Tänapäeval on REST API saanud veebirakenduste arendamisel standardiks, võimaldades jagada arendust sõltumatuteks osadeks. UI jaoks kasutatakse hetkel erinevaid populaarseid raamistikku nagu Angular, React, Vue ja teised. Backend arendajad saavad aga valida suurest keelte ja raamistikku valikust. Täna tahaksin rääkida sellisest raamistikust nagu . Me kasutame seda aktiivselt oma siseprojektides. Kasutades nest ja paketti , loome me lihtsa CRUD rakenduse.
Miks NestJS
Viimasel ajal on JavaScripti kogukonnas ilmunud üsna palju backend raamistikku. Ja kui funktsionaalsuse poolest pakuvad need sarnaseid võimalusi nagu Nest, siis arhitektuuri osas on see kindlasti parem. Järgmised võimalused, mida NestJS pakub, võimaldavad luua tööstuslikke rakendusi ja skaleerida arendust suurte meeskondade jaoks:
- TypeScripti kasutamine peamise arenduskeelana. Kuigi NestJS toetab ka JavaScripti, ei pruugi osa funktsionaalsusest töötada, eriti kui on tegemist kolmandate osapoolte pakettidega;
- DI konteineri olemasolu, mis võimaldab luua nõrkade sidemete komponentide süsteeme;
- Raamistiku funktsioonid on jaotatud sõltumatuteks, omavahel vahetatavaks komponentideks. Näiteks võib selle raamistiku alla kuuluda , kui ka , and database work, designs bindings for , , ;
- NestJS ei sõltu platvormist ning toetab REST, GraphQL, Websockets, gRPC jne.
Raamistik on inspireeritud frontendi raamistikust Angular ja sellel on kontseptuaalselt palju ühist.
NestJS-i paigaldamine ja projekti seadistamine
Nest sisaldab paketti /cli, который позволяет быстро развернуть базовый каркас приложения. Установим глобально данный пакет:
npm install --global @nest/cliPärast paigaldamist genereerime meie rakenduse põhiraami nimega nest-rest. Seda tehakse käsu abil nest new nest-rest.
nest new nest-rest
dmitrii@dmitrii-HP-ZBook-17-G3:~/projects $ nest new nest-rest
Meie rakendusivalmistamine kestab vaid mõned sekundid..
Loo /nest-rest/.prettierrc (51 baiti)
Loo /nest-rest/README.md (3370 baiti)
Loo /nest-rest/nest-cli.json (84 baiti)
Loo /nest-rest/nodemon-debug.json (163 baiti)
Loo /nest-rest/nodemon.json (67 baiti)
Loo /nest-rest/package.json (1805 baiti)
Loo /nest-rest/tsconfig.build.json (97 baiti)
Loo /nest-rest/tsconfig.json (325 baiti)
Loo /nest-rest/tslint.json (426 baiti)
Loo /nest-rest/src/app.controller.spec.ts (617 baiti)
Loo /nest-rest/src/app.controller.ts (274 baiti)
Loo /nest-rest/src/app.module.ts (249 baiti)
Loo /nest-rest/src/app.service.ts (142 baiti)
Loo /nest-rest/src/main.ts (208 baiti)
Loo /nest-rest/test/app.e2e-spec.ts (561 baiti)
Loo /nest-rest/test/jest-e2e.json (183 baiti)
? Millist paketihaldurit soovite kasutada? yarn
Paigaldamine toimib...
Projekti nest-rest loomine õnnestus
Alustamiseks kasutage järgmisi käske:
$ cd nest-rest
$ yarn run start
Aitäh Nest'i paigaldamise eest
Palun kaaluge annetuse tegemist meie avatud kollektiivile
et aidata meil seda paketti hooldada.
Annetage: https://opencollective.com/nestPakettide haldurina valime yarn.
Praegu saate serveri käivitada käsuga npm start ning minna aadressile saate näha peamist lehte. Kuid me ei ole siin selleks ja liikume edasi.
Seame üles andmebaasi kasutamise
Käesolevas artiklis valisin andmebaasihalduseks PostgreSQL. Maitsete üle ei vaielda, minu arvates on see kõige küpsem andmebaasihaldussüsteem, millel on kõik vajalikud funktsioonid. Nagu juba mainitud, pakub Nest andmebaasidega töötamiseks integreerimist erinevate paketidega. Kuna minu valik langes PostgreSQL-ile, siis on mõistlik valida TypeORM ORM-ina. Installime vajalikud paketid andmebaasiga integreerimiseks:
yarn add typeorm @nestjs/typeorm pg
Järjekorras, milleks on iga paketi kasutamine:
- typeorm — pakett, mis sisaldab otseselt ORM-i;
- @nestjs/typeorm — TypeORM pakk NestJS-ile. Lisab moodulid projekti importimiseks ning komplekti abi-dekoraatore;
- pg — PostgreSQL-i draiver.
Okei, paketid on installitud, nüüd on vaja käivitada andmebaas. Andmebaasi käivitamiseks kasutan docker-compose.yml järgmise sisu:
docker-compose.yml
version: '3.1'
services:
db:
image: postgres:11.2
restart: always
environment:
POSTGRES_PASSWORD: example
volumes:
- ../db:/var/lib/postgresql/data
- ./postgresql.conf:/etc/postgresql/postgresql.conf
ports:
- 5432:5432
adminer:
image: adminer
restart: always
ports:
- 8080:8080Kuidas näha, konfigureerib see fail kahe konteineri käivitamise:
- db — see on konteiner, mis sisaldab andmebaasi. Meie juhtudel kasutatakse postgresql versiooni 11.2;
- adminer — andmebaasi halduse tööriist. Pakub veebiliidest andmebaasi vaatamiseks ja haldamiseks.
