retrieving file from S3 and retunr presignd url to the user

app/main/download_data.py

@@ -1,5 +1,6 @@
 import io
 import json
+from collections import namedtuple
 from datetime import datetime
 from enum import StrEnum
 from typing import Any
@@ -243,23 +244,80 @@ def process_api_response(query_params: dict) -> tuple:
 
 
 def process_async_download(query_params: dict):
+    """process async download request to start the background process.
+    :param query_params: (dict): Query parameters for the API request.
+    """
     request_url = (
         Config.DATA_STORE_API_HOST
         + "/trigger_async_download"
         + ("?" + urlencode(query_params, doseq=True) if query_params else "")
     )
-    requests.get(request_url)
+    requests.post(request_url, timeout=20)
 
 
-def retrieve_download_file(UUID: str):
-    if not UUID:
-        raise ValueError("UUID parameter is required")
+def get_presigned_url(filename: str):
+    """Get the presigned link for the short time to retrieve the file from s3 bucket.
+    :param filename (str): object name which needs to be retrieved from s3 if exists
+    Raises:ValueError: If object doest not exists in S3, it will raise an error.
+    Returns:Returns the response the API.
+    """
+    if not filename:
+        raise ValueError("filename is required")
 
-    response = get_response(Config.DATA_STORE_API_HOST, f"/retrieve-download/{UUID}")
+    response = get_response(Config.DATA_STORE_API_HOST, f"/get-presigned-url/{filename}")
+    return response
 
-    # if content_type == MIMETYPE.JSON:
-    #     file_content = io.BytesIO(json.dumps(response.json()).encode("UTF-8"))
-    # elif content_type == MIMETYPE.XLSX:
-    #     file_content = io.BytesIO(response.content)
 
-    return response
+FileMetadata = namedtuple("FileMetadata", ["last_modified_date", "file_format", "file_size_str"])
+
+
+def get_find_download_file_metadata(filename: str) -> FileMetadata:
+    """To get the object metadata from S3 using the ovject Key
+    :param filename (str): object name to get the metadata
+
+    Raises:
+        ValueError: If object doest not exists in S3, it will raise an error.
+
+    Returns: FileMetadata:
+             - Returns the last modified date,
+             -file format, and human-readable file size.
+    """
+    if not filename:
+        raise ValueError("filename is required")
+
+    try:
+        response = get_response(Config.DATA_STORE_API_HOST, f"/get-find-download-metadata/{filename}")
+        print(response.status_code)
+        metadata = response.json()
+        file_size = metadata["ContentLength"]
+        file_size_str = get_human_readable_file_size(file_size)
+        last_modified_date = metadata["LastModified"]
+        content_type = metadata["ContentType"]
+        file_format = ""
+
+        if content_type == MIMETYPE.XLSX:
+            file_format = "Microsoft Excel spreadsheet"
+        elif content_type == MIMETYPE.JSON:
+            file_format = "JSON"
+        else:
+            file_format = "Unknown type"
+
+        return FileMetadata(last_modified_date, file_format, file_size_str)
+
+    except requests.exceptions.RequestException as req_err:
+        raise RuntimeError(f"Request error when getting find file metadata: {req_err}") from req_err
+
+
+def get_human_readable_file_size(file_size_bytes: int) -> str:
+    """Return a human-readable file size string.
+    :param file_size_bytes: file size in bytes,
+    :return: human-readable file size,
+    """
+
+    file_size_kb = round(file_size_bytes / 1024, 1)
+    if file_size_kb < 1024:
+        return f"{round(file_size_kb, 1)} KB"
+    elif file_size_kb < 1024 * 1024:
+        return f"{round(file_size_kb / 1024, 1)} MB"
+    else:
+        return f"{round(file_size_kb / (1024 * 1024), 1)} GB"

app/main/forms.py

@@ -37,4 +37,4 @@ class DownloadForm(FlaskForm):
 
 
 class RetrieveForm(FlaskForm):
-    download = SubmitField("Download Your Data")
+    download = SubmitField("Download Your Data", widget=GovSubmitInput())

app/main/routes.py

@@ -10,7 +10,6 @@
     current_app,
     g,
     jsonify,
-    Response,
 )
 
 # isort: on
@@ -19,19 +18,19 @@
 from fsd_utils.authentication.decorators import login_requested, login_required
 from werkzeug.exceptions import HTTPException
 
-from app.const import MIMETYPE
 from app.main import bp
 from app.main.download_data import (
     FormNames,
     financial_quarter_from_mapping,
     financial_quarter_to_mapping,
+    get_find_download_file_metadata,
     get_fund_checkboxes,
     get_org_checkboxes,
     get_outcome_checkboxes,
+    get_presigned_url,
     get_region_checkboxes,
     get_returns,
     process_async_download,
-    retrieve_download_file,
 )
 from app.main.forms import DownloadForm, RetrieveForm
 
@@ -131,47 +130,43 @@ def request_received():
     return render_template("request-received.html", user_email=g.user.email)
 
