tests: Intial commit for topojson

Signed-off-by: Ashish Pant <ashish12pant@gmail.com>

Adding JSON parser for creating router and assinging ip addresses to
each interface

2 files changed, 188 insertions, 0 deletions

diff --git a/tests/topotests/lib/common_config.py b/tests/topotests/lib/common_config.py
new file mode 100644
index 000000000..ecd4c0e4b
--- /dev/null
+++ b/tests/topotests/lib/common_config.py
@@ -0,0 +1,37 @@
+#
+# Copyright (c) 2019 by VMware, Inc. ("VMware")
+# Used Copyright (c) 2018 by Network Device Education Foundation, Inc.
+# ("NetDEF") in this file.
+#
+# Permission to use, copy, modify, and/or distribute this software
+# for any purpose with or without fee is hereby granted, provided
+# that the above copyright notice and this permission notice appear
+# in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND VMWARE DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL VMWARE BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
+# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+# ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+# OF THIS SOFTWARE.
+#
+
+
+def number_to_row(routerName):
+    """
+    Returns the number for the router.
+    Calculation based on name a0 = row 0, a1 = row 1, b2 = row 2, z23 = row 23
+    etc
+    """
+    return int(routerName[1:])
+
+
+def number_to_column(routerName):
+    """
+    Returns the number for the router.
+    Calculation based on name a0 = columnn 0, a1 = column 0, b2= column 1,
+    z23 = column 26 etc
+    """
+    return ord(routerName[0]) - 97
\ No newline at end of file
diff --git a/tests/topotests/lib/topojson.py b/tests/topotests/lib/topojson.py
new file mode 100644
index 000000000..b76fb6106
--- /dev/null
+++ b/tests/topotests/lib/topojson.py
@@ -0,0 +1,151 @@
+#
+# Modified work Copyright (c) 2019 by VMware, Inc. ("VMware")
+# Original work Copyright (c) 2018 by Network Device Education
+# Foundation, Inc. ("NetDEF")
+#
+# Permission to use, copy, modify, and/or distribute this software
+# for any purpose with or without fee is hereby granted, provided
+# that the above copyright notice and this permission notice appear
+# in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND VMWARE DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL VMWARE BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
+# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+# ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+# OF THIS SOFTWARE.
+#
+
+
+from json import dumps as json_dumps
+import ipaddr
+
+# Import topogen and topotest helpers
+from lib.topolog import logger
+
+# Required to instantiate the topology builder class.
+from lib.common_config import (number_to_row, number_to_column)
+
+
+def build_topo_from_json(tgen, topo):
+    """
+    Reads configuration from JSON file. Adds routers, creates interface
+    names dynamically and link routers as defined in JSON to create
+    topology. Assigns IPs dynamically to all interfaces of each router.
+
+    * `tgen`: Topogen object
+    * `topo`: json file data
+    """
+
+    listRouters = []
+    for routerN in sorted(topo['routers'].iteritems()):
+        logger.info('Topo: Add router {}'.format(routerN[0]))
+        tgen.add_router(routerN[0])
+        listRouters.append(routerN[0])
+
+    listRouters.sort()
+    if 'ipv4base' in topo:
+        ipv4Next = ipaddr.IPv4Address(topo['link_ip_start']['ipv4'])
+        ipv4Step = 2 ** (32 - topo['link_ip_start']['v4mask'])
+        if topo['link_ip_start']['v4mask'] < 32:
+            ipv4Next += 1
+    if 'ipv6base' in topo:
+        ipv6Next = ipaddr.IPv6Address(topo['link_ip_start']['ipv6'])
+        ipv6Step = 2 ** (128 - topo['link_ip_start']['v6mask'])
+        if topo['link_ip_start']['v6mask'] < 127:
+            ipv6Next += 1
+    for router in listRouters:
+        topo['routers'][router]['nextIfname'] = 0
+
+    while listRouters != []:
+        curRouter = listRouters.pop(0)
+        # Physical Interfaces
+        if 'links' in topo['routers'][curRouter]:
+            def link_sort(x):
+                if x == 'lo':
+                    return 0
+                elif 'link' in x:
+                    return int(x.split('-link')[1])
+                else:
+                    return int(x.split('r')[1])
+            for destRouterLink, data in sorted(topo['routers'][curRouter]['links']. \