TCP-ühenduste jaoks lisasin järgmise sisu sisaldava konfiguratsiooni.
postgresql.conf
# -----------------------------
# PostgreSQL configuration file
# -----------------------------
#
# This file consists of lines of the form:
#
# name = value
#
# (The "=" is optional.) Whitespace may be used. Comments are introduced with
# "#" anywhere on a line. The complete list of parameter names and allowed
# values can be found in the PostgreSQL documentation.
#
# The commented-out settings shown in this file represent the default values.
# Re-commenting a setting is NOT sufficient to revert it to the default value;
# you need to reload the server.
#
# This file is read on server startup and when the server receives a SIGHUP
# signal. If you edit the file on a running system, you have to SIGHUP the
# server for the changes to take effect, run "pg_ctl reload", or execute
# "SELECT pg_reload_conf()". Some parameters, which are marked below,
# require a server shutdown and restart to take effect.
#
# Any parameter can also be given as a command-line option to the server, e.g.,
# "postgres -c log_connections=on". Some parameters can be changed at run time
# with the "SET" SQL command.
#
# Memory units: kB = kilobytes Time units: ms = milliseconds
# MB = megabytes s = seconds
# GB = gigabytes min = minutes
# TB = terabytes h = hours
# d = days
#------------------------------------------------------------------------------
# FILE LOCATIONS
#------------------------------------------------------------------------------
# The default values of these variables are driven from the -D command-line
# option or PGDATA environment variable, represented here as ConfigDir.
#data_directory = 'ConfigDir' # use data in another directory
# (change requires restart)
#hba_file = 'ConfigDir/pg_hba.conf' # host-based authentication file
# (change requires restart)
#ident_file = 'ConfigDir/pg_ident.conf' # ident configuration file
# (change requires restart)
# If external_pid_file is not explicitly set, no extra PID file is written.
#external_pid_file = '' # write an extra PID file
# (change requires restart)
#------------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
#------------------------------------------------------------------------------
# - Connection Settings -
listen_addresses = '*'
#listen_addresses = 'localhost' # what IP address(es) to listen on;
# comma-separated list of addresses;
# defaults to 'localhost'; use '*' for all
# (change requires restart)
#port = 5432 # (change requires restart)
#max_connections = 100 # (change requires restart)
#superuser_reserved_connections = 3 # (change requires restart)
#unix_socket_directories = '/tmp' # comma-separated list of directories
# (change requires restart)
#unix_socket_group = '' # (change requires restart)
#unix_socket_permissions = 0777 # begin with 0 to use octal notation
# (change requires restart)
#bonjour = off # advertise server via Bonjour
# (change requires restart)
#bonjour_name = '' # defaults to the computer name
# (change requires restart)
# - TCP Keepalives -
# see "man 7 tcp" for details
#tcp_keepalives_idle = 0 # TCP_KEEPIDLE, in seconds;
# 0 selects the system default
#tcp_keepalives_interval = 0 # TCP_KEEPINTVL, in seconds;
# 0 selects the system default
#tcp_keepalives_count = 0 # TCP_KEEPCNT;
# 0 selects the system default
# - Authentication -
#authentication_timeout = 1min # 1s-600s
#password_encryption = md5 # md5 or scram-sha-256
#db_user_namespace = off
# GSSAPI using Kerberos
#krb_server_keyfile = ''
#krb_caseins_users = off
# - SSL -
#ssl = off
#ssl_ca_file = ''
#ssl_cert_file = 'server.crt'
#ssl_crl_file = ''
#ssl_key_file = 'server.key'
#ssl_ciphers = 'HIGH:MEDIUM:+3DES:!aNULL' # allowed SSL ciphers
#ssl_prefer_server_ciphers = on
#ssl_ecdh_curve = 'prime256v1'
#ssl_min_protocol_version = 'TLSv1'
#ssl_max_protocol_version = ''
#ssl_dh_params_file = ''
#ssl_passphrase_command = ''
