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NAME

Disbatch::Web - Disbatch Command Interface (JSON REST API and web browser interface to Disbatch).

VERSION

version 4.102

EXPORTED

parse_params, send_json_options, template

SUBROUTINES

init(config_file => $config_file)

Parameters: path to the Disbatch config file. Default is /etc/disbatch/config.json.

Initializes the settings for the web server, including loading any custom routes via config.web_extensions (see "CUSTOM ROUTES" below).

Returns nothing.

template($template, $params)

Parameters: template (.tt) file name in the config.views_dir directory, HASH of parameters for the template.

Creates a web page based on the passed data.

Sets Content-Type to text/html.

Returns the generated html document.

NOTE: this sub is automatically exported, so any package using Disbatch::Web can call it.

parse_params

Parameters: none

Parses request parameters in the following order:

* from the request body if the Content-Type is application/x-www-form-urlencoded

* from the request body if the Content-Type is application/json

* from the request query otherwise

It then puts any fields starting with . into their own HASH $options.

Returns the HASH of the parsed request parameters, and if wantarray also returns the HASH of options.

NOTE: this sub is automatically exported, so any package using Disbatch::Web can call it.

send_json_options

Parameters: none

Used to enable the following options when returning JSON: allow_blessed, canonical, and convert_blessed.

Returns a list of key/value pairs of options to pass to send_json.

NOTE: this sub is automatically exported, so any package using Disbatch::Web can call it.

parse_accept

Parameters: none

Parses Accept header.

Returns a HASH where keys are types and values are q-factor weights.

want_json

Parameters: none

Returns true if Accept header has application/json with a higher q-factor weight than text/html.

Note: if not specified, text/html has an assumed q-factor weight of 0 and application/json has an assumed q-factor weight of 1.

get_nodes

Parameters: none

Returns an array of node objects defined, with timestamp stringified and id the stringified _id.

get_plugins

Parameters: none

Returns a HASH of defined queues plugins and any defined config.plugins, where values match the keys.

get_queue_oid($queue)

Parameters: Queue ID as a string, or queue name.

Returns a MongoDB::OID object representing this queue's _id.

create_tasks($queue_id, $tasks)

Parameters: MongoDB::OID object of the queue _id, ARRAY of task params.

Creates one queued task document for the given queue _id per $tasks entry. Each $task entry becomes the value of the params field of the document.

Returns: the repsonse object from a MongoDB::Collection#insert_many request.

post_tasks($legacy_params)

Parameters: legacy params (optional, used by routes in Disbatch::Web::Tasks), also parses request parameters

Handles creating tasks to insert, and then creates them via create_tasks(). See POST /tasks below for usage.

Returns the resonse of create_tasks() as JSON with the key the ref type of the response and the value the response turned into a HASH, or on error sets HTTP status to 400 and returns JSON of {"error":message}.

_munge_tasks($tasks, $options)

Parameters: ARRAY of task documents, HASH of param options

Options handled are .terse, .full, and .epoch, all booleans.

If .terse, stdout and stderr values of each document will be [terse mode] if defined and not a MongoDB::OID object. Else if .full, stdout and stderr values of each document will be actual content instead of MongoDB::OID objects. If .epoch, ctime and mtime will be turned into hires_epoch (ex: 1548272576.574) insteaad of stringified (ex: 2019-01-23T19:42:56) if they are DateTime objects.

Returns nothing, modifies passed tasks.

get_balance

Parameters: none

Returns a HASH of the balance doc without the _id field, with the following added: field known_queues with value an ARRAY of all existing queue names, field settings with value the HASH of config.balance. If the balance doc does not exist, the field notice with value balance document not found is added.

post_balance

Parameters: none (but parses request parameters, see POST /balance below)

Sets the balance document fields given in the request parameters to the given values.

Returns { status => 'success: queuebalance modified' } on success, or { status => 'failed: invalid json passed ' . $_ } with HTTP status of 400 on error.

check_disbatch

Parameters: none

Checks if Disbatch nodes exist and determines if any have been running within the last 60 seconds.

Returns { status => 'WARNING', message => 'No Disbatch nodes found' } if no nodes, { status => 'OK', message => 'Disbatch is running on one or more nodes', nodes => $status } if at least one node recently running, or { status => 'CRITICAL', message => 'No active Disbatch nodes found', nodes => $status } if not. On error, returns { status => 'CRITICAL', message => "Could not get current Disbatch nodes: $_" }.

check_queuebalance

Parameters: none

Checks if QueueBalance has been running within the last 60 seconds.

Returns { status => 'OK', message => 'queuebalance disabled' } if config.balance.enabled is false. If the balance doc has status of CRITICAL and no timestamp, returns { status => 'CRITICAL', message => $message }. If the timestamp value is older than 60 seconds, returns { status => 'CRITICAL' , message => "queuebalanced not running for ${seconds}s" }. If the status value is not OK, WARNING, or CRITICAL, returns { status => 'CRITICAL', message => 'queuebalanced unknown status', result => $doc }. Otherwise returns the doc: { status => $status, message => $message, timestamp => $timestamp }.

checks

Parameters: none

Checks the status of Disbatch and QueueBalance.

