LibFlute::FileDeliveryTable Class Reference

A class for parsing and creating FLUTE FDTs (File Delivery Tables). More...

#include <FileDeliveryTable.h>

Classes
struct	FileEntry
	An entry for a file in the FDT. More...

Public Member Functions
	FileDeliveryTable (uint32_t instance_id, FecOti fec_oti)
	Create an empty FDT. More...
	FileDeliveryTable (uint32_t instance_id, char *buffer, size_t len)
	Parse an XML string and create a FDT class from it. More...
virtual	~FileDeliveryTable ()
	Default destructor. More...
uint32_t	instance_id ()
	Get the FDT instance ID. More...
void	set_expires (uint64_t exp)
	Set the expiry value. More...
void	add (const FileEntry &entry)
	Add a file entry. More...
void	remove (uint32_t toi)
	Remove a file entry. More...
std::string	to_string () const
	Serialize the FDT to an XML string. More...
std::vector< FileEntry >	file_entries ()
	Get all current file entries. More...

Detailed Description

A class for parsing and creating FLUTE FDTs (File Delivery Tables).

Definition at line 29 of file FileDeliveryTable.h.

Constructor & Destructor Documentation

FileDeliveryTable() [1/2]

LibFlute::FileDeliveryTable::FileDeliveryTable	(	uint32_t	instance_id,
		FecOti	fec_oti
	)

Create an empty FDT.

Parameters

instance_id	FDT instance ID to set
fec_oti	Global FEC OTI parameters

Definition at line 25 of file FileDeliveryTable.cpp.

  : _instance_id( instance_id )
  , _global_fec_oti( fec_oti )
{
}

FileDeliveryTable() [2/2]

LibFlute::FileDeliveryTable::FileDeliveryTable	(	uint32_t	instance_id,
		char *	buffer,
		size_t	len
	)

Parse an XML string and create a FDT class from it.

Parameters

instance_id	FDT instance ID (from ALC headers)
buffer	String containing the FDT XML
len	Length of the buffer

Definition at line 31 of file FileDeliveryTable.cpp.

  : _instance_id( instance_id )
{
  tinyxml2::XMLDocument doc(true, tinyxml2::COLLAPSE_WHITESPACE);
  doc.Parse(buffer, len);
  auto fdt_instance = doc.FirstChildElement("FDT-Instance");
  _expires = std::stoull(fdt_instance->Attribute("Expires"));
 
  spdlog::debug("Received new FDT with instance ID {}", instance_id);
 
  uint8_t def_fec_encoding_id = 0;
  auto val = fdt_instance->Attribute("FEC-OTI-FEC-Encoding-ID");
  if (val != nullptr) {
    def_fec_encoding_id = strtoul(val, nullptr, 0);
  }
 
  uint32_t def_fec_max_source_block_length = 0;
  val = fdt_instance->Attribute("FEC-OTI-Maximum-Source-Block-Length");
  if (val != nullptr) {
    def_fec_max_source_block_length = strtoul(val, nullptr, 0);
  }
 
  uint32_t def_fec_encoding_symbol_length = 0;
  val = fdt_instance->Attribute("FEC-OTI-Encoding-Symbol-Length");
  if (val != nullptr) {
    def_fec_encoding_symbol_length = strtoul(val, nullptr, 0);
  }
 
  for (auto file = fdt_instance->FirstChildElement("File"); 
      file != nullptr; file = file->NextSiblingElement("File")) {
 
    // required attributes
    auto toi_str = file->Attribute("TOI");
    if (toi_str == nullptr) {
      throw "Missing TOI attribute on File element";
    }
    uint32_t toi = strtoull(toi_str, nullptr, 0);
 
    auto content_location = file->Attribute("Content-Location");
    if (content_location == nullptr) {
      throw "Missing Content-Location attribute on File element";
    }
 
    uint32_t content_length = 0;
    val = file->Attribute("Content-Length");
    if (val != nullptr) {
      content_length = strtoull(val, nullptr, 0);
    }
 
    uint32_t transfer_length = 0;
    val = file->Attribute("Transfer-Length");
    if (val != nullptr) {
      transfer_length = strtoull(val, nullptr, 0);
    }
 
    auto content_md5 = file->Attribute("Content-MD5");
    if (!content_md5) {
      content_md5 = "";
    }
 
    auto content_type = file->Attribute("Content-Type");
    if (!content_type) {
      content_type = "";
    }
 
    auto encoding_id = def_fec_encoding_id;
    val = file->Attribute("FEC-OTI-FEC-Encoding-ID");
    if (val != nullptr) {
      encoding_id = strtoul(val, nullptr, 0);
    }
 
