logs.js

/**
 * Copyright 2017, Google, Inc.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

'use strict';

function writeLogEntry (logName) {
  // [START logging_write_log_entry]
  // Imports the Google Cloud client library
  const Logging = require('@google-cloud/logging');

  // Instantiates a client
  const logging = Logging();

  // The log to write to, e.g. "my-log"
  // const logName = "my-log";

  const log = logging.log(logName);

  // Modify this resource to match a resource in your project
  // See https://cloud.google.com/logging/docs/api/ref_v2beta1/rest/v2beta1/MonitoredResource
  const resource = {
    // This example targets the "global" resource for simplicity
    type: 'global'
  };

  // A text log entry
  const entry = log.entry({ resource: resource }, 'Hello, world!');

  // A structured log entry
  const secondEntry = log.entry({ resource: resource }, {
    name: 'King Arthur',
    quest: 'Find the Holy Grail',
    favorite_color: 'Blue'
  });

  // Save the two log entries. You can write entries one at a time, but it is
  // best to write multiple entires together in a batch.
  log.write([entry, secondEntry])
    .then(() => {
      console.log(`Wrote to ${logName}`);
    })
    .catch((err) => {
      console.error('ERROR:', err);
    });
  // [END logging_write_log_entry]
}

function loggingBunyan () {
  // [START logging_bunyan]
  const bunyan = require('bunyan');

  // Imports the Google Cloud client library for Bunyan
  const LoggingBunyan = require('@google-cloud/logging-bunyan');

  // Instantiates a Bunyan Stackdriver Logging client
  const loggingBunyan = LoggingBunyan();

  // Create a Bunyan logger that streams to Stackdriver Logging
  // Logs will be written to: "projects/YOUR_PROJECT_ID/logs/bunyan_log"
  const logger = bunyan.createLogger({
    // The JSON payload of the log as it appears in Stackdriver Logging
    // will contain "name": "my-service"
    name: 'my-service',
    // log at 'info' and above
    level: 'info',
    streams: [
      // Log to the console
      { stream: process.stdout },
      // And log to Stackdriver Logging
      loggingBunyan.stream()
    ]
  });

  // Writes some log entries
  logger.error('warp nacelles offline');
  logger.info('shields at 99%');
  // [END logging_bunyan]
}

function loggingWinston () {
  // [START logging_winston]
  const winston = require('winston');
  const Logger = winston.Logger;
  const Console = winston.transports.Console;

  // Imports the Google Cloud client library for Winston
  const LoggingWinston = require('@google-cloud/logging-winston');

  // Instantiates a Winston Stackdriver Logging client
  const loggingWinston = LoggingWinston();

  // Create a Winston logger that streams to Stackdriver Logging
  // Logs will be written to: "projects/YOUR_PROJECT_ID/logs/winston_log"
  const logger = new Logger({
    level: 'info', // log at 'info' and above
    transports: [
      // Log to the console
      new Console(),
      // And log to Stackdriver Logging
      loggingWinston
    ]
  });

  // Writes some log entries
  logger.error('warp nacelles offline');
  logger.info('shields at 99%');
  // [END logging_winston]
}

function bunyanSetupExplicit () {
  // [START logging_bunyan_setup_explicit]
  // Imports the Google Cloud client library for Bunyan
  const LoggingBunyan = require('@google-cloud/logging-bunyan');

  // Instantiates a client
  const loggingBunyan = LoggingBunyan({
    projectId: 'your-project-id',
    keyFilename: '/path/to/key.json'
  });
  // [END logging_bunyan_setup_explicit]
  console.log(loggingBunyan);
}

function winstonSetupExplicit () {
  // [START logging_winston_setup_explicit]
  // Imports the Google Cloud client library for Winston
  const LoggingWinston = require('@google-cloud/logging-winston');

  // Instantiates a client
  const loggingWinston = LoggingWinston({
    projectId: 'your-project-id',
    keyFilename: '/path/to/key.json'
  });

  // [END logging_winston_setup_explicit]
  console.log(loggingWinston);
}

function writeLogEntryAdvanced (logName, options) {
  // [START logging_write_log_entry_advanced]
  // Imports the Google Cloud client library
  const Logging = require('@google-cloud/logging');

  // Instantiates a client
  const logging = Logging();

  // The log to write to, e.g. "my-log"
  // const logName = "my-log";

  // The request options
  // const options = {
  //   resource: {...},
  //   entry: 'Hello, world!'
  // };

  const log = logging.log(logName);

  // Prepare the entry
  const entry = log.entry({ resource: options.resource }, options.entry);

  // See https://googlecloudplatform.github.io/google-cloud-node/#/docs/logging/latest/logging/log?method=write
  log.write(entry)
    .then(() => {
      console.log(`Wrote to ${logName}`);
    })
    .catch((err) => {
      console.error('ERROR:', err);
    });
  // [END logging_write_log_entry_advanced]
}

function listLogEntries (logName) {
  // [START logging_list_log_entries]
  // Imports the Google Cloud client library
  const Logging = require('@google-cloud/logging');

  // Instantiates a client
  const logging = Logging();

  // The log from which to list entries, e.g. "my-log"
  // const logName = "my-log";

  const log = logging.log(logName);

