Source code for flowcraft.generator.process

import os
import jinja2
import logging

from os.path import dirname, join, abspath

try:
    import generator.error_handling as eh
except ImportError:
    import flowcraft.generator.error_handling as eh

logger = logging.getLogger("main.{}".format(__name__))


[docs]class Process: """Main interface for basic process functionality The ``Process`` class is intended to be inherited by specific process classes (e.g., :py:class:`IntegrityCoverage`) and provides the basic functionality to build the channels and links between processes. Child classes are expected to inherit the ``__init__`` execution, which basically means that at least, the child must be defined as:: class ChildProcess(Process): def__init__(self, **kwargs): super().__init__(**kwargs) This ensures that when the ``ChildProcess`` class is instantiated, it automatically sets the attributes of the parent class. This also means that child processes must be instantiated providing information on the process type and jinja2 template with the nextflow code. Parameters ---------- template : str Name of the jinja2 template with the nextflow code for that process. Templates are stored in ``generator/templates``. """ RAW_MAPPING = { "fastq": { "params": "fastq", "description": "Path expression to paired-end fastq files." " (default: $params.fastq)", "default_value": "'fastq/*_{1,2}.*'", "channel": "IN_fastq_raw", "channel_str": "Channel.fromFilePairs(params.{0})" ".ifEmpty {{ exit 1, \"No fastq files provided with pattern:" "'${{params.{0}}}'\" }}", "checks": "if (params.{0} instanceof Boolean){{" "exit 1, \"'{0}' must be a path pattern. Provide value:" "'$params.{0}'\"}}\n" "if (!params.{0}){{ exit 1, \"'{0}' parameter " "missing\"}}" }, "fasta": { "params": "fasta", "description": "Path fasta files. (default: $params.fastq)", "default_value": "'fasta/*.fasta'", "channel": "IN_fasta_raw", "channel_str": "Channel.fromPath(params.{0})." "map{{ it -> file(it).exists() ? [it.toString()" ".tokenize('/').last()" ".tokenize('.')[0..-2].join('.'), it] : null }}" ".ifEmpty {{ exit 1, \"No fasta files provided with pattern:" "'${{params.{0}}}'\" }}", "checks": "if (params.{0} instanceof Boolean){{" "exit 1, \"'{0}' must be a path pattern. Provide value:" "'$params.{0}'\"}}\n" "if (!params.{0}){{ exit 1, \"'{0}' parameter " "missing\"}}" }, "accessions": { "params": "accessions", "description": "Path file with accessions, one perline. (" "default: $params.fastq)", "default_value": "null", "channel": "IN_accessions_raw", "channel_str": "Channel.fromPath(params.{0})" ".ifEmpty {{ exit 1, \"No accessions file provided with path:" "'${{params.{0}}}'\" }}", "checks": "if (!params.{0}){{ exit 1, \"'{0}' parameter " "missing\" }}\n" } } """ dict: Contains the mapping between the :attr:`Process.input_type` attribute and the corresponding nextflow parameter and main channel definition, e.g.:: "fastq" : { "params": "fastq", "channel: "<channel> } """ def __init__(self, template): self.pid = None """ int: Process ID number that represents the order and position in the generated pipeline """ self.template = template """ str: Template name for the current process. This string will be used to fetch the file containing the corresponding jinja2 template in the :py:func:`_set_template` method """ self._template_path = None """ str: Path to the file containing the jinja2 template file. It's set in :py:func:`_set_template`. """ self._set_template(template) self.input_type = None """ str: Type of expected input data. Used to verify the connection between two processes is viable. """ self.output_type = None """ str: Type of output data. Used to verify the connection between two processes is viable. """ self.ignore_type = False """ boolean: If True, this process will ignore the input/output type requirements. This attribute is set to True for terminal singleton forks in the pipeline. """ self.ignore_pid = False """ boolean: If True, this process will not make the pid advance. This is used for terminal forks before the end of the pipeline. """ self.dependencies = [] """ list: Contains the dependencies of the current process in the form of the :py:attr:`Process.template` attribute (e.g., [``fastqc``]) """ self.lane = None self.parent_lane = None self.input_channel = None """ str: Place holder of the main input channel for the current process. This attribute can change dynamically depending on the forks and secondary channels in the final pipeline. """ self.output_channel = None """ str: Place holder of the main output channel for the current process. This attribute can change dynamically depending on the forks and secondary channels in the final pipeline. """ self.input_user_channel = None """ dict: Stores a dictionary of two key:value pairs containing the raw input channel for the process. This is automatically determined by the :attr:`~Process.input_type` attribute, and will fetch the information that is mapped in the :attr:`RAW_MAPPING` variable. It will only be used by the first process(es) defined in a pipeline. """ self.link_start = [] """ list: List of strings with the starting points for secondary channels. When building the pipeline, these strings will be matched with equal strings in the :py:attr:`link_end` attribute of other Processes. """ self.link_end = [] """ list: List of dictionaries containing the a string of the ending point for a secondary channel. Each dictionary should contain at least two key/vals: ``{"link": <link string>, "alias":<string for template>}`` """ self.status_channels = ["STATUS_{}".format(template)] """ list: Name of the status channels produced by the process. By default, it sets a single status channel. If more than one status channels are required for the process, list each one in this attribute (e.g., :py:attr:`FastQC.status_channels`) """ self.status_strs = [] """ str: Name of the status channel for the current process. These strings will be provided to the StatusCompiler process to collect and compile status reports """ self.forks = [] """ list: List of strings with the literal definition of the forks for the current process, ready to be added to the template string. """ self.main_forks = [] """ list: List of the channels onto which the main output should be forked into. They will be automatically added to the :attr:`~Process.main_forks` attribute when setting the secondary channels """ self.secondary_inputs = [] """ list: List of dictionaries with secondary input channels from nextflow parameters. This dictionary should contain two key:value pairs with the ``params`` key, containing the parameter name, and the ``channel`` key, containing the nextflow channel definition:: { "params": "pathoSpecies", "channel": "IN_pathoSpecies = Channel .value(params.pathoSpecies)" } """ self.secondary_input_str = "" self.extra_input = "" """ str: with the name of the params that will be used to provide extra input into the process. This extra input will be mixed with the main input channel using nextflow's ``mix`` operator. Its channel will be defined at the start of the pipeline, based on the ``channel_str`` key of the :attr:`~Process.RAW_MAPPING` for the corresponding input type. """ self.params = {} """ dict: Maps the parameter names to the corresponding default values. """ self.param_id = "" """ str: The parameter id suffix that will be added to each parameter. In case it is empty, the multiple identical parameters in different components will be merged. """ self._context = {} """ dict: Dictionary with the keyword placeholders for the string template of the current process. """ self.directives = { self.template: {} } """ dict: Specifies the directives (cpus, memory, container) for each nextflow process in the template. If specified, this directives will be added to the nextflow configuration file. Otherwise, the default values for cpus and memory will be used. In the case of containers, they will not run inside any container. The current supported directives are: - cpus - memory - container - container tag/version An example of directives for two process is as follows:: self.directives = { "processA": {"cpus": 1, "memory": "1GB"}, "processB": {"memory": "5GB", "container": "my/image", "version": "0.5.0"} } """ self.compiler = {} """ dict: Specifies channels from the current process that are received by a compiler process. Each key in this dictionary should match a compiler process key in :attr:`~flowcraft.generator.engine.NextflowGenerator.compilers`. The value should be a list of the channels that will be fed to the compiler process:: self.compiler["patlas_consensus"] = ["mashScreenOutputChannel"] """ def _set_template(self, template): """Sets the path to the appropriate jinja template file When a Process instance is initialized, this method will fetch the location of the appropriate template file, based on the ``template`` argument. It will raise an exception is the template file is not found. Otherwise, it will set the :py:attr:`Process.template_path` attribute. """ # Set template directory tpl_dir = join(dirname(abspath(__file__)), "templates") # Set template file path tpl_path = join(tpl_dir, template + ".nf") if not os.path.exists(tpl_path): raise eh.ProcessError( "Template {} does not exist".format(tpl_path)) self._template_path = join(tpl_dir, template + ".nf")
