChunks()
LoadAllChunks starts a process of loading all chunks of this file as quickly as possible. The contents are immediately discarded, so it is assumed that the fetcher is a caching fetcher.
func (*FileReader) ModTime ¶
func (fr *FileReader) ModTime() time.Time
func (*FileReader) SchemaBlobRef ¶
func (fr *FileReader) SchemaBlobRef() blob.Ref
func (*FileReader) UnixMtime ¶
func (fr *FileReader) UnixMtime() time.Time
UnixMtime returns the file schema's UnixMtime field, or the zero value.
type MissingFieldError ¶
type MissingFieldError string
A MissingFieldError represents a missing JSON field in a schema blob.
func (MissingFieldError) Error ¶
func (e MissingFieldError) Error() string
type SearchQuery ¶
type SearchQuery interface{}
A SearchQuery must be of type *search.SearchQuery. This type breaks an otherwise-circular dependency.
type Share ¶
type Share struct {
}A Share is a claim for giving access to a user's blob(s). When returned from (*Blob).AsShare, it always represents a valid share with all required fields.
func (Share) IsTransitive ¶
IsTransitive returns whether the Share transitively gives access to everything reachable from the referenced blob.
type Signer ¶
type Signer struct {
// contains filtered or unexported fields
}
A Signer signs the JSON schema blobs that require signing, such as claims and permanodes.
func NewSigner ¶
func NewSigner(pubKeyRef blob.Ref, armoredPubKey io.Reader, privateKeySource interface{}) (*Signer, error)
NewSigner returns an Signer given an armored public key's blobref, its armored content, and its associated private key entity. The privateKeySource must be either an *openpgp.Entity or a string filename to a secret key.
func (*Signer) Entity ¶
Entity returns the signer's entity, which includes its public and private keys.
type Socket ¶
type Socket interface { }
Socket is the read-only interface to a "socket" schema blob.
type StatHasher ¶
type StaticFIFO ¶
type StaticFIFO struct {
StaticFile
}
A StaticFIFO is a StaticFile that is also a fifo.
type StaticFile ¶
type StaticFile struct {
// contains filtered or unexported fields
}
A StaticFile is a Blob representing a file, symlink fifo or socket (or device file, when support for these is added).
func (StaticFile) AsStaticFIFO ¶
func (sf StaticFile) AsStaticFIFO() (fifo StaticFIFO, ok bool)
AsStaticFIFO returns the StatifFile as a StaticFIFO if the StaticFile represents a fifo. Otherwise, it returns the zero value of StaticFIFO and false.
func (StaticFile) AsStaticSocket ¶
func (sf StaticFile) AsStaticSocket() (ss StaticSocket, ok bool)
AsStaticSocket returns the StaticFile as a StaticSocket if the StaticFile represents a socket. Otherwise, it returns the zero value of StaticSocket and false.
func (StaticFile) AsStaticSymlink ¶
func (sf StaticFile) AsStaticSymlink() (s StaticSymlink, ok bool)
AsStaticSymlink returns the StaticFile as a StaticSymlink if the StaticFile represents a symlink. Othwerwise, it returns the zero value of StaticSymlink and false.
func (StaticFile) FileName ¶
func (sf StaticFile) FileName() string
FileName returns the StaticFile's FileName if is not the empty string, otherwise it returns its FileNameBytes concatenated into a string.
type StaticSocket ¶
type StaticSocket struct {
StaticFile
}
A StaticSocket is a StaticFile that is also a socket.
type StaticSymlink ¶
type StaticSymlink struct { // We name it `StaticSymlink' rather than just `Symlink' since // a type called Symlink is already in schema.go. StaticFile }
A StaticSymlink is a StaticFile that is also a symbolic link.
func (StaticSymlink) SymlinkTargetString ¶
func (sl StaticSymlink) SymlinkTargetString() string
SymlinkTargetString returns the field symlinkTarget if is non-empty. Otherwise it returns the contents of symlinkTargetBytes concatenated as a string.