processor_content_modifier: update docs with recent updates

Signed-off-by: Eduardo Silva <[email protected]>

Author: edsiper

pipeline/processors/content-modifier.md

@@ -1,17 +1,43 @@
 # Content Modifier
 
-The **content_modifier** processor allows you to manipulate the metadata/attributes and content of Logs and Traces. 
+The **content_modifier** processor allows you to manipulate the messages, metadata/attributes and content of Logs and Traces.
 
 Similar to the functionality exposed by filters, this processor presents a unified mechanism to perform such operations for data manipulation. The most significant difference is that processors perform better than filters, and when chaining them, there are no encoding/decoding performance penalties.
 
 Note that processors and this specific component can only be enabled using the new YAML configuration format. Classic mode configuration format doesn't support processors.
 
+## Contexts
+
+The processor, works on top of what we call a __context__, meaning _the place_ where the content modification will happen. We provide different contexts to manipulate the desired information, the following contexts are available:
+
+| Context Name | Signal | Description |
+| -- | -- | -- |
+| `attributes` | Logs | Modify the attributes or metadata of a Log record. |
+| `body` | Logs | Modify the content of a Log record. |
+| `span_name` | Traces | Modify the name of a Span. |
+| `span_kind` | Traces | Modify the kind of a Span. |
+| `span_status` | Traces | Modify the status of a Span. |
+| `span_attributes` | Traces | Modify the attributes of a Span. |
+
+
+### OpenTelemetry Contexts
+
+In addition, we provide special contexts to operate on data that follows an __OpenTelemetry Log Schema__, all of them operates on shared data across a group of records:
+
+| Context Name | Signal | Description |
+| -- | -- | -- |
+| `otel_resource_attributes` | Logs | Modify the attributes of the Log Resource. |
+| `otel_scope_name` | Logs | Modify the name of a Log Scope. |
+| `otel_scope_version` | Logs | Modify version of a Log Scope. |
+| `otel_scope_attributes` | Logs | Modify the attributes of a Log Scope. |
+
+> TIP: if your data is not following the OpenTelemetry Log Schema and your backend or destination for your logs expects to be in an OpenTelemetry schema, take a look at the processor called OpenTelemetry Envelope that you can use in conjunbction with this processor to transform your data to be compatible with OpenTelemetry Log schema.
+
 ## Configuration Parameters
 
 | Key         | Description |
 | :---------- | :--- |
-| action | Define the operation to run on the target content. This field is mandatory; for more details about the actions available, check the table below. |
-| context | Specify which component of the Telemetry type will be affected. When processing Logs the following contexts are available:  `attributes`  or `body`. When processing Traces the following contexts are available: `span_name`, `span_kind`, `span_status`, `span_attributes`. |
+| context | Specify the context where the modifications will happen (more details above).The following contexts are available:  `attributes`, `body`, `span_name`, `span_kind`, `span_status`, `span_attributes`, `otel_resource_attributes`, `otel_scope_name`, `otel_scope_version`, `otel_scope_attributes`. |
 | key | Specify the name of the key that will be used to apply the modification. |
 | value | Based on the action type, `value` might required and represent different things. Check the detailed information for the specific actions. |
 | pattern | Defines a regular expression pattern. This property is only used by the `extract` action. |
@@ -23,13 +49,13 @@ The actions specify the type of operation to run on top of a specific key or con
 
 | Action  | Description                                                  |
 | ------- | ------------------------------------------------------------ |
-| insert  | Insert a new key with a value into the target context. The `key` and `value` parameters are required. |
-| upsert  | Given a specific key with a value, the `upsert` operation will try to update the value of the key. If the key does not exist, the key will be created. The `key` and `value` parameters are required. |
-| delete  | Delete a key from the target context. The `key` parameter is required. |
-| rename  | Change the name of a key. The `value` set in the configuration will represent the new name. The `key` and `value` parameters are required. |
-| hash    | Replace the key value with a hash generated by the SHA-256 algorithm, the binary value generated is finally set as an hex string representation. The `key` parameter is required. |
-| extract | Allows to extact the value of a single key as a list of key/value pairs. This action needs the configuration of a regular expression in the  `pattern` property . The `key` and `pattern` parameters are required.  For more details check the examples below. |
-| convert | Convert the data type of a key value. The `key` and `converted_type` parameters are required. |
+| `insert`  | Insert a new key with a value into the target context. The `key` and `value` parameters are required. |
+| `upsert`  | Given a specific key with a value, the `upsert` operation will try to update the value of the key. If the key does not exist, the key will be created. The `key` and `value` parameters are required. |
+| `delete`  | Delete a key from the target context. The `key` parameter is required. |
+| `rename`  | Change the name of a key. The `value` set in the configuration will represent the new name. The `key` and `value` parameters are required. |
+| `hash`    | Replace the key value with a hash generated by the SHA-256 algorithm, the binary value generated is finally set as an hex string representation. The `key` parameter is required. |
+| `extract` | Allows to extact the value of a single key as a list of key/value pairs. This action needs the configuration of a regular expression in the  `pattern` property . The `key` and `pattern` parameters are required.  For more details check the examples below. |
+| `convert` | Convert the data type of a key value. The `key` and `converted_type` parameters are required. |
 
 #### Insert example
 
@@ -74,7 +100,7 @@ pipeline:
             action: upsert
             key: "key2"
             value: "example"
-            
+
   outputs:
     - name : stdout
       match: '*'
@@ -97,8 +123,8 @@ pipeline:
         logs:
           - name: content_modifier
             action: delete
-            key: "key2"   
-         
+            key: "key2"
+
   outputs:
     - name : stdout
       match: '*'
@@ -168,7 +194,7 @@ pipeline:
             action: extract
             key: "http.url"
             pattern: ^(?<http_protocol>https?):\/\/(?<http_domain>[^\/\?]+)(?<http_path>\/[^?]*)?(?:\?(?<http_query_params>.*))?
-            
+
   outputs:
     - name : stdout
       match: '*'
@@ -198,7 +224,7 @@ pipeline:
             action: convert
             key: key2
             converted_type: boolean
-            
+
   outputs:
     - name : stdout
       match: '*'