From e999929818e5afea4109d4e5878a0cfeab5dd6be Mon Sep 17 00:00:00 2001
From: Tim Byrne <sultan@locehilios.com>
Date: Tue, 1 Oct 2019 08:17:28 -0500
Subject: [PATCH] Change builtin templates to resemble jinja

---
 test/test_unit_template_builtin.py | 84 +++++++++++++++---------------
 yadm                               | 25 +++++----
 2 files changed, 56 insertions(+), 53 deletions(-)

diff --git a/test/test_unit_template_builtin.py b/test/test_unit_template_builtin.py
index ac141e4..4d87a12 100644
--- a/test/test_unit_template_builtin.py
+++ b/test/test_unit_template_builtin.py
@@ -8,56 +8,56 @@ LOCAL_USER = "builtin_Test+@-!^User"
 LOCAL_DISTRO = "builtin_Test+@-!^Distro"
 TEMPLATE = f'''
 start of template
-builtin class  = >YADM_CLASS<
-builtin os     = >YADM_OS<
-builtin host   = >YADM_HOSTNAME<
-builtin user   = >YADM_USER<
-builtin distro = >YADM_DISTRO<
-YADM_IF CLASS="wrongclass1"
+builtin class  = >{{{{yadm.class}}}}<
+builtin os     = >{{{{yadm.os}}}}<
+builtin host   = >{{{{yadm.hostname}}}}<
+builtin user   = >{{{{yadm.user}}}}<
+builtin distro = >{{{{yadm.distro}}}}<
+{{% if yadm.class == "wrongclass1" %}}
 wrong class 1
-YADM_END
-YADM_IF CLASS="{LOCAL_CLASS}"
-Included section for class = YADM_CLASS (YADM_CLASS repeated)
-YADM_END
-YADM_IF CLASS="wrongclass2"
+{{% endif %}}
+{{% if yadm.class == "{LOCAL_CLASS}" %}}
+Included section for class = {{{{yadm.class}}}} ({{{{yadm.class}}}} repeated)
+{{% endif %}}
+{{% if yadm.class == "wrongclass2" %}}
 wrong class 2
-YADM_END
-YADM_IF OS="wrongos1"
+{{% endif %}}
+{{% if yadm.os == "wrongos1" %}}
 wrong os 1
-YADM_END
-YADM_IF OS="{LOCAL_SYSTEM}"
-Included section for os = YADM_OS (YADM_OS repeated)
-YADM_END
-YADM_IF OS="wrongos2"
+{{% endif %}}
+{{% if yadm.os == "{LOCAL_SYSTEM}" %}}
+Included section for os = {{{{yadm.os}}}} ({{{{yadm.os}}}} repeated)
+{{% endif %}}
+{{% if yadm.os == "wrongos2" %}}
 wrong os 2
-YADM_END
-YADM_IF HOSTNAME="wronghost1"
+{{% endif %}}
+{{% if yadm.hostname == "wronghost1" %}}
 wrong host 1
-YADM_END
-YADM_IF HOSTNAME="{LOCAL_HOST}"
-Included section for host = YADM_HOSTNAME (YADM_HOSTNAME repeated)
-YADM_END
-YADM_IF HOSTNAME="wronghost2"
+{{% endif %}}
+{{% if yadm.hostname == "{LOCAL_HOST}" %}}
+Included section for host = {{{{yadm.hostname}}}} ({{{{yadm.hostname}}}} again)
+{{% endif %}}
+{{% if yadm.hostname == "wronghost2" %}}
 wrong host 2
-YADM_END
-YADM_IF USER="wronguser1"
+{{% endif %}}
+{{% if yadm.user == "wronguser1" %}}
 wrong user 1
-YADM_END
-YADM_IF USER="{LOCAL_USER}"
-Included section for user = YADM_USER (YADM_USER repeated)
-YADM_END
-YADM_IF USER="wronguser2"
+{{% endif %}}
+{{% if yadm.user == "{LOCAL_USER}" %}}
+Included section for user = {{{{yadm.user}}}} ({{{{yadm.user}}}} repeated)
+{{% endif %}}
+{{% if yadm.user == "wronguser2" %}}
 wrong user 2
-YADM_END
-YADM_IF DISTRO="wrongdistro1"
+{{% endif %}}
+{{% if yadm.distro == "wrongdistro1" %}}
 wrong distro 1
-YADM_END
-YADM_IF DISTRO="{LOCAL_DISTRO}"
-Included section for distro = YADM_DISTRO (YADM_DISTRO repeated)
-YADM_END
-YADM_IF DISTRO="wrongdistro2"
+{{% endif %}}
+{{% if yadm.distro == "{LOCAL_DISTRO}" %}}
+Included section for distro = {{{{yadm.distro}}}} ({{{{yadm.distro}}}} again)
+{{% endif %}}
+{{% if yadm.distro == "wrongdistro2" %}}
 wrong distro 2
-YADM_END
+{{% endif %}}
 end of template
 '''
 EXPECTED = f'''
@@ -69,9 +69,9 @@ builtin user   = >{LOCAL_USER}<
 builtin distro = >{LOCAL_DISTRO}<
 Included section for class = {LOCAL_CLASS} ({LOCAL_CLASS} repeated)
 Included section for os = {LOCAL_SYSTEM} ({LOCAL_SYSTEM} repeated)
-Included section for host = {LOCAL_HOST} ({LOCAL_HOST} repeated)
+Included section for host = {LOCAL_HOST} ({LOCAL_HOST} again)
 Included section for user = {LOCAL_USER} ({LOCAL_USER} repeated)
-Included section for distro = {LOCAL_DISTRO} ({LOCAL_DISTRO} repeated)
+Included section for distro = {LOCAL_DISTRO} ({LOCAL_DISTRO} again)
 end of template
 '''
 