 
-@bp.route("/retrieve-download/<UUID>", methods=["GET", "POST"])
+@bp.route("/get-presigned-url/<filename>", methods=["GET", "POST"])
 @login_required(return_app=SupportedApp.POST_AWARD_FRONTEND)
-def retrieve_download(UUID: str):
-    response = retrieve_download_file(UUID)
-    file_size = int(response.headers.get("content-length", -1))
-    content_type = response.headers.get("content-type")
-    file_format = ""
-
-    print(content_type)
-    if content_type == "application/octet-stream":
-        file_format = "Microsoft spreadsheet"
-    elif content_type == MIMETYPE.JSON:
-        file_format = "JSON"
-    else:
-        file_format = "Unknow type"
-
-    form = RetrieveForm()
-    context = {"UUID": UUID, "file_format": file_format, "file_size": file_size}
+def retrieve_download(filename: str):
+    """Get file from S3, send back to user with presigned link
+    and file metadata, if file is not exist
+    return file not found page
+    :param: filename (str):filename of the file which needs to be retrieved with metadata
+    Returns: redirect to presigned url
+    """
+    response = get_presigned_url(filename)
     if response.status_code == 404:
         return render_template("file-not-found.html")
+
+    file_metadata = get_find_download_file_metadata(filename)
+    form = RetrieveForm()
+    context = {
+        "filename": filename,
+        "file_size": file_metadata.file_size_str,
+        "file_format": file_metadata.file_format,
+        "date": file_metadata.last_modified_date,
+    }
     if form.validate_on_submit():
         if response.status_code == 200:
+            presigned_url = response.json()
             try:
+                user_id = (g.account_id,)
                 current_app.logger.info(
-                    "Request for download by {{user_id=}}",
+                    "Request for download by user_id={user_id}",
                     extra={
-                        "user_id": g.account_id,
+                        "user_id": user_id,
                         "email": g.user.email,
                     },
                 )
-                return Response(
-                    response.iter_content(chunk_size=10 * 1024),
-                    headers={
-                        "Content-Disposition": response.headers.get("Content-Disposition"),
-                        "Content-Type": response.headers.get("Content-Type"),
-                    },
-                )
+                return redirect(presigned_url)
+
             except ValueError:
                 return jsonify({"error": "Invalid response from data store"}), 500
-        else:
-            return jsonify({"error": f"Error retrieving file: {response.status_code}"}), response.status_code
     else:
         return render_template("retrieve-download.html", context=context, form=form)
 

app/static/src/css/custom.css

@@ -3,16 +3,6 @@
 }
 
 
-.govuk-button {
-    background-color: #1d70b8;
-}
-
-
-.govuk-button:hover {
-    background-color: #12066d;
-}
-
-
 .govuk-footer__meta {
     display: flex;
     margin-right: -15px;

app/templates/main/request-received.html

@@ -12,7 +12,7 @@ <h2 class="govuk-heading-m govuk-!-margin-top-7">
             What happens next
         </h2>
         <p class="govuk-body">
-            We will email a link to <span class="govuk-!-font-weight-bold">{{ context["user_email"] }}</span>.
+            We will email a link to <span class="govuk-!-font-weight-bold">{{ user_email }}</span>.
         </p>
         <p class="govuk-body">
             This may take up to 5 minutes to be delivered to your inbox.</p>

app/templates/main/retrieve-download.html

@@ -5,34 +5,13 @@
   <div class="govuk-grid-column-two-thirds">
     <h1 class="govuk-heading-xl">Your data is ready to be downloaded</h1>
     <div class="govuk-inset-text">
-      <p>You requested a data download on <span class="govuk-!-font-weight-bold">{date}</span>.
-      <br>File format: <span class="govuk-!-font-weight-bold">{{ context.file_format }}, {{ context.file_size }} KB</span></p>
+      <p>You requested a data download on <span class="govuk-!-font-weight-bold">{{ context.date }}</span>.
+      <br>File format: <span class="govuk-!-font-weight-bold">{{ context.file_format }}, {{ context.file_size }}</span></p>
     </div>
-    <form id="download-form" method="post" action="{{ url_for('.retrieve_download', uuid=context.UUID) }}">
+    <form id="download-form" method="post" action="{{ url_for('.retrieve_download', filename=context.filename) }}">
       {{ form.csrf_token }}
-      <input type="hidden" name="uuid" id="download-uuid" value="{{ context.UUID }}">
-      <!-- {{ form.download }} -->
-      <button type="submit" class="govuk-button govuk-!-margin-top-3" data-module="govuk-button">
-        Download your data
-      </button>
+      {{ form.download }}
     </form>
   </div>
 </div>
 {% endblock content %}
-
-{% block bodyEnd %}
-  <script>
-    document.addEventListener('DOMContentLoaded',function(){console.log('JavaScript is working!');});
-
-    document.addEventListener('DOMContentLoaded', function() {
-      const uniqueId = document.getElementById('download-uuid').getAttribute('data-uuid');
-      document.getElementById('download-uuid').value = uniqueId;
-
-      setTimeout(function() {
-          document.getElementById('download-form').submit();
-        },
-        3000
-      ); // 3000 milliseconds = 3 seconds
-  });
-</script>
-{% endblock bodyEnd %}