tests: Adding example cases for topojson

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

Example JSON and test cases for 3 types being added:
1. Single link between routers
2. Multiple linke between routers.
3. BGP session over loopback interface

10 files changed, 1055 insertions, 0 deletions

diff --git a/tests/topotests/example-topojson-test/__init__.py b/tests/topotests/example-topojson-test/__init__.py
new file mode 100755
index 000000000..e69de29bb
--- /dev/null
+++ b/tests/topotests/example-topojson-test/__init__.py
diff --git a/tests/topotests/example-topojson-test/test_topo_json_multiple_links/__init__.py b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/__init__.py
new file mode 100755
index 000000000..e69de29bb
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/__init__.py
diff --git a/tests/topotests/example-topojson-test/test_topo_json_multiple_links/example_topojson_multiple_links.json b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/example_topojson_multiple_links.json
new file mode 100644
index 000000000..3968348b1
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/example_topojson_multiple_links.json
@@ -0,0 +1,152 @@
+{
+    "ipv4base": "10.0.0.0",
+    "ipv4mask": 30,
+    "ipv6base": "fd00::",
+    "ipv6mask": 64,
+    "link_ip_start": {
+        "ipv4": "10.0.0.0",
+        "v4mask": 30,
+        "ipv6": "fd00::",
+        "v6mask": 64
+    },
+    "lo_prefix": {
+        "ipv4": "1.0.",
+        "v4mask": 32,
+        "ipv6": "2001:DB8:F::",
+        "v6mask": 128
+    },
+    "routers": {
+        "r1": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2-link1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r2-link2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "r1-link1": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        },
+        "r2": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r1-link1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r1-link2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r3-link1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r3-link2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "redistribute": [
+                                {
+                                    "redist_type": "static"
+                                }
+                            ],
+                            "neighbor": {
+                                "r1": {
+                                    "dest_link": {
+                                        "r2-link1": {}
+                                    }
+                                },
+                                "r3": {
+                                    "dest_link": {
+                                        "r2-link1": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "100.0.20.1/32",
+                    "no_of_ip": 9,
+                    "admin_distance": 100,
+                    "next_hop": "10.0.0.1"
+                }
+            ]
+        },
+        "r3": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2-link1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r2-link2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "r3-link1": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "10.0.0.1/30",
+                    "next_hop": "10.0.0.5"
+                }
+            ]
+        }
+    }
+}
+
diff --git a/tests/topotests/example-topojson-test/test_topo_json_multiple_links/test_example_topojson_multiple_links.py b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/test_example_topojson_multiple_links.py
new file mode 100755
index 000000000..aff8874f9
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_multiple_links/test_example_topojson_multiple_links.py
@@ -0,0 +1,194 @@
+#!/usr/bin/env python
+
+#
+# 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.
+#
+
+"""
+<example>.py: Test <example tests>.
+"""
+
+import os
+import sys
+import json
+import time
+import inspect
+import pytest
+
+# Save the Current Working Directory to find configuration files.
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, '../'))
+sys.path.append(os.path.join(CWD, '../../'))
+
+# pylint: disable=C0413
+from lib.topogen import Topogen, get_topogen
+
+# Required to instantiate the topology builder class.
+from mininet.topo import Topo
+
+# Import topoJson from lib, to create topology and initial configuration
+from lib.common_config import (
+    start_topology, stop_topology, write_test_header,
+    write_test_footer, verify_rib
+)
+from lib.topolog import logger
+from lib.bgp import (
+    verify_bgp_convergence
+)
+from lib.topojson import build_topo_from_json, build_config_from_json
+
+# Reading the data from JSON File for topology and configuration creation
+jsonFile = "{}/example_topojson_multiple_links.json".format(CWD)
+try:
+    with open(jsonFile, 'r') as topoJson:
+        topo = json.load(topoJson)
+except IOError:
+    assert False, "Could not read file {}".format(jsonFile)
+
+# Global variables
+bgp_convergence = False
+input_dict = {}
+
+
+class TemplateTopo(Topo):
+    """
+    Test topology builder
+
+    * `Topo`: Topology object
+    """
+
+    def build(self, *_args, **_opts):
+        "Build function"
+        tgen = get_topogen(self)
+
+        # This function only purpose is to create topology
+        # as defined in input json file.
