diff options
author | Milo Yip <miloyip@gmail.com> | 2016-04-23 11:02:40 +0300 |
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committer | Milo Yip <miloyip@gmail.com> | 2016-04-23 11:02:40 +0300 |
commit | 05b2ed7532bcaa17f0e2794a7fab67155d3e5cd3 (patch) | |
tree | 16a1f89bb79eb0a926147fd1f6f7846d3ca725ce /example | |
parent | 96ca84798fd546b0d1a22e24c5efde666a6c36c1 (diff) |
Add filterkey and filterkeydom examples
Diffstat (limited to 'example')
-rw-r--r-- | example/CMakeLists.txt | 2 | ||||
-rw-r--r-- | example/filterkey/filterkey.cpp | 130 | ||||
-rw-r--r-- | example/filterkeydom/filterkeydom.cpp | 161 |
3 files changed, 293 insertions, 0 deletions
diff --git a/example/CMakeLists.txt b/example/CMakeLists.txt index fd0e6eb5..4d448ccc 100644 --- a/example/CMakeLists.txt +++ b/example/CMakeLists.txt @@ -7,6 +7,8 @@ endif() set(EXAMPLES capitalize condense + filterkey + filterkeydom jsonx messagereader parsebyparts diff --git a/example/filterkey/filterkey.cpp b/example/filterkey/filterkey.cpp new file mode 100644 index 00000000..14163625 --- /dev/null +++ b/example/filterkey/filterkey.cpp @@ -0,0 +1,130 @@ +// JSON filterkey example with SAX-style API. + +// This example parses JSON text from stdin with validation. +// During parsing, specified key will be filtered using a SAX handler. +// It re-output the JSON content to stdout without whitespace. + +#include "rapidjson/reader.h" +#include "rapidjson/writer.h" +#include "rapidjson/filereadstream.h" +#include "rapidjson/filewritestream.h" +#include "rapidjson/error/en.h" +#include <stack> + +using namespace rapidjson; + +// This handler forwards event into an output handler, with filtering the descendent events of specified key. +template <typename OutputHandler> +struct FilterKeyHandler { + typedef char Ch; + + FilterKeyHandler(OutputHandler& outputHandler, const Ch* keyString, SizeType keyLength) : + outputHandler_(outputHandler), keyString_(keyString), keyLength_(keyLength), filterValueDepth_(), filteredKeyCount_() + {} + + bool Null() { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Null() && EndValue(); } + bool Bool(bool b) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Bool(b) && EndValue(); } + bool Int(int i) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Int(i) && EndValue(); } + bool Uint(unsigned u) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Uint(u) && EndValue(); } + bool Int64(int64_t i) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Int64(i) && EndValue(); } + bool Uint64(uint64_t u) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Uint64(u) && EndValue(); } + bool Double(double d) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Double(d) && EndValue(); } + bool RawNumber(const Ch* str, SizeType len, bool copy) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.RawNumber(str, len, copy) && EndValue(); } + bool String (const Ch* str, SizeType len, bool copy) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.String (str, len, copy) && EndValue(); } + + bool StartObject() { + if (filterValueDepth_ > 0) { + filterValueDepth_++; + return true; + } + else { + filteredKeyCount_.push(0); + return outputHandler_.StartObject(); + } + } + + bool Key(const Ch* str, SizeType len, bool copy) { + if (filterValueDepth_ > 0) + return true; + else if (len == keyLength_ && std::memcmp(str, keyString_, len) == 0) { + filterValueDepth_ = 1; + return true; + } + else { + ++filteredKeyCount_.top(); + return outputHandler_.Key(str, len, copy); + } + } + + bool EndObject(SizeType) { + if (filterValueDepth_ > 0) { + filterValueDepth_--; + return EndValue(); + } + else { + // Use our own filtered memberCount + SizeType memberCount = filteredKeyCount_.top(); + filteredKeyCount_.pop(); + return outputHandler_.EndObject(memberCount) && EndValue(); + } + } + + bool StartArray() { + if (filterValueDepth_ > 0) { + filterValueDepth_++; + return true; + } + else + return outputHandler_.StartArray(); + } + + bool EndArray(SizeType elementCount) { + if (filterValueDepth_ > 0) { + filterValueDepth_--; + return EndValue(); + } + else + return outputHandler_.EndArray(elementCount) && EndValue(); + } + + bool EndValue() { + if (filterValueDepth_ == 1) // Just at the end of value after filtered key + filterValueDepth_ = 0; + return true; + } + + OutputHandler& outputHandler_; + const char* keyString_; + const SizeType keyLength_; + unsigned filterValueDepth_; + std::stack<SizeType> filteredKeyCount_; +}; + +int main(int argc, char* argv[]) { + if (argc != 2) { + fprintf(stderr, "filterkey key < input.json > output.json\n"); + return 1; + } + + // Prepare JSON reader and input stream. + Reader reader; + char readBuffer[65536]; + FileReadStream is(stdin, readBuffer, sizeof(readBuffer)); + + // Prepare JSON writer and output stream. + char writeBuffer[65536]; + FileWriteStream os(stdout, writeBuffer, sizeof(writeBuffer)); + Writer<FileWriteStream> writer(os); + + // Prepare Filter + FilterKeyHandler<Writer<FileWriteStream> > filter(writer, argv[1], static_cast<SizeType>(strlen(argv[1]))); + + // JSON reader parse from the input stream, filter handler filters the events, and forward to writer. + // i.e. the events flow is: reader -> filter -> writer + if (!reader.Parse(is, filter)) { + fprintf(stderr, "\nError(%u): %s\n", static_cast<unsigned>(reader.GetErrorOffset()), GetParseError_En(reader.GetParseErrorCode())); + return 