CentralMetadataProvider Class Reference

Class to obtain payload metadata from the central database server via REST requests. More...

#include <CentralMetadataProvider.h>

Inheritance diagram for CentralMetadataProvider:

Collaboration diagram for CentralMetadataProvider:

Public Types
using	PayloadMap = std::unordered_map< std::string, PayloadMetadata >
	Type for the internal list of payloads.

Public Member Functions
	CentralMetadataProvider (std::string baseUrl, const std::set< std::string > &usableTagStates)
	Create using a base rest url to find the server endpoints.
virtual	~CentralMetadataProvider ()=default
	default destructor
std::string	getGlobaltagStatus (const std::string &name) override
	Check the status of a given globaltag . More...
bool	updatePayloads (const std::string &globaltag, int exp, int run) override
	Update the list of known payloads for the given globaltag/exp/run. More...
bool	setTags (const std::vector< std::string > &tags)
	Set the list of globaltag names to be considered for payloads. More...
bool	getPayloads (int exp, int run, std::vector< PayloadMetadata > &info)
	Update the information in the vector of metadata instances with the actual values. More...
std::set< std::string >	getUsableTagStates ()
	Get the valid tag states when checking globaltag status.
void	setUsableTagStates (const std::set< std::string > &states)
	Set the valid tag states for this provider when checking globaltag status. More...

Protected Member Functions
void	addPayload (PayloadMetadata &&payload, const std::string &messagePrefix="")
	Add a payload information to the internal list. More...
void	printInfoMessage (const std::string &provider)
	Print an INFO message about the used metadata provider. More...

Protected Attributes
std::vector< std::string >	m_tags
	List of globaltags to consider.
std::unordered_map< std::string, PayloadMetadataCache >	m_cache
	Map of globaltag->known metadata.
PayloadMap *	m_payloads {nullptr}
	Map of known payloads for current conditions.
std::set< std::string >	m_usableTagStates {"TESTING", "VALIDATED", "RUNNING", "PUBLISHED"}
	Set of global tag states to consider valid (except for 'INVALID' which is always considered invalid)

Private Member Functions
nlohmann::json	get (const std::string &url)
	Downlad a given relative url (the baseUrl will be prependend) and return the json description. More...

Private Attributes
Downloader &	m_downloader {Downloader::getDefaultInstance()}
	Reference to the downloader instance for convenience.
std::string	m_baseUrl
	base url of the server

Detailed Description

Class to obtain payload metadata from the central database server via REST requests.

Definition at line 16 of file CentralMetadataProvider.h.

Member Function Documentation

addPayload()

void addPayload ( PayloadMetadata &&  payload, const std::string &  messagePrefix = ""  )

protectedinherited

Add a payload information to the internal list.

This should be called by implementations during updatePayloads() for each payload found.

Parameters

payload	payload information filled from the globaltag
messagePrefix	a message prefix to be shown for possible log messages to indicate the correct metadata provider

Definition at line 91 of file MetadataProvider.cc.

  {
    const auto [it, inserted] = m_payloads->emplace(payload.name, payload);
    if (!inserted) {
      auto& existing = it->second;
      if (existing.revision < payload.revision) {
        std::swap(existing, payload);
      }
      B2DEBUG(36, messagePrefix << (messagePrefix.empty() ? "" : ": ") << "Found duplicate payload. Discarding one of them"
              << LogVar("globaltag", existing.globaltag)
              << LogVar("name", existing.name)
              << LogVar("revision", existing.revision)
              << LogVar("checksum", existing.checksum)
              << LogVar("discarded revision", payload.revision));
    } else {
      B2DEBUG(37, messagePrefix << (messagePrefix.empty() ? "" : ": ") << "Found payload"
              << LogVar("globaltag", payload.globaltag)
              << LogVar("name", payload.name)
              << LogVar("revision", payload.revision)
              << LogVar("checksum", payload.checksum));
    }
  }

get()

json get ( const std::string &  url )

private

Downlad a given relative url (the baseUrl will be prependend) and return the json description.

Will raise exceptions on error

Definition at line 40 of file CentralMetadataProvider.cc.

  {
    std::stringstream stream;
    const auto fullUrl = m_downloader.joinWithSlash(m_baseUrl, url);
    m_downloader.download(fullUrl, stream);
    stream.clear();
    stream.seekg(0, std::ios::beg);
    return json::parse(stream);
  }

getGlobaltagStatus()

std::string getGlobaltagStatus ( const std::string &  name )

overridevirtual

Check the status of a given globaltag .

Returns

the status of the globaltag (like "OPEN", "INVALID", "PUBLISHED"). Returns empty string on any errors or if the tag doesn't exist.

Implements MetadataProvider.

Definition at line 50 of file CentralMetadataProvider.cc.

getPayloads()

bool getPayloads ( int  exp, int  run, std::vector< PayloadMetadata > &  info  )

inherited

Update the information in the vector of metadata instances with the actual values.

The input is a list of metadata instances and the metadata provider will try to modify them in place and add all the missing information it can find.

• It will try to find iov, revision, checksum, url for each entry which doesn't have a valid revision number (revision=0)
• It will ignore any entries with a valid revision number (revision>0)
• any payload which cannot be found in any globaltag will raise an error as long as required=true
• the modified list can still contain payloads without a valid revision some payloads could not be found.

This function will call updatePayloads() if necessary to update the list of known payloads for a given run but it will try to cache these results so incrementally asking for new payloads as they get requested is perfectly fine.

updatePayloads() will only called for globaltags if we still need to find payload information. If all payloads are found no further queries will be made so adding additional globaltags that are not used at the end is not expensive.

Parameters

	exp	the experiment number
	run	the run number
[in,out]	info	a list of metadata instances which we try to find the missing metadata for.

Returns

true if all required payloads could be found, false if at least one payload which still didn't have a valid revision number and is required could not be found.

Definition at line 36 of file MetadataProvider.cc.

printInfoMessage()

void printInfoMessage ( const std::string &  provider = "" )

protectedinherited

Print an INFO message about the used metadata provider.

Parameters

provider

the actual metadata provider used for the job

Definition at line 114 of file MetadataProvider.cc.

setTags()

bool setTags ( const std::vector< std::string > &  tags )

inherited

Set the list of globaltag names to be considered for payloads.

This should be called before requesting any payloads but after calling setValidTagStates().

Returns

true if all globaltags can be found and are in a valid state

Definition at line 15 of file MetadataProvider.cc.

setUsableTagStates()

void setUsableTagStates ( const std::set< std::string > &  states )

inlineinherited

Set the valid tag states for this provider when checking globaltag status.

Should be called before setTags() if necessary.

Warning

The state "INVALID" will never be accepted and removed from the given set if present

Definition at line 128 of file MetadataProvider.h.

    {
      m_usableTagStates = states;
      m_usableTagStates.erase("INVALID");
    }

updatePayloads()

bool updatePayloads ( const std::string &  globaltag, int  exp, int  run  )

overridevirtual

Update the list of known payloads for the given globaltag/exp/run.

This basically just calls addPayload() for each payload it finds in the globaltag for the given exp/run.

Returns

true on sucess, false on any error

Implements MetadataProvider.

Definition at line 68 of file CentralMetadataProvider.cc.

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

• framework/database/include/CentralMetadataProvider.h
• framework/database/src/CentralMetadataProvider.cc