README.md in embulk-output-redshift-0.7.1 vs README.md in embulk-output-redshift-0.7.2

@@ -16,12 +16,51 @@
 - **ssl**: use SSL to connect to the database (string, default: "disable". "enable" uses SSL without server-side validation and "verify" checks the certificate. For compatibility reasons, "true" behaves as "enable" and "false" behaves as "disable".)
 - **password**: database login password (string, default: "")
 - **database**: destination database name (string, required)
 - **schema**: destination schema name (string, default: "public")
 - **table**: destination table name (string, required)
-- **access_key_id**: access key id for AWS
-- **secret_access_key**: secret access key for AWS
+- **access_key_id**: deprecated. `aws_access_key_id` should be used (see "basic" in `aws_auth_method`).
+- **secret_access_key**: deprecated. `aws_secret_access_key` should be used (see "basic" in `aws_auth_method`).
+- **aws_auth_method**: name of mechanism to authenticate requests ("basic", "env", "instance", "profile", "properties", "anonymous", or "session". default: "basic")
+
+  - "basic": uses `access_key_id` and `secret_access_key` to authenticate.
+
+    - **aws_access_key_id**: AWS access key ID (string, required)
+
+    - **aws_secret_access_key**: AWS secret access key (string, required)
+
+  - "env": uses `AWS_ACCESS_KEY_ID` (or `AWS_ACCESS_KEY`) and `AWS_SECRET_KEY` (or `AWS_SECRET_ACCESS_KEY`) environment variables.
+
+  - "instance": uses EC2 instance profile.
+
+  - "profile": uses credentials written in a file. Format of the file is as following, where `[...]` is a name of profile.
+
+    - **aws_profile_file**: path to a profiles file. (string, default: given by `AWS_CREDENTIAL_PROFILES_FILE` environment varialbe, or ~/.aws/credentials).
+
+    - **aws_profile_name**: name of a profile. (string, default: `"default"`)
+
+    ```
+    [default]
+    aws_access_key_id=YOUR_ACCESS_KEY_ID
+    aws_secret_access_key=YOUR_SECRET_ACCESS_KEY
+
+    [profile2]
+    ...
+    ```
+
+  - "properties": uses `aws.accessKeyId` and `aws.secretKey` Java system properties.
+
+  - "anonymous": uses anonymous access. This authentication method can access only public files.
+
+  - "session": uses temporary-generated `access_key_id`, `secret_access_key` and `session_token`.
+
+    - **aws_access_key_id**: AWS access key ID (string, required)
+
+    - **aws_secret_access_key**: AWS secret access key (string, required)
+
+    - **aws_session_token**: session token (string, required)
+
 - **iam_user_name**: IAM user name for uploading temporary files to S3. The user should have permissions of `s3:GetObject`, `s3:PutObject`, `s3:DeleteObject`, `s3:ListBucket` and `sts:GetFederationToken`. And furthermore, the user should have permission of `s3:GetBucketLocation` if Redshift region and S3 bucket region are different. (string, default: "", but we strongly recommend that you use IAM user for security reasons. see below.)
 - **s3_bucket**: S3 bucket name for temporary files
 - **s3_key_prefix**: S3 key prefix for temporary files (string, default:"")
 - **options**: extra connection properties (hash, default: {})
 - **retry_limit** max retry count for database operations (integer, default: 12)
@@ -87,12 +126,12 @@
   host: myinstance.us-west-2.redshift.amazonaws.com
   user: pg
   password: ""
   database: my_database
   table: my_table
-  access_key_id: ABCXYZ123ABCXYZ123
-  secret_access_key: AbCxYz123aBcXyZ123
+  aws_access_key_id: ABCXYZ123ABCXYZ123
+  aws_secret_access_key: AbCxYz123aBcXyZ123
   iam_user_name: my-s3-read-only
   s3_bucket: my-redshift-transfer-bucket
   s3_key_prefix: temp/redshift
   mode: insert
 ```
@@ -106,21 +145,53 @@
   user: pg
   ssl: enable
   password: ""
   database: my_database
   table: my_table
-  access_key_id: ABCXYZ123ABCXYZ123
-  secret_access_key: AbCxYz123aBcXyZ123
+  aws_access_key_id: ABCXYZ123ABCXYZ123
+  aws_secret_access_key: AbCxYz123aBcXyZ123
   iam_user_name: my-s3-read-only
   s3_bucket: my-redshift-transfer-bucket
   s3_key_prefix: temp/redshift
   options: {loglevel: 2}
   mode: insert_direct
   column_options:
     my_col_1: {type: 'VARCHAR(255)'}
     my_col_3: {type: 'INT NOT NULL'}
     my_col_4: {value_type: string, timestamp_format: `%Y-%m-%d %H:%M:%S %z`, timezone: '-0700'}
     my_col_5: {type: 'DECIMAL(18,9)', value_type: pass}
+```
+
+To use IAM Role:
+
+```yaml
+out:
+  type: redshift
+  host: myinstance.us-west-2.redshift.amazonaws.com
+  user: pg
+  password: ""
+  database: my_database
+  table: my_table
+  s3_bucket: my-redshift-transfer-bucket
+  s3_key_prefix: temp/redshift
+  mode: insert
+  aws_auth_method: instance
+```
+
+To use AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables:
+
+```yaml
+out:
+  type: redshift
+  host: myinstance.us-west-2.redshift.amazonaws.com
+  user: pg
+  password: ""
+  database: my_database
+  table: my_table
+  s3_bucket: my-redshift-transfer-bucket
+  s3_key_prefix: temp/redshift
+  mode: insert
+  aws_auth_method: env
 ```
 
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