#ssl_passphrase_command_supports_reload = off
#------------------------------------------------------------------------------
# RESOURCE USAGE (except WAL)
#------------------------------------------------------------------------------
# - Memory -
#shared_buffers = 32MB # min 128kB
# (change requires restart)
#huge_pages = try # on, off, or try
# (change requires restart)
#temp_buffers = 8MB # min 800kB
#max_prepared_transactions = 0 # zero disables the feature
# (change requires restart)
# Caution: it is not advisable to set max_prepared_transactions nonzero unless
# you actively intend to use prepared transactions.
#work_mem = 4MB # min 64kB
#maintenance_work_mem = 64MB # min 1MB
#autovacuum_work_mem = -1 # min 1MB, or -1 to use maintenance_work_mem
#max_stack_depth = 2MB # min 100kB
#shared_memory_type = mmap # the default is the first option
# supported by the operating system:
# mmap
# sysv
# windows
# (change requires restart)
#dynamic_shared_memory_type = posix # the default is the first option
# supported by the operating system:
# posix
# sysv
# windows
# mmap
# (change requires restart)
# - Disk -
#temp_file_limit = -1 # limits per-process temp file space
# in kB, or -1 for no limit
# - Kernel Resources -
#max_files_per_process = 1000 # min 25
# (change requires restart)
# - Cost-Based Vacuum Delay -
#vacuum_cost_delay = 0 # 0-100 milliseconds (0 disables)
#vacuum_cost_page_hit = 1 # 0-10000 credits
#vacuum_cost_page_miss = 10 # 0-10000 credits
#vacuum_cost_page_dirty = 20 # 0-10000 credits
#vacuum_cost_limit = 200 # 1-10000 credits
# - Background Writer -
#bgwriter_delay = 200ms # 10-10000ms between rounds
#bgwriter_lru_maxpages = 100 # max buffers written/round, 0 disables
#bgwriter_lru_multiplier = 2.0 # 0-10.0 multiplier on buffers scanned/round
#bgwriter_flush_after = 0 # measured in pages, 0 disables
# - Asynchronous Behavior -
#effective_io_concurrency = 1 # 1-1000; 0 disables prefetching
#max_worker_processes = 8 # (change requires restart)
#max_parallel_maintenance_workers = 2 # taken from max_parallel_workers
#max_parallel_workers_per_gather = 2 # taken from max_parallel_workers
#parallel_leader_participation = on
#max_parallel_workers = 8 # maximum number of max_worker_processes that
# can be used in parallel operations
#old_snapshot_threshold = -1 # 1min-60d; -1 disables; 0 is immediate
# (change requires restart)
#backend_flush_after = 0 # measured in pages, 0 disables
#------------------------------------------------------------------------------
# WRITE-AHEAD LOG
#------------------------------------------------------------------------------
# - Settings -
#wal_level = replica # minimal, replica, or logical
# (change requires restart)
#fsync = on # flush data to disk for crash safety
# (turning this off can cause
# unrecoverable data corruption)
#synchronous_commit = on # synchronization level;
# off, local, remote_write, remote_apply, or on
#wal_sync_method = fsync # the default is the first option
# supported by the operating system:
# open_datasync
# fdatasync (default on Linux)
# fsync
# fsync_writethrough
# open_sync
#full_page_writes = on # recover from partial page writes
#wal_compression = off # enable compression of full-page writes
#wal_log_hints = off # also do full page writes of non-critical updates
# (change requires restart)
#wal_buffers = -1 # min 32kB, -1 sets based on shared_buffers
# (change requires restart)
#wal_writer_delay = 200ms # 1-10000 milliseconds
#wal_writer_flush_after = 1MB # measured in pages, 0 disables
#commit_delay = 0 # range 0-100000, in microseconds
#commit_siblings = 5 # range 1-1000
# - Checkpoints -
#checkpoint_timeout = 5min # range 30s-1d
#max_wal_size = 1GB
#min_wal_size = 80MB
#checkpoint_completion_target = 0.5 # checkpoint target duration, 0.0 - 1.0
#checkpoint_flush_after = 0 # measured in pages, 0 disables
#checkpoint_warning = 30s # 0 disables
# - Archiving -
#archive_mode = off # enables archiving; off, on, or always
# (change requires restart)
#archive_command = '' # command to use to archive a logfile segment
# placeholders: %p = path of file to archive
# %f = file name only
# e.g. 'test ! -f /mnt/server/archivedir/%f && cp %p /mnt/server/archivedir/%f'
#archive_timeout = 0 # force a logfile segment switch after this
# number of seconds; 0 disables
# - Archive Recovery -
# These are only used in recovery mode.
#restore_command = '' # command to use to restore an archived logfile segment
# placeholders: %p = path of file to restore
# %f = file name only
# e.g. 'cp /mnt/server/archivedir/%f %p'
# (change requires restart)
#archive_cleanup_command = '' # command to execute at every restartpoint
#recovery_end_command = '' # command to execute at completion of recovery
# - Recovery Target -
# Set these only when performing a targeted recovery.
#recovery_target = '' # 'immediate' to end recovery as soon as a
# consistent state is reached
# (change requires restart)
#recovery_target_name = '' # the named restore point to which recovery will proceed
# (change requires restart)
#recovery_target_time = '' # the time stamp up to which recovery will proceed
# (change requires restart)
#recovery_target_xid = '' # the transaction ID up to which recovery will proceed
# (change requires restart)
#recovery_target_lsn = '' # the WAL LSN up to which recovery will proceed
# (change requires restart)
#recovery_target_inclusive = on # Specifies whether to stop:
# just after the specified recovery target (on)
# just before the recovery target (off)
# (change requires restart)
#recovery_target_timeline = 'latest' # 'current', 'latest', or timeline ID
# (change requires restart)
#recovery_target_action = 'pause' # 'pause', 'promote', 'shutdown'
# (change requires restart)
#------------------------------------------------------------------------------
# REPLICATION
#------------------------------------------------------------------------------
# - Sending Servers -
# Set these on the master and on any standby that will send replication data.
#max_wal_senders = 10 # max number of walsender processes
# (change requires restart)
#wal_keep_segments = 0 # in logfile segments; 0 disables
#wal_sender_timeout = 60s # in milliseconds; 0 disables
#max_replication_slots = 10 # max number of replication slots
# (change requires restart)
#track_commit_timestamp = off # collect timestamp of transaction commit
# (change requires restart)
# - Master Server -
# These settings are ignored on a standby server.
#synchronous_standby_names = '' # standby servers that provide sync rep
# method to choose sync standbys, number of sync standbys,
# and comma-separated list of application_name
# from standby(s); '*' = all
#vacuum_defer_cleanup_age = 0 # number of xacts by which cleanup is delayed
# - Standby Servers -
# These settings are ignored on a master server.
#primary_conninfo = '' # connection string to sending server
# (change requires restart)
#primary_slot_name = '' # replication slot on sending server
# (change requires restart)
#promote_trigger_file = '' # file name whose presence ends recovery
#hot_standby = on # "off" disallows queries during recovery
# (change requires restart)
#max_standby_archive_delay = 30s # max delay before canceling queries
# when reading WAL from archive;
# -1 allows indefinite delay
#max_standby_streaming_delay = 30s # max delay before canceling queries
# when reading streaming WAL;
# -1 allows indefinite delay
#wal_receiver_status_interval = 10s # send replies at least this often
# 0 disables
#hot_standby_feedback = off # send info from standby to prevent
# query conflicts
#wal_receiver_timeout = 60s # time that receiver waits for
# communication from master
# in milliseconds; 0 disables
#wal_retrieve_retry_interval = 5s # time to wait before retrying to
# retrieve WAL after a failed attempt
#recovery_min_apply_delay = 0 # minimum delay for applying changes during recovery
