Access database and other files through features, for simpler configuration

src/sage/combinat/designs/latin_squares.py

@@ -75,7 +75,7 @@
       0|                                                           +               +
      20|
      40|
-     60|   +
+     60|
      80|
     100|
     120|
@@ -126,7 +126,6 @@
 from sage.rings.integer import Integer
 from sage.categories.sets_cat import EmptySetError
 from sage.misc.unknown import Unknown
-from sage.env import COMBINATORIAL_DESIGN_DATA_DIR
 
 
 def are_mutually_orthogonal_latin_squares(l, verbose=False):
@@ -500,13 +499,13 @@ def MOLS_table(start,stop=None,compare=False,width=None):
           0|                                                           +               +
          20|
          40|
-         60|   +
+         60|
          80|
         sage: MOLS_table(50, 100, compare=True)
                0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17  18  19
             ________________________________________________________________________________
          40|
-         60|   +
+         60|
          80|
     """
     from .orthogonal_arrays import largest_available_k
@@ -520,11 +519,6 @@ def MOLS_table(start,stop=None,compare=False,width=None):
     if stop <= start:
         return
 
-    if compare:
-        handbook_file = open("{}/MOLS_table.txt".format(COMBINATORIAL_DESIGN_DATA_DIR), 'r')
-        hb = [int(_) for _ in handbook_file.readlines()[9].split(',')]
-        handbook_file.close()
-
     # choose an appropriate width (needs to be >= 3 because "+oo" should fit)
     if width is None:
         width = max(3, Integer(stop-1).ndigits(10))
@@ -537,9 +531,11 @@ def MOLS_table(start,stop=None,compare=False,width=None):
             print("\n{:>{width}}|".format(i, width=width), end="")
         k = largest_available_k(i)-2
         if compare:
-            if i < 2 or hb[i] == k:
+            from . import MOLS_handbook_data
+            lower_bound = MOLS_handbook_data.lower_bound(i)
+            if i < 2 or lower_bound == k:
                 c = ""
-            elif hb[i] < k:
+            elif lower_bound < k:
                 c = "+"
             else:
                 c = "-"

src/sage/databases/jones.py

@@ -79,8 +79,6 @@
 
 from sage.features.databases import DatabaseJones
 
-JONESDATA = os.path.join(SAGE_SHARE, 'jones')  # should match the filename set in DatabaseJones
-
 
 def sortkey(K):
     """
@@ -160,8 +158,10 @@ def _init(self, path):
                 for Y in os.listdir(Z):
                     if Y[-3:] == ".gp":
                         self._load(Z, Y)
-        os.makedirs(JONESDATA, exist_ok=True)
-        save(self.root, JONESDATA + "/jones.sobj")
+
+        data_dir = os.path.dirname(DatabaseJones().absolute_filename())
+        os.makedirs(data_dir, exist_ok=True)
+        save(self.root, os.path.join(data_dir, "jones.sobj"))
 
     def unramified_outside(self, S, d=None, var='a'):
         """

src/sage/databases/sql_db.py

@@ -250,7 +250,6 @@ def construct_skeleton(database):
     skeleton = {}
     cur = database.__connection__.cursor()
     exe = cur.execute("SELECT name FROM sqlite_master WHERE TYPE='table'")
-    from sage.env import GRAPHS_DATA_DIR
     for table in exe.fetchall():
         skeleton[table[0]] = {}
         exe1 = cur.execute("PRAGMA table_info(%s)" % table[0])
@@ -264,8 +263,7 @@ def construct_skeleton(database):
         exe2 = cur.execute("PRAGMA index_list(%s)" % table[0])
         for col in exe2.fetchall():
             if col[1].find('sqlite') == -1:
-                if database.__dblocation__ == \
-                        os.path.join(GRAPHS_DATA_DIR,'graphs.db'):
+                if os.path.basename(database.__dblocation__) == 'graphs.db':
                     name = col[1]
                 else:
                     name = col[1][len(table[0])+3:]

src/sage/env.py

@@ -195,18 +195,26 @@ def var(key: str, *fallbacks: Optional[str], force: bool = False) -> Optional[st
 SAGE_ARCHFLAGS = var("SAGE_ARCHFLAGS", "unset")
 SAGE_PKG_CONFIG_PATH = var("SAGE_PKG_CONFIG_PATH")
 
