Add support for detecting new pip version (20+) supporting @ in requirements

trains_agent/helper/package/base.py

@@ -66,7 +66,19 @@ class PackageManager(object):
         pass
 
     def upgrade_pip(self):
-        return self._install("pip"+self.get_pip_version(), "--upgrade")
+        result = self._install("pip"+self.get_pip_version(), "--upgrade")
+        packages = self.run_with_env(('list',), output=True).splitlines()
+        # p.split is ('pip', 'x.y.z')
+        pip = [p.split() for p in packages if len(p.split()) == 2 and p.split()[0] == 'pip']
+        if pip:
+            # noinspection PyBroadException
+            try:
+                from .requirements import MarkerRequirement
+                pip = pip[0][1].split('.')
+                MarkerRequirement.pip_new_version = bool(int(pip[0]) >= 20)
+            except Exception:
+                pass
+        return result
 
     def get_python_command(self, extra=()):
         # type: (...) -> Executable

trains_agent/helper/package/requirements.py

@@ -35,6 +35,10 @@ class FatalSpecsResolutionError(Exception):
 @six.python_2_unicode_compatible
 class MarkerRequirement(object):
 
+    # if True pip version above 20.x and with support for "package @ scheme://link"
+    # default is True
+    pip_new_version = True
+
     def __init__(self, req):  # type: (Requirement) -> None
         self.req = req
 
@@ -65,6 +69,10 @@ class MarkerRequirement(object):
                     '@{}'.format(self.revision) if self.revision else '',
                     '#subdirectory={}'.format(self.subdirectory) if self.subdirectory else ''
                 ]
+        elif self.pip_new_version and self.uri and self.name and self.line:
+            # package @ https://example.com/somewheel.whl
+            # leave the line as is, let pip handle it
+            return self.line
         else:
             parts = [self.uri]
 
@@ -492,6 +500,9 @@ class RequirementsManager(object):
                 raise
 
     def replace_back(self, requirements):
+        if self.translator:
+            requirements = self.translator.replace_back(requirements)
+
         for h in self.handlers:
             try:
                 requirements = h.replace_back(requirements)