+                                               iteritems(),
+                                               key=lambda x: link_sort(x[0])):
+                currRouter_lo_json = \
+                    topo['routers'][curRouter]['links'][destRouterLink]
+                # Loopback interfaces
+                if 'type' in data and data['type'] == 'loopback':
+                    if 'ipv4' in currRouter_lo_json and \
+                            currRouter_lo_json['ipv4'] == 'auto':
+                        currRouter_lo_json['ipv4'] = '{}{}.{}/{}'. \
+                            format(topo['lo_prefix']['ipv4'], number_to_row(curRouter), \
+                                   number_to_column(curRouter), topo['lo_prefix']['v4mask'])
+                    if 'ipv6' in currRouter_lo_json and \
+                            currRouter_lo_json['ipv6'] == 'auto':
+                        currRouter_lo_json['ipv6'] = '{}{}:{}/{}'. \
+                            format(topo['lo_prefix']['ipv6'], number_to_row(curRouter), \
+                                   number_to_column(curRouter), topo['lo_prefix']['v6mask'])
+
+                if "-" in destRouterLink:
+                    # Spliting and storing destRouterLink data in tempList
+                    tempList = destRouterLink.split("-")
+
+                    # destRouter
+                    destRouter = tempList.pop(0)
+
+                    # Current Router Link
+                    tempList.insert(0, curRouter)
+                    curRouterLink = "-".join(tempList)
+                else:
+                    destRouter = destRouterLink
+                    curRouterLink = curRouter
+
+                if destRouter in listRouters:
+                    currRouter_link_json = \
+                        topo['routers'][curRouter]['links'][destRouterLink]
+                    destRouter_link_json = \
+                        topo['routers'][destRouter]['links'][curRouterLink]
+
+                    # Assigning name to interfaces
+                    currRouter_link_json['interface'] = \
+                        '{}-{}-eth{}'.format(curRouter, destRouter, topo['routers'] \
+                            [curRouter]['nextIfname'])
+                    destRouter_link_json['interface'] = \
+                        '{}-{}-eth{}'.format(destRouter, curRouter, topo['routers'] \
+                            [destRouter]['nextIfname'])
+
+                    topo['routers'][curRouter]['nextIfname'] += 1
+                    topo['routers'][destRouter]['nextIfname'] += 1
+
+                    # Linking routers to each other as defined in JSON file
+                    tgen.gears[curRouter].add_link(tgen.gears[destRouter],
+                        topo['routers'][curRouter]['links'][destRouterLink] \
+                        ['interface'], topo['routers'][destRouter]['links'] \
+                        [curRouterLink]['interface'])
+
+                    # IPv4
+                    if 'ipv4' in currRouter_link_json:
+                        if currRouter_link_json['ipv4'] == 'auto':
+                            currRouter_link_json['ipv4'] = \
+                                '{}/{}'.format(ipv4Next, topo['link_ip_start'][ \
+                                    'v4mask'])
+                            destRouter_link_json['ipv4'] = \
+                                '{}/{}'.format(ipv4Next + 1, topo['link_ip_start'][ \
+                                    'v4mask'])
+                            ipv4Next += ipv4Step
+                    # IPv6
+                    if 'ipv6' in currRouter_link_json:
+                        if currRouter_link_json['ipv6'] == 'auto':
+                            currRouter_link_json['ipv6'] = \
+                                '{}/{}'.format(ipv6Next, topo['link_ip_start'][ \
+                                    'v6mask'])
+                            destRouter_link_json['ipv6'] = \
+                                '{}/{}'.format(ipv6Next + 1, topo['link_ip_start'][ \
+                                    'v6mask'])
+                            ipv6Next = ipaddr.IPv6Address(int(ipv6Next) + ipv6Step)
+
+            logger.debug("Generated link data for router: %s\n%s", curRouter,
+                         json_dumps(topo["routers"][curRouter]["links"],
+                                    indent=4, sort_keys=True)