+        #
+        # Example
+        #
+        # Creating 2 routers having 2 links in between,
+        # one is used to establised BGP neighborship
+
+        # Building topology from json file
+        build_topo_from_json(tgen, topo)
+
+
+def setup_module(mod):
+    """
+    Sets up the pytest environment
+
+    * `mod`: module name
+    """
+
+    testsuite_run_time = time.asctime(time.localtime(time.time()))
+    logger.info("Testsuite start time: {}".format(testsuite_run_time))
+    logger.info("=" * 40)
+
+    logger.info("Running setup_module to create topology")
+
+    # This function initiates the topology build with Topogen...
+    tgen = Topogen(TemplateTopo, mod.__name__)
+    # ... and here it calls Mininet initialization functions.
+
+    # Starting topology, create tmp files which are loaded to routers
+    #  to start deamons and then start routers
+    start_topology(tgen)
+
+    # This function only purpose is to create configuration
+    # as defined in input json file.
+    #
+    # Example
+    #
+    # Creating configuration defined in input JSON
+    # file, example, BGP config, interface config, static routes
+    # config, prefix list config
+
+    # Creating configuration from JSON
+    build_config_from_json(tgen, topo)
+
+    logger.info("Running setup_module() done")
+
+
+def teardown_module(mod):
+    """
+    Teardown the pytest environment
+
+    * `mod`: module name
+    """
+
+    logger.info("Running teardown_module to delete topology")
+
+    tgen = get_topogen()
+
+    # Stop toplogy and Remove tmp files
+    stop_topology(tgen)
+
+
+def test_bgp_convergence(request):
+    " Test BGP daemon convergence "
+
+    tgen = get_topogen()
+    global bgp_convergence
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Don't run this test if we have any failure.
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    # Api call verify whether BGP is converged
+    bgp_convergence = verify_bgp_convergence(tgen, topo)
+    assert bgp_convergence is True, "test_bgp_convergence failed.. \n" \
+                                    " Error: {}".format(bgp_convergence)
+
+    logger.info("BGP is converged successfully \n")
+    write_test_footer(tc_name)
+
+
+def test_static_routes(request):
+    " Test to create and verify static routes. "
+
+    tgen = get_topogen()
+    if bgp_convergence is not True:
+        pytest.skip('skipped because of BGP Convergence failure')
+
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Static routes are created as part of initial configuration,
+    # verifying RIB
+    dut = 'r3'
+    protocol = 'bgp'
+    next_hop = '10.0.0.1'
+    input_dict = {"r1": topo["routers"]["r1"]}
+
+    # Uncomment below to debug
+    # tgen.mininet_cli()
+    result = verify_rib(tgen, 'ipv4', dut, input_dict, next_hop=next_hop)
+    assert result is True, "Testcase {} :Failed \n Error: {}". \
+        format(tc_name, result)
+
+    write_test_footer(tc_name)
+
+
+if __name__ == '__main__':
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link/__init__.py b/tests/topotests/example-topojson-test/test_topo_json_single_link/__init__.py
new file mode 100755
index 000000000..e69de29bb
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link/__init__.py
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link/example_topojson.json b/tests/topotests/example-topojson-test/test_topo_json_single_link/example_topojson.json
new file mode 100644
index 000000000..629d2d6d7
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link/example_topojson.json
@@ -0,0 +1,153 @@
+{
+    "ipv4base": "10.0.0.0",
+    "ipv4mask": 30,
+    "ipv6base": "fd00::",
+    "ipv6mask": 64,
+    "link_ip_start": {
+        "ipv4": "10.0.0.0",
+        "v4mask": 30,
+        "ipv6": "fd00::",
+        "v6mask": 64
+    },
+    "lo_prefix": {
+        "ipv4": "1.0.",
+        "v4mask": 32,
+        "ipv6": "2001:DB8:F::",
+        "v6mask": 128
+    },
+    "routers": {
+        "r1": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r3": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "r1": {}
+                                    }
+                                },
+                                "r3": {
+                                    "dest_link": {
+                                        "r1": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        },
+        "r2": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r3": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "redistribute": [
+                                {
+                                    "redist_type": "static"
+                                }
+                            ],
+                            "neighbor": {
+                                "r1": {
+                                    "dest_link": {
+                                        "r2": {}
+                                    }
+                                },
+                                "r3": {
+                                    "dest_link": {
+                                        "r2": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "100.0.20.1/32",
+                    "no_of_ip": 9,
+                    "admin_distance": 100,
+                    "next_hop": "10.0.0.1"
+                }
+            ]
+        },
+        "r3": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "r3": {}
+                                    }
+                                },
+                                "r1": {
+                                    "dest_link": {
+                                        "r3": {}
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "10.0.0.1/30",
+                    "next_hop": "10.0.0.5"
+                }
+            ]
+        }
+    }
+}
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link/test_example_topojson.py b/tests/topotests/example-topojson-test/test_topo_json_single_link/test_example_topojson.py
new file mode 100755
index 000000000..592174bae
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link/test_example_topojson.py
@@ -0,0 +1,190 @@
+#!/usr/bin/env python
+
+#
+# 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.
