Find chia in env if needed

setup.cfg

@@ -52,10 +52,13 @@ console_scripts =
     plotman = plotman.plotman:main
 
 [options.extras_require]
+chia =
+    chia-blockchain
 dev =
     %(test)s
     isort
 test = 
+    %(chia)s
     check-manifest
     pytest
     pytest-mock

src/plotman/manager.py

@@ -5,7 +5,10 @@
 import re
 import readline  # For nice CLI
 import subprocess
+import shutil
 import sys
+import sysconfig
+import textwrap
 import time
 from datetime import datetime
 
@@ -22,6 +25,51 @@
 
 MAX_AGE = 1000_000_000   # Arbitrary large number of seconds
 
+SCRIPTS_PATH = sysconfig.get_path('scripts')
+
+class ChiaExecutable:
+    def __init__(self, command, path_entry=None):
+        self.command = command
+        self.path_entry = path_entry
+
+    def modified_path(self, path=None):
+        if path is None:
+            path = os.environ['PATH']
+        if self.path_entry is None:
+            return path
+        if len(path) > 0:
+            return os.pathsep.join([self.path_entry, path])
+        return self.path_entry
+
+    def modified_environment(self, environment=None):
+        if environment is None:
+            environment = os.environ
+        return {
+            **environment,
+            'PATH': self.modified_path(path=environment['PATH']),
+        }
+
+class ChiaNotFoundError(Exception):
+    pass
+
+def select_chia_executable():
+    from_path = shutil.which('chia')
+    if from_path is not None:
+        return ChiaExecutable(command=from_path, path_entry=None)
+    in_scripts = os.path.join(SCRIPTS_PATH, 'chia')
+    if sys.platform == 'win32':
+        in_scripts += '.exe'
+    if os.path.isfile(in_scripts):
+        return ChiaExecutable(command=in_scripts, path_entry=SCRIPTS_PATH)
+    message = textwrap.dedent(f'''\
+    'chia' executable not found in PATH or scripts directory
+        PATH: {os.environ['PATH']}
+        scripts: {SCRIPTS_PATH}
+    ''')
+    raise ChiaNotFoundError(message)
+
+CHIA_EXECUTABLE = select_chia_executable()
+
 def dstdirs_to_furthest_phase(all_jobs):
     '''Return a map from dst dir to a phase tuple for the most progressed job
        that is emitting to that dst dir.'''
@@ -104,7 +152,7 @@ def maybe_start_new_plot(dir_cfg, sched_cfg, plotting_cfg):
                 dir_cfg.log, datetime.now().strftime('%Y-%m-%d-%H:%M:%S.log')
             )
 
-            plot_args = ['chia', 'plots', 'create',
+            plot_args = [CHIA_EXECUTABLE.command, 'plots', 'create',
                     '-k', str(plotting_cfg.k),
                     '-r', str(plotting_cfg.n_threads),
                     '-u', str(plotting_cfg.n_buckets),
@@ -127,6 +175,7 @@ def maybe_start_new_plot(dir_cfg, sched_cfg, plotting_cfg):
 
             # start_new_sessions to make the job independent of this controlling tty.
             p = subprocess.Popen(plot_args,
+                env=CHIA_EXECUTABLE.modified_environment(),
                 stdout=open(logfile, 'w'),
                 stderr=subprocess.STDOUT,
                 start_new_session=True)