Browse the data

1from fastapi import FastAPI, HTTPException, Header
2from pydantic import BaseModel
3from typing import Optional
4import secrets
5import time
6 
7app = FastAPI()
8 
9users = {}
10tokens = {}
11loan_requests = {}
12fundings = {}
13repayments = {}
14loans = {}
15user_id_counter = 1
16loan_request_id_counter = 1
17funding_id_counter = 1
18repayment_id_counter = 1
19loan_id_counter = 1
20 
21class SignupRequest(BaseModel):
22    name: str
23    email: str
24    password: str
25 
26class LoginRequest(BaseModel):
27    email: str
28    password: str
29 
30class LoanRequestCreate(BaseModel):
31    amount: float
32    interest_rate: float
33    term_days: int
34 
35class FundingCreate(BaseModel):
36    loan_request_id: int
37    amount: float
38 
39class RepaymentCreate(BaseModel):
40    loan_id: int
41    amount: float
42 
43def get_current_user(authorization: Optional[str] = Header(None)):
44    if not authorization:
45        raise HTTPException(status_code=401, detail="Missing auth header")
46    token = authorization.replace("Bearer ", "")
47    if token not in tokens:
48        raise HTTPException(status_code=401, detail="Invalid token")
49    return tokens[token]
50 
51@app.post("/signup")
52def signup(req: SignupRequest):
53    global user_id_counter
54    for u in users.values():
55        if u["email"] == req.email:
56            raise HTTPException(status_code=400, detail="Email already exists")
57    user_id = user_id_counter
58    user_id_counter += 1
59    users[user_id] = {"id": user_id, "name": req.name, "email": req.email, "password": req.password, "balance": 0.0}
60    return {"user_id": user_id, "name": req.name, "email": req.email}
61 
62@app.post("/login")
63def login(req: LoginRequest):
64    for u in users.values():
65        if u["email"] == req.email and u["password"] == req.password:
66            token = secrets.token_hex(16)
67            tokens[token] = u["id"]
68            return {"token": token}
69    raise HTTPException(status_code=401, detail="Invalid credentials")
70 
71@app.post("/loan_requests")
72def create_loan_request(req: LoanRequestCreate, authorization: Optional[str] = Header(None)):
73    global loan_request_id_counter
74    user_id = get_current_user(authorization)
75    lr_id = loan_request_id_counter
76    loan_request_id_counter += 1
77    loan_requests[lr_id] = {
78        "id": lr_id,
79        "borrower_id": user_id,
80        "amount": req.amount,
81        "interest_rate": req.interest_rate,
82        "term_days": req.term_days,
83        "status": "open",
84        "funded_amount": 0.0,
85        "created_at": time.time()
86    }
87    return loan_requests[lr_id]
88 
89@app.get("/loan_requests/{lr_id}")
90def get_loan_request(lr_id: int, authorization: Optional[str] = Header(None)):
91    user_id = get_current_user(authorization)
92    if lr_id not in loan_requests:
93        raise HTTPException(status_code=404, detail="Loan request not found")
94    return loan_requests[lr_id]
95 
96@app.post("/fundings")
97def create_funding(req: FundingCreate, authorization: Optional[str] = Header(None)):
98    global funding_id_counter
99    lender_id = get_current_user(authorization)
100    if req.loan_request_id not in loan_requests:
101        raise HTTPException(status_code=404, detail="Loan request not found")
102    lr = loan_requests[req.loan_request_id]
103    if lr["status"] != "open":
104        raise HTTPException(status_code=400, detail="Loan request is not open")
105    if lr["borrower_id"] == lender_id:
106        raise HTTPException(status_code=400, detail="Cannot fund your own loan request")
107    remaining = lr["amount"] - lr["funded_amount"]
108    if req.amount > remaining:
109        raise HTTPException(status_code=400, detail="Funding amount exceeds remaining")
110    fid = funding_id_counter
111    funding_id_counter += 1
112    fundings[fid] = {
113        "id": fid,
114        "loan_request_id": req.loan_request_id,
115        "lender_id": lender_id,
116        "amount": req.amount,
117        "created_at": time.time()
118    }
119    lr["funded_amount"] += req.amount
120    if lr["funded_amount"] >= lr["amount"]:
121        lr["status"] = "funded"
122        global loan_id_counter
123        loan_id = loan_id_counter
124        loan_id_counter += 1
125        loans[loan_id] = {
126            "id": loan_id,
127            "loan_request_id": req.loan_request_id,
128            "borrower_id": lr["borrower_id"],
129            "amount": lr["amount"],
130            "interest_rate": lr["interest_rate"],
131            "term_days": lr["term_days"],
132            "status": "active",
133            "outstanding": lr["amount"] * (1 + lr["interest_rate"] / 100),
134            "created_at": time.time()
135        }
136    return fundings[fid]
137 
138@app.get("/fundings/{fid}")
139def get_funding(fid: int, authorization: Optional[str] = Header(None)):
140    user_id = get_current_user(authorization)
141    if fid not in fundings:
142        raise HTTPException(status_code=404, detail="Funding not found")
143    return fundings[fid]
144 
145@app.post("/repayments")
146def create_repayment(req: RepaymentCreate, authorization: Optional[str] = Header(None)):
147    global repayment_id_counter
148    borrower_id = get_current_user(authorization)
149    if req.loan_id not in loans:
150        raise HTTPException(status_code=404, detail="Loan not found")
151    loan = loans[req.loan_id]
152    if loan["borrower_id"] != borrower_id:
153        raise HTTPException(status_code=403, detail="You are not the borrower of this loan")
154    if loan["status"] != "active":
155        raise HTTPException(status_code=400, detail="Loan is not active")
156    if req.amount > loan["outstanding"]:
157        raise HTTPException(status_code=400, detail="Repayment amount exceeds outstanding")
158    rid = repayment_id_counter
159    repayment_id_counter += 1
160    repayments[rid] = {
161        "id": rid,
162        "loan_id": req.loan_id,
163        "borrower_id": borrower_id,
164        "amount": req.amount,
165        "created_at": time.time()
166    }
167    loan["outstanding"] -= req.amount
168    if loan["outstanding"] <= 0:
169        loan["status"] = "paid"
170    return repayments[rid]
171 
172@app.get("/repayments/{rid}")
173def get_repayment(rid: int, authorization: Optional[str] = Header(None)):
174    user_id = get_current_user(authorization)
175    if rid not in repayments:
176        raise HTTPException(status_code=404, detail="Repayment not found")
177    return repayments[rid]
178 
179@app.get("/loans/{loan_id}")
180def get_loan(loan_id: int, authorization: Optional[str] = Header(None)):
181    user_id = get_current_user(authorization)
182    if loan_id not in loans:
183        raise HTTPException(status_code=404, detail="Loan not found")
184    return loans[loan_id]

1fastapi
2uvicorn