+#
+
+"""
+<example>.py: Test <example tests>.
+"""
+
+import os
+import sys
+import time
+import json
+import pytest
+
+# Save the Current Working Directory to find configuration files.
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, '../'))
+sys.path.append(os.path.join(CWD, '../../'))
+
+# pylint: disable=C0413
+from lib.topogen import Topogen,  get_topogen
+
+# Required to instantiate the topology builder class.
+from mininet.topo import Topo
+
+# Import topoJson from lib, to create topology and initial configuration
+from lib.common_config import (
+    start_topology, stop_topology, write_test_header,
+    write_test_footer, verify_rib
+)
+from lib.topolog import logger
+from lib.bgp import (
+    verify_bgp_convergence
+)
+from lib.topojson import build_topo_from_json, build_config_from_json
+
+# Reading the data from JSON File for topology and configuration creation
+jsonFile = "{}/example_topojson.json".format(CWD)
+
+try:
+    with open(jsonFile, 'r') as topoJson:
+        topo = json.load(topoJson)
+except IOError:
+    assert False, "Could not read file {}".format(jsonFile)
+
+# Global variables
+bgp_convergence = False
+input_dict = {}
+
+class TemplateTopo(Topo):
+    """
+    Test topology builder
+
+    * `Topo`: Topology object
+    """
+
+    def build(self, *_args, **_opts):
+        "Build function"
+        tgen = get_topogen(self)
+
+        # This function only purpose is to create topology
+        # as defined in input json file.
+        #
+        # Example
+        #
+        # Creating 2 routers having single links in between,
+        # which is used to establised BGP neighborship
+
+        # Building topology from json file
+        build_topo_from_json(tgen, topo)
+
+def setup_module(mod):
+    """
+    Sets up the pytest environment
+
+    * `mod`: module name
+    """
+
+    testsuite_run_time = time.asctime(time.localtime(time.time()))
+    logger.info("Testsuite start time: {}".format(testsuite_run_time))
+    logger.info("="*40)
+
+    logger.info("Running setup_module to create topology")
+
+    # This function initiates the topology build with Topogen...
+    tgen = Topogen(TemplateTopo, mod.__name__)
+    # ... and here it calls Mininet initialization functions.
+
+    # Starting topology, create tmp files which are loaded to routers
+    #  to start deamons and then start routers
+    start_topology(tgen)
+
+    # This function only purpose is to create configuration
+    # as defined in input json file.
+    #
+    # Example
+    #
+    # Creating configuration defined in input JSON
+    # file, example, BGP config, interface config, static routes
+    # config, prefix list config
+
+    # Creating configuration from JSON
+    build_config_from_json(tgen, topo)
+
+    logger.info("Running setup_module() done")
+
+def teardown_module(mod):
+    """
+    Teardown the pytest environment
+
+    * `mod`: module name
+    """
+
+    logger.info("Running teardown_module to delete topology")
+
+    tgen = get_topogen()
+
+    # Stop toplogy and Remove tmp files
+    stop_topology(tgen)
+
+
+def test_bgp_convergence(request):
+    " Test BGP daemon convergence "
+
+    tgen = get_topogen()
+    global bgp_convergence
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Don't run this test if we have any failure.