If config.monitoring, calls check_disbatch() and check_queuebalance().

Returns { disbatch => check_disbatch() , queuebalance => check_queuebalance() } if config.monitoring is true, otherwise { disbatch => { status => 'OK', message => 'monitoring disabled' }, queuebalance => $checks->{queuebalance} = { status => 'OK', message => 'monitoring disabled' } }.

get_indexes($coll)

Parameters: MongoDB::Collection.

Returns an ARRAY of ARRAYs of current indexes for the given collection.

Note: _id is turned into id because of Template.

invalid_params($params, $indexes)

Parameters: MongoDB query params HASH, current existsing collection indexes HASH

Returns a list of all params passed which do not match the given indexes. If the list is empty, the params are good.

Note: only looks at keys in $params, not their values.

params_to_query($params, $oid_keys)

Parameters: HASH form parameters for a MongoDB query, ARRAY of index keys whose values are always ObjectIds, excluding _id.

Turns fields from an HTTP request into a query suitable for MongoDB::Collection.

    Skips key/value pairs where the value is the empty string.

    If a key is id or is in $oid_keys, turns the value(s) which should be hex strings into MongoDB::OID objects.

    Otherwise if a value (or first element of an ARRAY value) looks like a number, ensures the value (or elements) is a Perl number.

    Any values which are ARRAYs are turned into queries joined by $or.

    If more than one key/value pair, they are joined into an $and query.

Returns a query to pass a MongoDB::Collection object.

query($params, $options, $title, $oid_keys, $collection, $path, $raw, $indexes)

Performs a MongoDB query (count or find).

Parameters: HTTP params (HASH), options (HASH), title (string), OID keys (ARRAY), MongoDB::Collection object, form action path (string), return raw result (boolean), indexes (ARRAY of arrays).

Form action path should be from request->{path}.

Options can be .count, .fields to return, .limit, and .skip.

Raw and indexes key are optional -- raw defaults to 0, and indexes are queried if undef.

Returns the result of the query as a HASH or ARRAY, or an error HASH.

NOTE: I hate this code. Read it to determine the formats it might return.

JSON ROUTES

NOTE: all JSON routes use send_json_options, documented above.

GET /info

Parameters: none.

Returns an object with the following fields: database (the name of the MongoDB database used), web_extensions (an array of configured web extensions for custom routes), and routes (an object where fields are HTTP verbs and values are routes in the ordered configured).

Note: new in Disbatch 4.2

GET /nodes

Parameters: none.

Returns an Array of node Objects defined (with id the stringified _id) on success, { "error": "Could not get current nodes: $_" } on error.

Sets HTTP status to 400 on error.

Note: new in Disbatch 4

GET /nodes/:node

URL: :node is the _id if it matches /\A[0-9a-f]{24}\z/, or node name if it does not.

Parameters: none.

Returns node Object (with id the stringified _id) on success, { "error": "Could not get node $node: $_" } on error.

Sets HTTP status to 400 on error.

Note: new in Disbatch 4

POST /nodes/:node

URL: :node is the _id if it matches /\A[0-9a-f]{24}\z/, or node name if it does not.

Parameters: { "maxthreads": maxthreads }

"maxthreads" is a non-negative integer or null

Returns { ref $res: Object } or { ref $res: Object, "error": error_string_or_reponse_object }

Sets HTTP status to 400 on error.

Note: new in Disbatch 4

GET /plugins

Parameters: none.

Returns an Array of allowed plugin names.

Should never fail.

Note: replaces /queue-prototypes-json

GET /queues

Parameters: none.

Returns an Array of queue Objects on success, { "error": "Could not get current queues: $_" } on error.

Each item has the following keys: id, plugin, name, threads, queued, running, completed

Sets HTTP status to 400 on error.

Note: replaces /scheduler-json

GET /queues/:queue

URL: :queue is the _id if it matches /\A[0-9a-f]{24}\z/, or name if it does not.

Parameters: none.

Returns a queue Object on success, { "error": "Could not get current queues: $_" } on error.

Each item has the following keys: id, plugin, name, threads, queued, running, completed

Sets HTTP status to 400 on error.

POST /queues

Create a new queue.

Parameters: { "name": name, "plugin": plugin }

name is the desired name for the queue (must be unique), plugin is the plugin name for the queue.

Returns: { ref $res: Object, "id": $inserted_id } on success; { "error": "name and plugin required" }, { "error": "Invalid param", "param": $param }, or { "error": "Unknown plugin", "plugin": $plugin } on input error; or { ref $res: Object, "id": null, "error": "$res" } on MongoDB error.

Sets HTTP status to 400 on error.

Note: replaces /start-queue-json

POST /queues/:queue

URL: :queue is the _id if it matches /\A[0-9a-f]{24}\z/, or name if it does not.

