docs: add individual release instructions (#902)

* docs: add single component release instructions

* fix: headers level

* docs: clarify repo-wide release tag

Author: rogercoll

README.md

@@ -2,6 +2,8 @@
 
 OpenTelemetry Collector Components is a collection of components of the [OpenTelemetry Collector](https://opentelemetry.io/docs/collector/) that were created at [Elastic](https://www.elastic.co/).
 
+For details on how to release individual or all components, see the [release documentation](./docs/release.md).
+
 ## Code of Conduct
 
 See [CODE_OF_CONDUCT](CODE_OF_CONDUCT.md).
@@ -14,24 +16,24 @@ This software is licensed under the [Apache 2 license](LICENSE).
 
 In order to build a collector with a custom component, e.g. for testing purposes, follow these steps:
 1. Edit the [manifest.yaml](distributions/elastic-components/manifest.yaml) file:
-   - Add the component you want to test to the proper component section. For  example, if you are testing a processor, add it to the 
+   - Add the component you want to test to the proper component section. For  example, if you are testing a processor, add it to the
      `processors` section.
-   - If you are testing a non-published version of the component, add an entry to the `replace` section, pointing to the local path of 
+   - If you are testing a non-published version of the component, add an entry to the `replace` section, pointing to the local path of
      the component's source.
-2. Build the collector through the `genelasticcol` target of the root [Makefile](Makefile). 
+2. Build the collector through the `genelasticcol` target of the root [Makefile](Makefile).
    Make sure to provide `TARGET_GOOS` and/or `TARGET_GOARCH` environment variables if you are building for a different platform.
-   For example, when building on macOS in order to run through the Linux Docker image that is built by the `builddocker` make target 
+   For example, when building on macOS in order to run through the Linux Docker image that is built by the `builddocker` make target
    (see next bullet) - use the following command:
    ```shell
    TARGET_GOOS=linux CGO_ENABLED=0 make genelasticcol
    ```
    The resulting binary will be placed in the `_build` directory.
-3. In order to build a Docker image with the collector, run the `builddocker` target of the root [Makefile](Makefile). 
+3. In order to build a Docker image with the collector, run the `builddocker` target of the root [Makefile](Makefile).
    This target requires the environment variable `TAG` to be set. The resulting image will be tagged as `elastic-collector-components:<TAG>`.
    You may also specify the `USERNAME` environment variable to name the image as `<USERNAME>/elastic-collector-components:<TAG>`. For example:
    ```shell
    make builddocker TAG=v0.1.0 USERNAME=johndoe
-   ``` 
+   ```
 
 ## Load generator
 

docs/release.md

@@ -1,6 +1,26 @@
 # Releasing opentelemetry-collector-components
 
-## Optional steps
+## Single component
+
+Single components should only be released independently when there is a bug fix or new feature that needs to be shipped for that specific component, without waiting for a full repository release.
+
+To release a single component:
+
+1. Identify the component path — for example: `processor/ratelimitprocessor`
+2. Check the latest released tag for that component (e.g. `processor/ratelimitprocessor/v0.1.0`).
+3. Decide the next version:
+ - Use a patch version bump for bug fixes (v0.1.1 → v0.1.2).
+ - Use a minor version bump for new features (v0.1.1 → v0.2.0).
+4. Create a new tag following the Go module path naming convention, either:
+ - Via GitHub UI: Go to Releases → Draft a new release, select or create the new tag (e.g. `processor/ratelimit/v0.2.0`), and publish it.
+ - Via Git CLI
+
+## All repository components
+
+All components in the repository can be released together as part of a coordinated release.
+The process for releasing all components is described in the section below.
+
+### (Optional) Updating upstream OTel dependencies
 
 Normally the following steps are not required for releasing the components. The update of otel based on upstream
 is automated and should not be performed manually unless there are specific reasons for this.
@@ -19,13 +39,15 @@ is automated and should not be performed manually unless there are specific reas
    - Open the PR
      🛑 **Do not move forward until this PR is merged.** 🛑
 
-## Create the new tags
+### Create the new tags
 
-2. Bump up the `module-sets.edit-base.version` in `versions.yaml` i.e. from `v0.20.0` to `v0.21.0`
+2. Decide the next version:
+   - 🛑 **Cross-check the [repository tags](https://github.com/elastic/opentelemetry-collector-components/tags) against the modules defined in [versions.yaml](../versions.yaml). Identify the highest version number currently in use.** 🛑
+   - The next version should be a **minor update** of the highest existing tag (i.e. processor/ratelimitprocessor/v0.20.1 → v0.21.0).
 
-    🛑 **Cross check latest version used by [EDOT](https://github.com/elastic/elastic-agent/blob/main/internal/pkg/otel/README.md?plain=1#L30) and https://github.com/elastic/opentelemetry-collector-components/tags** 🛑
+3. Bump up the `module-sets.edit-base.version` in `versions.yaml` i.e. from `v0.20.0` to `v0.21.0`
 
-3. Tag the module groups with the new release version by running:
+4. Tag the module groups with the new release version by running:
 
    ⚠️ If you set your remote using `https`, you need to
       include `REMOTE=https://github.com/elastic/opentelemetry-collector-components.git` in each command. ⚠️
@@ -48,5 +70,5 @@ is automated and should not be performed manually unless there are specific reas
    make push-tags
    ```
 
-4. Last step is to commit the change of `module-sets.edit-base.version` in `versions.yaml` and push it so as to store
+5. Last step is to commit the change of `module-sets.edit-base.version` in `versions.yaml` and push it so as to store
    the new latest version.