gophire

README

GoPhire

Google-Cloud or Fire-Base storage api wrapper.

Simplified methods to help when working with Google Storage Buckets.

Currently, only Storage works. Additional modules will be added in the future and are a work in progress

Wtih this library you can

• DownloadFile()
• UploadFile()
• GetFileAttributes()
• Init() Initialize
• SayHi()

How To Use

• go get cloud.google.com/go/storage
• go get google.golang.org/api/option
• go get github.com/JaviAir/GoPhire

• Create a Firebase or Google Cloud project.
• Create a Service Account Key for that project.

• Open a Go project file.

Ex. main.go

• import the GoPhire/Storage module

Ex. import ( "github.com/JaviAir/GoPhire/Storage" )

• Initialize a variable with your Service Account Key json data pasted as a string.

Ex. serviceKey := {ServiceAccountKey Json Data pasted from ServiceAccountKey.json}

• Initialize the Storage module by calling the Init() method.

• Pass in the serviceKey variable, and your default storage bucket name as a string WITHOUT the gs:// prefix.
• Ex. Storage.Init(serviceKey, "bucketname")

Initialize Storage

• This library will not work without running the Init() method first. The Init() method takes in 2 string args.
• arg1: the service key json data
• arg2: the bucket name without the "gs://" prefix

These are used to initialize default values required by all the other methods in the storage library.

• You can change the bucket name later after you have chosen the default bucket.
• Note: all buckets must be accessible under the same service key.
• • If trying to access a file from a bucket that needs another service key.
• • You will have to re-initialize the library.
• • Meaning get the new service key data and run the Storage.Init() method again with the new data.

• Once the Storage module has been initialized you can use the other methods.

Download File

• Ex. Storage.DownloadFile("../mypenguins.jpg", "myStorageDir/Penguins.jpg")
• or
• Ex. opt := Storage.OptionalParameters{ShowStatusPercentage: true}
• Storage.DownloadFile("../mypenguins.jpg", "myStorageDir/Penguins.jpg", opt)

• Arg1: string of destination path/name to save file as.
• Arg2: string of path to source file on the storage bucket.
• arg3: Optional parameters. (Optional, can be excluded completely.)
• When referencing a storage path there must be no leading forward slash. So the root path would be "".

Upload File

• Ex. Storage.UploadFile("myStorageDir/", "./mypenguins.jpg")
• or
• Ex. opt := Storage.OptionalParameters{ShowStatusPercentage: true}
• Storage.UploadFile("", "./mypenguins.jpg", opt)

• Arg1: string of destination path on the bucket to save file as.
• Arg2: string of path to local source file.
• arg3: Optional parameters. (Optional, can be excluded completely.)
• When referencing a storage path there must be no leading forward slash. So the root path would be "".

Optional Parameters

Methods DownloadFile(), UploadFile(), and GetFileAttributes() can take in optional paramters. These optional parameters can be:

• CustomBucket string // default is bucket passed from Init() method
• ConnTimeout int // default is 50 seconds
• Permission fs.FileMode // default is 0644 or 0777, depending on next param
• ShowStatusPercentage bool // default is false

• ShowStatusPercentage
• if true this prints, (fmt), the progress of the download or upload. In ONE line. (Multiple shown for example purposes.)

• Ex. Downloading... 2 % complete. (777835 bytes)
• Ex. Downloading... 69 % complete. (777835 bytes)
• Ex. Downloading... 100 % complete. (777835 bytes)

Get File Attributes

• returns // File name is: LatestStorageDir/Penguins.jpg , File Size is 777835

attrs, err := Storage.GetFileAttributes("LatestStorageDir/Penguins.jpg")
if err != nil {
	fmt.Println(err)
}
fmt.Printf("File name is: %s , File Size is %d \n", attrs.Name, attrs.Size)

• This method returns an attributes object that contains all the values a storage bucket creates when it recieves the file.

// ObjectAttrs represents the metadata for a Google Cloud Storage (GCS) object.

