Adjusted version parsing logic to effectively set "development" and s…

…imilar labels as an alias to grabbing the most recent pipeline version

This allows us to be able to request "pipeline@1.0.0.dev1" via "pipeline@development".
Additionally if "pipeline@development" does exist in the search path, it is considered as the most recent version.

jetstream/pipelines.py

@@ -48,6 +48,7 @@ class Pipeline:
       these: can be anything
 
     """
+
     def __init__(self, path=None, validate=True):
         if path is None:
             path = os.getcwd()
@@ -141,7 +142,6 @@ def set_environment_variables(self):
                 os.environ[k] = v
 
 
-
 def find_pipelines(*dirs):
     """Generator yields all pipelines in given directories. Any pipeline found will also
     be searched for nested pipelines. """
@@ -170,21 +170,39 @@ def find_pipelines(*dirs):
                 yield from find_pipelines(path)
 
 
+def parse_pipeline_version(version):
+    """
+    Pipeline versions generally should not use epochs however if an epoch is used, then it
+    should be less than 999 as in other words that means we had 999 versioning format changes
+    https://peps.python.org/pep-0440/#version-epochs
+    For example an epoch is used to fix this sort order:
+    1.0               2013.10
+    1.1               2014.04
+    2.0       --->    1!1.0
+    2013.10           1!1.1
+    2014.04           1!2.0
+    """
+    if version in ["dev", "develop", "development", "latest"]:
+        return parse_version("999!9")
+    else:
+        return parse_version(version)
+
+
 def get_pipeline(name, version=None, searchpath=None):
     """Get a pipeline by name and version(optional)"""
     if searchpath is None:
         searchpath = jetstream.settings['pipelines']['searchpath'].get()
         searchpath = searchpath.split(':')
 
-    if version is None:
+    if version in [None, "dev", "develop", "development", "latest"]:
         # Find all but then sort by version and return the latest
         matches = []
         for p in find_pipelines(*searchpath):
             if p.name == name:
                 matches.append(p)
 
         if matches:
-            s = sorted(matches, key=lambda p: parse_version(p.version))
+            s = sorted(matches, key=lambda p: parse_pipeline_version(p.version))
             return s[-1]
     else:
         # Find a match with name and version
@@ -193,7 +211,6 @@ def get_pipeline(name, version=None, searchpath=None):
             if p.name == name and parse_version(str(p.version)) == parse_version(str(version)):
                 return p
 
-
     if version is None:
         msg = f'Pipeline "{name}" not found!'
     else:
@@ -214,4 +231,3 @@ def is_pipeline(path):
 def list_pipelines(*dirs):
     """Returns all pipelines found as a list"""
     return list(find_pipelines(*dirs))
-