Add PR service deamon to bitbake

Added the initial implementation of the server side PR service.

Signed-off-by: Lianhao Lu <lianhao.lu@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

3 files changed, 309 insertions, 0 deletions

diff --git a/lib/prserv/__init__.py b/lib/prserv/__init__.py
new file mode 100644
index 000000000..2837e135d
--- /dev/null
+++ b/lib/prserv/__init__.py
@@ -0,0 +1,11 @@
+__version__ = "1.0.0"
+
+import os, time
+import sys,logging
+
+def init_logger(logfile, loglevel):
+    numeric_level = getattr(logging, loglevel.upper(), None)
+    if not isinstance(numeric_level, int):
+        raise ValueError('Invalid log level: %s' % loglevel)
+    logging.basicConfig(level=numeric_level, filename=logfile)
+
diff --git a/lib/prserv/db.py b/lib/prserv/db.py
new file mode 100644
index 000000000..bbee9316b
--- /dev/null
+++ b/lib/prserv/db.py
@@ -0,0 +1,100 @@
+import logging
+import os.path
+import errno
+import sys
+import warnings
+import sqlite3
+
+try:
+    import sqlite3
+except ImportError:
+    from pysqlite2 import dbapi2 as sqlite3
+
+sqlversion = sqlite3.sqlite_version_info
+if sqlversion[0] < 3 or (sqlversion[0] == 3 and sqlversion[1] < 3):
+    raise Exception("sqlite3 version 3.3.0 or later is required.")
+
+class NotFoundError(StandardError):
+    pass
+
+class PRTable():
+    def __init__(self,cursor,table):
+        self.cursor = cursor
+        self.table = table
+
+        #create the table
+        self._execute("CREATE TABLE IF NOT EXISTS %s \
+                    (version TEXT NOT NULL, \
+                    checksum TEXT NOT NULL, \
+                    value INTEGER, \
+                    PRIMARY KEY (version,checksum));"
+                      % table)
+
+    def _execute(self, *query):
+        """Execute a query, waiting to acquire a lock if necessary"""
+        count = 0
+        while True:
+            try:
+                return self.cursor.execute(*query)
+            except sqlite3.OperationalError as exc:
+                if 'database is locked' in str(exc) and count < 500:
+                    count = count + 1
+                    continue
+                raise
+            except sqlite3.IntegrityError as exc:
+                print "Integrity error %s" % str(exc)
+                break
+
+    def getValue(self, version, checksum):
+        data=self._execute("SELECT value FROM %s WHERE version=? AND checksum=?;" % self.table,
+                           (version,checksum))
+        row=data.fetchone()
+        if row != None:
+            return row[0]
+        else:
+            #no value found, try to insert
+            self._execute("INSERT INTO %s VALUES (?, ?, (select ifnull(max(value)+1,0) from %s where version=?));" 
+                           % (self.table,self.table),
+                           (version,checksum,version))
+            data=self._execute("SELECT value FROM %s WHERE version=? AND checksum=?;" % self.table,
+                               (version,checksum))
+            row=data.fetchone()
+            if row != None:
+                return row[0]
+            else:
+                raise NotFoundError
+
+class PRData(object):
+    """Object representing the PR database"""
+    def __init__(self, filename):
+        self.filename=os.path.abspath(filename)
+        #build directory hierarchy
+        try:
+            os.makedirs(os.path.dirname(self.filename))
+        except OSError as e:
+            if e.errno != errno.EEXIST:
+                raise e
+        self.connection=sqlite3.connect(self.filename, timeout=5,
+                                          isolation_level=None)
+        self.cursor=self.connection.cursor()
+        self._tables={}
+
+    def __del__(self):
+        print "PRData: closing DB %s" % self.filename
+        self.connection.close()
+
+    def __getitem__(self,tblname):
+        if not isinstance(tblname, basestring):
+            raise TypeError("tblname argument must be a string, not '%s'" %
+                            type(tblname))
+        if tblname in self._tables:
+            return self._tables[tblname]
+        else:
+            tableobj = self._tables[tblname] = PRTable(self.cursor, tblname)
+            return tableobj
+
+    def __delitem__(self, tblname):
+        if tblname in self._tables:
+            del self._tables[tblname]
+        logging.info("drop table %s" % (tblname))
+        self.cursor.execute("DROP TABLE IF EXISTS %s;" % tblname) 
diff --git a/lib/prserv/serv.py b/lib/prserv/serv.py
new file mode 100644
index 000000000..ecafe4f94
--- /dev/null
+++ b/lib/prserv/serv.py
@@ -0,0 +1,198 @@
+import os,sys,logging
+import signal,time, atexit
+from SimpleXMLRPCServer import SimpleXMLRPCServer, SimpleXMLRPCRequestHandler
+import xmlrpclib,sqlite3
+
+import bb.server.xmlrpc
+import prserv
+import prserv.db
+
+if sys.hexversion < 0x020600F0:
+    print("Sorry, python 2.6 or later is required.")
+    sys.exit(1)
+
+class Handler(SimpleXMLRPCRequestHandler):
+    def _dispatch(self,method,params):
+        try:
+            value=self.server.funcs[method](*params)
+        except:
+            import traceback
+            traceback.print_exc()
+            raise
