QPDFJob: partial mode for initializeFromJson

3 files changed, 26 insertions, 7 deletions

diff --git a/include/qpdf/QPDFJob.hh b/include/qpdf/QPDFJob.hh
index 5178c4c1..77ef6068 100644
--- a/include/qpdf/QPDFJob.hh
+++ b/include/qpdf/QPDFJob.hh
@@ -73,8 +73,20 @@ class QPDFJob
     void initializeFromArgv(int argc, char* argv[],
                             char const* progname_env = nullptr);
 
+    // Initialize a QPDFJob from json. Passing partial = true prevents
+    // this method from doing the final checks (calling
+    // checkConfiguration) after processing the json file. This makes
+    // it possible to initialze QPDFJob in stages using multiple json
+    // files or to have a json file that can be processed from the CLI
+    // with --job-json-file and be combined with other arguments. For
+    // example, you might include only encryption parameters, leaving
+    // it up to the rest of the command-line arguments to provide
+    // input and output files. initializeFromJson is called with
+    // partial = true when invoked from the command line. To make sure
+    // that the json file is fully valid on its own, just don't
+    // specify any other command-line flags.
     QPDF_DLL
-    void initializeFromJson(std::string const& json);
+    void initializeFromJson(std::string const& json, bool partial = false);
 
     // Set name that is used to prefix verbose messages, progress
     // messages, and other things that the library writes to output
diff --git a/libqpdf/QPDFJob_config.cc b/libqpdf/QPDFJob_config.cc
index bf33820a..02f1b69e 100644
--- a/libqpdf/QPDFJob_config.cc
+++ b/libqpdf/QPDFJob_config.cc
@@ -730,7 +730,7 @@ QPDFJob::Config::jobJsonFile(char const* parameter)
     QUtil::read_file_into_memory(parameter, file_buf, size);
     try
     {
-        o.initializeFromJson(std::string(file_buf.getPointer(), size));
+        o.initializeFromJson(std::string(file_buf.getPointer(), size), true);
     }
     catch (std::exception& e)
     {
diff --git a/libqpdf/QPDFJob_json.cc b/libqpdf/QPDFJob_json.cc
index 02e851b0..6525b761 100644
--- a/libqpdf/QPDFJob_json.cc
+++ b/libqpdf/QPDFJob_json.cc
@@ -15,7 +15,7 @@ namespace
     class Handlers
     {
       public:
-        Handlers(std::shared_ptr<QPDFJob::Config> c_main);
+        Handlers(bool partial, std::shared_ptr<QPDFJob::Config> c_main);
         void handle(JSON&);
 
       private:
@@ -47,6 +47,7 @@ namespace
         setup_handler_t bindSetup(void (Handlers::*f)(std::string const&));
 
         std::list<std::shared_ptr<JSONHandler>> json_handlers;
+        bool partial;
         JSONHandler* jh; // points to last of json_handlers
         std::shared_ptr<QPDFJob::Config> c_main;
         std::shared_ptr<QPDFJob::CopyAttConfig> c_copy_att;
@@ -57,7 +58,8 @@ namespace
     };
 }
 
-Handlers::Handlers(std::shared_ptr<QPDFJob::Config> c_main) :
+Handlers::Handlers(bool partial, std::shared_ptr<QPDFJob::Config> c_main) :
+    partial(partial),
     jh(nullptr),
     c_main(c_main)
 {
@@ -95,7 +97,12 @@ Handlers::initHandlers()
     this->jh = this->json_handlers.back().get();
     jh->addDictHandlers(
         [](std::string const&, JSON){},
-        [this](std::string const&){c_main->checkConfiguration();});
+        [this](std::string const&){
+            if (! this->partial)
+            {
+                c_main->checkConfiguration();
+            }
+        });
 
 #   include <qpdf/auto_job_json_init.hh>
 
@@ -623,7 +630,7 @@ Handlers::setupOptionsUnderlayPassword(std::string const& key)
 }
 
 void
-QPDFJob::initializeFromJson(std::string const& json)
+QPDFJob::initializeFromJson(std::string const& json, bool partial)
 {
     std::list<std::string> errors;
     JSON j = JSON::parse(json);
@@ -639,5 +646,5 @@ QPDFJob::initializeFromJson(std::string const& json)
         throw std::runtime_error(msg.str());
     }
 
-    Handlers(config()).handle(j);
+    Handlers(partial, config()).handle(j);
 }