// Bucket is the name of the bucket containing this GCS object.
// This field is read-only.
Bucket string

// Name is the name of the object within the bucket.
// This field is read-only.
Name string

// ContentType is the MIME type of the object's content.
ContentType string

// ContentLanguage is the content language of the object's content.
ContentLanguage string

// CacheControl is the Cache-Control header to be sent in the response
// headers when serving the object data.
CacheControl string

// EventBasedHold specifies whether an object is under event-based hold. New
// objects created in a bucket whose DefaultEventBasedHold is set will
// default to that value.
EventBasedHold bool

// TemporaryHold specifies whether an object is under temporary hold. While
// this flag is set to true, the object is protected against deletion and
// overwrites.
TemporaryHold bool

// RetentionExpirationTime is a server-determined value that specifies the
// earliest time that the object's retention period expires.
// This is a read-only field.
RetentionExpirationTime time.Time

// ACL is the list of access control rules for the object.
ACL []ACLRule

// If not empty, applies a predefined set of access controls. It should be set
// only when writing, copying or composing an object. When copying or composing,
// it acts as the destinationPredefinedAcl parameter.
// PredefinedACL is always empty for ObjectAttrs returned from the service.
// See https://cloud.google.com/storage/docs/json_api/v1/objects/insert
// for valid values.
PredefinedACL string

// Owner is the owner of the object. This field is read-only.
//
// If non-zero, it is in the form of "user-<userId>".
Owner string

// Size is the length of the object's content. This field is read-only.
Size int64

// ContentEncoding is the encoding of the object's content.
ContentEncoding string

// ContentDisposition is the optional Content-Disposition header of the object
// sent in the response headers.
ContentDisposition string

// MD5 is the MD5 hash of the object's content. This field is read-only,
// except when used from a Writer. If set on a Writer, the uploaded
// data is rejected if its MD5 hash does not match this field.
MD5 []byte

// CRC32C is the CRC32 checksum of the object's content using the Castagnoli93
// polynomial. This field is read-only, except when used from a Writer or
// Composer. In those cases, if the SendCRC32C field in the Writer or Composer
// is set to is true, the uploaded data is rejected if its CRC32C hash does
// not match this field.
CRC32C uint32

// MediaLink is an URL to the object's content. This field is read-only.
MediaLink string

// Metadata represents user-provided metadata, in key/value pairs.
// It can be nil if no metadata is provided.
Metadata map[string]string

// Generation is the generation number of the object's content.
// This field is read-only.
Generation int64

// Metageneration is the version of the metadata for this
// object at this generation. This field is used for preconditions
// and for detecting changes in metadata. A metageneration number
// is only meaningful in the context of a particular generation
// of a particular object. This field is read-only.
Metageneration int64

// StorageClass is the storage class of the object. This defines
// how objects are stored and determines the SLA and the cost of storage.
// Typical values are "STANDARD", "NEARLINE", "COLDLINE" and "ARCHIVE".
// Defaults to "STANDARD".
// See https://cloud.google.com/storage/docs/storage-classes for all
// valid values.
StorageClass string

// Created is the time the object was created. This field is read-only.
Created time.Time

// Deleted is the time the object was deleted.
// If not deleted, it is the zero value. This field is read-only.
Deleted time.Time

// Updated is the creation or modification time of the object.
// For buckets with versioning enabled, changing an object's
// metadata does not change this property. This field is read-only.
Updated time.Time

// CustomerKeySHA256 is the base64-encoded SHA-256 hash of the
// customer-supplied encryption key for the object. It is empty if there is
// no customer-supplied encryption key.
// See // https://cloud.google.com/storage/docs/encryption for more about
// encryption in Google Cloud Storage.
CustomerKeySHA256 string

// Cloud KMS key name, in the form
// projects/P/locations/L/keyRings/R/cryptoKeys/K, used to encrypt this object,
// if the object is encrypted by such a key.
//
// Providing both a KMSKeyName and a customer-supplied encryption key (via
// ObjectHandle.Key) will result in an error when writing an object.
KMSKeyName string

// Prefix is set only for ObjectAttrs which represent synthetic "directory
// entries" when iterating over buckets using Query.Delimiter. See
// ObjectIterator.Next. When set, no other fields in ObjectAttrs will be
// populated.
Prefix string

// Etag is the HTTP/1.1 Entity tag for the object.
// This field is read-only.
Etag string

// A user-specified timestamp which can be applied to an object. This is
// typically set in order to use the CustomTimeBefore and DaysSinceCustomTime
// LifecycleConditions to manage object lifecycles.
//
// CustomTime cannot be removed once set on an object. It can be updated to a
// later value but not to an earlier one. For more information see
// https://cloud.google.com/storage/docs/metadata#custom-time .
CustomTime time.Time