+# colon-separated search path for databases.
+SAGE_DATA_PATH = var("SAGE_DATA_PATH",
+                     os.pathsep.join(filter(None, [
+                         join(DOT_SAGE, "db"),
+                         join(SAGE_SHARE, "sagemath"),
+                         SAGE_SHARE,
+                         ])))
+
+# database directories, the default is to search in SAGE_DATA_PATH
+CREMONA_LARGE_DATA_DIR = var("CREMONA_LARGE_DATA_DIR")
+CREMONA_MINI_DATA_DIR = var("CREMONA_MINI_DATA_DIR")
+ELLCURVE_DATA_DIR = var("ELLCURVE_DATA_DIR")
+GRAPHS_DATA_DIR = var("GRAPHS_DATA_DIR")
+POLYTOPE_DATA_DIR = var("POLYTOPE_DATA_DIR")
+
 # installation directories for various packages
-GRAPHS_DATA_DIR = var("GRAPHS_DATA_DIR", join(SAGE_SHARE, "graphs"))
-ELLCURVE_DATA_DIR = var("ELLCURVE_DATA_DIR", join(SAGE_SHARE, "ellcurves"))
-POLYTOPE_DATA_DIR = var("POLYTOPE_DATA_DIR", join(SAGE_SHARE, "reflexive_polytopes"))
-
-COMBINATORIAL_DESIGN_DATA_DIR = var("COMBINATORIAL_DESIGN_DATA_DIR", join(SAGE_SHARE, "combinatorial_designs"))
-CREMONA_MINI_DATA_DIR = var("CREMONA_MINI_DATA_DIR", join(SAGE_SHARE, "cremona"))
-CREMONA_LARGE_DATA_DIR = var("CREMONA_LARGE_DATA_DIR", join(SAGE_SHARE, "cremona"))
-JMOL_DIR = var("JMOL_DIR", join(SAGE_SHARE, "jmol"))
+JMOL_DIR = var("JMOL_DIR")
 MATHJAX_DIR = var("MATHJAX_DIR", join(SAGE_SHARE, "mathjax"))
 MTXLIB = var("MTXLIB", join(SAGE_SHARE, "meataxe"))
-THREEJS_DIR = var("THREEJS_DIR", join(SAGE_SHARE, "threejs-sage"))
+THREEJS_DIR = var("THREEJS_DIR")
 PPLPY_DOCS = var("PPLPY_DOCS", join(SAGE_SHARE, "doc", "pplpy"))
 MAXIMA = var("MAXIMA", "maxima")
 MAXIMA_FAS = var("MAXIMA_FAS")
@@ -313,6 +321,7 @@ def sage_include_directories(use_sources=False):
 
     return dirs
 
+
 def get_cblas_pc_module_name() -> str:
     """
     Return the name of the BLAS libraries to be used.
@@ -420,7 +429,7 @@ def cython_aliases(required_modules=None,
             aliases["ECL_INCDIR"] = list(map(lambda s: s[2:], filter(lambda s: s.startswith('-I'), ecl_cflags)))
             aliases["ECL_LIBDIR"] = list(map(lambda s: s[2:], filter(lambda s: s.startswith('-L'), ecl_libs)))
             aliases["ECL_LIBRARIES"] = list(map(lambda s: s[2:], filter(lambda s: s.startswith('-l'), ecl_libs)))
-            aliases["ECL_LIBEXTRA"] = list(filter(lambda s: not s.startswith(('-l','-L')), ecl_libs))
+            aliases["ECL_LIBEXTRA"] = list(filter(lambda s: not s.startswith(('-l', '-L')), ecl_libs))
             continue
         else:
             try:
@@ -439,7 +448,7 @@ def cython_aliases(required_modules=None,
         # include search order matters.
         aliases[var + "INCDIR"] = pc['include_dirs']
         aliases[var + "LIBDIR"] = pc['library_dirs']
-        aliases[var + "LIBEXTRA"] = list(filter(lambda s: not s.startswith(('-l','-L')), libs.split()))
+        aliases[var + "LIBEXTRA"] = list(filter(lambda s: not s.startswith(('-l', '-L')), libs.split()))
         aliases[var + "LIBRARIES"] = pc['libraries']
 
     # uname-specific flags

src/sage/features/__init__.py

@@ -416,6 +416,7 @@ def unhide(self):
         """
         self._hidden = False
 
+
 class FeatureNotPresentError(RuntimeError):
     r"""
     A missing feature error.
@@ -791,26 +792,37 @@ class StaticFile(FileFeature):
     EXAMPLES::
 
         sage: from sage.features import StaticFile
-        sage: StaticFile(name="no_such_file", filename="KaT1aihu", search_path=("/",), spkg="some_spkg", url="http://rand.om").require()  # optional - sage_spkg
+        sage: StaticFile(name="no_such_file", filename="KaT1aihu",              # optional - sage_spkg
+        ....:            search_path="/", spkg="some_spkg",
+        ....:            url="http://rand.om").require()
         Traceback (most recent call last):
         ...
         FeatureNotPresentError: no_such_file is not available.
         'KaT1aihu' not found in any of ['/']...
         To install no_such_file...you can try to run...sage -i some_spkg...
         Further installation instructions might be available at http://rand.om.
     """
-    def __init__(self, name, filename, search_path=None, **kwds):
+    def __init__(self, name, filename, *, search_path=None, **kwds):
         r"""
         TESTS::
 
             sage: from sage.features import StaticFile
-            sage: StaticFile(name="null", filename="null", search_path=("/dev",))
+            sage: StaticFile(name="null", filename="null", search_path="/dev")
             Feature('null')
+            sage: sh = StaticFile(name="shell", filename="sh",
+            ....:                 search_path=("/dev", "/bin", "/usr"))
+            sage: sh
+            Feature('shell')
+            sage: sh.absolute_filename()
+            '/bin/sh'
+
         """
         Feature.__init__(self, name, **kwds)
         self.filename = filename
         if search_path is None:
             self.search_path = [SAGE_SHARE]
+        elif isinstance(search_path, str):
+            self.search_path = [search_path]
         else:
             self.search_path = list(search_path)