[docs] def set_main_channel_names(self, input_suffix, output_suffix, lane): """Sets the main channel names based on the provide input and output channel suffixes. This is performed when connecting processes. Parameters ---------- input_suffix : str Suffix added to the input channel. Should be based on the lane and an arbitrary unique id output_suffix : str Suffix added to the output channel. Should be based on the lane and an arbitrary unique id lane : int Sets the lane of the process. """ self.input_channel = "{}_in_{}".format(self.template, input_suffix) self.output_channel = "{}_out_{}".format(self.template, output_suffix) self.lane = lane
[docs] def set_param_id(self, param_id): """Sets the param_id for the process, which will be used to render the template. Parameters ---------- param_id : str The :attr:`param_id` attribute of the process. """ self._context = {**self._context, "param_id": param_id}
[docs] def get_user_channel(self, input_channel, input_type=None): """Returns the main raw channel for the process Provided with at least a channel name, this method returns the raw channel name and specification (the nextflow string definition) for the process. By default, it will fork from the raw input of the process' :attr:`~Process.input_type` attribute. However, this behaviour can be overridden by providing the ``input_type`` argument. If the specified or inferred input type exists in the :attr:`~Process.RAW_MAPPING` dictionary, the channel info dictionary will be retrieved along with the specified input channel. Otherwise, it will return None. An example of the returned dictionary is:: {"input_channel": "myChannel", "params": "fastq", "channel": "IN_fastq_raw", "channel_str":"IN_fastq_raw = Channel.fromFilePairs(params.fastq)" } Returns ------- dict or None Dictionary with the complete raw channel info. None if no channel is found. """ res = {"input_channel": input_channel} itype = input_type if input_type else self.input_type if itype in self.RAW_MAPPING: channel_info = self.RAW_MAPPING[itype] return {**res, **channel_info}
[docs] @staticmethod def render(template, context): """Wrapper to the jinja2 render method from a template file Parameters ---------- template : str Path to template file. context : dict Dictionary with kwargs context to populate the template """ path, filename = os.path.split(template) return jinja2.Environment( loader=jinja2.FileSystemLoader(path or './') ).get_template(filename).render(context)
@property def template_str(self): """Class property that returns a populated template string This property allows the template of a particular process to be dynamically generated and returned when doing ``Process.template_str``. Returns ------- x : str String with the complete and populated process template """ if not self._context: raise eh.ProcessError("Channels must be setup first using the " "set_channels method") logger.debug("Setting context for template {}: {}".format( self.template, self._context )) x = self.render(self._template_path, self._context) return x
[docs] def set_channels(self, **kwargs): """ General purpose method that sets the main channels This method will take a variable number of keyword arguments to set the :py:attr:`Process._context` attribute with the information on the main channels for the process. This is done by appending the process ID (:py:attr:`Process.pid`) attribute to the input, output and status channel prefix strings. In the output channel, the process ID is incremented by 1 to allow the connection with the channel in the next process. The ``**kwargs`` system for setting the :py:attr:`Process._context` attribute also provides additional flexibility. In this way, individual processes can provide additional information not covered in this method, without changing it. Parameters ---------- kwargs : dict Dictionary with the keyword arguments for setting up the template context """ if not self.pid: self.pid = "{}_{}".format(self.lane, kwargs.get("pid")) for i in self.status_channels: if i.startswith("STATUS_"): self.status_strs.append("{}_{}".format(i, self.pid)) else: self.status_strs.append("STATUS_{}_{}".format(i, self.pid)) if self.main_forks: logger.debug("Setting main fork channels: {}".format( self.main_forks)) operator = "set" if len(self.main_forks) == 1 else "into" self.forks = ["\n{}.{}{{ {} }}\n".format( self.output_channel, operator, ";".join(self.main_forks))] self._context = {**kwargs, **{"input_channel": self.input_channel, "output_channel": self.output_channel, "template": self.template, "forks": "\n".join(self.forks), "pid": self.pid}}
[docs] def update_main_input(self, input_str): self.input_channel = input_str self._context["input_channel"] = self.input_channel
