Complete the steps described in the rest of this page to create a simple Go command-line application that makes requests to the Google Calendar API.
Prerequisites
To run this quickstart, you need the following prerequisites:
- Go, latest version recommended.
- Git, latest version recommended.
- A Google Cloud Platform project with the API enabled. To create a project and enable an API, refer to Create a project and enable the API
- Authorization credentials for a desktop application. To learn how to create credentials for a desktop application, refer to Create credentials.
- A Google account with Google Calendar enabled.
Step 1: Prepare the workspace
- Set the
GOPATH
environment variable to your working directory. - Get the Google Calendar API Go client library and OAuth2 package using the following commands:
go get -u google.golang.org/api/calendar/v3
go get -u golang.org/x/oauth2/google
Step 2: Set up the sample
Create a file named quickstart.go
in your working directory and copy
in the following code:
Step 3: Run the sample
Build and run the sample using the following command from your working directory:
go run quickstart.go
The first time you run the sample, it prompts you to authorize access:
Browse to the provided URL in your web browser.
If you're not already signed in to your Google account, you're prompted to sign in. If you're signed in to multiple Google accounts, you are asked to select one account to use for authorization.
- Click the Accept button.
- Copy the code you're given, paste it into the command-line prompt, and press Enter.
Notes
- Authorization information is stored on the file system, so subsequent executions don't prompt for authorization.
- The authorization flow in this example is designed for a command-line application. For information on how to perform authorization in a web application, see Using OAuth 2.0 for Web Server Applications .
Troubleshooting
This section describes some common issues that you may encounter while attempting to run this quickstart and suggests possible solutions.
This app isn't verified
If the OAuth consent screen displays the warning "This app isn't verified," your app is requesting scopes that provide access to sensitive user data. If your application uses sensitive scopes, your app must go through the verification process to remove that warning and other limitations. During the development phase, you can continue past this warning by selecting Advanced > Go to {Project Name} (unsafe).
File not found error for credentials.json
When running the sample, you might receive a file not found or no such file error regarding credentials.json.
This error occurs when you have not authorized the desktop application credentials as detailed in the Prerequisites section above. To learn how to create credentials for a desktop application, go to Create credentials.
Once you create the credentials, make sure the downloaded JSON file is saved as
credentials.json
. Then move the file to your working directory with the rest of the
sample quickstart code.
Further reading
For further information on the APIs used in this quickstart, refer to the google-api-go-client section of GitHub.