{"id":309,"date":"2025-11-01T04:05:10","date_gmt":"2025-11-01T04:05:10","guid":{"rendered":"https:\/\/mitalgoswami.in\/?p=309"},"modified":"2025-11-05T15:49:30","modified_gmt":"2025-11-05T15:49:30","slug":"what-is-mongodb-gridfs","status":"publish","type":"post","link":"https:\/\/mitalgoswami.in\/?p=309","title":{"rendered":"what is mongodb gridfs?"},"content":{"rendered":"\n

GridFS<\/strong> stands for Grid File System<\/strong>. MongoDB GridFS<\/strong> is a specification for storing and retrieving large files<\/strong> (such as images, videos, audio files, or any binary data) in MongoDB<\/strong> that exceed the BSON document size limit of 16 MB<\/strong>.<\/p>\n\n\n\n

How It Works<\/h3>\n\n\n\n

GridFS uses two collections<\/strong> to manage files:<\/p>\n\n\n\n

    \n
  1. fs.files<\/code><\/strong> \u2013 Stores file metadata such as filename, upload date, size, and a unique ID.<\/li>\n\n\n\n
  2. fs.chunks<\/code><\/strong> \u2013 Stores the actual file data in chunks, each linked to the parent file via an ObjectId.<\/li>\n<\/ol>\n\n\n\n