[docs] def update_main_forks(self, sink): """Updates the forks attribute with the sink channel destination Parameters ---------- sink : str Channel onto which the main input will be forked to """ if not self.main_forks: self.main_forks = [self.output_channel] self.output_channel = "_{}".format(self.output_channel) self.main_forks.append(sink) # fork_lst = self.forks + self.main_forks operator = "set" if len(self.main_forks) == 1 else "into" self.forks = ["\n{}.{}{{ {} }}\n".format( self.output_channel, operator, ";".join(self.main_forks))] self._context = {**self._context, **{"forks": "".join(self.forks), "output_channel": self.output_channel}}
[docs] def set_secondary_channel(self, source, channel_list): """ General purpose method for setting a secondary channel This method allows a given source channel to be forked into one or more channels and sets those forks in the :py:attr:`Process.forks` attribute. Both the source and the channels in the ``channel_list`` argument must be the final channel strings, which means that this method should be called only after setting the main channels. If the source is not a main channel, this will simply create a fork or set for every channel in the ``channel_list`` argument list:: SOURCE_CHANNEL_1.into{SINK_1;SINK_2} If the source is a main channel, this will apply some changes to the output channel of the process, to avoid overlapping main output channels. For instance, forking the main output channel for process 2 would create a ``MAIN_2.into{...}``. The issue here is that the ``MAIN_2`` channel is expected as the input of the next process, but now is being used to create the fork. To solve this issue, the output channel is modified into ``_MAIN_2``, and the fork is set to the channels provided channels plus the ``MAIN_2`` channel:: _MAIN_2.into{MAIN_2;MAIN_5;...} Parameters ---------- source : str String with the name of the source channel channel_list : list List of channels that will receive a fork of the secondary channel """ logger.debug("Setting secondary channel for source '{}': {}".format( source, channel_list)) source = "{}_{}".format(source, self.pid) # Removes possible duplicate channels, when the fork is terminal channel_list = sorted(list(set(channel_list))) # When there is only one channel to fork into, use the 'set' operator # instead of 'into' op = "set" if len(channel_list) == 1 else "into" self.forks.append("\n{}.{}{{ {} }}\n".format( source, op, ";".join(channel_list))) logger.debug("Setting forks attribute to: {}".format(self.forks)) self._context = {**self._context, **{"forks": "\n".join(self.forks)}}
[docs] def update_attributes(self, attr_dict): """Updates the directives attribute from a dictionary object. This will only update the directives for processes that have been defined in the subclass. Parameters ---------- attr_dict : dict Dictionary containing the attributes that will be used to update the process attributes and/or directives. """ # Update directives # Allowed attributes to write valid_directives = ["pid", "ignore_type", "ignore_pid", "extra_input", "group", "input_type"] for attribute, val in attr_dict.items(): # If the attribute has a valid directive key, update that # directive if attribute in valid_directives and hasattr(self, attribute): setattr(self, attribute, val) # The params attribute is special, in the sense that it provides # information for the self.params attribute. elif attribute == "params": for name, value in val.items(): if name in self.params: self.params[name]["default"] = value else: raise eh.ProcessError( "The parameter name '{}' does not exist for " "component '{}'".format(name, self.template)) else: for p in self.directives: self.directives[p][attribute] = val
[docs]class Compiler(Process): """Extends the Process methods to status-type processes """ def __init__(self, **kwargs): super().__init__(**kwargs) self.ignore_type = True self.link_start = None
[docs] def set_compiler_channels(self, channel_list, operator="mix"): """General method for setting the input channels for the status process Given a list of status channels that are gathered during the pipeline construction, this method will automatically set the input channel for the status process. This makes use of the ``mix`` channel operator of nextflow for multiple channels:: STATUS_1.mix(STATUS_2,STATUS_3,...) This will set the ``status_channels`` key for the ``_context`` attribute of the process. Parameters ---------- channel_list : list List of strings with the final name of the status channels operator : str Specifies the operator used to join the compiler channels. Available options are 'mix'and 'join'. """ if not channel_list: raise eh.ProcessError("At least one status channel must be " "provided to include this process in the " "pipeline") if len(channel_list) == 1: logger.debug("Setting only one status channel: {}".format( channel_list[0])) self._context = {"compile_channels": channel_list[0]} else: first_status = channel_list[0] if operator == "mix": lst = ",".join(channel_list[1:]) s = "{}.mix({})".format(first_status, lst) elif operator == "join": s = first_status for ch in channel_list[1:]: s += ".join({})".format(ch) s += ".map{ ot -> [ ot[0], ot[1..-1] ] }" logger.debug("Status channel string: {}".format(s)) self._context = {"compile_channels": s}
