openflexure-microscope-server/openflexure_microscope/api/v1.py
2018-11-08 16:17:58 +00:00

118 lines
3.3 KiB
Python

#!/usr/bin/env python
"""
TODO: Reimplement capture methods
TODO: Implement API route to cleanly shut down server
TODO: Implement microscope function API routes (autofocus etc)
"""
from pprint import pprint
from importlib import import_module
import time
import datetime
from flask import (
Flask, render_template, Response,
redirect, request, jsonify, send_file)
import numpy as np
from openflexure_microscope.api.utilities import parse_payload, gen
from openflexure_microscope import Microscope
from openflexure_microscope.camera.pi import StreamingCamera
from openflexure_stage import OpenFlexureStage
import logging, sys
logging.basicConfig(stream=sys.stderr, level=logging.DEBUG)
# Create the microscope object globally (common to all spawned server threads)
microscope = Microscope(
StreamingCamera(),
OpenFlexureStage("/dev/ttyUSB0")
)
# Create flask app
app = Flask(__name__)
# Some useful functions
def uri(suffix, base='/api/v1'):
return base + suffix
# Define front-end routes
@app.route('/')
def index():
"""Video streaming home page."""
return render_template(
'index_v1.html'
)
# Define API routes
# Basic routes
@app.route(uri('/stream'))
def stream():
"""Video streaming route. Put this in the src attribute of an img tag."""
global microscope
return Response(
gen(microscope.camera),
mimetype='multipart/x-mixed-replace; boundary=frame')
@app.route(uri('/state'))
def state():
"""Return JSONified microscope state"""
global microscope
return jsonify(microscope.state)
# Positioning routes
@app.route(uri('/position'), methods=['GET', 'POST', 'PUT'])
def position():
"""Set and get the microscope stage position"""
global microscope
if request.method == 'POST' or request.method == 'PUT':
# Get payload
state = parse_payload(request)
logging.debug(state)
# Construct position array
position = [0, 0, 0]
# Handle absolute positioning
if 'absolute' in state and state['absolute'] is True:
# Get coordinates from payload
for axis, key in enumerate(['x', 'y', 'z']):
if key in state:
position[axis] = int(state[key]-microscope.stage.position[axis])
else:
# Get coordinates from payload
for axis, key in enumerate(['x', 'y', 'z']):
if key in state:
position[axis] = int(state[key])
logging.debug(position)
# Safeguard to prevent moving to an absolute position beyond a fixed limit
if not 'force' in state or state['force'] is False: # Allow for override
# TODO: Make travel_limit a property of the stage or microscope
# TODO: Make travel_limit a 3-axis list
travel_limit = 2000
for axis, pos in enumerate(position):
if abs(pos) > travel_limit:
# Respond with 400 Bad Request
response = {'error': 'Cannot move to absolute position beyond the safeguard limit.'}
return jsonify(response), 400
microscope.stage.move_rel(position)
return jsonify(microscope.state['position'])
if __name__ == '__main__':
app.run(host='0.0.0.0', threaded=True, debug=True, use_reloader=False)