1; + } + + return 0; +} diff --git a/example/filterkeydom/filterkeydom.cpp b/example/filterkeydom/filterkeydom.cpp new file mode 100644 index 00000000..aba50bd0 --- /dev/null +++ b/example/filterkeydom/filterkeydom.cpp @@ -0,0 +1,161 @@ +// JSON filterkey example which populates filtered SAX events into a Document. + +// This example parses JSON text from stdin with validation. +// During parsing, specified key will be filtered using a SAX handler. +// And finally the filtered events are used to populate a Document. +// As an example, the document is written to standard output. + +#include "rapidjson/document.h" +#include "rapidjson/writer.h" +#include "rapidjson/filereadstream.h" +#include "rapidjson/filewritestream.h" +#include "rapidjson/error/en.h" +#include <stack> + +using namespace rapidjson; + +// This handler forwards event into an output handler, with filtering the descendent events of specified key. +template <typename OutputHandler> +struct FilterKeyHandler { + typedef char Ch; + + FilterKeyHandler(OutputHandler& outputHandler, const Ch* keyString, SizeType keyLength) : + outputHandler_(outputHandler), keyString_(keyString), keyLength_(keyLength), filterValueDepth_(), filteredKeyCount_() + {} + + bool Null() { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Null() && EndValue(); } + bool Bool(bool b) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Bool(b) && EndValue(); } + bool Int(int i) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Int(i) && EndValue(); } + bool Uint(unsigned u) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Uint(u) && EndValue(); } + bool Int64(int64_t i) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Int64(i) && EndValue(); } + bool Uint64(uint64_t u) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Uint64(u) && EndValue(); } + bool Double(double d) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.Double(d) && EndValue(); } + bool RawNumber(const Ch* str, SizeType len, bool copy) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.RawNumber(str, len, copy) && EndValue(); } + bool String (const Ch* str, SizeType len, bool copy) { return filterValueDepth_ > 0 ? EndValue() : outputHandler_.String (str, len, copy) && EndValue(); } + + bool StartObject() { + if (filterValueDepth_ > 0) { + filterValueDepth_++; + return true; + } + else { + filteredKeyCount_.push(0); + return outputHandler_.StartObject(); + } + } + + bool Key(const Ch* str, SizeType len, bool copy) { + if (filterValueDepth_ > 0) + return true; + else if (len == keyLength_ && std::memcmp(str, keyString_, len) == 0) { + filterValueDepth_ = 1; + return true; + } + else { + ++filteredKeyCount_.top(); + return outputHandler_.Key(str, len, copy); + } + } + + bool EndObject(SizeType) { + if (filterValueDepth_ > 0) { + filterValueDepth_--; + return EndValue(); + } + else { + // Use our own filtered memberCount + SizeType memberCount = filteredKeyCount_.top(); + filteredKeyCount_.pop(); + return outputHandler_.EndObject(memberCount) && EndValue(); + } + } + + bool StartArray() { + if (filterValueDepth_ > 0) { + filterValueDepth_++; + return true; + } + else + return outputHandler_.StartArray(); + } + + bool EndArray(SizeType elementCount) { + if (filterValueDepth_ > 0) { + filterValueDepth_--; + return EndValue(); + } + else + return outputHandler_.EndArray(elementCount) && EndValue(); + } + + bool EndValue() { + if (filterValueDepth_ == 1) // Just at the end of value after filtered key + filterValueDepth_ = 0; + return true; + } + + OutputHandler& outputHandler_; + const char* keyString_; + const SizeType keyLength_; + unsigned filterValueDepth_; + std::stack<SizeType> filteredKeyCount_; +}; + +// Implements a generator for Document::Populate() +template <typename InputStream> +class FilterKeyReader { +public: + typedef char Ch; + + FilterKeyReader(InputStream& is, const Ch* keyString, SizeType keyLength) : + is_(is), keyString_(keyString), keyLength_(keyLength) + {} + + // SAX event flow: reader -> filter -> handler + template <typename Handler> + bool operator()(Handler& handler) { + FilterKeyHandler<Handler> filter(handler, keyString_, keyLength_); + Reader reader; + return parseResult_ = reader.Parse(is_, filter); + } + + const ParseResult& GetParseResult() const { return parseResult_; } + +private: + InputStream& is_; + const char* keyString_; + const SizeType keyLength_; + ParseResult parseResult_; +}; + +int main(int argc, char* argv[]) { + if (argc != 2) { + fprintf(stderr, "filterkeydom key < input.json > output.json\n"); + return 1; + } + + // Prepare input stream. + char readBuffer[65536]; + FileReadStream is(stdin, readBuffer, sizeof(readBuffer)); + + // Prepare Filter + FilterKeyReader<FileReadStream> reader(is, argv[1], static_cast<SizeType>(strlen(argv[1]))); + + // Populates the filtered events from reader + Document document; + document.Populate(reader); + ParseResult pr = reader.GetParseResult(); + if (!pr) { + fprintf(stderr, "\nError(%u): %s\n", static_cast<unsigned>(pr.Offset()), GetParseError_En(pr.Code())); + return 1; + } + + // Prepare JSON writer and output stream. + char writeBuffer[65536]; + FileWriteStream os(stdout, writeBuffer, sizeof(writeBuffer)); + Writer<FileWriteStream> writer(os); + + // Write the document to standard output + document.Accept(writer); + return 0; +} |