# - Subscribers -
# These settings are ignored on a publisher.
#max_logical_replication_workers = 4 # taken from max_worker_processes
# (change requires restart)
#max_sync_workers_per_subscription = 2 # taken from max_logical_replication_workers
#------------------------------------------------------------------------------
# QUERY TUNING
#------------------------------------------------------------------------------
# - Planner Method Configuration -
#enable_bitmapscan = on
#enable_hashagg = on
#enable_hashjoin = on
#enable_indexscan = on
#enable_indexonlyscan = on
#enable_material = on
#enable_mergejoin = on
#enable_nestloop = on
#enable_parallel_append = on
#enable_seqscan = on
#enable_sort = on
#enable_tidscan = on
#enable_partitionwise_join = off
#enable_partitionwise_aggregate = off
#enable_parallel_hash = on
#enable_partition_pruning = on
# - Planner Cost Constants -
#seq_page_cost = 1.0 # measured on an arbitrary scale
#random_page_cost = 4.0 # same scale as above
#cpu_tuple_cost = 0.01 # same scale as above
#cpu_index_tuple_cost = 0.005 # same scale as above
#cpu_operator_cost = 0.0025 # same scale as above
#parallel_tuple_cost = 0.1 # same scale as above
#parallel_setup_cost = 1000.0 # same scale as above
#jit_above_cost = 100000 # perform JIT compilation if available
# and query more expensive than this;
# -1 disables
#jit_inline_above_cost = 500000 # inline small functions if query is
# more expensive than this; -1 disables
#jit_optimize_above_cost = 500000 # use expensive JIT optimizations if
# query is more expensive than this;
# -1 disables
#min_parallel_table_scan_size = 8MB
#min_parallel_index_scan_size = 512kB
#effective_cache_size = 4GB
# - Genetic Query Optimizer -
#geqo = on
#geqo_threshold = 12
#geqo_effort = 5 # range 1-10
#geqo_pool_size = 0 # selects default based on effort
#geqo_generations = 0 # selects default based on effort
#geqo_selection_bias = 2.0 # range 1.5-2.0
#geqo_seed = 0.0 # range 0.0-1.0
# - Other Planner Options -
#default_statistics_target = 100 # range 1-10000
#constraint_exclusion = partition # on, off, or partition
#cursor_tuple_fraction = 0.1 # range 0.0-1.0
#from_collapse_limit = 8
#join_collapse_limit = 8 # 1 disables collapsing of explicit
# JOIN clauses
#force_parallel_mode = off
#jit = on # allow JIT compilation
#plan_cache_mode = auto # auto, force_generic_plan or
# force_custom_plan
#------------------------------------------------------------------------------
# REPORTING AND LOGGING
#------------------------------------------------------------------------------
# - Where to Log -
#log_destination = 'stderr' # Valid values are combinations of
# stderr, csvlog, syslog, and eventlog,
# depending on platform. csvlog
# requires logging_collector to be on.
# This is used when logging to stderr:
#logging_collector = off # Enable capturing of stderr and csvlog
# into log files. Required to be on for
# csvlogs.
# (change requires restart)
# These are only used if logging_collector is on:
#log_directory = 'log' # directory where log files are written,
# can be absolute or relative to PGDATA
#log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' # log file name pattern,
# can include strftime() escapes
#log_file_mode = 0600 # creation mode for log files,
# begin with 0 to use octal notation
#log_truncate_on_rotation = off # If on, an existing log file with the
# same name as the new log file will be
# truncated rather than appended to.
# But such truncation only occurs on
# time-driven rotation, not on restarts
# or size-driven rotation. Default is
# off, meaning append to existing files
# in all cases.
#log_rotation_age = 1d # Automatic rotation of logfiles will
# happen after that time. 0 disables.
#log_rotation_size = 10MB # Automatic rotation of logfiles will
# happen after that much log output.
# 0 disables.
# These are relevant when logging to syslog:
#syslog_facility = 'LOCAL0'
#syslog_ident = 'postgres'
#syslog_sequence_numbers = on
#syslog_split_messages = on
# This is only relevant when logging to eventlog (win32):
# (change requires restart)
#event_source = 'PostgreSQL'
# - When to Log -
#log_min_messages = warning # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# info
# notice
# warning
# error
# log
# fatal
# panic
#log_min_error_statement = error # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# info
# notice
# warning
# error
# log
# fatal
# panic (effectively off)
#log_min_duration_statement = -1 # logs statements and their durations
# according to log_statement_sample_rate. -1 is disabled,
# 0 logs all statement, > 0 logs only statements running at
# least this number of milliseconds.
#log_statement_sample_rate = 1 # Fraction of logged statements over
# log_min_duration_statement. 1.0 logs all statements,
# 0 never logs.
# - What to Log -
#debug_print_parse = off
#debug_print_rewritten = off
#debug_print_plan = off
#debug_pretty_print = on
#log_checkpoints = off
#log_connections = off
#log_disconnections = off
#log_duration = off
#log_error_verbosity = default # terse, default, or verbose messages
#log_hostname = off
#log_line_prefix = '%m [%p] ' # special values:
# %a = application name
# %u = user name
# %d = database name
# %r = remote host and port
# %h = remote host
# %p = process ID
# %t = timestamp without milliseconds
# %m = timestamp with milliseconds
# %n = timestamp with milliseconds (as a Unix epoch)
# %i = command tag
# %e = SQL state
# %c = session ID
# %l = session line number
# %s = session start timestamp
# %v = virtual transaction ID
# %x = transaction ID (0 if none)
# %q = stop here in non-session
# processes
# %% = '%'
# e.g. '<%u%%%d> '
#log_lock_waits = off # log lock waits >= deadlock_timeout
#log_statement = 'none' # none, ddl, mod, all
#log_replication_commands = off
#log_temp_files = -1 # log temporary files equal or larger
# than the specified size in kilobytes;
# -1 disables, 0 logs all temp files
#log_timezone = 'GMT'
#------------------------------------------------------------------------------
# PROCESS TITLE
#------------------------------------------------------------------------------
#cluster_name = '' # added to process titles if nonempty
# (change requires restart)
#update_process_title = on
#------------------------------------------------------------------------------
# STATISTICS
#------------------------------------------------------------------------------
# - Query and Index Statistics Collector -
#track_activities = on
#track_counts = on
#track_io_timing = off
#track_functions = none # none, pl, all
#track_activity_query_size = 1024 # (change requires restart)
#stats_temp_directory = 'pg_stat_tmp'
# - Monitoring -
#log_parser_stats = off
#log_planner_stats = off
#log_executor_stats = off
#log_statement_stats = off
#------------------------------------------------------------------------------
# AUTOVACUUM
#------------------------------------------------------------------------------
#autovacuum = on # Enable autovacuum subprocess? 'on'