diff --git a/yadm b/yadm
index a3f9893..2a9e989 100755
--- a/yadm
+++ b/yadm
@@ -279,35 +279,38 @@ function template_builtin() {
   input="$1"
   output="$2"
 
+  # the explicit "space + tab" character class used below is used because not
+  # all versions of awk seem to support the POSIX character classes [[:blank:]]
   awk_pgm=$(cat << "EOF"
 # built-in template processor
 BEGIN {
-  c["CLASS"]    = class
-  c["OS"]       = os
-  c["HOSTNAME"] = host
-  c["USER"]     = user
-  c["DISTRO"]   = distro
+  blank         = "[ 	]"
+  c["class"]    = class
+  c["os"]       = os
+  c["hostname"] = host
+  c["user"]     = user
+  c["distro"]   = distro
   valid         = conditions()
-  end           = "^YADM_END$"
-  skip          = "^YADM_(IF|END$)"
+  end           = "^{%" blank "*endif" blank "*%}$"
+  skip          = "^{%" blank "*(if|endif)"
 }
 { replace_vars() } # variable replacements
 $0 ~ valid, $0 ~ end { if ($0 ~ skip) next } # valid conditional blocks
-/^YADM_IF/, $0 ~ end { next } # invalid conditional blocks
+$0 ~ ("^{%" blank "*if"), $0 ~ end { next } # invalid conditional blocks
 { print }
 
 function replace_vars() {
   for (label in c) {
-    gsub(("YADM_" label), c[label])
+    gsub(("{{" blank "*yadm\\." label blank "*}}"), c[label])
   }
 }
 
 function conditions() {
-  pattern = "^("
+  pattern = "^{%" blank "*if" blank "*("
   for (label in c) {
     value = c[label]
     gsub(/[\\.^$(){}\[\]|*+?]/, "\\\\&", value)
-    pattern = sprintf("%sYADM_IF +%s *= *\"%s\"|", pattern, label, value)
+    pattern = sprintf("%syadm\\.%s" blank "*==" blank "*\"%s\"|", pattern, label, value)
   }
   sub(/\|$/,")",pattern)
   return pattern