library/jenkins_node: Allow to work on centos7 by adding xml parser

xmltodict is exactly what I needed, but it's too hard to dig up
for centos7 (and overkill anyway).  Supply an implementation that
allows jenkins XML parsing and use it instead.

Also, use python3 on centos7, and tweak the packages a bit in
examples/builder.yml

Signed-off-by: Dan Mick <dmick@redhat.com>

diff --git a/ansible/examples/builder.yml b/ansible/examples/builder.yml
index a1e099e9248f9352b01c03aad12097e24ec650b2..2953c32e4e50769b97725fcb03a5f99770574865 100644 (file)
--- a/ansible/examples/builder.yml
+++ b/ansible/examples/builder.yml
@@ -119,7 +119,6 @@
           - python3-pip
           - python3-venv
           - python3-virtualenv
-          - python3-xmltodict
       when:
         - ansible_os_family == "Debian"
         - ansible_distribution_major_version|int >= 18
@@ -210,7 +209,6 @@
           - python3-pip
           - python3-devel
           - python3-virtualenv
-          - python3-xmltodict
           - mock
           - podman
         container_service_name: podman
@@ -235,7 +233,6 @@
           - jq
           - python3-pip
           - python3-devel
-          - python3-xmltodict
           - podman
         container_service_name: podman
         container_certs_path: "/etc/containers/certs.d/{{ container_mirror }}"
@@ -291,7 +288,6 @@
           - python2-virtualenv
           - python3-pip
           - python3-virtualenv
-          - python3-xmltodict
           - rpm-build
           - rpmdevtools
           - tig
@@ -801,7 +797,7 @@
     - set_fact:
         pip_version: pip3
         ansible_python_interpreter: /usr/bin/python3
-      when: (ansible_os_family == "RedHat" and ansible_distribution_major_version|int >= 8) or
+      when: (ansible_os_family == "RedHat" and ansible_distribution_major_version|int >= 7) or
             (ansible_os_family == "Debian" and ansible_distribution_major_version|int >= 18) or
             ansible_os_family == "Suse"
       tags:

diff --git a/ansible/library/jenkins_node b/ansible/library/jenkins_node
index 5a3a84016cec8f518f1252b97fb245252213ec54..617daa2455d814b4cedc5151dc7f1f228e21a17b 100644 (file)
--- a/ansible/library/jenkins_node
+++ b/ansible/library/jenkins_node
@@ -102,7 +102,7 @@ EXAMPLES = """
 """
 import ast
 import traceback
-import xmltodict
+import xml.etree.ElementTree as ET
 
 HAS_JENKINS_API = True
 try:
@@ -165,6 +165,117 @@ def sanitize_update_params(kw):
     return invalid, update_kws
 
 
+# our own limited implementation of xmltodict, because
+# that module is hard to find in distro packages
+
+def _create_or_append(d, tag, v):
+    if tag not in d:
+        d[tag] = ''
+
+    if not d[tag]:
+        d[tag] = list((v,))
+    else:
+        d[tag].append(v)
+
+
+def xml_to_dict(e):
+    '''
+    XML element to dict.  Note that multiple occurrences of
+    the same tag are translated to an item where value is a list.
+    '''
+    d = dict()
+    xml_to_dict_worker(e, d)
+    return d
+
+
+def xml_to_dict_worker(e, curdict):
+    subd = None
+    if e.attrib or len(e):
+        curdict[e.tag] = subd = dict()
+
+    if e.attrib:
+        for k,v in e.attrib.items():
+            subd['@'+k] = v
+
+    # XXX maybe don't strip?
+    if e.text:
+        e.text = e.text.strip()
+    if not (len(e)):
+        # if subd exists, there were attributes and/or children,
+        # and text goes into a #text item of subd.
+        # If subd does not exist, there are no children or attrs,
+        # and this text goes into curdict[e.tag] directly.
+        #
+        # Note: multiple text strings are weird in etree; since order
+        # matters, they can't all live in e.text, or even e; they appear in
+        # the 'tail' attribute of subsequent nested elements, if those exist.
+        # That's just too much to handle here, so we ignore any but the
+        # first text string.  That should be fine for Jenkins anyway.
+        if subd:
+            if e.text:
+                # only create an addr for a non-null e.text
+                _create_or_append(subd, '#text', e.text)
+        else:
+            # but fill curdict[e.tag] even if e.text is None
+            _create_or_append(curdict, e.tag, e.text)
+        return
+
+    # there are children; there must have been no text
+    for c in e:
+        xml_to_dict_worker(c, subd)
+
+
+def _scalar_or_list(v):
+    if v and isinstance(v, list):
+        return v
+    if v:
+        # v might be iterable.  Don't iterate it.
+        l = list()
+        l.append(v)
+        return l
+    # v was None
+    return list()
+
+
+def dict_to_xml(d):
+    '''
+    Python dict to xml element, the dual of xml_to_dict()
+    '''
+    if len(d) > 1:
+        raise ValueError
+    # get first item
+    k,v = next(iter(d.items()))
+    e = ET.Element(k)
+    dict_to_xml_worker(e, v)
+    return e
+
+
+def dict_to_xml_worker(e, value):
+    if isinstance(value, dict):
+        # process entire dict, recursing if necessary
+        for k,v in value.items():
+            if k.startswith('@'):
+                e.set(k[1:], v)
+            else:
+                if isinstance(v, dict):
+                    c = ET.Element(k)
+                    e.append(c)
+                    dict_to_xml_worker(c, v)
+                else:
+                    if v is None:
+                        c = ET.Element(k)
+                        e.append(c)
+                        c.text = v
+                    else:
+                        for s in _scalar_or_list(v):
+                            c = ET.Element(k)
+                            c.text = s
+                            e.append(c)
+    else:
+        # wasn't a dict at the call; just set text and return
+        e.text = value
+
+
 def create_or_modify(uri, user, password, name, **kw):
     launcher_params = {}
     launcher_params['credentialsId'] = kw.pop('credentialsId', None)
@@ -180,12 +291,15 @@ def create_or_modify(uri, user, password, name, **kw):
         # select valid config keys, transform a few
         invalid, params = sanitize_update_params(params)
 
-        config = xmltodict.parse(j.get_node_config(name))
+        configstr = j.get_node_config(name)
+        xml_config = ET.fromstring(configstr)
+        config = xml_to_dict(xml_config)
         for k, v in params.items():
             config['slave'][k] = v
-        new_xconfig = xmltodict.unparse(config)
+        new_xconfig = dict_to_xml(config)
+        new_xconfigstr = ET.tostring(new_xconfig, encoding='unicode')
 
-        j.reconfig_node(name, new_xconfig)
+        j.reconfig_node(name, new_xconfigstr)
     else:
         if 'label' in params:
             params['labels'] = params['label']