Updated readme, and added example gif

README.md

@@ -1,84 +1,91 @@
 # aws-oidc
 
-Assume roles in AWS using an OpenID Connect Identity provider.
+Assume roles in AWS using an OpenID Connect identity provider.
 
-It outputs temporary AWS credentials in a JSON format that can be consumed by the credentials_process setting in ~/.aws/config.
+![example](docs/aws-oidc-lambda.gif)
+
+It is intended to be used as a `credentials_process` in ~/.aws/config that outputs temporary AWS credentials in a JSON format.
 
 https://docs.aws.amazon.com/cli/latest/topic/config-vars.html#sourcing-credentials-from-external-processes
 
-Example:
+## Getting Started
 
-    aws-oidc auth \
-      --role_arn="arn:aws:iam::892845094662:role/onelogin-test-oidc" \
-      --duration=3600 \
-      --provider_url=https://openid-connect.onelogin.com/oidc \
-      --client_id=97a61160-3c09-0137-8c69-0a1c3f4fd822144813 \
-      --agent=open
+For example, add the following to **~/.aws/config**:
 
-All the provider arguments can be specified in a TOML configuration file:
+    [profile default]
+    credential_process = /Users/jeremy/projects/aws-oidc/aws-oidc auth google
+
+And configure aws-oidc by creating **~/.aws-oidc/config** and setting the `role_arn` and `client_id`:
 
     region = "ap-southeast-2"
 
-    [[AuthProvider]]
-    name = "onelogin"
-    role_arn = "arn:aws:iam::012345678901:role/role-name"
-    duration = 900
-    provider_url = "https://openid-connect.onelogin.com/oidc"
-    client_id = "ef061080-43aa-0137-62f3-066d8813aeb888900"
-    agent = ["open", "-b", "com.google.chrome", "-n", "--args", "--profile-directory=Default", "{}"]
-
     [[AuthProvider]]
     name = "google"
     role_arn = "arn:aws:iam::012345678901:role/role-name"
     duration = 900
     provider_url = "https://accounts.google.com"
     client_id = "430784603061-osbtei3s71l0bj6d8oegto0itefjmiq6.apps.googleusercontent.com"
+    agent = ["open", "-b", "com.google.chrome"]
+
+Then you can assume the role using the AWS cli:
+
+    aws sts get-caller-identity
+
+Most AWS SDK implementations should be able to use the `credential_process` configuration, including:
+
+* aws-sdk-go
+* aws-cli
+* boto3
+
+## Open Chrome with a particular profile
+
+Open `chrome://version/` in the Chrome profile you want to open as, and make a note of the last part of the profile path.
+
+Update the `agent` option with the profile path in your **~/.aws-oidc/config** file:
+
     agent = ["open", "-b", "com.google.chrome", "-n", "--args", "--profile-directory=Profile 1", "{}"]
 
-This configuration file should be located in **~/.aws-oidc/config**
-
-## Configure AWS Config
+## Configure More Roles
 
 Add the profiles for each role you want to assume to **~/.aws/config**. Specify the provider name from the configuration file, and override any default settings:
 
     [profile engineer]
     credential_process = aws-oidc auth onelogin --role_arn=arn:aws:iam::892845094662:role/onelogin-test-oidc --duration 7200
 
-Now you can use the AWS cli as normal, and specify the profile:
+Make sure each authentication provider exists in **~/.aws-oidc/config**. You can also override any of the configured settings here on the command line.
 
-    $ aws --profile engineer sts get-caller-identity
-    {
-        "UserId": "AROAJUTXNWXGCAEILMXTY:50904038",
-        "Account": "892845094662",
-        "Arn": "arn:aws:sts::892845094662:assumed-role/onelogin-test-oidc/50904038"
-    }
+To make use of this new role, simply specify the `profile` in your AWS SDK:
 
-## Run other commands with credentials
+    aws --profile engineer sts get-caller-identity
 
-Most AWS SDK's should be able to pick up the profile parameter, and suppor the `credentials_process` setting in your **~/.aws/config** file. If not, you can run an arbitary command with the temporary credentials with `exec`:
+## Run other commands with AWS credentials
+
+Most AWS SDK's should be able to pick up the profile parameter, and support the `credentials_process` setting in your **~/.aws/config** file. If not, you can run an arbitary command with the temporary credentials with `exec`:
 
     aws-oidc exec engineer -- ./path/to/command with arguments
 
-This will use the profiles defined in **~/.aws/config** to assume the role with `aws-oidc` and then set `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` environment variables for the new process.
+This will use the profiles defined in **~/.aws/config** to assume the role by calling `aws-oidc auth` and then set `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY` and `AWS_SESSION_TOKEN` environment variables for the new process.
 
 ## Find roles that an oidc client could assume
 
 Use the `list` command to find roles that your claim and client_id can assume:
 
-    aws-oidc list --claim="openid-connect.onelogin.com/oidc:aud" --client_id="ef061080-43aa-0137-62f3-066d8813aeb888900"
+    aws-oidc list --claim="accounts.google.com:aud" --client_id="430784603061-osbtei3s71l0bj6d8oegto0itefjmiq6.apps.googleusercontent.com"
 
 Example using only the AWS CLI:
 
     aws iam list-roles --query <<EOF '
     Roles[?
       AssumeRolePolicyDocument.Statement[?
-        Condition.StringEquals."openid-connect.onelogin.com/oidc:aud"
+        Condition.StringEquals."accounts.google.com:aud"
       ]
     ].{
       RoleName:RoleName,
       Arn:Arn,
-      ClientId:AssumeRolePolicyDocument.Statement[*].Condition.StringEquals."openid-connect.onelogin.com/oidc:aud" | [0]
+      ClientId:AssumeRolePolicyDocument.Statement[*].Condition.StringEquals."accounts.google.com:aud" | [0]
     } | [?
-      contains(ClientId, `ef061080-43aa-0137-62f3-066d8813aeb888900`)
+      contains(ClientId, `430784603061-osbtei3s71l0bj6d8oegto0itefjmiq6.apps.googleusercontent.com`)
     ]'
     EOF
+
+Note, your default profile will need `iam:ListRoles` permission. To use a different profile use the `--profile` option.