# requires track_counts to also be on.
#log_autovacuum_min_duration = -1 # -1 disables, 0 logs all actions and
# their durations, > 0 logs only
# actions running at least this number
# of milliseconds.
#autovacuum_max_workers = 3 # max number of autovacuum subprocesses
# (change requires restart)
#autovacuum_naptime = 1min # time between autovacuum runs
#autovacuum_vacuum_threshold = 50 # min number of row updates before
# vacuum
#autovacuum_analyze_threshold = 50 # min number of row updates before
# analyze
#autovacuum_vacuum_scale_factor = 0.2 # fraction of table size before vacuum
#autovacuum_analyze_scale_factor = 0.1 # fraction of table size before analyze
#autovacuum_freeze_max_age = 200000000 # maximum XID age before forced vacuum
# (change requires restart)
#autovacuum_multixact_freeze_max_age = 400000000 # maximum multixact age
# before forced vacuum
# (change requires restart)
#autovacuum_vacuum_cost_delay = 2ms # default vacuum cost delay for
# autovacuum, in milliseconds;
# -1 means use vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for
# autovacuum, -1 means use
# vacuum_cost_limit
#------------------------------------------------------------------------------
# CLIENT CONNECTION DEFAULTS
#------------------------------------------------------------------------------
# - Statement Behavior -
#client_min_messages = notice # values in order of decreasing detail:
# debug5
# debug4
# debug3
# debug2
# debug1
# log
# notice
# warning
# error
#search_path = '"$user", public' # schema names
#row_security = on
#default_tablespace = '' # a tablespace name, '' uses the default
#temp_tablespaces = '' # a list of tablespace names, '' uses
# only default tablespace
#check_function_bodies = on
#default_transaction_isolation = 'read committed'
#default_transaction_read_only = off
#default_transaction_deferrable = off
#session_replication_role = 'origin'
#statement_timeout = 0 # in milliseconds, 0 is disabled
#lock_timeout = 0 # in milliseconds, 0 is disabled
#idle_in_transaction_session_timeout = 0 # in milliseconds, 0 is disabled
#vacuum_freeze_min_age = 50000000
#vacuum_freeze_table_age = 150000000
#vacuum_multixact_freeze_min_age = 5000000
#vacuum_multixact_freeze_table_age = 150000000
#vacuum_cleanup_index_scale_factor = 0.1 # fraction of total number of tuples
# before index cleanup, 0 always performs
# index cleanup
#bytea_output = 'hex' # hex, escape
#xmlbinary = 'base64'
#xmloption = 'content'
#gin_fuzzy_search_limit = 0
#gin_pending_list_limit = 4MB
# - Locale and Formatting -
#datestyle = 'iso, mdy'
#intervalstyle = 'postgres'
#timezone = 'GMT'
#timezone_abbreviations = 'Default' # Select the set of available time zone
# abbreviations. Currently, there are
# Default
# Australia (historical usage)
# India
# You can create your own file in
# share/timezonesets/.
#extra_float_digits = 1 # min -15, max 3; any value >0 actually
# selects precise output mode
#client_encoding = sql_ascii # actually, defaults to database
# encoding
# These settings are initialized by initdb, but they can be changed.
#lc_messages = 'C' # locale for system error message
# strings
#lc_monetary = 'C' # locale for monetary formatting
#lc_numeric = 'C' # locale for number formatting
#lc_time = 'C' # locale for time formatting
# default configuration for text search
#default_text_search_config = 'pg_catalog.simple'
# - Shared Library Preloading -
#shared_preload_libraries = '' # (change requires restart)
#local_preload_libraries = ''
#session_preload_libraries = ''
#jit_provider = 'llvmjit' # JIT library to use
# - Other Defaults -
#dynamic_library_path = '$libdir'
#------------------------------------------------------------------------------
# LOCK MANAGEMENT
#------------------------------------------------------------------------------
#deadlock_timeout = 1s
#max_locks_per_transaction = 64 # min 10
# (change requires restart)
#max_pred_locks_per_transaction = 64 # min 10
# (change requires restart)
#max_pred_locks_per_relation = -2 # negative values mean
# (max_pred_locks_per_transaction
# / -max_pred_locks_per_relation) - 1
#max_pred_locks_per_page = 2 # min 0
#------------------------------------------------------------------------------
# VERSION AND PLATFORM COMPATIBILITY
#------------------------------------------------------------------------------
# - Previous PostgreSQL Versions -
#array_nulls = on
#backslash_quote = safe_encoding # on, off, or safe_encoding
#escape_string_warning = on
#lo_compat_privileges = off
#operator_precedence_warning = off
#quote_all_identifiers = off
#standard_conforming_strings = on
#synchronize_seqscans = on
# - Other Platforms and Clients -
#transform_null_equals = off
#------------------------------------------------------------------------------
# ERROR HANDLING
#------------------------------------------------------------------------------
#exit_on_error = off # terminate session on any error?
#restart_after_crash = on # reinitialize after backend crash?
