ranaroussi/yfinance v1.0.0 Update #

On December 23rd (KST), ranaroussi/yfinance was updated to v1.0.0.

The update introduces Calendars, a new feature for querying market-wide events, and Lookup, which expands ticker search capabilities. Additionally, Sector, Industry, and Market features have been added, enabling analysis by sector, industry, and market.

v1.0.0 Major Changes #

Feature Comparison: go-yfinance vs. ranaroussi/yfinance v1.0.0 #

• All existing features are identical; however, four features from v1.0.0 were missing in go-yfinance.

Analysis of Unimplemented Modules #

Lookup #

API Analysis

Usage (Python)

yf.Lookup(query="AAPL")  # Search ticker by ISIN, CUSIP, etc.

Request Parameters

• query: Search term (Required)
• type: all, equity, mutualfund, etf, index, future, currency, cryptocurrency
• count: Number of results (Default 25)
• start: Pagination
• formatted: false
• fetchPricingData: true
• lang: en-US
• region: US

Response Structure

{
  "finance": {
    "result": [{
      "documents": [
        {"symbol": "AAPL", "name": "Apple Inc.", "exchange": "NMS", ...}
      ]
    }]
  }
}

Implementation Plan

• Model Definition: pkg/models/lookup.go
• Implementation: pkg/lookup/lookup.go
• Testing: pkg/lookup/lookup_test.go
• Estimated Workload: ~300 lines

Calendars #

API Analysis

• go-yfinance’s Calendar() only supports calendars for individual Tickers.
• Python’s Calendars supports querying market-wide calendar events.

Usage (Python)

calendars = yf.Calendars(start="2025-01-01", end="2025-01-07")
calendars.get_earnings_calendar()        # Earnings schedule
calendars.get_ipo_info_calendar()        # IPO schedule
calendars.get_economic_events_calendar() # Economic events
calendars.get_splits_calendar()          # Stock splits schedule

Request Structure (POST Body)

{
  "sortType": "DESC",
  "entityIdType": "sp_earnings|ipo_info|economic_event|splits",
  "sortField": "intradaymarketcap|startdatetime",
  "includeFields": ["ticker", "companyshortname", ...],
  "size": 100,
  "offset": 0,
  "query": {
    "operator": "AND",
    "operands": [
      {"operator": "eq", "operands": ["region", "us"]},
      {"operator": "gte", "operands": ["startdatetime", "2025-01-01"]}
    ]
  }
}

Supported Calendar Types

Implementation Plan

• Model Definition: pkg/models/calendar_market.go
• Query Builder: pkg/calendars/query.go
• Implementation: pkg/calendars/calendars.go
• Testing: pkg/calendars/calendars_test.go
• Estimated Workload: ~700 lines

Domain (Sector/Industry/Market) #

Usage (Python)

yf.Sector("technology")   # Sector info
yf.Industry("software")   # Industry info
yf.Market("us_market")    # Market info

Sector

Provided Data:

• name, symbol, overview (market cap, company count, industry count, etc.)
• top_companies
• top_etfs, top_mutual_funds
• industries (list of included industries)
• research_reports

Industry

Provided Data:

• name, symbol, overview
• sector_key, sector_name (Parent Sector)
• top_companies, top_performing_companies, top_growth_companies
• research_reports

Market

Provided Data:

• status (market state, open/close times, timezone)
• summary (price and change rate by major index)

Implementation Plan

• Models: pkg/models/domain.go
• Common Interface: pkg/domain/domain.go
• Sector: pkg/domain/sector.go
• Industry: pkg/domain/industry.go
• Market: pkg/domain/market.go
• Testing: pkg/domain/*_test.go
• Estimated Workload: ~920 lines

Config #

go-yfinance already implements a richer Config than Python v1.0.0.

Due to language characteristics, Python uses a nested style (config.network.proxy), while Go uses a method chain style (SetProxy()) in its API. However, since Config is set once at application startup and only read thereafter, I determined that there is no practical performance difference, so no changes are necessary.

Performance Comparison

Issues Resolved #

Calendars Earnings API 500 Error

• Cause: Query structure issue - date queries were wrapped in a nested AND.
• Resolution: Added buildDateQueries() to pass GTE/LTE as individual operands.

// Before (Error)
Operands: []interface{}{
    query{Operator: "EQ", ...},
    query{Operator: "AND", Operands: [GTE, LTE]},  // Nested AND
}

// After (Success)
Operands: []interface{}{
    query{Operator: "EQ", ...},
    gteQuery,  // Included directly
    lteQuery,  // Included directly
}

SplitEvent Type Conflict

• Cause: SplitEvent was already defined in pkg/models/response.go.
• Resolution: Renamed to CalendarSplitEvent.

Post Method Signature Mismatch

• Cause: client.Post accepted map[string]string, but Calendars required map[string]interface{}.
• Resolution: Used client.PostJSON + json.Marshal for body serialization.

Result #

go-yfinance v1.0.0 Release Note