Added migration script from 1.x to 5.0 configuration files (#1576)

It doesn't do yaml parsing, just line by line string operations. This means
it is not able to transform any yaml syntax, but should work on the most
common cases.

On the plus side, it uses only python standard library modules and it keeps
the comments as in the original file. Related to #1488.

libbeat/scripts/migrate_beat_config_1_x_to_5_0.py

@@ -0,0 +1,183 @@
+#!/usr/bin/env python
+import argparse
+import os
+
+
+def migrate_topbeat(content):
+    """
+    Changes top level `input:` into `topbeat:`
+    """
+    lines = content.splitlines()
+    outlines = []
+    for line in lines:
+        if line.startswith("input:"):
+            outlines.append("topbeat:")
+        else:
+            outlines.append(line)
+    return "\n".join(outlines) + "\n"
+
+
+def migrate_packetbeat(content):
+    """
+    Changes things like `interfaces:` to `packetbeat.interfaces:`
+    at the top level.
+    """
+    sections = ["interfaces", "protocols", "procs", "runoptions"]
+    lines = content.splitlines()
+    outlines = []
+    for line in lines:
+        found = False
+        for sec in sections:
+            if line.startswith(sec + ":"):
+                outlines.append("packetbeat." + line)
+                found = True
+                break
+        if not found:
+            outlines.append(line)
+    return "\n".join(outlines) + "\n"
+
+
+def migrate_shipper(content):
+    """
+    Moves everything under the `shipper:` section to be top level.
+    """
+    lines = content.splitlines()
+    outlines = []
+    state = "out"
+    for line in lines:
+        if state == "out":
+            if line.startswith("shipper:"):
+                state = "in"
+                # eat line
+            else:
+                outlines.append(line)
+        elif state == "in":
+            if line.startswith("  "):
+                outlines.append(line[2:])
+            elif line.startswith("\t"):
+                outlines.append(line[1:])
+            elif line == "":
+                outlines.append(line)
+            else:
+                outlines.append(line)
+                state = "out"
+    return "\n".join(outlines) + "\n"
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Migrates beats configuration from 1.x to 5.0")
+    parser.add_argument("file",
+                        help="Configuration file to migrate")
+    parser.add_argument("--dry", action="store_true",
+                        help="Don't do any changes, just print the" +
+                             " modified config to the screen")
+    args = parser.parse_args()
+
+    with open(args.file, "r") as f:
+        content = f.read()
+        out = migrate_packetbeat(content)
+        out = migrate_topbeat(out)
+        out = migrate_shipper(out)
+
+    if args.dry:
+        print(out)
+    else:
+        os.rename(args.file, args.file + ".bak")
+        print("Backup file created: {}".format(args.file + ".bak"))
+        with open(args.file, "w") as f:
+            f.write(out)
+
+
+if __name__ == "__main__":
+    main()
+
+
+def test_migrate_topbeat():
+    test = """
+input:
+  # In seconds, defines how often to read server statistics
+  period: 10
+
+  # Regular expression to match the processes that are monitored
+  # By default, all the processes are monitored
+  procs: [".*"]
+"""
+    output = migrate_topbeat(test)
+    assert output == """
+topbeat:
+  # In seconds, defines how often to read server statistics
+  period: 10
+
+  # Regular expression to match the processes that are monitored
+  # By default, all the processes are monitored
+  procs: [".*"]
+"""
+
+
+def test_migrate_packetbeat():
+    test = """
+# Select the network interfaces to sniff the data. You can use the "any"
+# keyword to sniff on all connected interfaces.
+interfaces:
+  device: en0
+
+############################# Protocols #######################################
+protocols:
+  dns:
+    # Configure the ports where to listen for DNS traffic. You can disable
+    # the DNS protocol by commenting out the list of ports.
+    ports: [53]
+runoptions:
+procs:
+"""
+
+    output = migrate_packetbeat(test)
+    assert output == """
+# Select the network interfaces to sniff the data. You can use the "any"
+# keyword to sniff on all connected interfaces.
+packetbeat.interfaces:
+  device: en0
+
+############################# Protocols #######################################
+packetbeat.protocols:
+  dns:
+    # Configure the ports where to listen for DNS traffic. You can disable
+    # the DNS protocol by commenting out the list of ports.
+    ports: [53]
+packetbeat.runoptions:
+packetbeat.procs:
+"""
+
+
+def test_migrate_shipper():
+    test = """
+############################# Shipper #########################################
+
+shipper:
+  # The name of the shipper that publishes the network data. It can be used to group
+  # all the transactions sent by a single shipper in the web interface.
+  # If this options is not defined, the hostname is used.
+  name:
+
+  # The tags of the shipper are included in their own field with each
+  # transaction published. Tags make it easy to group servers by different
+  # logical properties.
+  #tags: ["service-X", "web-tier"]
+test:
+"""
+    output = migrate_shipper(test)
+    assert output == """
+############################# Shipper #########################################
+
+# The name of the shipper that publishes the network data. It can be used to group
+# all the transactions sent by a single shipper in the web interface.
+# If this options is not defined, the hostname is used.
+name:
+
+# The tags of the shipper are included in their own field with each
+# transaction published. Tags make it easy to group servers by different
+# logical properties.
+#tags: ["service-X", "web-tier"]
+test:
+"""