more changes based on review...

* Makefile - improve/fix check for required make vars
* resolve-profile.py.in
+ build a list of all regions & probe to see which ones are enabled (unknown if special subscription regions like ap-northeast-3 would show up in this list)
+ expand 'ami_regions' 'ALL' meta key to all enabled regions, 'ALL' key's value is preserved (that is, a value of None or False will disable all regions)
+ warn/remove regions in profile config that are found to be disabled.
+ improve checks for [None, False] values

Makefile

@@ -12,20 +12,29 @@ LEVEL :=
 PACKER := packer
 export PACKER
 
-require_var = $(if $(value $1),,$(error $1=... required))
+
+check_defined = \
+    $(strip $(foreach 1,$1, \
+        $(call __check_defined,$1,$(strip $(value 2)))))
+__check_defined = \
+    $(if $(value $1),, \
+        $(error Undefined $1$(if $2, ($2))$(if $(value @), \
+                required by target `$@')))
+
 
 .PHONY: amis prune release-readme clean
 
 amis: build build/packer.json build/profile/$(PROFILE) build/update-release.py
-	@:$(call require_var, PROFILE)
+	@:$(call check_defined, PROFILE, target profile name)
 	build/make-amis $(PROFILE) $(BUILDS)
 
 prune: build build/prune-amis.py
-	@:$(call require_var, LEVEL)
-	@:$(call require_var, PROFILE)
+	@:$(call check_defined, LEVEL, pruning level)
+	@:$(call check_defined, PROFILE, target profile name)
 	build/prune-amis.py $(LEVEL) $(PROFILE) $(BUILD)
 
 release-readme: build build/gen-release-readme.py
+	@:$(call check_defined, PROFILE, target profile name)
 	@:$(call require_var, PROFILE)
 	build/gen-release-readme.py $(PROFILE)
 
@@ -39,7 +48,7 @@ build/packer.json: build packer.conf
 	build/.py3/bin/pyhocon -i packer.conf -f json > build/packer.json
 
 build/profile/$(PROFILE): build build/resolve-profile.py $(CORE_PROFILES) $(TARGET_PROFILES)
-	@:$(call require_var, PROFILE)
+	@:$(call check_defined, PROFILE, target profile name)
 	build/resolve-profile.py $(PROFILE)
 
 %.py: %.py.in build

profiles/alpine.conf

@@ -18,24 +18,7 @@ alpine {
     all = true    # these AMIs are publicly available
   }
   ami_regions {
-    #ap-east-1       = true    # needs to be enabled first
-    ap-northeast-1  = true
-    ap-northeast-2  = true
-    #ap-northeast-3  = false   # available by subscription only
-    ap-southeast-1  = true
-    ap-southeast-2  = true
-    ap-south-1      = true
-    ca-central-1    = true
-    eu-central-1    = true
-    eu-north-1      = true
-    eu-west-1       = true
-    eu-west-2       = true
-    eu-west-3       = true
-    sa-east-1       = true
-    us-east-1       = true
-    us-east-2       = true
-    us-west-1       = true
-    us-west-2       = true
+    ALL = true
   }
 }
 

profiles/test.conf

@@ -15,6 +15,10 @@ test {
   ami_desc_prefix = "Alpine Test "
   build_region    = "us-west-2"
   build_subnet    = "subnet-033a30d7b5220d177"
+  ami_regions {
+    us-west-1 = true
+    ap-east-1 = true
+  }
 }
 
 # Build definitions

scripts/resolve-profile.py.in

@@ -5,6 +5,8 @@ import json
 import os
 import shutil
 import sys
+import boto3
+from botocore.exceptions import ClientError
 from datetime import datetime, timedelta
 from pyhocon import ConfigFactory
 
@@ -47,13 +49,39 @@ def fold(fdict, ffmt):
         fkey = fkey.strip('"')    # complex keys may be in quotes
         if fval is True:
             folded += ffmt[0] + fkey
-        elif not (fval is None or fval is False):
+        elif fval not in [None, False]:
             folded += ffmt.format(fkey, fval)
     return folded[1:]
 
 
+# list of AWS regions, and whether they're enabled
+all_regions = {}
+AWS = boto3.session.Session()
+sys.stderr.write("\n>>> Determining region availability...")
+sys.stderr.flush()
+for region in AWS.get_available_regions('ec2'):
+    ec2 = AWS.client('ec2', region_name=region)
+    try:
+        ec2.describe_regions()
+    except ClientError as e:
+        if e.response['Error']['Code'] == 'AuthFailure':
+            sys.stderr.write('-')
+            sys.stderr.flush()
+            all_regions[region] = False
+            continue
+        elif e.response['Error']['Code'] == 'UnauthorizedOperation':
+            # have access to the region, but not to ec2:DescribeRegions
+            pass
+        else:
+            raise
+    sys.stderr.write('+')
+    sys.stderr.flush()
+    all_regions[region] = True
+sys.stderr.write("\n")
+
 # parse/resolve HOCON profile's builds' config
 for build, cfg in BUILDS.items():
+    sys.stderr.write(f">>> Resolving configuration for '{build}'\n")
     build_dir = os.path.join(PROFILE_DIR, build)
 
     # make a fresh profile build directory
@@ -75,6 +103,22 @@ for build, cfg in BUILDS.items():
     if cfg['revision'] == '@NOW@':
         cfg['revision'] = NOW.strftime('%Y%m%d%H%M%S')
 
+    # 'ALL' region expansion (or retraction)
+    if 'ALL' in cfg['ami_regions']:
+        all_val = cfg['ami_regions']['ALL']
+        if all_val not in [None, False]:
+            cfg['ami_regions'] = all_regions
+        else:
+            cfg['ami_regions'] = {}
+    else:
+        # warn/remove disabled regions
+        for region, enabled in all_regions.items():
+            if enabled is not False or region not in cfg['ami_regions']:
+                continue
+            if cfg['ami_regions'][region] not in [None, False]:
+                sys.stderr.write(f"*** WARNING: skipping disabled region {region}\n")
+                cfg['ami_regions'][region] = False
+
     # fold dict vars to scalars
     for foldkey, foldfmt in FOLD_DICTS.items():
         cfg[foldkey] = fold(cfg[foldkey], foldfmt)
@@ -85,7 +129,7 @@ for build, cfg in BUILDS.items():
         if lvl is True:
             # service in default runlevel
             lvls['default'].append(svc)
-        elif not (lvl is None or lvl is False):
+        elif lvl not in [None, False]:
             # service in specified runlevel (skip svc when false/null)
             if lvl not in lvls.keys():
                 lvls[lvl] = []