add doc

README.md

@@ -71,6 +71,7 @@ can be augmented at runtime by implementing the `Getter` interface.
   * Mercurial
   * HTTP
   * Amazon S3
+  * Google GCP
 
 In addition to the above protocols, go-getter has what are called "detectors."
 These take a URL and attempt to automatically choose the best protocol for
@@ -334,3 +335,14 @@ Some examples for these addressing schemes:
 - bucket.s3-eu-west-1.amazonaws.com/foo/bar
 - "s3::http://127.0.0.1:9000/test-bucket/hello.txt?aws_access_key_id=KEYID&aws_access_key_secret=SECRETKEY&region=us-east-2"
 
+### GCS (`gcs`)
+
+#### GCS Authentication
+
+In order to access to GCS, authentication credentials should be provided. More information can be found [here](https://cloud.google.com/docs/authentication/getting-started)
+
+#### GCS Bucket Examples
+
+- gcs::https://www.googleapis.com/storage/v1/bucket
+- gcs::https://www.googleapis.com/storage/v1/bucket/foo.zip
+- www.googleapis.com/storage/v1/bucket/foo

go.sum

@@ -54,6 +54,7 @@ github.com/hashicorp/go-cleanhttp v0.5.0 h1:wvCrVc9TjDls6+YGAF2hAifE1E5U1+b4tH6K
 github.com/hashicorp/go-cleanhttp v0.5.0/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80=
 github.com/hashicorp/go-safetemp v1.0.0 h1:2HR189eFNrjHQyENnQMMpCiBAsRxzbTMIgBhEyExpmo=
 github.com/hashicorp/go-safetemp v1.0.0/go.mod h1:oaerMy3BhqiTbVye6QuFhFtIceqFoDHxNAB65b+Rj1I=
+github.com/hashicorp/go-version v1.1.0 h1:bPIoEKD27tNdebFGGxxYwcL4nepeY4j1QP23PFRGzg0=
 github.com/hashicorp/go-version v1.1.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
 github.com/jellevandenhooff/dkim v0.0.0-20150330215556-f50fe3d243e1/go.mod h1:E0B/fFc00Y+Rasa88328GlI/XbtyysCtTHZS8h7IrBU=
 github.com/jmespath/go-jmespath v0.0.0-20160202185014-0b12d6b521d8 h1:12VvqtR6Aowv3l/EQUlocDHW2Cp4G9WJVH7uyH8QFJE=