Add scraper for logs (#11799)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description
Add scraper for logs

<!-- Issue number if applicable -->
#### Link to tracking issue
Relates to #11238 

<!--Describe what testing was performed and which tests were added.-->
#### Testing
Added unit tests

<!--Describe the documentation added.-->
#### Documentation
Added

<!--Please delete paragraphs that you did not use before submitting.-->

Author: sincejune

.chloggen/add-scraper-for-logs.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: receiver/scraperhelper
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Add scraper for logs
+
+# One or more tracking issues or pull requests related to the change
+issues: [11238]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [api]

scraper/README.md

@@ -5,8 +5,8 @@ A scraper defines how to connect and scrape telemetry data from an external sour
 <!-- status autogenerated section -->
 | Status        |           |
 | ------------- |-----------|
-| Stability     | [development]: metrics   |
+| Stability     | [development]: metrics, logs   |
 | Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector?query=is%3Aissue%20is%3Aopen%20label%3Apkg%2F%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector/issues?q=is%3Aopen+is%3Aissue+label%3Apkg%2F) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector?query=is%3Aissue%20is%3Aclosed%20label%3Apkg%2F%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector/issues?q=is%3Aclosed+is%3Aissue+label%3Apkg%2F) |
 
 [development]: https://github.com/open-telemetry/opentelemetry-collector/blob/main/docs/component-stability.md#development
-<!-- end autogenerated section -->
+<!-- end autogenerated section -->

scraper/logs.go

@@ -0,0 +1,44 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package scraper // import "go.opentelemetry.io/collector/scraper"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/pdata/plog"
+)
+
+// Logs is the base interface for logs scrapers.
+type Logs interface {
+	component.Component
+
+	// ScrapeLogs is the base interface to indicate that how should logs be scraped.
+	ScrapeLogs(context.Context) (plog.Logs, error)
+}
+
+// ScrapeLogsFunc is a helper function that is similar to Logs.ScrapeLogs.
+type ScrapeLogsFunc ScrapeFunc[plog.Logs]
+
+func (sf ScrapeLogsFunc) ScrapeLogs(ctx context.Context) (plog.Logs, error) {
+	return sf(ctx)
+}
+
+type logs struct {
+	baseScraper
+	ScrapeLogsFunc
+}
+
+// NewLogs creates a new Logs scraper.
+func NewLogs(scrape ScrapeLogsFunc, options ...Option) (Logs, error) {
+	if scrape == nil {
+		return nil, errNilFunc
+	}
+	bs := &logs{
+		baseScraper:    newBaseScraper(options),
+		ScrapeLogsFunc: scrape,
+	}
+
+	return bs, nil
+}

scraper/logs_test.go

@@ -0,0 +1,79 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package scraper
+
+import (
+	"context"
+	"errors"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/component/componenttest"
+	"go.opentelemetry.io/collector/pdata/plog"
+)
+
+func TestNewLogs(t *testing.T) {
+	mp, err := NewLogs(newTestScrapeLogsFunc(nil))
+	require.NoError(t, err)
+
+	require.NoError(t, mp.Start(context.Background(), componenttest.NewNopHost()))
+	md, err := mp.ScrapeLogs(context.Background())
+	require.NoError(t, err)
+	assert.Equal(t, plog.NewLogs(), md)
+	require.NoError(t, mp.Shutdown(context.Background()))
+}
+
+func TestNewLogs_WithOptions(t *testing.T) {
+	want := errors.New("my_error")
+	mp, err := NewLogs(newTestScrapeLogsFunc(nil),
+		WithStart(func(context.Context, component.Host) error { return want }),
+		WithShutdown(func(context.Context) error { return want }))
+	require.NoError(t, err)
+
+	assert.Equal(t, want, mp.Start(context.Background(), componenttest.NewNopHost()))
+	assert.Equal(t, want, mp.Shutdown(context.Background()))
+}
+
+func TestNewLogs_NilRequiredFields(t *testing.T) {
+	_, err := NewLogs(nil)
+	require.Error(t, err)
+}
+
+func TestNewLogs_ProcessLogsError(t *testing.T) {
+	want := errors.New("my_error")
+	mp, err := NewLogs(newTestScrapeLogsFunc(want))
+	require.NoError(t, err)
+	_, err = mp.ScrapeLogs(context.Background())
+	require.ErrorIs(t, err, want)
+}
+
+func TestLogsConcurrency(t *testing.T) {
+	mp, err := NewLogs(newTestScrapeLogsFunc(nil))
+	require.NoError(t, err)
+	require.NoError(t, mp.Start(context.Background(), componenttest.NewNopHost()))
+
+	var wg sync.WaitGroup
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			for j := 0; j < 10000; j++ {
+				_, errScrape := mp.ScrapeLogs(context.Background())
+				assert.NoError(t, errScrape)
+			}
+		}()
+	}
+	wg.Wait()
+	require.NoError(t, mp.Shutdown(context.Background()))
+}
+
+func newTestScrapeLogsFunc(retError error) ScrapeLogsFunc {
+	return func(_ context.Context) (plog.Logs, error) {
+		return plog.NewLogs(), retError
+	}
+}

scraper/metadata.yaml

@@ -4,4 +4,4 @@ github_project: open-telemetry/opentelemetry-collector
 status:
   class: pkg
   stability:
-    development: [metrics]
+    development: [metrics, logs]

scraper/scraper.go

@@ -12,7 +12,7 @@ import (
 
 var errNilFunc = errors.New("nil scrape func")
 
-// ScrapeFunc scrapes metrics.
+// ScrapeFunc scrapes data.
 type ScrapeFunc[T any] func(context.Context) (T, error)
 
 // Option apply changes to internal options.

scraper/scrapererror/partialscrapeerror.go

@@ -6,13 +6,13 @@ package scrapererror // import "go.opentelemetry.io/collector/scraper/scrapererr
 import "errors"
 
 // PartialScrapeError is an error to represent
-// that a subset of metrics were failed to be scraped.
+// that a subset of data were failed to be scraped.
 type PartialScrapeError struct {
 	error
 	Failed int
 }
 
-// NewPartialScrapeError creates PartialScrapeError for failed metrics.
+// NewPartialScrapeError creates PartialScrapeError for failed data.
 // Use this error type only when a subset of data was failed to be scraped.
 func NewPartialScrapeError(err error, failed int) PartialScrapeError {
 	return PartialScrapeError{