### 0.9.0 / 2019-08-05

* Restore compatibility with Ruby 2.0. This is the last release that will work on end-of-lifed versions of Ruby. The 0.10 release will require Ruby 2.4 or later.
* Update Credentials to use methods for values that are intended to be changed by users, replacing constants.
* Add retry on error for fetch_access_token
* Allow specifying custom state key-values
* Add verbosity none to gcloud command
* Make arity of WebUserAuthorizer#get_credentials compatible with the base class

### 0.8.1 / 2019-03-27

* Silence unnecessary gcloud warning
* Treat empty credentials environment variables as unset

### 0.8.0 / 2019-01-02

* Support connection options :default_connection and :connection_builder when creating credentials that need to refresh OAuth tokens. This lets clients provide connection objects with custom settings, such as proxies, needed for the client environment.
* Removed an unnecessary warning about project IDs.

### 0.7.1 / 2018-10-25

* Make load_gcloud_project_id module function.

### 0.7.0 / 2018-10-24

* Add project_id instance variable to UserRefreshCredentials, ServiceAccountCredentials, and Credentials.

### 0.6.7 / 2018-10-16

* Update memoist dependency to ~> 0.16.

### 0.6.6 / 2018-08-22

* Remove ruby version warnings.

### 0.6.5 / 2018-08-16

* Fix incorrect http verb when revoking credentials.
* Warn on EOL ruby versions.

### 0.6.4 / 2018-08-03

* Resolve issue where DefaultCredentials constant was undefined.

### 0.6.3 / 2018-08-02

* Resolve issue where token_store was being written to twice

### 0.6.2 / 2018-08-01

* Add warning when using cloud sdk credentials

### 0.6.1 / 2017-10-18

* Fix file permissions

### 0.6.0 / 2017-10-17

* Support ruby-jwt 2.0
* Add simple credentials class

### 0.5.3 / 2017-07-21

* Fix file permissions on the gem's `.rb` files.

### 0.5.2 / 2017-07-19

* Add retry mechanism when fetching access tokens in `GCECredentials` and `UserRefreshCredentials` classes.
* Update Google API OAuth2 token credential URI to v4.

### 0.5.1 / 2016-01-06

* Change header name emitted by `Client#apply` from "Authorization" to "authorization" ([@murgatroid99][])
* Fix ADC not working on some windows machines ([@vsubramani][])
[#55](https://github.com/google/google-auth-library-ruby/issues/55)

### 0.5.0 / 2015-10-12

* Initial support for user credentials ([@sqrrrl][])
* Update Signet to 0.7

### 0.4.2 / 2015-08-05

* Updated UserRefreshCredentials hash to use string keys ([@haabaato][])
[#36](https://github.com/google/google-auth-library-ruby/issues/36)

* Add support for a system default credentials file. ([@mr-salty][])
[#33](https://github.com/google/google-auth-library-ruby/issues/33)

* Fix bug when loading credentials from ENV ([@dwilkie][])
[#31](https://github.com/google/google-auth-library-ruby/issues/31)

* Relax the constraint of dependent version of multi_json ([@igrep][])
[#30](https://github.com/google/google-auth-library-ruby/issues/30)

* Enables passing credentials via environment variables. ([@haabaato][])
[#27](https://github.com/google/google-auth-library-ruby/issues/27)

### 0.4.1 / 2015-04-25

* Improves handling of --no-scopes GCE authorization ([@tbetbetbe][])
* Refactoring and cleanup ([@joneslee85][])

### 0.4.0 / 2015-03-25

* Adds an implementation of JWT header auth ([@tbetbetbe][])

### 0.3.0 / 2015-03-23

* makes the scope parameter's optional in all APIs. ([@tbetbetbe][])
* changes the scope parameter's position in various constructors. ([@tbetbetbe][])

[@dwilkie]: https://github.com/dwilkie
[@haabaato]: https://github.com/haabaato
[@igrep]: https://github.com/igrep
[@joneslee85]: https://github.com/joneslee85
[@mr-salty]: https://github.com/mr-salty
[@tbetbetbe]: https://github.com/tbetbetbe
[@murgatroid99]: https://github.com/murgatroid99
[@vsubramani]: https://github.com/vsubramani