support decoding json from abstract input in API

2 files changed, 16 insertions, 9 deletions

diff --git a/vespalib/src/vespa/vespalib/data/slime/json_format.cpp b/vespalib/src/vespa/vespalib/data/slime/json_format.cpp
index e8ebcfb9e10..30ac5d98042 100644
--- a/vespalib/src/vespa/vespalib/data/slime/json_format.cpp
+++ b/vespalib/src/vespa/vespalib/data/slime/json_format.cpp
@@ -178,7 +178,7 @@ struct JsonDecoder {
     vespalib::string key;
     vespalib::string value;
 
-    JsonDecoder(InputReader &input) : in(input), c(in.read()), key(), value() {}
+    JsonDecoder(InputReader &reader) : in(reader), c(in.read()), key(), value() {}
 
     void next() {
         if (in.obtain() > 0) {
@@ -484,18 +484,24 @@ JsonFormat::encode(const Slime &slime, Output &output, bool compact)
 }
 
 size_t
-JsonFormat::decode(const Memory &memory, Slime &slime)
+JsonFormat::decode(Input &input, Slime &slime)
 {
-    MemoryInput memory_input(memory);
-    InputReader input(memory_input);
-    JsonDecoder decoder(input);
+    InputReader reader(input);
+    JsonDecoder decoder(reader);
     decoder.decodeValue(slime);
-    if (input.failed()) {
+    if (reader.failed()) {
         slime.wrap("partial_result");
-        slime.get().setLong("offending_offset", input.get_offset());
-        slime.get().setString("error_message", input.get_error_message());
+        slime.get().setLong("offending_offset", reader.get_offset());
+        slime.get().setString("error_message", reader.get_error_message());
     }
-    return input.failed() ? 0 : input.get_offset();
+    return reader.failed() ? 0 : reader.get_offset();
+}
+
+size_t
+JsonFormat::decode(const Memory &memory, Slime &slime)
+{
+    MemoryInput input(memory);
+    return decode(input, slime);
 }
 
 } // namespace vespalib::slime
diff --git a/vespalib/src/vespa/vespalib/data/slime/json_format.h b/vespalib/src/vespa/vespalib/data/slime/json_format.h
index e334cd55546..3d998e5bcd4 100644
--- a/vespalib/src/vespa/vespalib/data/slime/json_format.h
+++ b/vespalib/src/vespa/vespalib/data/slime/json_format.h
@@ -18,6 +18,7 @@ class Inspector;
 struct JsonFormat {
     static void encode(const Inspector &inspector, Output &output, bool compact);
     static void encode(const Slime &slime, Output &output, bool compact);
+    static size_t decode(Input &input, Slime &slime);
     static size_t decode(const Memory &memory, Slime &slime);
 };