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    # Api call verify whether BGP is converged
+    bgp_convergence = verify_bgp_convergence(tgen, topo)
+    assert bgp_convergence is True, "test_bgp_convergence failed.. \n"\
+                                    " Error: {}".format(bgp_convergence)
+
+    logger.info("BGP is converged successfully \n")
+    write_test_footer(tc_name)
+
+
+def test_static_routes(request):
+    " Test to create and verify static routes. "
+
+    tgen = get_topogen()
+    if bgp_convergence is not True:
+        pytest.skip('skipped because of BGP Convergence failure')
+
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Static routes are created as part of initial configuration,
+    # verifying RIB
+    dut = 'r3'
+    next_hop = '10.0.0.1'
+    input_dict = {"r1": topo["routers"]["r1"]}
+
+    # Uncomment below to debug
+    # tgen.mininet_cli()
+    result = verify_rib(tgen, 'ipv4', dut, input_dict, next_hop=next_hop)
+    assert result is True, "Testcase {} :Failed \n Error: {}". \
+        format(tc_name, result)
+
+    write_test_footer(tc_name)
+
+
+if __name__ == '__main__':
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/__init__.py b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/__init__.py
new file mode 100755
index 000000000..e69de29bb
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/__init__.py
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/example_topojson.json b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/example_topojson.json
new file mode 100644
index 000000000..c76c6264b
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/example_topojson.json
@@ -0,0 +1,161 @@
+{
+    "ipv4base": "10.0.0.0",
+    "ipv4mask": 30,
+    "ipv6base": "fd00::",
+    "ipv6mask": 64,
+    "link_ip_start": {
+        "ipv4": "10.0.0.0",
+        "v4mask": 30,
+        "ipv6": "fd00::",
+        "v6mask": 64
+    },
+    "lo_prefix": {
+        "ipv4": "1.0.",
+        "v4mask": 32,
+        "ipv6": "2001:DB8:F::",
+        "v6mask": 128
+    },
+    "routers": {
+        "r1": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "lo": {
+                                            "source_link": "lo"
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "1.0.2.17/32",
+                    "next_hop": "10.0.0.2"
+                }
+            ]
+        },
+        "r2": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r1": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                },
+                "r3": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "redistribute": [
+                                {
+                                    "redist_type": "static"
+                                }
+                            ],
+                            "neighbor": {
+                                "r1": {
+                                    "dest_link": {
+                                        "lo": {
+                                            "source_link": "lo"
+                                        }
+                                    }
+                                },
+                                "r3": {
+                                    "dest_link": {
+                                        "lo": {
+                                            "source_link": "lo"
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "100.0.20.1/32",
+                    "no_of_ip": 9,
+                    "admin_distance": 100,
+                    "next_hop": "10.0.0.1"
+                },
+                {
+                    "network": "1.0.1.17/32",
+                    "next_hop": "10.0.0.1"
+                },
+                {
+                    "network": "1.0.3.17/32",
+                    "next_hop": "10.0.0.6"
+                }
+            ]
+        },
+        "r3": {
+            "links": {
+                "lo": {
+                    "ipv4": "auto",
+                    "ipv6": "auto",
+                    "type": "loopback"
+                },
+                "r2": {
+                    "ipv4": "auto",
+                    "ipv6": "auto"
+                }
+            },
+            "bgp": {
+                "local_as": "100",
+                "address_family": {
+                    "ipv4": {
+                        "unicast": {
+                            "neighbor": {
+                                "r2": {
+                                    "dest_link": {
+                                        "lo": {
+                                            "source_link": "lo"
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            },
+            "static_routes": [
+                {
+                    "network": "1.0.2.17/32",
+                    "next_hop": "10.0.0.5"
+                },
+                {
+                    "network": "10.0.0.1/30",
+                    "next_hop": "10.0.0.5"
+                }
+            ]
+        }
+    }
+}
diff --git a/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/test_example_topojson.py b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/test_example_topojson.py
new file mode 100755
index 000000000..c5ff7c80e
--- /dev/null
+++ b/tests/topotests/example-topojson-test/test_topo_json_single_link_loopback/test_example_topojson.py
@@ -0,0 +1,205 @@
+#!/usr/bin/env python
+
+#
+# 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.
+#
+
+"""
+<example>.py: Test <example tests>.
+"""
+
+import os
+import sys
+import time
+import json
+import inspect
+import pytest
+
+# Save the Current Working Directory to find configuration files.
+CWD = os.path.dirname(os.path.realpath(__file__))
+sys.path.append(os.path.join(CWD, '../'))
+sys.path.append(os.path.join(CWD, '../../'))
+
+# pylint: disable=C0413
+# Import topogen and topotest helpers
+from lib.topogen import Topogen,  get_topogen
+
+# Required to instantiate the topology builder class.
