Fix bundle library doc to reflect new changes/features

Signed-off-by: Vu Dinh <[email protected]>

Author: dinhxuanvu

docs/design/operator-bundle.md

@@ -1,4 +1,4 @@
-# Operator Bundle
+overwrite# Operator Bundle
 
 An `Operator Bundle` is a container image that stores Kubernetes manifests and metadata associated with an operator. A bundle is meant to present a *specific* version of an operator.
 
@@ -87,7 +87,7 @@ In order to use Operator SDK CLI, follow the operator-SDK installation instructi
 
 1. Install the [Operator SDK CLI](https://github.com/operator-framework/operator-sdk/blob/master/doc/user/install-operator-sdk.md)
 
-Now, a binary named `operator-cli` is available in OLM's directory to use.
+Now, a binary named `operator-sdk` is available in OLM's directory to use.
 ```bash
 $ ./operator-sdk
 An SDK for building operators with ease
@@ -106,11 +106,29 @@ Use "operator-sdk [command] --help" for more information about a command.
 ```
 
 ### Generate Bundle Annotations and DockerFile
+*Notes:*
+* If there are `annotations.yaml` and `Dockerfile` existing in the directory, they will be overwritten.
 
-Using `operator-sdk` CLI, bundle annotations can be generated from provided operator manifests. The command for `generate` task is:
+Using `operator-sdk` CLI, bundle annotations can be generated from provided operator manifests. The overall `bundle generate` command usage is:
 ```bash
-$ ./operator-sdk bundle generate --directory /test/
+Usage:
+  operator-sdk bundle generate [flags]
+
+Flags:
+  -c, --channels string    The list of channels that bundle image belongs to
+  -e, --default string     The default channel for the bundle image
+  -d, --directory string   The directory where bundle manifests are located.
+  -h, --help               help for generate
+  -p, --package string     The name of the package that bundle image belongs to
 ```
+
+The `--directory/-d`, `--channels/-c`, `--package/-p` are required flags while `--default/-e` is optional.
+
+The command for `generate` task is:
+```bash
+$ ./operator-sdk bundle generate --directory /test --package test-operator --channels stable,beta --default stable
+```
+
 The `--directory` or `-d` specifies the directory where the operator manifests are located. The `Dockerfile` is generated in the same directory where the YAML manifests are located while the `annotations.yaml` file is located in a folder named `metadata`. For example:
 ```bash
 $ tree test
@@ -124,22 +142,43 @@ test
 └── Dockerfile
 ```
 
-*Notes:*
-* If there are `annotations.yaml` and `Dockerfile` existing in the directory, they will be overwritten.
+The `--package` or `-p` is the name of package fo the operator such as `etcd` which which map `channels` to a particular application definition. `channels` allow package authors to write different upgrade paths for different users (e.g. `beta` vs. `stable`). The `channels` list is provided via `--channels` or `-c` flag. Multiple `channels` are separated by a comma (`,`). The default channel is provided optionally via `--default` or `-e` flag. If the default channel is not provided, the first channel in channel list is selected as default.
+
+All information in `annotations.yaml` is also existed in `LABEL` section of `Dockerfile`.
 
 ### Build Bundle Image
 
-Operator bundle image can be built from provided operator manifests using `build` command:
+Operator bundle image can be built from provided operator manifests using `build` command (see *Notes* below). The overall `bundle build` command usage is:
 ```bash
-$ ./operator-sdk bundle build --directory /test/0.1.0/ --tag quay.io/coreos/test-operator.v0.1.0:latest
+Usage:
+  operator-SDK bundle build [flags]
+
+Flags:
+  -c, --channels string        The list of channels that bundle image belongs to
+  -e, --default string         The default channel for the bundle image
+  -d, --directory string       The directory where bundle manifests are located
+  -h, --help                   help for build
+  -b, --image-builder string   Tool to build container images. One of: [docker, podman, buildah] (default "docker")
+  -0, --overwrite               To overwrite annotations.yaml if existing
+  -p, --package string         The name of the package that bundle image belongs to
+  -t, --tag string             The name of the bundle image will be built
 ```
+
+The command for `build` task is:
+```bash
+$ ./operator-sdk bundle build --directory /test --tag quay.io/coreos/test-operator.v0.1.0:latest --package test-operator --channels stable,beta --default stable
+```
+
 The `--directory` or `-d` specifies the directory where the operator manifests are located. The `--tag` or `-t` specifies the image tag that you want the operator bundle image to have. By using `build` command, the `annotations.yaml` and `Dockerfile` are automatically generated in the background.
 
 The default image builder is `Docker`. However, ` Buildah` and `Podman` are also supported. An image builder can specified via `--image-builder` or `-b` optional tag in `build` command. For example:
 ```bash
-$ ./operator-sdk bundle build --directory /test/0.1.0/ --tag quay.io/coreos/test-operator.v0.1.0:latest --image-builder podman
+$ ./operator-sdk bundle build --directory /test/0.1.0/ --tag quay.io/coreos/test-operator.v0.1.0:latest --image-builder podman --package test-operator --channels stable,beta --default stable
 ```
 
+The `--package` or `-p` is the name of package fo the operator such as `etcd` which which map `channels` to a particular application definition. `channels` allow package authors to write different upgrade paths for different users (e.g. `beta` vs. `stable`). The `channels` list is provided via `--channels` or `-c` flag. Multiple `channels` are separated by a comma (`,`). The default channel is provided optionally via `--default` or `-e` flag. If the default channel is not provided, the first channel in channel list is selected as default.
+
 *Notes:*
-* If there are `annotations.yaml` and `Dockerfile` existing in the directory, they will be overwritten.
-* The directory where the operator manifests are located must must be inside the context of the build which in this case is inside the directory where you run the command.
+* If there is `Dockerfile` existing in the directory, it will be overwritten.
+* If there is an existing `annotations.yaml` in `/metadata` directory, the cli will attempt to validate it and returns any found errors. If the ``annotations.yaml`` is valid, it will be used as a part of build process. The optional boolean `--overwrite/-o` flag can be enabled (false by default) to allow cli to overwrite the `annotations.yaml` if existed.
+* The directory where the operator manifests are located must be inside the context of the build which in this case is inside the directory where you run the command.