    auto max_source_block_length = def_fec_max_source_block_length;
    val = file->Attribute("FEC-OTI-Maximum-Source-Block-Length");
    if (val != nullptr) {
      max_source_block_length = strtoul(val, nullptr, 0);
    }
 
    auto encoding_symbol_length = def_fec_encoding_symbol_length;
    val = file->Attribute("FEC-OTI-Encoding-Symbol-Length");
    if (val != nullptr) {
      encoding_symbol_length = strtoul(val, nullptr, 0);
    }
    uint32_t expires = 0;
    auto cc = file->FirstChildElement("mbms2007:Cache-Control");
    if (cc) {
      auto expires_elem = cc->FirstChildElement("mbms2007:Expires");
      if (expires_elem) {
        expires = strtoul(expires_elem->GetText(), nullptr, 0);
      }
    }
 
    FecOti fec_oti{
      (FecScheme)encoding_id,
        transfer_length,
        encoding_symbol_length,
        max_source_block_length
    };
 
    FileEntry fe{
      toi,
        std::string(content_location),
        content_length,
        std::string(content_md5),
        std::string(content_type),
        expires,
        fec_oti
    };
    _file_entries.push_back(fe);
  }
}

~FileDeliveryTable()

virtual LibFlute::FileDeliveryTable::~FileDeliveryTable ( )

inlinevirtual

Default destructor.

Definition at line 51 of file FileDeliveryTable.h.

{};

Member Function Documentation

add()

auto LibFlute::FileDeliveryTable::add

(

const FileEntry &

entry

)

Add a file entry.

Definition at line 142 of file FileDeliveryTable.cpp.

{
  _instance_id++;
  _file_entries.push_back(fe);
}

file_entries()

std::vector<FileEntry> LibFlute::FileDeliveryTable::file_entries ( )

inline

Get all current file entries.

Definition at line 94 of file FileDeliveryTable.h.

{ return _file_entries; };

instance_id()

uint32_t LibFlute::FileDeliveryTable::instance_id ( )

inline

Get the FDT instance ID.

Definition at line 56 of file FileDeliveryTable.h.

{ return _instance_id; };

remove()

auto LibFlute::FileDeliveryTable::remove

(

uint32_t

toi

)

Remove a file entry.

Definition at line 148 of file FileDeliveryTable.cpp.

{
  for (auto it = _file_entries.cbegin(); it != _file_entries.cend();) {
    if (it->toi == toi) {
      it = _file_entries.erase(it);
    } else {
      ++it;
    }
  }
  _instance_id++;
}

set_expires()

void LibFlute::FileDeliveryTable::set_expires ( uint64_t  exp )

inline

Set the expiry value.

Definition at line 74 of file FileDeliveryTable.h.

{ _expires = exp; };

to_string()

auto LibFlute::FileDeliveryTable::to_string

(

)

const

Serialize the FDT to an XML string.

Definition at line 160 of file FileDeliveryTable.cpp.

                                                             {
  tinyxml2::XMLDocument doc;
  doc.InsertFirstChild( doc.NewDeclaration() );
  auto root = doc.NewElement("FDT-Instance");
  root->SetAttribute("Expires", std::to_string(_expires).c_str());
  root->SetAttribute("FEC-OTI-FEC-Encoding-ID", (unsigned)_global_fec_oti.encoding_id);
  root->SetAttribute("FEC-OTI-Maximum-Source-Block-Length", (unsigned)_global_fec_oti.max_source_block_length);
  root->SetAttribute("FEC-OTI-Encoding-Symbol-Length", (unsigned)_global_fec_oti.encoding_symbol_length);
  root->SetAttribute("xmlns:mbms2007", "urn:3GPP:metadata:2007:MBMS:FLUTE:FDT");
  doc.InsertEndChild(root);
 
  for (const auto& file : _file_entries) {
    auto f = doc.NewElement("File");
    f->SetAttribute("TOI", file.toi);
    f->SetAttribute("Content-Location", file.content_location.c_str());
    f->SetAttribute("Content-Length", file.content_length);
    f->SetAttribute("Transfer-Length", (unsigned)file.fec_oti.transfer_length);
    f->SetAttribute("Content-MD5", file.content_md5.c_str());
    f->SetAttribute("Content-Type", file.content_type.c_str());
    auto cc = doc.NewElement("mbms2007:Cache-Control");
    auto exp = doc.NewElement("mbms2007:Expires");
    exp->SetText(std::to_string(file.expires).c_str());
    cc->InsertEndChild(exp);
    f->InsertEndChild(cc);
    root->InsertEndChild(f);
  }
 
 
  tinyxml2::XMLPrinter printer;
  doc.Print(&printer);
  return std::string(printer.CStr());
}

---

The documentation for this class was generated from the following files:

• include/FileDeliveryTable.h
• src/FileDeliveryTable.cpp