#data_sync_retry = off # retry or panic on failure to fsync
# data?
# (change requires restart)
#------------------------------------------------------------------------------
# CONFIG FILE INCLUDES
#------------------------------------------------------------------------------
# These options allow settings to be loaded from files other than the
# default postgresql.conf.
#include_dir = 'conf.d' # include files ending in '.conf' from
# directory 'conf.d'
#include_if_exists = 'exists.conf' # include file only if it exists
#include = 'special.conf' # include file
#------------------------------------------------------------------------------
# CUSTOMIZED OPTIONS
#------------------------------------------------------------------------------
# Add settings for extensions hereSelleks, et kõik toimiks, saab konteinerid käivitada käsuga docker-compose up -d. Või eraldi terminalis käsuga docker-compose up.
Nii, paketid on paigaldatud, andmebaas on käivitatud, nüüd tuleb need omavahel siduda. Selleks tuleb projekti juurkausta lisada fail ormconfig.js järgmise sisuga:
ormconfig.js
const process = require('process');
const username = process.env.POSTGRES_USER || "postgres";
const password = process.env.POSTGRES_PASSWORD || "example";
module.exports = {
"type": "postgres",
"host": "localhost",
"port": 5432,
username,
password,
"database": "postgres",
"synchronize": true,
"dropSchema": false,
"logging": true,
"entities": [__dirname + "/src/**/*.entity.ts", __dirname + "/dist/**/*.entity.js"],
"migrations": ["migrations/**/*.ts"],
"subscribers": ["subscriber/**/*.ts", "dist/subscriber/**/.js"],
"cli": {
"entitiesDir": "src",
"migrationsDir": "migrations",
"subscribersDir": "subscriber"
}
}
See konfiguratsioon kasutatakse typeormi CLI jaoks.
Vahetame selle konfigureeringu üle detailsemalt. Ridade 3 ja 4 puhul saame kasutajanime ja parooli keskkonnamuutujatest. See on mugav, kui teil on mitu keskkonda (dev, stage, prod jne). Vaikimisi on kasutajanimi postgres, parool — example. Ülejäänud konfigureerimine on triviaalne, seega peatume ainult kõige huvitavamate parameetrite juures:
- synchronize — määrab, kas andmebaasi skeem luuakse automaatselt rakenduse käivitamise ajal. Olge selle valiku osas ettevaatlik ja ärge kasutage seda tootmises, vastasel juhul võite andmed kaotada. See valik on mugav arendamisel ja rakenduse silumisel. Alternatiivina võite kasutada käsku
schema:syncCLI TypeORM-ist. - dropSchema — tühjendab skeemi iga kord, kui ühendus luuakse. Nagu eelmist, tuleks ka seda valikut kasutada ainult arendamise ja rakenduse silumise ajal.
- entities — nimed, mille kaudu otsitakse mudelite kirjeldusi. Pange tähele, et toetatakse mustri järgi otsimist.
- cli.entitiesDir — kaust, kuhu vaikimisi peaksid CLI TypeORM-i kaudu loodud mudelid jääma.
Kuna saaksime kasutada kõiki TypeORMi võimalusi meie Nest rakenduses, tuleb importida moodul TypeOrmModule ühes AppModule. See tähendab, et teie AppModule välja järgmine:
app.module.ts
import { Module } from '@nestjs/common';
import { AppController } from './app.controller';
import { AppService } from './app.service';
import { TypeOrmModule } from '@nestjs/typeorm';
import * as process from "process";
const username = process.env.POSTGRES_USER || 'postgres';
const password = process.env.POSTGRES_PASSWORD || 'example';
@Module({
imports: [
TypeOrmModule.forRoot({
type: 'postgres',
host: 'localhost',
port: 5432,
username,
password,
database: 'postgres',
entities: [__dirname + '/**/*.entity{.ts,.js}'],
synchronize: true,
}),
],
controllers: [AppController],
providers: [AppService],
})
export class AppModule {}Nagu olete märganud, edastatakse meetodi forRoot ka sama konfiguratsioon andmebaasiga töötamiseks, mis on failis ormconfig.ts
On jäänud viimane lihv — lisada mõned ülesanded TypeORMi jaoks package.json-sse. Asi on selles, et CLI on kirjutatud javascriptis ja töötab nodejs keskkonnas. Kuid kõik meie mudelid ja migreerimised kirjutatakse typescriptis. Seetõttu on vajalik meie migreerimiste ja mudelite transpileerimine enne CLI kasutamist. Selleks vajame paketti ts-node:
yarn add -D ts-node
Pärast seda lisame vajalikud käsud package.json-sse:
"typeorm": "ts-node -r tsconfig-paths/register ./node_modules/typeorm/cli.js",
"migration:generate": "yarn run typeorm migration:generate -n",
"migration:create": "yarn run typeorm migration:create -n",
"migration:run": "yarn run typeorm migration:run"Первая команда, typeorm, добавляет обертку в виде ts-node для запуска cli TypeORM. Остальные команды — это удобные сокращения, которыми вы как разработчик будете пользоваться практически каждый день:
migration:generate — создание миграции на основе изменений в ваших моделях.
migration:create — создание пустой миграции.
migration:run — запуск миграций.
Ну теперь точно все, мы добавили необходимые пакеты, сконфигурировали приложение для работы с базой как с cli, так и с самого приложения а также запустили СУБД. Пришло время добавить логику в наше приложение.
Установка пакетов для создания CRUD
Kasutades ainult Nest'i, on võimalik luua API, mis võimaldab luua, lugeda, uuendada ja kustutada objekti. Selline lahendus on maksimaalselt paindlik, kuid mõningatel juhtudel liiga keeruline. Näiteks, kui teil on vaja kiiresti prototüüpida, võib sageli paindlikkusest loobuda arenduse kiirusel. Paljud raamistikud pakuvad funktsionaalsust CRUD genereerimiseks, lähtudes teatud objekti andmemudelist. Ja Nest ei ole erand! Selle funktsionaalsuse pakub pakett . Selle võimalused on väga huvitavad:
- lihtne installimine ja seadistamine;
- sõltumatus andmebaasitarkvarast;
- võimas päringute keel, mis võimaldab filtreerimist, lehekestamist, sorteerimist, seoste ja sisemiste objektide laadimist, vahemällu salvestamist jne;
- pakett päringute koostamiseks front-end'is;
- lihtne kontrolleri meetodite ülekirjutamine;
- väike konfigureerimine;
- swagger dokumentatsiooni tugi.