    Each chunk document in fs.chunks<\/code> looks like this:<\/p>\n\n\n\n

    {\n  \"_id\": ObjectId(\"...\"),\n  \"files_id\": ObjectId(\"...\"),  \/\/ reference to fs.files._id\n  \"n\": 0,                       \/\/ chunk sequence number\n  \"data\": BinData(...)           \/\/ binary data\n}\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
     Example Flow<\/h3>\n\n\n\n
      \n
    1. You upload a large file.<\/li>\n\n\n\n
    2. GridFS splits it into chunks (e.g., 255 KB each).<\/li>\n\n\n\n
    3. Each chunk is stored in fs.chunks<\/code>.<\/li>\n\n\n\n
    4. Metadata about the file (like name, length, and MD5 hash) goes into fs.files<\/code>.<\/li>\n\n\n\n
    5. When you download or read the file, GridFS reassembles it in order.<\/li>\n<\/ol>\n\n\n\n
      Tools & Drivers<\/h3>\n\n\n\n
      Most MongoDB drivers include built-in support for GridFS.
      For example:<\/p>\n\n\n\n
        \n
      • Node.js:<\/strong> GridFSBucket<\/code> API in the official mongodb<\/code> driver.<\/li>\n\n\n\n
      • Python:<\/strong> gridfs<\/code> module in pymongo<\/code>.<\/li>\n\n\n\n
      • Mongo Shell:<\/strong> Some tools like mongofiles<\/strong><\/code> let you work with GridFS directly.<\/li>\n<\/ul>\n\n\n\n
        How to Add (Upload) Images to GridFS Manually via Command Line<\/h2>\n\n\n\n
        MongoDB provides a built-in tool called mongofiles<\/code><\/strong> for working with GridFS from the terminal.<\/p>\n\n\n\n
        You can use it to upload, list, download, or delete files<\/strong> in GridFS \u2014 no programming needed.<\/p>\n\n\n\n
        \n\n\n\n
         Step-by-Step Example<\/h3>\n\n\n\n
        1. Make sure MongoDB is running<\/h4>\n\n\n\n
        If you\u2019re running MongoDB locally:<\/p>\n\n\n\n
        mongod\n<\/code><\/pre>\n\n\n\n
        2. Open another terminal window<\/h4>\n\n\n\n
        3. Use the mongofiles<\/code> tool<\/h4>\n\n\n\n
        Here\u2019s the syntax:<\/p>\n\n\n\n
        mongofiles --db <database_name> put <filename>\n<\/code><\/pre>\n\n\n\n
        \n\n\n\n
         Example \u2014 Upload an Image<\/h3>\n\n\n\n
        Suppose you have a file named photo.jpg<\/code><\/strong> in your current folder.<\/p>\n\n\n\n
        Run this command:<\/p>\n\n\n\n
        mongofiles --db=mydatabase put photo.jpg\n<\/code><\/pre>\n\n\n\n
        Explanation:<\/strong><\/p>\n\n\n\n
          \n
        • --db=mydatabase<\/code> \u2192 stores file in the mydatabase<\/code> database<\/li>\n\n\n\n
        • put photo.jpg<\/code> \u2192 uploads the file into GridFS<\/li>\n<\/ul>\n\n\n\n
          \n\n\n\n
           After Uploading<\/h3>\n\n\n\n
          If you open the MongoDB shell and connect to your database:<\/p>\n\n\n\n
          mongosh\nuse mydatabase\n<\/code><\/pre>\n\n\n\n
          Then check the collections:<\/p>\n\n\n\n
          show collections\n<\/code><\/pre>\n\n\n\n
          You\u2019ll see:<\/p>\n\n\n\n
          fs.files\nfs.chunks\n<\/code><\/pre>\n\n\n\n
          Now, you can inspect what\u2019s inside:<\/p>\n\n\n\n
          db.fs.files.find().pretty()\n<\/code><\/pre>\n\n\n\n
          You\u2019ll get something like:<\/p>\n\n\n\n
          {\n  \"_id\": ObjectId(\"654240f57b7d9e47f1fce9b2\"),\n  \"length\": 523424,\n  \"chunkSize\": 261120,\n  \"uploadDate\": ISODate(\"2025-11-01T12:00:00Z\"),\n  \"filename\": \"photo.jpg\"\n}\n<\/code><\/pre>\n\n\n\n
          And in fs.chunks<\/code>:<\/p>\n\n\n\n
          db.fs.chunks.find().limit(2).pretty()\n<\/code><\/pre>\n\n\n\n
          Each document looks like:<\/p>\n\n\n\n
          {\n  \"_id\": ObjectId(\"654240f57b7d9e47f1fce9b3\"),\n  \"files_id\": ObjectId(\"654240f57b7d9e47f1fce9b2\"),\n  \"n\": 0,\n  \"data\": BinData(0,\"\/9j\/4AAQSkZJRgABAQ...\")\n}\n<\/code><\/pre>\n\n\n\n
          \n\n\n\n
           To Download the Image Back<\/h3>\n\n\n\n
          If you want to download the file again from GridFS:<\/p>\n\n\n\n
          mongofiles --db=mydatabase get photo.jpg\n<\/code><\/pre>\n\n\n\n
          This will create a new file named photo.jpg<\/code> in your current folder.<\/p>\n\n\n\n
          \n\n\n\n
           To Delete the Image<\/h3>\n\n\n\n
          mongofiles --db=mydatabase delete photo.jpg<\/code><\/pre>\n\n\n\n
          Command<\/th>Action<\/th><\/tr><\/thead><\/table><\/figure>\n\n\n\n
          mongofiles --db=mydb put file.jpg<\/code><\/td>Upload (store in GridFS)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          mongofiles --db=mydb list<\/code><\/td>List all stored files<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          mongofiles --db=mydb get file.jpg<\/code><\/td>Download a file<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          mongofiles --db=mydb delete file.jpg<\/code><\/td>Delete a file<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
          Full Example Workflow<\/h2>\n\n\n\n
          Step 1 \u2014 Start MongoDB<\/h3>\n\n\n\n
          mongod --dbpath \"C:\\data\\db\"\n<\/code><\/pre>\n\n\n\n
          Step 2 \u2014 Upload a file<\/h3>\n\n\n\n
          mongofiles --db=test put 1.png\n<\/code><\/pre>\n\n\n\n
          Step 3 \u2014 List files in GridFS<\/h3>\n\n\n\n
          mongofiles --db=test list\n<\/code><\/pre>\n\n\n\n
          Step 4 \u2014 Download the file<\/h3>\n\n\n\n
          mongofiles --db=test get 1.png\n<\/code><\/pre>\n\n\n\n
          Step 5 \u2014 Delete it (optional)<\/h3>\n\n\n\n
          mongofiles --db=test delete 1.png<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
          GridFS stands for Grid File System. MongoDB GridFS is a specification for storing and retrieving large files (such as images, videos, audio files, or any binary data) in MongoDB that exceed the BSON document size limit of 16 MB. How It Works GridFS uses two collections to manage files: Each chunk document in fs.chunks looks […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-309","post","type-post","status-publish","format-standard","hentry","category-mongodb"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/309","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=309"}],"version-history":[{"count":2,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/309\/revisions"}],"predecessor-version":[{"id":312,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=\/wp\/v2\/posts\/309\/revisions\/312"}],"wp:attachment":[{"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=309"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=309"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mitalgoswami.in\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=309"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}