Moves first_page_url and added functionality for generating the urls

nomad/app/v1/models.py

@@ -31,7 +31,7 @@ from nomad.utils import strip
 from nomad.metainfo import Datetime, MEnum
 from nomad.metainfo.search_extension import metrics, search_quantities, search_sub_sections
 
-from .utils import parameter_dependency_from_model
+from .utils import parameter_dependency_from_model, update_url_query_arguments
 
 
 User = datamodel.User.m_def.a_pydantic.model
@@ -581,6 +581,10 @@ class PaginationResponse(Pagination):
         None, description=strip('''
         The url to get the next page.
         '''))
+    first_page_url: Optional[str] = Field(
+        None, description=strip('''
+        The url to get the first page.
+        '''))
 
     @validator('order_by')
     def validate_order_by(cls, order_by):  # pylint: disable=no-self-argument
@@ -602,16 +606,48 @@ class PaginationResponse(Pagination):
         # No validation - behaviour of this field depends on api method
         return next_page_after_value
 
+    def populate_urls(self, request: Request):
+        '''
+        Populates the urls (`page_url`, `next_page_url`, `first_page_url` from the
+        request and `next_page_after_value`.
+        '''
+        original_url = str(request.url)
+        self.page_url = original_url
+        self.first_page_url = update_url_query_arguments(
+            original_url, page=None, page_after_value=None)
+        if self.next_page_after_value:
+            self.next_page_url = update_url_query_arguments(
+                original_url, page=None, page_after_value=self.next_page_after_value)
+
 
 class IndexBasedPaginationResponse(PaginationResponse):
     prev_page_url: Optional[str] = Field(
         None, description=strip('''
         The url to get the previous page.
         '''))
-    first_page_url: Optional[str] = Field(
-        None, description=strip('''
-        The url to get the first page.
-        '''))
+
+    def populate_page_refs(self, request: Request):
+        '''
+        Provided that `page` and `total` are populated, populates all other references:
+        `page_after_value`, `next_page_after_value`, `page_url`, `next_page_url`,
+        `prev_page_url`, and `first_page_url`.
+        '''
+        has_more_pages = self.total > self.page * self.page_size
+        self.page_after_value = str((self.page - 1) * self.page_size - 1) if self.page > 1 else None
+        self.next_page_after_value = str(self.page * self.page_size - 1) if has_more_pages else None
+
+        original_url = str(request.url)
+        self.page_url = original_url
+        self.first_page_url = update_url_query_arguments(
+            original_url, page=None, page_after_value=None)
+
+        if has_more_pages:
+            self.next_page_url = update_url_query_arguments(
+                original_url, page=self.page + 1, page_after_value=None)
+
+        if self.page > 1:
+            self.prev_page_url = update_url_query_arguments(
+                original_url, page=self.page - 1, page_after_value=None)
 
 
 class EntryBasedPagination(Pagination):

nomad/app/v1/routers/datasets.py

@@ -18,7 +18,8 @@
 
 import re
 from typing import cast, Optional, List
-from fastapi import APIRouter, Depends, Query as FastApiQuery, Path, HTTPException, status
+from fastapi import (
+    APIRouter, Request, Depends, Query as FastApiQuery, Path, HTTPException, status)
 from pydantic import BaseModel, Field, validator
 from datetime import datetime
 import enum
@@ -121,6 +122,7 @@ class DatasetCreate(BaseModel):  # type: ignore
     response_model_exclude_unset=True,
     response_model_exclude_none=True)
 async def get_datasets(
+        request: Request,
         dataset_id: str = FastApiQuery(None),
         name: str = FastApiQuery(None),
         user_id: str = FastApiQuery(None),
@@ -143,10 +145,8 @@ async def get_datasets(
     start = (pagination.page - 1) * pagination.page_size
     end = start + pagination.page_size
 
-    pagination_response = IndexBasedPaginationResponse(
-        total=mongodb_query.count(),
-        next_page_after_value=str(end - 1) if pagination.page != 1 and end < mongodb_query.count() else None,
-        **pagination.dict())  # type: ignore
+    pagination_response = IndexBasedPaginationResponse(total=mongodb_query.count(), **pagination.dict())
+    pagination_response.populate_page_refs(request)
 
     return {
         'pagination': pagination_response,

nomad/app/v1/routers/entries.py

@@ -17,7 +17,7 @@
 #
 
 from typing import Dict, Iterator, Any, List, Set, cast
-from fastapi import APIRouter, Depends, Path, status, HTTPException
+from fastapi import APIRouter, Request, Depends, Path, status, HTTPException
 from fastapi.responses import StreamingResponse
 import os.path
 import io
@@ -101,6 +101,7 @@ def perform_search(*args, **kwargs):
     response_model_exclude_unset=True,
     response_model_exclude_none=True)
 async def post_entries_metadata_query(
+        request: Request,
         data: EntriesMetadata,
         user: User = Depends(get_optional_user)):
 
@@ -121,7 +122,7 @@ async def post_entries_metadata_query(
     and aggregated data over all search results.
     '''
 
