Class: LogStash::Outputs::Loki

Inherits:
Base
  • Object
show all
Includes:
Loki
Defined in:
lib/logstash/outputs/loki.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Loki

#to_ns

Instance Attribute Details

#batchObject (readonly)

Returns the value of attribute batch.



62
63
64
# File 'lib/logstash/outputs/loki.rb', line 62

def batch
  @batch
end

Instance Method Details

#add_entry_to_batch(e) ⇒ Object

Add an entry to the current batch returns false if the batch is full and the entry can’t be added.



183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
# File 'lib/logstash/outputs/loki.rb', line 183

def add_entry_to_batch(e)
  line = e.entry['line']
  # we don't want to send empty lines.
  return true if line.to_s.strip.empty?

  if @batch.nil?
    @batch = Batch.new(e)
    return true
  end

  if @batch.size_bytes_after(line) > @batch_size
    return false
  end
  @batch.add(e)
  return true
end

#batch_sizeObject

‘Maximum batch size to accrue before pushing to loki. Defaults to 102400 bytes’



39
# File 'lib/logstash/outputs/loki.rb', line 39

config :batch_size, :validate => :number, :default => 102400, :required => false

#batch_waitObject

‘Interval in seconds to wait before pushing a batch of records to loki. Defaults to 1 second’



42
# File 'lib/logstash/outputs/loki.rb', line 42

config :batch_wait, :validate => :number, :default => 1, :required => false

#ca_certObject

‘TLS’



30
# File 'lib/logstash/outputs/loki.rb', line 30

config :ca_cert, :validate => :path, :required => false

#certObject

‘Client certificate’



26
# File 'lib/logstash/outputs/loki.rb', line 26

config :cert, :validate => :path, :required => false

#closeObject



210
211
212
213
214
215
216
217
218
219
220
221
# File 'lib/logstash/outputs/loki.rb', line 210

def close
  @entries.close
  @mutex.synchronize do
    @stop = true
  end
  @batch_wait_thread.join
  @batch_size_thread.join

  # if by any chance we still have a forming batch, we need to send it.
  send(@batch) if !@batch.nil?
  @batch = nil
end

#include_fieldsObject

‘An array of fields to map to labels, if defined only fields in this list will be mapped.’



51
# File 'lib/logstash/outputs/loki.rb', line 51

config :include_fields, :validate => :array, :default => [], :required => false

#insecure_skip_verifyObject

‘Disable server certificate verification’



33
# File 'lib/logstash/outputs/loki.rb', line 33

config :insecure_skip_verify, :validate => :boolean, :default => false, :required => false

#is_batch_expiredObject



200
201
202
# File 'lib/logstash/outputs/loki.rb', line 200

def is_batch_expired
  return !@batch.nil? && @batch.age() >= @batch_wait
end

#load_sslObject



142
143
144
145
# File 'lib/logstash/outputs/loki.rb', line 142

def load_ssl
  @cert = OpenSSL::X509::Certificate.new(File.read(@cert)) if @cert
  @key = OpenSSL::PKey.read(File.read(@key)) if @key
end

#loki_http_request(payload) ⇒ Object



233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
# File 'lib/logstash/outputs/loki.rb', line 233

def loki_http_request(payload)
  req = Net::HTTP::Post.new(
    @uri.request_uri
  )
  req.add_field('Content-Type', 'application/json')
  req.add_field('X-Scope-OrgID', @tenant_id) if @tenant_id
  req['User-Agent']= 'loki-logstash'
  req.basic_auth(@username, @password) if @username
  req.body = payload

  opts = ssl_opts(@uri)

  @logger.debug("sending #{req.body.length} bytes to loki")
  retry_count = 0
  delay = @min_delay
  begin
    res = Net::HTTP.start(@uri.host, @uri.port, **opts) { |http|
      http.request(req)
    }
    return res if !res.nil? && res.code.to_i != 429 && res.code.to_i.div(100) != 5
    raise StandardError.new res
  rescue StandardError => e
    retry_count += 1
    @logger.warn("Failed to send batch, attempt: #{retry_count}/#{@retries}", :error_inspect => e.inspect, :error => e)
    if retry_count < @retries
      sleep delay
      if delay * 2 <= @max_delay
        delay = delay * 2
      else
        delay = @max_delay
      end
      retry
    else
      @logger.error("Failed to send batch", :error_inspect => e.inspect, :error => e)
      return res
    end
  end
end

#max_batch_sizeObject



95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
# File 'lib/logstash/outputs/loki.rb', line 95

def max_batch_size
  loop do
    @mutex.synchronize do
      return if @stop
    end

    e = @entries.deq
    return if e.nil?