[docs]class Init(Process): def __init__(self, **kwargs): super().__init__(**kwargs) self.input_type = None self.output_type = "raw" self.status_channels = []
[docs] def set_raw_inputs(self, raw_input): """Sets the main input channels of the pipeline and their forks. The ``raw_input`` dictionary input should contain one entry for each input type (fastq, fasta, etc). The corresponding value should be a dictionary/json with the following key:values: - ``channel``: Name of the raw input channel (e.g.: channel1) - ``channel_str``: The nextflow definition of the channel and eventual checks (e.g.: channel1 = Channel.fromPath(param)) - ``raw_forks``: A list of channels to which the channel name will for to. Each new type of input parameter is automatically added to the :attr:`params` attribute, so that they are automatically collected for the pipeline description and help. Parameters ---------- raw_input : dict Contains an entry for each input type with the channel name, channel string and forks. """ logger.debug("Setting raw inputs using raw input dict: {}".format( raw_input)) primary_inputs = [] for input_type, el in raw_input.items(): primary_inputs.append(el["channel_str"]) # Update the process' parameters with the raw input raw_channel = self.RAW_MAPPING[input_type] self.params[input_type] = { "default": raw_channel["default_value"], "description": raw_channel["description"] } op = "set" if len(el["raw_forks"]) == 1 else "into" self.forks.append("\n{}.{}{{ {} }}\n".format( el["channel"], op, ";".join(el["raw_forks"]) )) logger.debug("Setting raw inputs: {}".format(primary_inputs)) logger.debug("Setting forks attribute to: {}".format(self.forks)) self._context = {**self._context, **{"forks": "\n".join(self.forks), "main_inputs": "\n".join(primary_inputs)}}
[docs] def set_secondary_inputs(self, channel_dict): """ Adds secondary inputs to the start of the pipeline. This channels are inserted into the pipeline file as they are provided in the values of the argument. Parameters ---------- channel_dict : dict Each entry should be <parameter>: <channel string>. """ logger.debug("Setting secondary inputs: {}".format(channel_dict)) secondary_input_str = "\n".join(list(channel_dict.values())) self._context = {**self._context, **{"secondary_inputs": secondary_input_str}}
[docs] def set_extra_inputs(self, channel_dict): """Sets the initial definition of the extra input channels. The ``channel_dict`` argument should contain the input type and destination channel of each parameter (which is the key):: channel_dict = { "param1": { "input_type": "fasta" "channels": ["abricate_2_3", "chewbbaca_3_4"] } } Parameters ---------- channel_dict : dict Dictionary with the extra_input parameter as key, and a dictionary as a value with the input_type and destination channels """ extra_inputs = [] for param, info in channel_dict.items(): # Update the process' parameters with the raw input raw_channel = self.RAW_MAPPING[info["input_type"]] self.params[param] = { "default": raw_channel["default_value"], "description": raw_channel["description"] } channel_name = "IN_{}_extraInput".format(param) channel_str = self.RAW_MAPPING[info["input_type"]]["channel_str"] extra_inputs.append("{} = {}".format(channel_name, channel_str.format(param))) op = "set" if len(info["channels"]) == 1 else "into" extra_inputs.append("{}.{}{{ {} }}".format( channel_name, op, ";".join(info["channels"]))) self._context = { **self._context, **{"extra_inputs": "\n".join(extra_inputs)} }
[docs]class StatusCompiler(Compiler): """Status compiler process template interface This special process receives the status channels from all processes in the generated pipeline. """ def __init__(self, **kwargs): super().__init__(**kwargs)
[docs]class ReportCompiler(Compiler): """Reports compiler process template interface This special process receives the report channels from all processes in the generated pipeline. """ def __init__(self, **kwargs): super().__init__(**kwargs)
[docs]class PatlasConsensus(Compiler): """Patlas consensus compiler process template interface This special process receives the channels associated with the ``patlas_consensus`` key. """ def __init__(self, **kwargs): super().__init__(**kwargs)