Fix options bug; add ability to skip missing migrate sources (#60)

Fix options bug; add ability to skip missing migrate sources

The `options:` setting for `migrate` actions was reading an erroneous truthiness to test for the existence of a setting. Fixed this so opt settings other than `inclusive: false` actually work.

Added the ability to set an option `missing:` with either `warn`, `skip`, or `exit` as values.
If `missing: warn`, the operation skips the migrate step and logs a warning to console.
If `missing: exit` (the default, w/ backward compatibility) the operation throws an error and exits.

Added example and explanation for new `missing:` setting to README.

* Remove erroneous require (from testing)

* Rearrange missing handling; add 'skip' option

* Bump version to 0.9.5

README.adoc

@@ -554,14 +554,19 @@ In addition to designating `action: migrate`, migrate operations require just a
 [source,yaml]
 .Example config -- Instructing file copies with 'migrate' action
 ----
+- action: migrate
+  source: index.adoc
+  target: _build/
 - action: migrate
   source: assets/images
   target: _build/img
   options:
     inclusive: false
 - action: migrate
-  source: index-map.adoc
-  target: _build/index-map.adoc
+  source: tmp/{{imported_file}}.adoc
+  target: _build/{{portal_path}}/{{imported_file}}.adoc
+  options:
+    missing: warn
 ----
 
 The first action step above copies all the files and folders in `assets/images` and adds them to `_build/img`.
@@ -570,6 +575,11 @@ When both the source and target paths are directories and inclusive is `true`, t
 When inclusive is `false`, they copy to `target/`.
 
 Individual files must be listed in individual steps, one per step, as in the second step above.
+
+In case of a missing source directory or file to be migrated, the default behavior is to exit the build operation (`missing: exit`).
+This can be overridden and the migrate action skipped when the source is missing.
+Setting the option `missing: warn` logs a warning to console, and `missing: skip` will only print a warning under `--verbose` operations.
+
 // end::migrate-operations[]
 
 === Render Operations

lib/liquidoc.rb

@@ -123,8 +123,12 @@ def iterate_build cfg
       end
     when "migrate"
       inclusive = true
-      inclusive = step.options['inclusive'] if defined?(step.options['inclusive'])
-      copy_assets(step.source, step.target, inclusive)
+      missing = "exit"
+      if step.options
+        inclusive = step.options['inclusive'] if step.options.has_key?("inclusive")
+        missing = step.options['missing'] if step.options.has_key?("missing")
+      end
+      copy_assets(step.source, step.target, inclusive, missing)
     when "render"
       validate_file_input(step.source, "source") if step.source
       builds = step.builds
@@ -252,6 +256,7 @@ def initialize step
     if (defined?(@step['action'])).nil?
       raise "ConfigStructError"
     end
+    @step['options'] = nil unless defined?(step['options'])
     validate()
   end
 
@@ -787,11 +792,25 @@ def regurgidata datasrc, output
 # ===
 
 # Copy images and other files into target dir
-def copy_assets src, dest, inclusive=true
+def copy_assets src, dest, inclusive=true, missing='exit'
   unless File.file?(src)
     unless inclusive then src = src + "/." end
   end
-  @logger.debug "Copying #{src} to #{dest}"
+  src_to_dest = "#{src} to #{dest}"
+  unless (File.file?(src) || File.directory?(src))
+    case missing
+    when "warn"
+      @logger.warn "Skipping migrate action (#{src_to_dest}); source not found."
+      return
+    when "skip"
+      @logger.debug "Skipping migrate action (#{src_to_dest}); source not found."
+      return
+    when "exit"
+      @logger.error "Unexpected missing source in migrate action (#{src_to_dest})."
+      raise "MissingSourceExit"
+    end
+  end
+  @logger.debug "Copying #{src_to_dest}"
   begin
     FileUtils.mkdir_p(dest) unless File.directory?(dest)
     if File.directory?(src)
@@ -801,7 +820,7 @@ def copy_assets src, dest, inclusive=true
     end
     @logger.info "Copied #{src} to #{dest}."
   rescue Exception => ex
-    @logger.warn "Problem while copying assets. #{ex.message}"
+    @logger.error "Problem while copying assets. #{ex.message}"
     raise
   end
 end
@@ -905,6 +924,9 @@ def asciidocify doc, build
   if build.backend == "pdf"
     @logger.info "Generating PDF. This can take some time..."
   end
+
+
+
   Asciidoctor.convert_file(
     doc.index,
     to_file: to_file,

lib/liquidoc/version.rb

@@ -1,3 +1,3 @@
 module Liquidoc
-  VERSION = "0.9.4"
+  VERSION = "0.9.5"
 end