Generating the whole errors file from script

psycopg/pqpath.c

@@ -123,6 +123,10 @@ exception_from_sqlstate(const char *sqlstate)
         PyErr_Clear();
     }
 
+    /*
+     * IMPORTANT: if you change anything in this function you should change
+     * make_errors.py accordingly.
+     */
     switch (sqlstate[0]) {
     case '0':
         switch (sqlstate[1]) {

scripts/make_errors.py

@@ -0,0 +1,210 @@
+#!/usr/bin/env python
+"""Generate the errors module from PostgreSQL source code.
+
+The script can be run at a new PostgreSQL release to refresh the module.
+"""
+
+# Copyright (C) 2018 Daniele Varrazzo  <daniele.varrazzo@gmail.com>
+#
+# psycopg2 is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+# License for more details.
+from __future__ import print_function
+
+import re
+import sys
+import urllib2
+from collections import defaultdict
+
+
+def main():
+    if len(sys.argv) != 2:
+        print("usage: %s /path/to/errors.py" % sys.argv[0], file=sys.stderr)
+        return 2
+
+    filename = sys.argv[1]
+
+    file_start = read_base_file(filename)
+    # If you add a version to the list fix the docs (in errors.rst)
+    classes, errors = fetch_errors(
+        ['9.1', '9.2', '9.3', '9.4', '9.5', '9.6', '10'])
+
+    f = open(filename, "w")
+    for line in file_start:
+        print(line, file=f)
+    for line in generate_module_data(classes, errors):
+        print(line, file=f)
+
+
+def read_base_file(filename):
+    rv = []
+    for line in open(filename):
+        rv.append(line.rstrip("\n"))
+        if line.startswith("# autogenerated"):
+            return rv
+
+    raise ValueError("can't find the separator. Is this the right file?")
+
+
+def parse_errors_txt(url):
+    classes = {}
+    errors = defaultdict(dict)
+
+    page = urllib2.urlopen(url)
+    for line in page:
+        # Strip comments and skip blanks
+        line = line.split('#')[0].strip()
+        if not line:
+            continue
+
+        # Parse a section
+        m = re.match(r"Section: (Class (..) - .+)", line)
+        if m:
+            label, class_ = m.groups()
+            classes[class_] = label
+            continue
+
+        # Parse an error
+        m = re.match(r"(.....)\s+(?:E|W|S)\s+ERRCODE_(\S+)(?:\s+(\S+))?$", line)
+        if m:
+            errcode, macro, spec = m.groups()
+            # skip errcodes without specs as they are not publically visible
+            if not spec:
+                continue
+            errlabel = spec.upper()
+            errors[class_][errcode] = errlabel
+            continue
+
+        # We don't expect anything else
+        raise ValueError("unexpected line:\n%s" % line)
+
+    return classes, errors
+
+
+errors_txt_url = \
+    "http://git.postgresql.org/gitweb/?p=postgresql.git;a=blob_plain;" \
+    "f=src/backend/utils/errcodes.txt;hb=%s"
+
+
+def fetch_errors(versions):
+    classes = {}
+    errors = defaultdict(dict)
+
+    for version in versions:
+        print(version, file=sys.stderr)
+        tver = tuple(map(int, version.split()[0].split('.')))
+        tag = '%s%s_STABLE' % (
+            (tver[0] >= 10 and 'REL_' or 'REL'),
+            version.replace('.', '_'))
+        c1, e1 = parse_errors_txt(errors_txt_url % tag)
+        classes.update(c1)
+
+        for c, cerrs in e1.items():
+            errors[c].update(cerrs)
+
+    return classes, errors
+
+
+def generate_module_data(classes, errors):
+    tmpl = """
+
+class %(cls)s(%(base)s):
+    pass
+
+_by_sqlstate[%(errcode)r] = %(cls)s\
+"""
+    for clscode, clslabel in sorted(classes.items()):
+        if clscode in ('00', '01'):
+            # success and warning - never raised
+            continue
+
+        yield "\n\n# %s" % clslabel
+
+        for errcode, errlabel in sorted(errors[clscode].items()):
+            clsname = errlabel.title().replace('_', '')
+            yield tmpl % {
+                'cls': clsname,
+                'base': get_base_class_name(errcode),
+                'errcode': errcode
+            }
+
+
+def get_base_class_name(errcode):
+    """
+    This is a python porting of exception_from_sqlstate code in pqpath.c
+    """
+    if errcode[0] == '0':
+        if errcode[1] == 'A':   # Class 0A - Feature Not Supported
+            return 'NotSupportedError'
+    elif errcode[0] == '2':
+        if errcode[1] in '01':
+            # Class 20 - Case Not Found
+            # Class 21 - Cardinality Violation
+            return 'ProgrammingError'
+        elif errcode[1] == '2':   # Class 22 - Data Exception
+            return 'DataError'
+        elif errcode[1] == '3':   # Class 23 - Integrity Constraint Violation
+            return 'IntegrityError'
+        elif errcode[1] in '45':
+            # Class 24 - Invalid Cursor State
+            # Class 25 - Invalid Transaction State
+            return 'InternalError'
+        elif errcode[1] in '678':
+            # Class 26 - Invalid SQL Statement Name
+            # Class 27 - Triggered Data Change Violation
+            # Class 28 - Invalid Authorization Specification
+            return 'OperationalError'
+        elif errcode[1] in 'BDF':
+            # Class 2B - Dependent Privilege Descriptors Still Exist
+            # Class 2D - Invalid Transaction Termination
+            # Class 2F - SQL Routine Exception
+            return 'InternalError'
+    elif errcode[0] == '3':
+        if errcode[1] == '4':   # Class 34 - Invalid Cursor Name
+            return 'OperationalError'
+        if errcode[1] in '89B':
+            # Class 38 - External Routine Exception
+            # Class 39 - External Routine Invocation Exception
+            # Class 3B - Savepoint Exception
+            return 'InternalError'
+        if errcode[1] in 'DF':
+            # Class 3D - Invalid Catalog Name
+            # Class 3F - Invalid Schema Name
+            return 'ProgrammingError'
+    elif errcode[0] == '4':
+        if errcode[1] == '0':   # Class 40 - Transaction Rollback
+            return 'TransactionRollbackError'
+        if errcode[1] in '24':
+            # Class 42 - Syntax Error or Access Rule Violation
+            # Class 44 - WITH CHECK OPTION Violation
+            return 'ProgrammingError'
+    elif errcode[0] == '5':
+        if errcode == "57014":
+            return 'QueryCanceledError'
+        # Class 53 - Insufficient Resources
+        # Class 54 - Program Limit Exceeded
+        # Class 55 - Object Not In Prerequisite State
+        # Class 57 - Operator Intervention
+        # Class 58 - System Error (errors external to PostgreSQL itself)
+        else:
+            return 'OperationalError'
+    elif errcode[0] == 'F':     # Class F0 - Configuration File Error
+        return 'InternalError'
+    elif errcode[0] == 'H':     # Class HV - Foreign Data Wrapper Error (SQL/MED)
+        return 'OperationalError'
+    elif errcode[0] == 'P':     # Class P0 - PL/pgSQL Error
+        return 'InternalError'
+    elif errcode[0] == 'X':     # Class XX - Internal Error
+        return 'InternalError'
+
+    return 'DatabaseError'
+
+
+if __name__ == '__main__':
+    sys.exit(main())