TRACING-4069: Add docs for filelog receiver component

Signed-off-by: Ruben Vargas <[email protected]>

Author: rubenvp8510

modules/otel-collector-components.adoc

@@ -199,6 +199,32 @@ The OpenCensus receiver provides backwards compatibility with the OpenCensus pro
 Wildcards with `+*+` are accepted under the `cors_allowed_origins`.
 To match any origin, enter only `+*+`.
 
+[id="filelog-receiver_{context}"]
+=== Filelog Receiver
+
+:FeatureName: The Filelog Receiver
+include::snippets/technology-preview.adoc[]
+
+The Filelog Receiver tails and parses logs from files.
+
+.OpenTelemetry Collector custom resource with the enabled Filelog Receiver that tails a text file
+[source,yaml]
+----
+receivers:
+  filelog:
+    include: [ /simple.log ] # <1>
+    operators: # <2>
+      - type: regex_parser
+        regex: '^(?P<time>\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}) (?P<sev>[A-Z]*) (?P<msg>.*)$'
+        timestamp:
+          parse_from: attributes.time
+          layout: '%Y-%m-%d %H:%M:%S'
+        severity:
+          parse_from: attributes.sev
+----
+<1> A list of file glob patterns that match the file paths to be read.
+<2> An array of Operators. Each Operator performs a simple task such as parsing a timestamp or JSON. To process logs into a desired format, chain the Operators together.
+
 [id="processors_{context}"]
 == Processors