Added search feature (#98)

* Added search feature

Author: advaa123

.gitignore

@@ -138,4 +138,9 @@ dmypy.json
 # Pyre type checker
 .pyre/
 
+
+# VScode
+.vscode/
+app/.vscode/
+
 app/routers/stam

app/config.py.example

@@ -1,14 +1,15 @@
 import os
 
 from fastapi_mail import ConnectionConfig
-
 # flake8: noqa
 
 # general
 DOMAIN = 'Our-Domain'
 
 # DATABASE
 DEVELOPMENT_DATABASE_STRING = "sqlite:///./dev.db"
+# Set the following True if working on PSQL environment or set False otherwise
+PSQL_ENVIRONMENT = False
 
 # MEDIA
 MEDIA_DIRECTORY = 'media'

app/database/database.py

@@ -6,12 +6,20 @@
 
 from app import config
 
+
 SQLALCHEMY_DATABASE_URL = os.getenv(
     "DATABASE_CONNECTION_STRING", config.DEVELOPMENT_DATABASE_STRING)
 
-engine = create_engine(
-    SQLALCHEMY_DATABASE_URL, connect_args={"check_same_thread": False}
-)
+
+def create_env_engine(psql_environment, sqlalchemy_database_url):
+    if not psql_environment:
+        return create_engine(
+            sqlalchemy_database_url, connect_args={"check_same_thread": False})
+
+    return create_engine(sqlalchemy_database_url)
+
+
+engine = create_env_engine(config.PSQL_ENVIRONMENT, SQLALCHEMY_DATABASE_URL)
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 
 Base = declarative_base()

app/database/models.py

@@ -1,9 +1,11 @@
 from datetime import datetime
 
-from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String
-from sqlalchemy.orm import relationship
-
+from app.config import PSQL_ENVIRONMENT
 from app.database.database import Base
+from sqlalchemy import (DDL, Boolean, Column, DateTime, ForeignKey, Index,
+                        Integer, String, event)
+from sqlalchemy.dialects.postgresql import TSVECTOR
+from sqlalchemy.orm import relationship
 
 
 class UserEvent(Base):
@@ -54,10 +56,39 @@ class Event(Base):
 
     participants = relationship("UserEvent", back_populates="events")
 
+    # PostgreSQL
+    if PSQL_ENVIRONMENT:
+        events_tsv = Column(TSVECTOR)
+        __table_args__ = (Index(
+            'events_tsv_idx',
+            'events_tsv',
+            postgresql_using='gin'),
+            )
+
     def __repr__(self):
         return f'<Event {self.id}>'
 
 
+class PSQLEnvironmentError(Exception):
+    pass
+
+
+# PostgreSQL
+if PSQL_ENVIRONMENT:
+    trigger_snippet = DDL("""
+    CREATE TRIGGER ix_events_tsv_update BEFORE INSERT OR UPDATE
+    ON events
+    FOR EACH ROW EXECUTE PROCEDURE
+    tsvector_update_trigger(events_tsv,'pg_catalog.english','title','content')
+    """)
+
+    event.listen(
+        Event.__table__,
+        'after_create',
+        trigger_snippet.execute_if(dialect='postgresql')
+        )
+
+
 class Invitation(Base):
     __tablename__ = "invitations"
 

app/internal/search.py

@@ -0,0 +1,42 @@
+from typing import List
+
+from app.database.database import SessionLocal
+from app.database.models import Event
+from sqlalchemy.exc import SQLAlchemyError
+
+
+def get_stripped_keywords(keywords: str) -> str:
+    '''Gets a string of keywords to search for from the user form
+       and returns a stripped ready-to-db-search keywords string'''
+
+    keywords = " ".join(keywords.split())
+    keywords = keywords.replace(" ", ":* & ") + ":*"
+    return keywords
+
+
+def get_results_by_keywords(
+                            session: SessionLocal,
+                            keywords: str,
+                            owner_id: int
+                           ) -> List[Event]:
+    """Returns possible results for a search in the 'events' database table
+
+    Args:
+        keywords (str): search string
+        owner_id (int): current user id
+
+    Returns:
+        list: a list of events from the database matching the inserted keywords
+
+    Uses PostgreSQL's built in 'Full-text search' feature
+    (doesn't work with SQLite)"""
+
+    keywords = get_stripped_keywords(keywords)
+
+    try:
+        return session.query(Event).filter(
+            Event.owner_id == owner_id,
+            Event.events_tsv.match(keywords)).all()
+
+    except (SQLAlchemyError, AttributeError):
+        return []

app/main.py

@@ -1,15 +1,27 @@
 from fastapi import FastAPI, Request
 from fastapi.staticfiles import StaticFiles
 
+from app.config import PSQL_ENVIRONMENT
 from app.database import models
 from app.database.database import engine
 from app.dependencies import (
     MEDIA_PATH, STATIC_PATH, templates)
-from app.routers import agenda, dayview, event, profile, email, invitation
+from app.routers import (agenda, dayview, email, event, invitation, profile,
+                         search)
 
