get_astronomy_picture_of_day

Instructions

Implementation Reference

• src/nasa_mcp/server.py:86-149 (handler)

  The handler function that implements the 'get_astronomy_picture_of_day' tool. It fetches APOD data from the NASA API, handles single or multiple images, formats the response with title, explanation, URL, etc., and includes error handling.

  @mcp.tool()
  async def get_astronomy_picture_of_day(date: str = None, count: int = None, thumbs: bool = False) -> str:
      """Get NASA's astronomy picture of the day.
      
      Args:
          date: Date of the image in YYYY-MM-DD format. If not specified, the current date is used.
          count: If specified, returns 'count' random images. Cannot be used with 'date'.
          thumbs: If True, returns the thumbnail URL for videos. If APOD is not a video, this parameter is ignored.
      """
      params = {}
      
      if date:
          params["date"] = date
      if count:
          params["count"] = count
      if thumbs:
          params["thumbs"] = "true"
      
      url = f"{NASA_API_BASE}/planetary/apod"
      data = await make_nasa_request(url, params)
      
      if not data:
          return "Could not retrieve astronomy picture of the day data due to a connection error."
      
      # Check for error response (must be a dictionary)
      if isinstance(data, dict) and "error" in data:
          return f"API Error: {data.get('error')} - Details: {data.get('details', 'N/A')}"
      if isinstance(data, dict) and data.get("binary_content"):
           # APOD URL itself might point to an image, but the API response should be JSON
          return f"Received unexpected binary content from APOD API. URL: {data.get('url')}"
  
      try:
          # If count is specified, data will be a list
          if isinstance(data, list):
              result = []
              for item in data:
                  result.append(f"Date: {item.get('date', 'Unknown')}")
                  result.append(f"Title: {item.get('title', 'No title')}")
                  result.append(f"Explanation: {item.get('explanation', 'No explanation')}")
                  result.append(f"URL: {item.get('url', 'Not available')}")
                  if 'copyright' in item:
                      result.append(f"Copyright: {item.get('copyright', 'Unknown')}")
                  if thumbs and 'thumbnail_url' in item:
                      result.append(f"Thumbnail URL: {item.get('thumbnail_url', 'Not available')}")
                  result.append("-" * 40)
              
              return "n".join(result)
          else:
              # If it's a single image
              result = f"""
  Date: {data.get('date', 'Unknown')}
  Title: {data.get('title', 'No title')}
  Explanation: {data.get('explanation', 'No explanation')}
  URL: {data.get('url', 'Not available')}
  """
              if 'copyright' in data:
                  result += f"Copyright: {data.get('copyright', 'Unknown')}n"
              if thumbs and 'thumbnail_url' in data:
                  result += f"Thumbnail URL: {data.get('thumbnail_url', 'Not available')}n"
              
              return result
      except Exception as e:
          logger.error(f"Error processing APOD data: {str(e)}")
          return f"Error processing astronomy picture data: {str(e)}"

• src/nasa_mcp/server.py:28-82 (helper)

  Shared helper function used by the tool (and others) to perform HTTP requests to NASA APIs, automatically adding the API key, handling JSON/binary responses, timeouts, redirects, and various errors.

  async def make_nasa_request(url: str, params: dict = None) -> Union[dict[str, Any], List[Any], None]:
      """Make a request to the NASA API with proper error handling.
      Handles both JSON and binary (image) responses.
      """
      
      logger.info(f"Making request to: {url} with params: {params}")
      
      if params is None:
          params = {}
      
      # Ensure API key is included in parameters
      if "api_key" not in params:
          params["api_key"] = API_KEY
      
      async with httpx.AsyncClient() as client:
          try:
              response = await client.get(url, params=params, timeout=30.0, follow_redirects=True)
              response.raise_for_status() # Raise an exception for bad status codes (4xx or 5xx)
  
              content_type = response.headers.get("Content-Type", "").lower()
              
              if "application/json" in content_type:
                  try:
                      return response.json()
                  except json.JSONDecodeError as json_err:
                      logger.error(f"JSON decode error for URL {response.url}: {json_err}")
                      logger.error(f"Response text: {response.text[:500]}") # Log beginning of text
                      return {"error": "Failed to decode JSON response", "details": str(json_err)}
              elif content_type.startswith("image/"):
                  logger.info(f"Received binary image content ({content_type}) from {response.url}")
                  # Return a dictionary indicating binary content was received
                  return {
                      "binary_content": True, 
                      "content_type": content_type,
                      "url": str(response.url) # Return the final URL after redirects
                  }
              else:
                  # Handle other unexpected content types
                  logger.warning(f"Unexpected content type '{content_type}' received from {response.url}")
                  return {"error": f"Unexpected content type: {content_type}", "content": response.text[:500]}
  
          except httpx.HTTPStatusError as http_err:
              logger.error(f"HTTP error occurred: {http_err} - {http_err.response.status_code} for URL {http_err.request.url}")
              try:
                  # Try to get more details from response body if possible
                  error_details = http_err.response.json()
              except Exception:
                  error_details = http_err.response.text[:500]
              return {"error": f"HTTP error: {http_err.response.status_code}", "details": error_details}
          except httpx.RequestError as req_err:
              logger.error(f"Request error occurred: {req_err} for URL {req_err.request.url}")
              return {"error": "Request failed", "details": str(req_err)}
          except Exception as e:
              logger.error(f"An unexpected error occurred: {str(e)}")
              return {"error": "An unexpected error occurred", "details": str(e)}