Parameters: { "name": name, "plugin": plugin, "threads": threads }

name is the new name for the queue (must be unique), plugin is the new plugin name for the queue (must be defined in the config file), threads must be a non-negative integer. Only one of name, plugin, and threads is required, but any combination is allowed.

Returns { ref $res: Object } or { "error": error }

Sets HTTP status to 400 on error.

Note: replaces /set-queue-attr-json

DELETE /queues/:queue

Deletes the specified queue.

URL: :queue is the _id if it matches /\A[0-9a-f]{24}\z/, or name if it does not.

Parameters: none

Returns: { ref $res: Object } on success, or { ref $res: Object, "error": "$res" } on error.

Sets HTTP status to 400 on error.

Note: replaces /delete-queue-json

GET /tasks

Parameters: anything indexed on the tasks collection, as well as any dot options.

Options can be .count, .fields to return, query .limit and .skip, .terse or .full output, dates as .epoch, and .pretty print JSON result.

Performs a search of tasks, returning either JSON or a web page.

If want_json() (based on the Accept header), returns a JSON array (which may be pretty-printed if specified in the parameters) of task documents, or on error an object with an error field (and possibly other fields).

Otherwise, if no parameters returns a web form to perform a search of indexed fields. If parameters, returns a web page of results or error.

Sets HTTP status to 400 on error.

Note: new in 4.2, replaces POST /tasks/search

GET /tasks/:id

Parameters: Task OID in URL

Returns the task matching OID as JSON, or { "error": "no task with id :id" } and status 404 if OID not found. Or, via a web browser (based on Accept header value), returns the task matching OID with some formatting, or No tasks found matching query if OID not found.

POST /tasks

Parameters: { "queue": queue, "params": [single_task_params, another_task_params, ...] } or { "queue": queue, "params": generic_task_params, "collection": collection, "filter": filter }.

queue is the _id if it matches /\A[0-9a-f]{24}\z/, or name if it does not.

collection is a MongoDB collection name.

filter is a filter expression (query) object for the :collection collection.

params depends on if passing a collection and filter or not.

    If not, params is an array of objects, each of which will be inserted as-is as the params value in created tasks.

    Otherwise, params is an object of generic task params. To insert a document value from a query into the params, prefix the desired key name with document. as a value.

Returns: { ref $res: Object } on success; { "error": "params must be a JSON array of task params" }, { "error": "filter and params required and must be name/value objects" } or { "error": "queue not found" } on input error; { "error": "Could not iterate on collection $collection: $error" } on query error, or { ref $res: Object, "error": "Unknown error" } on MongoDB error.

Sets HTTP status to 400 on error.

Note: new in 4.2, replaces POST /tasks/:queue and POST /tasks/:queue/:collection

GET /balance

Parameters: none

Returns a web page to view and update Queue Balance settings if the Accept header wants text/html, otherwise returns a pretty JSON result of get_balance

POST /balance

Parameters: { "max_tasks": max_tasks, "queues": queues, "disabled": disabled }

max_tasks is a HASH where keys match /^[*0-6] (?:[01]\d|2[0-3]):[0-5]\d$/ (that is, 0..6 or * for DOW, followed by a space and a 24-hour time) and values are non-negative integers.

queues is an ARRAY of ARRAYs of queue names which must exist

disabled is a timestamp which must be in the future (optional)

Sets the balance document fields given in the above parameters to the given values.

Returns JSON {"status":"success: queuebalance modified"} on success, or {"status":"failed: invalid json passed " . $_} with HTTP status of 400 on error.

GET /monitoring

Parameters: none

Checks the status of Disbatch and QueueBalance.

Monitoring is controlled by setting config.monitoring and config.balance.enabled.

Returns as JSON the result of checks(), documented above.

CUSTOM ROUTES

You can set an object of package names and arguments (can be null) to web_extensions in the config file to load any custom routes and call init($disbatch, $arguments) if available. Note that if a request which matches your custom route is also matched by an above route, your custom route will never be called. If a custom route package needs to interface with Disbatch or have any arguments passed to it, it should have the following:

    my $disbatch;

    sub init {
        ($disbatch, my $args) = @_;
        # do whatever you may need to do with $args
    }

For examples see Disbatch::Web::Files (which is automatically loaded at the end of init(), after any custom routes) and Disbatch::Web::Tasks (not loaded by default).

BROWSER ROUTES

GET /

Returns the contents of "/index.html" – the queue browser page.

GET qr{^/}

Returns the contents of the request path.

Note: this is loaded from Disbatch::Web::Files.

SEE ALSO

Disbatch

Disbatch::Roles

Disbatch::Plugin::Demo

disbatchd

disbatch.pl

task_runner

disbatch-create-users

AUTHORS

Ashley Willis <awillis@synacor.com>

Matt Busigin

COPYRIGHT AND LICENSE

This software is Copyright (c) 2015, 2016, 2019 by Ashley Willis.

This is free software, licensed under:

  The Apache License, Version 2.0, January 2004

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