mongoimport option --dir to load a folder full of JSON files

CONTRIBUTING.md

@@ -92,6 +92,12 @@ Example of how to run a specific integration test:
 TOOLS_TESTING_INTEGRATION=true go test -v ./... -run TestImportDocuments
 ```
 
+To run the directory-import integration test (added for the `--dir` option):
+
+```
+TOOLS_TESTING_INTEGRATION=true go test -v ./mongoimport -run TestImportFromDirectory
+```
+
 To run the quality assurance tests, you need to have the latest stable version of the rebuilt tools,
 `mongod`, `mongos`, and `mongo` in your current working directory.
 

mongoimport/dir_test.go

@@ -0,0 +1,87 @@
+// Copyright (C) MongoDB, Inc. 2014-present.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may
+// not use this file except in compliance with the License. You may obtain
+// a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+
+package mongoimport
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/mongodb/mongo-tools/common/testtype"
+	"github.com/mongodb/mongo-tools/common/testutil"
+	"github.com/stretchr/testify/require"
+	"go.mongodb.org/mongo-driver/bson"
+)
+
+func TestGetJSONFilesFromDirUnit(t *testing.T) {
+	testtype.SkipUnlessTestType(t, testtype.UnitTestType)
+	require := require.New(t)
+
+	dir, cleanup := testutil.MakeTempDir(t)
+	defer cleanup()
+
+	require.NoError(os.WriteFile(filepath.Join(dir, "a.json"), []byte("{}"), 0o644))
+	require.NoError(os.WriteFile(filepath.Join(dir, "b.JSON"), []byte("{}"), 0o644))
+	require.NoError(os.WriteFile(filepath.Join(dir, "c.txt"), []byte("not json"), 0o644))
+
+	imp := NewMockMongoImport()
+	files, err := imp.getJSONFilesFromDir(dir)
+	require.NoError(err)
+
+	found := map[string]bool{}
+	for _, f := range files {
+		found[filepath.Base(f)] = true
+	}
+	require.True(found["a.json"])
+	require.True(found["b.JSON"])
+	require.False(found["c.txt"])
+}
+
+func TestGetJSONFilesFromDirNoJSONUnit(t *testing.T) {
+	testtype.SkipUnlessTestType(t, testtype.UnitTestType)
+	require := require.New(t)
+
+	dir, cleanup := testutil.MakeTempDir(t)
+	defer cleanup()
+
+	require.NoError(os.WriteFile(filepath.Join(dir, "only.txt"), []byte("no json here"), 0o644))
+
+	imp := NewMockMongoImport()
+	_, err := imp.getJSONFilesFromDir(dir)
+	require.Error(err)
+	require.Contains(err.Error(), "no JSON files found in directory")
+}
+
+func TestImportFromDirectoryIntegration(t *testing.T) {
+	testtype.SkipUnlessTestType(t, testtype.IntegrationTestType)
+	require := require.New(t)
+
+	dir, cleanup := testutil.MakeTempDir(t)
+	defer cleanup()
+
+	// Create two files with three documents total
+	require.NoError(os.WriteFile(filepath.Join(dir, "f1.json"), []byte("{"+"\"_id\":1,\"a\":1}\n{"+"\"_id\":2,\"a\":2}\n"), 0o644))
+	require.NoError(os.WriteFile(filepath.Join(dir, "f2.json"), []byte("{"+"\"_id\":3,\"a\":3}\n"), 0o644))
+
+	imp, err := getImportWithArgs("--dir", dir)
+	require.NoError(err)
+
+	imp.IngestOptions.Mode = modeInsert
+	imp.IngestOptions.WriteConcern = "majority"
+
+	numProcessed, numFailed, err := imp.ImportDocuments()
+	require.NoError(err)
+	require.Equal(uint64(3), numProcessed)
+	require.Equal(uint64(0), numFailed)
+
+	expectedDocuments := []bson.M{
+		{"_id": int32(1), "a": int32(1)},
+		{"_id": int32(2), "a": int32(2)},
+		{"_id": int32(3), "a": int32(3)},
+	}
+	require.NoError(checkOnlyHasDocuments(imp.SessionProvider, expectedDocuments))
+}