feat: add tesseract image loader

examples/loader/tesseract/main.go

@@ -0,0 +1,21 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/henomis/lingoose/loader"
+)
+
+func main() {
+
+	l := loader.NewTesseractLoader("/tmp/image.png")
+
+	docs, err := l.Load(context.Background())
+	if err != nil {
+		panic(err)
+	}
+
+	fmt.Println(docs[0].Content)
+
+}

loader/tesseract.go

@@ -0,0 +1,91 @@
+package loader
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+
+	"github.com/henomis/lingoose/document"
+	"github.com/henomis/lingoose/types"
+)
+
+var (
+	ErrTesseractNotFound = fmt.Errorf("pdftotext not found")
+	defaultTesseractPath = "/usr/bin/tesseract"
+)
+
+type tesseractLoader struct {
+	loader loader
+
+	tesseractPath string
+	tesseractArgs []string
+	filename      string
+}
+
+func NewTesseractLoader(filename string) *tesseractLoader {
+	return &tesseractLoader{
+		tesseractPath: defaultTesseractPath,
+		tesseractArgs: []string{},
+		filename:      filename,
+	}
+}
+
+func (l *tesseractLoader) WithTesseractPath(tesseractPath string) *tesseractLoader {
+	l.tesseractPath = tesseractPath
+	return l
+}
+
+func (l *tesseractLoader) WithTextSplitter(textSplitter TextSplitter) *tesseractLoader {
+	l.loader.textSplitter = textSplitter
+	return l
+}
+
+func (l *tesseractLoader) WithArgs(tesseractArgs []string) *tesseractLoader {
+	l.tesseractArgs = tesseractArgs
+	return l
+}
+
+func (l *tesseractLoader) Load(ctx context.Context) ([]document.Document, error) {
+
+	err := isFile(l.tesseractPath)
+	if err != nil {
+		return nil, ErrTesseractNotFound
+	}
+
+	err = isFile(l.filename)
+	if err != nil {
+		return nil, err
+	}
+
+	documents, err := l.loadFile(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	if l.loader.textSplitter != nil {
+		documents = l.loader.textSplitter.SplitDocuments(documents)
+	}
+
+	return documents, nil
+}
+
+func (l *tesseractLoader) loadFile(ctx context.Context) ([]document.Document, error) {
+
+	tesseractArgs := []string{l.filename, "stdout"}
+	tesseractArgs = append(tesseractArgs, l.tesseractArgs...)
+
+	out, err := exec.CommandContext(ctx, l.tesseractPath, tesseractArgs...).Output()
+	if err != nil {
+		return nil, err
+	}
+
+	metadata := make(types.Meta)
+	metadata[SourceMetadataKey] = l.filename
+
+	return []document.Document{
+		{
+			Content:  string(out),
+			Metadata: metadata,
+		},
+	}, nil
+}