waiting for conversion to finish instead and capture exit code

Author: emmmile

lib/jekyll-webp/webpExec.rb

@@ -17,7 +17,7 @@ def self.run(flags, input_file, output_file)
         # What is the OS and architecture specific executable name?
         exe_name = WebpExec.exe_name
 
-        # We need to locate the Gems bin path as we're currently running inside the 
+        # We need to locate the Gems bin path as we're currently running inside the
         # jekyll site working directory
         # http://stackoverflow.com/a/10083594/779521
         gem_spec = Gem::Specification.find_by_name("jekyll-webp")
@@ -27,13 +27,25 @@ def self.run(flags, input_file, output_file)
         full_path = File.join(gem_root, bin_path, exe_name)
 
         # Construct the full program call
-        cmd = "\"#{full_path}\" -quiet -mt \"#{flags}\" \"#{input_file}\" -o \"#{output_file}\""
-        
+        cmd = "\"#{full_path}\" -quiet -mt #{flags} \"#{input_file}\" -o \"#{output_file}\""
+
         # Execute the command
-        stdin, stdout, stderr = Open3.popen3(cmd)
+        exit_code = 0
+        error = ""
+        output = ""
+        Open3.popen3(cmd) do |stdin, stdout, stderr, wait_thr|
+          stdin.close # wo don't pass any input to the process
+          output = stdout.gets
+          error = stderr.gets
+          exit_code = wait_thr.value
+        end
+
+        if exit_code != 0
+          Jekyll.logger.error("WebP:","cwebp returned #{exit_code} with error #{error}")
+        end
 
         # Return any captured return value
-        return [stdin, stdout, stderr]
+        return [output, error]
       end #function run
 
       #
@@ -60,7 +72,7 @@ def self.exe_name
       end #function exe_name
 
     end #class WebpExec
-    
+
   end #module Webp
 
   module OS