-    return perform_search(
+    res = perform_search(
         owner=data.owner,
         query=data.query,
         pagination=data.pagination,
@@ -129,6 +130,8 @@ async def post_entries_metadata_query(
         statistics=data.statistics,
         aggregations=data.aggregations,
         user_id=user.user_id if user is not None else None)
+    res.pagination.populate_urls(request)
+    return res
 
 
 @router.get(
@@ -139,6 +142,7 @@ async def post_entries_metadata_query(
     response_model_exclude_unset=True,
     response_model_exclude_none=True)
 async def get_entries_metadata(
+        request: Request,
         with_query: WithQuery = Depends(query_parameters),
         pagination: EntryPagination = Depends(entry_pagination_parameters),
         required: MetadataRequired = Depends(metadata_required_parameters),
@@ -155,10 +159,12 @@ async def get_entries_metadata(
     `gt`, `lt`, `lte`.
     '''
 
-    return perform_search(
+    res = perform_search(
         owner=with_query.owner, query=with_query.query,
         pagination=pagination, required=required,
         user_id=user.user_id if user is not None else None)
+    res.pagination.populate_urls(request)
+    return res
 
 
 def _do_exaustive_search(owner: Owner, query: Query, include: List[str], user: User) -> Iterator[Dict[str, Any]]:
@@ -349,10 +355,13 @@ _entries_raw_query_docstring = strip('''
     responses=create_responses(_bad_owner_response),
     response_model_exclude_unset=True,
     response_model_exclude_none=True)
-async def post_entries_raw_query(data: EntriesRaw, user: User = Depends(get_optional_user)):
+async def post_entries_raw_query(
+        request: Request, data: EntriesRaw, user: User = Depends(get_optional_user)):
 
-    return _answer_entries_raw_request(
+    res = _answer_entries_raw_request(
         owner=data.owner, query=data.query, pagination=data.pagination, user=user)
+    res.pagination.populate_urls(request)
+    return res
 
 
 @router.get(
@@ -365,12 +374,15 @@ async def post_entries_raw_query(data: EntriesRaw, user: User = Depends(get_opti
     response_model_exclude_none=True,
     responses=create_responses(_bad_owner_response))
 async def get_entries_raw(
+        request: Request,
         with_query: WithQuery = Depends(query_parameters),
         pagination: EntryPagination = Depends(entry_pagination_parameters),
         user: User = Depends(get_optional_user)):
 
-    return _answer_entries_raw_request(
+    res = _answer_entries_raw_request(
         owner=with_query.owner, query=with_query.query, pagination=pagination, user=user)
+    res.pagination.populate_urls(request)
+    return res
 
 
 _entries_raw_download_query_docstring = strip('''
@@ -527,11 +539,13 @@ _entries_archive_docstring = strip('''
     response_model_exclude_none=True,
     responses=create_responses(_bad_owner_response, _bad_archive_required_response))
 async def post_entries_archive_query(
-        data: EntriesArchive, user: User = Depends(get_optional_user)):
+        request: Request, data: EntriesArchive, user: User = Depends(get_optional_user)):
 
-    return _answer_entries_archive_request(
+    res = _answer_entries_archive_request(
         owner=data.owner, query=data.query, pagination=data.pagination,
         required=data.required, user=user)
+    res.pagination.populate_urls(request)
+    return res
 
 
 @router.get(
@@ -544,13 +558,16 @@ async def post_entries_archive_query(
     response_model_exclude_none=True,
     responses=create_responses(_bad_owner_response, _bad_archive_required_response))
 async def get_entries_archive_query(
+        request: Request,
         with_query: WithQuery = Depends(query_parameters),
         pagination: EntryPagination = Depends(entry_pagination_parameters),
         user: User = Depends(get_optional_user)):
 
-    return _answer_entries_archive_request(
+    res = _answer_entries_archive_request(
         owner=with_query.owner, query=with_query.query, pagination=pagination,
         required=None, user=user)
+    res.pagination.populate_urls(request)
+    return res
 
 
 def _answer_entries_archive_download_request(

nomad/app/v1/utils.py

@@ -18,9 +18,10 @@
 
 from typing import Dict, Iterator, Any
 from types import FunctionType
+import urllib
 import sys
 import inspect
-from fastapi import Query, HTTPException  # pylint: disable=unused-import
+from fastapi import Request, Query, HTTPException  # pylint: disable=unused-import
 from pydantic import ValidationError, BaseModel  # pylint: disable=unused-import
 import zipstream
 
@@ -117,3 +118,21 @@ def create_responses(*args):
     return {
         status_code: response
         for status_code, response in args}
+
+
+def update_url_query_arguments(original_url: str, **kwargs) -> str:
+    '''
+    Takes an url, and returns a new url, obtained by updating the query arguments in the
+    `original_url` as specified by the kwargs.
+    '''
+    scheme, netloc, path, params, query, fragment = urllib.parse.urlparse(original_url)
+    query_dict = urllib.parse.parse_qs(query)
+    for k, v in kwargs.items():
+        if v is None:
+            # Unset the value
+            if k in query_dict:
+                query_dict.pop(k)
+        else:
+            query_dict[k] = [str(v)]
+    query = urllib.parse.urlencode(query_dict, doseq=True)
+    return urllib.parse.urlunparse((scheme, netloc, path, params, query, fragment))