 
-models.Base.metadata.create_all(bind=engine)
+def create_tables(engine, psql_environment):
+    if 'sqlite' in str(engine.url) and psql_environment:
+        raise models.PSQLEnvironmentError(
+            "You're trying to use PSQL features on SQLite env.\n"
+            "Please set app.config.PSQL_ENVIRONMENT to False "
+            "and run the app again."
+        )
+    else:
+        models.Base.metadata.create_all(bind=engine)
 
+
+create_tables(engine, PSQL_ENVIRONMENT)
 app = FastAPI()
 app.mount("/static", StaticFiles(directory=STATIC_PATH), name="static")
 app.mount("/media", StaticFiles(directory=MEDIA_PATH), name="media")
@@ -20,6 +32,7 @@
 app.include_router(dayview.router)
 app.include_router(email.router)
 app.include_router(invitation.router)
+app.include_router(search.router)
 
 
 @app.get("/")

app/routers/search.py

@@ -0,0 +1,48 @@
+from app.database.database import get_db
+from app.dependencies import templates
+from app.internal.search import get_results_by_keywords
+from fastapi import APIRouter, Depends, Form, Request
+from sqlalchemy.orm import Session
+
+
+router = APIRouter()
+
+
+@router.get("/search")
+def search(request: Request):
+    # Made up user details until there's a user login system
+    current_username = "Chuck Norris"
+
+    return templates.TemplateResponse("search.html", {
+        "request": request,
+        "username": current_username
+    })
+
+
+@router.post("/search")
+async def show_results(
+                        request: Request,
+                        keywords: str = Form(None),
+                        db: Session = Depends(get_db)):
+    # Made up user details until there's a user login system
+    current_username = "Chuck Norris"
+    current_user = 1
+
+    message = ""
+
+    if not keywords:
+        message = "Invalid request."
+        results = None
+    else:
+        results = get_results_by_keywords(db, keywords, owner_id=current_user)
+        if not results:
+            message = f"No matching results for '{keywords}'."
+
+    return templates.TemplateResponse("search.html", {
+        "request": request,
+        "username": current_username,
+        "message": message,
+        "results": results,
+        "keywords": keywords
+        }
+    )

app/templates/base.html

@@ -42,6 +42,9 @@
                     <li class="nav-item">
                         <a class="nav-link" href="{{ url_for('view_invitations') }}">Invitations</a>
                     </li>
+                    <li class="nav-item">
+                        <a class="nav-link" href="/search">Search</a> 
+                    </li>
                 </ul>
             </div>
         </div>

app/templates/profile.html

@@ -246,4 +246,4 @@ <h6 class="card-title text-center mb-1">{{ user.full_name }}</h6>
         </div>
     </div>
 
-{% endblock %}
+{% endblock %}

app/templates/search.html

@@ -0,0 +1,69 @@
+{% extends "base.html" %}
+
+
+{% block content %}
+
+<div class="container mt-4">
+    <h1>Hello, {{ username }}</h1>
+    <form name="searchForm" action="/search" onsubmit="return validateForm()" method="POST" required>
+        <div class="form-row align-items-center">
+            <div class="col-sm-2 my-1">
+                <label for="keywords" class="sr-only">Search event by keyword</label>
+                <input type="text" id="keywords" name="keywords" class="form-control" placeholder="Keywords"
+                    value="{{ keywords }}" onfocus="this.value=''" required>
+            </div>
+            <div class="col my-1">
+                <input type="submit" class="btn btn-primary" value="Search">
+            </div>
+    </form>
+</div>
+
+{% if message %}
+<div class="container mt-4">
+    {{ message }}
+</div>
+{% endif %}
+
+<!-- Results -->
+{% if results %}
+<div class="container mt-4">
+    <div class="my-4">
+        Showing results for '{{ keywords }}':
+    </div>
+    <!-- Center -->
+    <div class="col-5">
+        <div class="mb-3">
+            {% for result in results %}
+            <!-- Events card -->
+            <div class="card card-event mb-2 pb-0">
+                <div class="card-header d-flex justify-content-between">
+                    <small>
+                        <i>{{ loop.index }}. {{ result.title }}</i>
+                    </small>
+                </div>
+                <div class="card-body pb-1">
+                    <p class="card-text">
+                        {{ result.content }}
+                    </p>
+                    <hr class="mb-0">
+                    <small class="event-posted-time text-muted">{{ result.date }}</small>
+                </div>
+            </div>
+            <!-- End Events card -->
+            {% endfor %}
+        </div>
+    </div>
+    {% endif %}
+
+    <!-- Form field validation script -->
+    <script>
+        function validateForm() {
+            var x = document.forms["searchForm"]["keywords"].value;
+            if (x == "") {
+                alert("Name must be filled out");
+                return false;
+            }
+        }
+    </script>
+    <!-- End script -->
+    {% endblock %}