+from mininet.topo import Topo
+
+# Import topoJson from lib, to create topology and initial configuration
+from lib.common_config import (
+    start_topology, stop_topology, write_test_header,
+    write_test_footer, verify_rib
+)
+from lib.topolog import logger
+from lib.bgp import (
+    verify_bgp_convergence
+)
+from lib.topojson import build_topo_from_json, build_config_from_json
+
+# Reading the data from JSON File for topology and configuration creation
+jsonFile = "{}/example_topojson.json".format(CWD)
+
+try:
+    with open(jsonFile, 'r') as topoJson:
+        topo = json.load(topoJson)
+except IOError:
+    assert False, "Could not read file {}".format(jsonFile)
+
+# Global variables
+bgp_convergence = False
+input_dict = {}
+
+
+class TemplateTopo(Topo):
+    """
+    Test topology builder
+
+    * `Topo`: Topology object
+    """
+
+    def build(self, *_args, **_opts):
+        "Build function"
+        tgen = get_topogen(self)
+
+        # This function only purpose is to create topology
+        # as defined in input json file.
+        #
+        # Example
+        #
+        # Creating 2 routers having single links in between,
+        # which is used to establised BGP neighborship
+
+        # Building topology from json file
+        build_topo_from_json(tgen, topo)
+
+
+def setup_module(mod):
+    """
+    Sets up the pytest environment
+
+    * `mod`: module name
+    """
+
+    testsuite_run_time = time.asctime(time.localtime(time.time()))
+    logger.info("Testsuite start time: {}".format(testsuite_run_time))
+    logger.info("="*40)
+
+    logger.info("Running setup_module to create topology")
+
+    # This function initiates the topology build with Topogen...
+    tgen = Topogen(TemplateTopo, mod.__name__)
+    # ... and here it calls Mininet initialization functions.
+
+    # Starting topology, create tmp files which are loaded to routers
+    #  to start deamons and then start routers
+    start_topology(tgen)
+
+    # This function only purpose is to create configuration
+    # as defined in input json file.
+    #
+    # Example
+    #
+    # Creating configuration defined in input JSON
+    # file, example, BGP config, interface config, static routes
+    # config, prefix list config
+
+    # Creating configuration from JSON
+    build_config_from_json(tgen, topo)
+
+    logger.info("Running setup_module() done")
+
+
+def teardown_module(mod):
+    """
+    Teardown the pytest environment
+
+    * `mod`: module name
+    """
+
+    logger.info("Running teardown_module to delete topology")
+
+    tgen = get_topogen()
+
+    # Stop toplogy and Remove tmp files
+    stop_topology(tgen)
+
+
+def test_bgp_convergence(request):
+    " Test BGP daemon convergence "
+
+    tgen = get_topogen()
+    global bgp_convergence
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Don't run this test if we have any failure.
+    if tgen.routers_have_failure():
+        pytest.skip(tgen.errors)
+
+    # Api call verify whether BGP is converged
+    bgp_convergence = verify_bgp_convergence(tgen, topo)
+    assert bgp_convergence is True, "test_bgp_convergence failed.. \n"\
+                                    " Error: {}".format(bgp_convergence)
+
+    logger.info("BGP is converged successfully \n")
+    write_test_footer(tc_name)
+
+
+def test_static_routes(request):
+    " Test to create and verify static routes. "
+
+    tgen = get_topogen()
+    if bgp_convergence is not True:
+        pytest.skip('skipped because of BGP Convergence failure')
+
+    # test case name
+    tc_name = request.node.name
+    write_test_header(tc_name)
+
+    # Static routes are created as part of initial configuration,
+    # verifying RIB
+    dut = 'r3'
+    next_hop = '10.0.0.1'
+    input_dict = {
+        "r1": {
+            "static_routes": [
+                {
+                    "network": "100.0.20.1/32",
+                    "no_of_ip": 9,
+                    "admin_distance": 100,
+                    "next_hop": "10.0.0.1"
+                }
+            ]
+        }
+    }
+    # Uncomment below to debug
+    # tgen.mininet_cli()
+    result = verify_rib(tgen, 'ipv4', dut, input_dict, next_hop=next_hop)
+    assert result is True, "Testcase {} :Failed \n Error: {}". \
+        format(tc_name, result)
+
+    write_test_footer(tc_name)
+
+
+if __name__ == '__main__':
+    args = ["-s"] + sys.argv[1:]
+    sys.exit(pytest.main(args))