Funktsionaalsus on jagatud mitmeks paketiks:
- — baaspakett, mis pakub dekoratsiooni () marsruutide genereerimiseks, seadistamiseks ja valideerimiseks;
- — pakett, mis pakub päringute koosturit/parsjat frontendi poole kasutamiseks;
- — пакет для интеграции с TypeORM, предоставляющий базовый сервис TypeOrmCrudService с CRUD методами работы с сущностями в БД.
В данном руководстве нам понадобятся пакеты jsx/crud и jsx/crud-typeorm. Для начала, поставим их
yarn add @nestjsx/crud class-transformer class-validatorPakettide ja в данном приложении требуются для декларативного описания правил трансформирования экземпляров моделей и валидации входящих запросов соответственно. Данные пакеты от одного автора, поэтому интерфейсы схожи.
Непосредственная реализация CRUD
В качестве примера модели мы возьмем список пользователей. У пользователей будут следующие поля: id, username, displayName, email. id — автоинкрементное поле, email ja username — уникальные поля. Все просто! Осталось воплотить нашу задумку в виде Nest приложения.
Для начала необходимо создать модуль users, который будет отвечать за работу с пользователями. Воспользуемся cli от NestJS, и в корневой директории нашего проекта выполним команду nest g module users.
nest g module users
dmitrii@dmitrii-HP-ZBook-17-G3:~/projects/nest-rest git:(master*)$ nest g module users
CREATE /src/users/users.module.ts (82 bytes)
UPDATE /src/app.module.ts (312 bytes)Selles moodulis loome kausta entities, kuhu paigutame selle mooduli mudelid. Eelkõige lisame siia faili user.entity.ts, mis sisaldab kasutajate mudeli kirjeldust:
user.entity.ts
import { Column, Entity, PrimaryGeneratedColumn } from 'typeorm';
@Entity()
export class User {
@PrimaryGeneratedColumn()
id: string;
@Column({unique: true})
email: string;
@Column({unique: true})
username: string;
@Column({nullable: true})
displayName: string;
}Kuna meie rakendus peab selle mudeli «nägema», tuleb moodulisse UsersModule importida TypeOrmModule järgnevate sisu:
users.module.ts
import { Module } from '@nestjs/common';
import { UsersController } from './controllers/users/users.controller';
import { UsersService } from './services/users/users.service';
import { TypeOrmModule } from '@nestjs/typeorm';
import { User } from './entities/user.entity';
@Module({
controllers: [UsersController],
providers: [UsersService],
imports: [
TypeOrmModule.forFeature([User])
]
})
export class UsersModule {}Ehk, siin me impordime TypeOrmModule, kus meetodi parameetrina forFeature märkime loetelu mudelitest, mis kuuluvad sellesse moodulisse.
Jäänud on luua vastav entiteet andmebaasis. Selleks on migration'ide mehhanism. Et luua migratsioon mudelite muudatustest, tuleb täita käsk npm run migration:generate -- CreateUserTable:
Spoilertitle
$ npm run migration:generate -- CreateUserTable
Migratsioon /home/dmitrii/projects/nest-rest/migrations/1563346135367-CreateUserTable.ts on edukalt loodud.
Valmis 1.96s.Me ei pidanud migratsiooni käsitsi kirjutama, kõik toimus maagiliselt. Kas see pole imeline! Kuid see pole veel kõik. Vaatame loodud migratsioonifaili:
1563346135367-CreateUserTable.ts
import {MigrationInterface, QueryRunner} from "typeorm";
export class CreateUserTable1563346816726 implements MigrationInterface {
public async up(queryRunner: QueryRunner): Promise {
await queryRunner.query(`CREATE TABLE "user" ("id" SERIAL NOT NULL, "email" character varying NOT NULL, "username" character varying NOT NULL, "displayName" character varying, CONSTRAINT "UQ_e12875dfb3b1d92d7d7c5377e22" UNIQUE ("email"), CONSTRAINT "UQ_78a916df40e02a9deb1c4b75edb" UNIQUE ("username"), CONSTRAINT "PK_cace4a159ff9f2512dd42373760" PRIMARY KEY ("id"))`);
}
public async down(queryRunner: QueryRunner): Promise {
await queryRunner.query(`DROP TABLE "user"`);
}
}Nagu märgata, genereeriti automaatselt mitte ainult migratsiooni käivitamise meetod, vaid ka selle tagasivõtmise meetod. Fantastiline!
Jäänud on ainult selle migratsiooni pealekandmine. Seda saab teha järgmise käsuga:
npm run migration:run.Kõik, nüüd on skeemi muudatused andmebaasi kantud.
Edasi loome teenuse, mis vastutab kasutajatega töötamise eest ja pärime selle TypeOrmCrudService. Vanemkonstruktorile tuleb edastada huvipakkuva entiteedi repo, meie puhul Kasutaja repo.
users.service.ts
import { Injectable } from '@nestjs/common';
import { TypeOrmCrudService } from '@nestjsx/crud-typeorm';
import { User } from '../../entities/user.entity';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
@Injectable()
export class UsersService extends TypeOrmCrudService{
constructor(@InjectRepository(User) usersRepository: Repository){
super(usersRepository);
}
}Seda teenust vajame kontrollis. users. Kontrolli loomiseks sisestage käsureale nest g controller users/controllers/users
nest g controller users/controllers/users
dmitrii@dmitrii-HP-ZBook-17-G3:~/projects/nest-rest git:(master*)$ nest g controller users/controllers/users
CREATE /src/users/controllers/users/users.controller.spec.ts (486 bytes)
CREATE /src/users/controllers/users/users.controller.ts (99 bytes)
UPDATE /src/users/users.module.ts (188 bytes)Avame selle kontrolli ja redigeerime seda, et lisada natuke võlu. jsx/crud. Klassile UsersController lisame järgmise kujuga dekoratori:
@Crud({
model: {
type: User
}
}) — see on dekorator, mis lisab kontrollile vajalikud meetodid mudeliga töötamiseks. Mudeli tüüp määratakse dekoratori konfiguratsiooni väljas model.type teatavasse konfiguratsiooniväli.