+        return value
+
+class PRServer(SimpleXMLRPCServer):
+    pidfile="/tmp/PRServer.pid"
+    def __init__(self, dbfile, logfile, interface, daemon=True):
+        ''' constructor '''
+        SimpleXMLRPCServer.__init__(self, interface,
+                                    requestHandler=SimpleXMLRPCRequestHandler,
+                                    logRequests=False, allow_none=True)
+        self.dbfile=dbfile
+        self.daemon=daemon
+        self.logfile=logfile
+        self.host, self.port = self.socket.getsockname()
+        self.db=prserv.db.PRData(dbfile)
+        self.table=self.db["PRMAIN"]
+
+        self.register_function(self.getPR, "getPR")
+        self.register_function(self.quit, "quit")
+        self.register_function(self.ping, "ping")
+        self.register_introspection_functions()
+
+    def ping(self):
+        return not self.quit
+ 
+    def getPR(self, version, checksum):
+        try:
+            return self.table.getValue(version,checksum)
+        except prserv.NotFoundError:
+            logging.error("can not find value for (%s, %s)",version,checksum)
+            return None
+        except sqlite3.Error as exc:
+            logging.error(str(exc))
+            return None
+
+    def quit(self):
+        self.quit=True
+        return
+
+    def _serve_forever(self):
+        self.quit = False
+        self.timeout = 0.5
+        while not self.quit:
+            self.handle_request()
+
+        logging.info("PRServer: stopping...")
+        self.server_close()
+        return
+
+    def start(self):
+        if self.daemon is True:
+            logging.info("PRServer: starting daemon...")
+            self.daemonize()
+        else:
+            logging.info("PRServer: starting...")
+            self._serve_forever()
+
+    def delpid(self):
+        os.remove(PRServer.pidfile)
+
+    def daemonize(self):
+        """
+        See Advanced Programming in the UNIX, Sec 13.3
+        """
+        os.umask(0)
+
+        try:
+            pid = os.fork()
+            if pid > 0: 
+                sys.exit(0)
+        except OSError,e:
+            sys.stderr.write("1st fork failed: %d %s\n" % (e.errno, e.strerror))
+            sys.exit(1)
+
+        os.setsid()
+        """
+        fork again to make sure the daemon is not session leader, 
+        which prevents it from acquiring controlling terminal
+        """
+        try:
+            pid = os.fork()
+            if pid > 0: #parent
+                sys.exit(0)
+        except OSError,e:
+            sys.stderr.write("2nd fork failed: %d %s\n" % (e.errno, e.strerror))
+            sys.exit(1)
+
+        os.chdir("/")
+
+        sys.stdout.flush()
+        sys.stderr.flush()
+        si = file('/dev/null', 'r')
+        so = file(self.logfile, 'a+')
+        se = so
+        os.dup2(si.fileno(),sys.stdin.fileno())
+        os.dup2(so.fileno(),sys.stdout.fileno())
+        os.dup2(se.fileno(),sys.stderr.fileno())
+
+        # write pidfile
+        atexit.register(self.delpid)
+        pid = str(os.getpid()) 
+        pf = file(PRServer.pidfile, 'w+')
+        pf.write("%s\n" % pid)
+        pf.write("%s\n" % self.host)
+        pf.write("%s\n" % self.port)
+        pf.close()
+
+        self._serve_forever()
+
+class PRServerConnection():
+    def __init__(self, host, port):
+        self.connection = bb.server.xmlrpc._create_server(host, port)
+        self.host = host
+        self.port = port
+
+    def terminate(self):
+        # Don't wait for server indefinitely
+        import socket
+        socket.setdefaulttimeout(2)
+        try:
+            self.connection.quit()
+        except:
+            pass
+
+    def getPR(self, version, checksum):
+        return self.connection.getPR(version, checksum)
+
+    def ping(self):
+        return self.connection.ping()
+
+def start_daemon(options):
+    try:
+        pf = file(PRServer.pidfile,'r')
+        pid = int(pf.readline().strip())
+        pf.close()
+    except IOError:
+        pid = None
+
+    if pid:
+        sys.stderr.write("pidfile %s already exist. Daemon already running?\n"
+                            % PRServer.pidfile)
+        sys.exit(1)
+
+    server = PRServer(options.dbfile, interface=(options.host, options.port),
+                      logfile=os.path.abspath(options.logfile))
+    server.start()
+
+def stop_daemon():
+    try:
+        pf = file(PRServer.pidfile,'r')
+        pid = int(pf.readline().strip())
+        host = pf.readline().strip()
+        port = int(pf.readline().strip())
+        pf.close()
+    except IOError:
+        pid = None
+
+    if not pid:
+        sys.stderr.write("pidfile %s does not exist. Daemon not running?\n"
+                        % PRServer.pidfile)
+        sys.exit(1)
+
+    PRServerConnection(host,port).terminate()
+    time.sleep(0.5)
+
+    try:
+        while 1:
+            os.kill(pid,signal.SIGTERM)
+            time.sleep(0.1)
+    except OSError, err:
+        err = str(err)
+        if err.find("No such process") > 0:
+            if os.path.exists(PRServer.pidfile):
+                os.remove(PRServer.pidfile)
+        else:
+            print err
+            sys.exit(1)
+