  // List the most recent entries for a given log
  // See https://googlecloudplatform.github.io/google-cloud-node/#/docs/logging/latest/logging?method=getEntries
  log.getEntries()
    .then((results) => {
      const entries = results[0];

      console.log('Logs:');
      entries.forEach((entry) => {
        const metadata = entry.metadata;
        console.log(`${metadata.timestamp}:`, metadata[metadata.payload]);
      });
    })
    .catch((err) => {
      console.error('ERROR:', err);
    });
  // [END logging_list_log_entries]
}

function listLogEntriesAdvanced (filter, pageSize, orderBy) {
  // [START logging_list_log_entries_advanced]
  // Imports the Google Cloud client library
  const Logging = require('@google-cloud/logging');

  // Instantiates a client
  const logging = Logging();

  // Filter results, e.g. "severity=ERROR"
  // See https://cloud.google.com/logging/docs/view/advanced_filters for more filter information.
  // const filter = 'severity=ERROR';

  // const pageSize = 5;

  // Sort results
  // const orderBy = 'timestamp';

  const options = {
    filter: filter,
    pageSize: pageSize,
    orderBy: orderBy
  };

  // See https://googlecloudplatform.github.io/google-cloud-node/#/docs/logging/latest/logging?method=getEntries
  logging.getEntries(options)
    .then((results) => {
      const entries = results[0];

      console.log('Logs:');
      entries.forEach((entry) => {
        const metadata = entry.metadata;
        console.log(`${metadata.timestamp}:`, metadata[metadata.payload]);
      });
    })
    .catch((err) => {
      console.error('ERROR:', err);
    });
  // [START logging_list_log_entries_advanced]
}

function deleteLog (logName) {
  // [START logging_delete_log]
  // Imports the Google Cloud client library
  const Logging = require('@google-cloud/logging');

  // Instantiates a client
  const logging = Logging();

  // The log to delete, e.g. "my-log"
  // const logName = "my-log";

  const log = logging.log(logName);

  // Deletes a logger and all its entries.
  // Note that a deletion can take several minutes to take effect.
  // See https://googlecloudplatform.github.io/google-cloud-node/#/docs/logging/latest/logging/log?method=delete
  log.delete()
    .then(() => {
      console.log(`Deleted log: ${logName}`);
    })
    .catch((err) => {
      console.error('ERROR:', err);
    });
  // [END logging_delete_log]
}

// The command-line program
const cli = require(`yargs`)
  .demand(1)
  .command('list', 'Lists log entries, optionally filtering, limiting, and sorting results.', {
    filter: {
      alias: 'f',
      type: 'string',
      requiresArg: true,
      description: 'Only log entries matching the filter are written.'
    },
    limit: {
      alias: 'l',
      type: 'number',
      requiresArg: true,
      description: 'Maximum number of results to return.'
    },
    sort: {
      alias: 's',
      type: 'string',
      requiresArg: true,
      description: 'Sort results.'
    }
  }, (opts) => {
    listLogEntriesAdvanced(opts.filter, opts.limit, opts.sort);
  })
  .command('list-simple <logName>', 'Lists log entries.', {}, (opts) => listLogEntries(opts.logName))
  .command('write <logName> <resource> <entry>', 'Writes a log entry to the specified log.', {}, (opts) => {
    try {
      opts.resource = JSON.parse(opts.resource);
    } catch (err) {
      console.error('"resource" must be a valid JSON string!');
      return;
    }

    try {
      opts.entry = JSON.parse(opts.entry);
    } catch (err) {}

    writeLogEntryAdvanced(opts.logName, opts);
  })
  .command('write-simple <logName>', 'Writes a basic log entry to the specified log.', {}, (opts) => {
    writeLogEntry(opts.logName);
  })
  .command('bunyan', 'Writes some logs entries to Stackdriver Logging via Winston.', {}, loggingBunyan)
  .command('bunyan-setup', 'Setup up the Bunyan logger with explicit credentianls.', {}, bunyanSetupExplicit)
  .command('winston', 'Writes some logs entries to Stackdriver Logging via Winston.', {}, loggingWinston)
  .command('winston-setup', 'Setup up the Winston logger with explicit credentianls.', {}, winstonSetupExplicit)
  .command('delete <logName>', 'Deletes the specified Log.', {}, (opts) => {
    deleteLog(opts.logName);
  })
  .example('node $0 list', 'List all log entries.')
  .example('node $0 list -f "severity=ERROR" -s "timestamp" -l 2', 'List up to 2 error entries, sorted by timestamp ascending.')
  .example(`node $0 list -f 'logName="my-log"' -l 2`, 'List up to 2 log entries from the "my-log" log.')
  .example('node $0 write my-log \'{"type":"gae_app","labels":{"module_id":"default"}}\' \'"Hello World!"\'', 'Write a string log entry.')
  .example('node $0 write my-log \'{"type":"global"}\' \'{"message":"Hello World!"}\'', 'Write a JSON log entry.')
  .example('node $0 delete my-log', 'Delete "my-log".')
  .wrap(120)
  .recommendCommands()
  .epilogue(`For more information, see https://cloud.google.com/logging/docs`)
  .help()
  .strict();

if (module === require.main) {
  cli.parse(process.argv.slice(2));
}