    @mutex.synchronize do
      if !add_entry_to_batch(e)
        @logger.debug("Max batch_size is reached. Sending batch to loki")
        send(@batch)
        @batch = Batch.new(e)
      end
    end
  end
end

#max_batch_waitObject



114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
# File 'lib/logstash/outputs/loki.rb', line 114

def max_batch_wait
  # minimum wait frequency is 10 milliseconds
 min_wait_checkfrequency = 1/100
 max_wait_checkfrequency = @batch_wait
 if max_wait_checkfrequency < min_wait_checkfrequency
  max_wait_checkfrequency = min_wait_checkfrequency
  end

  loop do
    @mutex.synchronize do
      return if @stop
    end

    sleep(max_wait_checkfrequency)
    if is_batch_expired
      @mutex.synchronize do
        @logger.debug("Max batch_wait time is reached. Sending batch to loki")
        send(@batch)
        @batch = nil
      end
    end
  end
end

#max_delayObject

‘Backoff configuration. Maximum backoff time between retries. Default 300s’



57
# File 'lib/logstash/outputs/loki.rb', line 57

config :max_delay, :validate => :number, :default => 300, :required => false

#message_fieldObject

‘Log line field to pick from logstash. Defaults to “message”’



45
# File 'lib/logstash/outputs/loki.rb', line 45

config :message_field, :validate => :string, :default => "message", :required => false

#metadata_fieldsObject

‘An array of fields to map to structure metadata, if defined only fields in this list will be mapped.’



54
# File 'lib/logstash/outputs/loki.rb', line 54

config :metadata_fields, :validate => :array, :default => [], :required => false

#min_delayObject

‘Backoff configuration. Initial backoff time between retries. Default 1s’



48
# File 'lib/logstash/outputs/loki.rb', line 48

config :min_delay, :validate => :number, :default => 1, :required => false

#receive(event) ⇒ Object



206
207
208
# File 'lib/logstash/outputs/loki.rb', line 206

def receive(event)
  @entries << Entry.new(event, @message_field, @include_fields, @metadata_fields)
end

#registerObject



64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
# File 'lib/logstash/outputs/loki.rb', line 64

def register
  @uri = URI.parse(@url)
  unless @uri.is_a?(URI::HTTP) || @uri.is_a?(URI::HTTPS)
    raise LogStash::ConfigurationError, "url parameter must be valid HTTP, currently '#{@url}'"
  end

  if @min_delay > @max_delay
    raise LogStash::ConfigurationError, "Min delay should be less than Max delay, currently 'Min delay is #{@min_delay} and Max delay is #{@max_delay}'"
  end

  @logger.info("Loki output plugin", :class => self.class.name)

  # initialize Queue and Mutex
  @entries = Queue.new
  @mutex = Mutex.new
  @stop = false

  # create nil batch object.
  @batch = nil

  # validate certs
  if ssl_cert?
    load_ssl
    validate_ssl_key
  end

  # start batch_max_wait and batch_max_size threads
  @batch_wait_thread = Thread.new{max_batch_wait()}
  @batch_size_thread = Thread.new{max_batch_size()}
end

#retriesObject

‘Backoff configuration. Maximum number of retries to do’



60
# File 'lib/logstash/outputs/loki.rb', line 60

config :retries, :validate => :number, :default => 10, :required => false

#send(batch) ⇒ Object



223
224
225
226
227
228
229
230
231
# File 'lib/logstash/outputs/loki.rb', line 223

def send(batch)
  payload = batch.to_json
  res = loki_http_request(payload)
  if res.is_a?(Net::HTTPSuccess)
    @logger.debug("Successfully pushed data to loki")
  else
    @logger.debug("failed payload", :payload => payload)
  end
end

#singleObject

‘A single instance of the Output will be shared among the pipeline worker threads’



16
# File 'lib/logstash/outputs/loki.rb', line 16

concurrency :single

#ssl_cert?Boolean

Returns:

  • (Boolean)


138
139
140
# File 'lib/logstash/outputs/loki.rb', line 138

def ssl_cert?
  !@key.nil? && !@cert.nil?
end

#ssl_opts(uri) ⇒ Object



153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
# File 'lib/logstash/outputs/loki.rb', line 153

def ssl_opts(uri)
  opts = {
    use_ssl: uri.scheme == 'https'
  }

   # disable server certificate verification
  if @insecure_skip_verify
    opts = opts.merge(
      verify_mode: OpenSSL::SSL::VERIFY_NONE
    )
  end

  if !@cert.nil? && !@key.nil?
    opts = opts.merge(
      verify_mode: OpenSSL::SSL::VERIFY_PEER,
      cert: @cert,
      key: @key
    )
  end

  unless @ca_cert.nil?
    opts = opts.merge(
      ca_file: @ca_cert
    )
  end
  opts
end

#tenant_idObject

‘Loki Tenant ID’



36
# File 'lib/logstash/outputs/loki.rb', line 36

config :tenant_id, :validate => :string, :required => false

#urlObject

‘Loki URL’



19
# File 'lib/logstash/outputs/loki.rb', line 19

config :url, :validate => :string, :required => true

#usernameObject

‘BasicAuth credentials’



22
# File 'lib/logstash/outputs/loki.rb', line 22

config :username, :validate => :string, :required => false

#validate_ssl_keyObject



147
148
149
150
151
# File 'lib/logstash/outputs/loki.rb', line 147

def validate_ssl_key
  if !@key.is_a?(OpenSSL::PKey::RSA) && !@key.is_a?(OpenSSL::PKey::DSA)
    raise LogStash::ConfigurationError, "Unsupported private key type '#{@key.class}''"
  end
end