Teiseks sammuks on vajalik rakendada liidest CrudController. „Kogu“ kontrollikoodi näeb välja järgmiselt:
import { Controller } from '@nestjs/common';
import { Crud, CrudController } from '@nestjsx/crud';
import { User } from '../../entities/user.entity';
import { UsersService } from '../../services/users/users.service';
@Crud({
model: {
type: User
}
})
@Controller('users')
export class UsersController implements CrudController{
constructor(public service: UsersService){}
}Ja see on kõik! Nüüd toetab kontrollija kõiki mudeli operatsioone! Ei usu? Proovime meie rakendust praktikas!
TestMace'is päringute skripti loomine
Meie teenuse testimiseks kasutame API-dega töötamiseks IDE-d. . Miks TestMace? Võrreldes sarnaste toodetega on tal järgmised eelised:
- tõhus töö muutujatega. Praegu on olemas mitmeid muutujate tüüpe, millest igaühel on oma roll: sisseehitatud muutujad, dünaamilised muutujad, keskkonnamuutujad. Iga muutuja kuulub mõnele sõlmele, toetades pärimise mehhanismi;
- lihtne skriptide loomine ilma programmeerimiseta. Sellest räägime allpool;
- inimesele arusaadav formaat, mis võimaldab projekti salvestada versioonihaldussüsteemides;
- automaatne täiendamine, süntaksi rõhutamine, muutuja väärtuste rõhutamine;
- API toe kirjeldamine koos Swaggerist impordi võimalusega.
Käivitame meie serveri käsuga npm start ja proovime pääseda juurde kasutajate nimekirjale. Kasutajate nimekirja, lähtudes meie kontrolleri konfiguratsioonist, saab saada url-ilt localhost:3000/users. Teeme päringu sellele url-ile.
Pärast TestMace'i käivitamist näete sellist liidest:
Vasakul üleval on projektide puu, mille juure sõlm on . Proovime luua esimese päringu kasutajate nimekirja saamiseks. Selleks loome sõlme. Seda teeme Project sõlme kontekstimenüüs Lisa sõlm -> RequestStep.
Ala URL sisestage localhost:3000/users ja tehke päring. Saame 200 koodi tühja massiiviga vastuse kehas. See on mõistetav, me pole veel kedagi lisanud.
Loome stsenaariumi, mis sisaldab järgmisi samme:
- kasutaja loomine;
- päring id järgi hiljuti loodud kasutajale;
- kustutamine id järgi kasutajast, mis loodi 1. sammus.
Nii et alustame. Mugavuse huvides loome sõlme tüüpi . Sisuliselt on see lihtsalt kaust, kuhu salvestame kogu stsenaariumi. Folderi sõlme loomiseks tuleb Project sõlme kontekstimenüüs valida Lisa sõlm -> Folder. Nimeks paneme sõlme check-create. Node'i sees check-create loome meie esimese kasutaja loomise päringu. Nimetame just loodud node'i create-user. See tähendab, et hetkel näeb node'ite hieraarhia välja järgmine:
Liigume avatud create-user node'i vahekaardile. Sisestame päringu järgmised parameetrid:
- Päringu tüüp — POST
- URL — localhost:3000/users
- Body — JSON väärtusega
{"email": "user@user.com", "displayName": "New user", "username": "user"}
Teeme selle päringu. Meie rakendus ütleb, et salvestamine on loodud.
Noh, kontrollime seda fakti. Järgmiste sammude ajal, et kasutada loodud kasutaja id-d, on oluline see parameeter salvestada. Sel eesmärgil sobib hästi mehhanism . Vaadakem meie näite kaudu, kuidas nendega töötamine toimub. Node'i vastuse parsed vahekaardil tuleb id kontekstimenüüs valida Assign to variable. Dialooge aknas tuleb seadistada järgmised parameetrid:
- Sõlm — millises esivanemas luuakse dünaamiline muutuja. Valime check-create
- Variable name — selle muutuja nimi. Nimetame
userId.
Nii näeb dünaamilise muutuja loomise protsess välja:
Nüüd, kui me igakord selget päringut teeme, uuendatakse dünaamilise muutuja väärtust. Ja kuna dünaamilised muutujad toetavad hierarhilise pärandumise mehhanismi, on muutuja userId kättesaadav järglastel check-create mis tahes sügavuse sõlmedel.
Järgmises päringus on see muutuja meile kasulik. Nimelt, me küsime hiljuti loodud kasutajat. Järglasena sõlmest check-create loome päringu check-if exists argumenti url võrdne localhost:3000/users/${$dynamicVar.userId}. Konstruktsioon näeb välja nagu ${variable_name} see on muutuja väärtuse saamine. Kuna meil on dünaamiline muutuja, siis selle saamiseks on vaja pöörduda objekti $dynamicVar, st täielik pöördumine dünaamilisele muutujale userId näeb välja järgmiselt ${$dynamicVar.userId}. Teeme päringu ja veendume, et andmed küsitakse õigesti.
Viimane puudus on teha kustutuspäring. See on vajalik mitte ainult kustutamise töö kontrollimiseks, vaid ka, nii öelda, oma jälgede likvideerimiseks andmebaasis, kuna emaili ja kasutajanimi on ainulaadsed. Nii et sõlmes check-create loome kustutuspäringu delete-user järgmiste parameetritega
- Päringu tüüp — DELETE
- URL —
localhost:3000/users/${$dynamicVar.userId}
Käivitame. Ootame. Nautime tulemust.)
Nüüd saame igal ajal selle skripti täielikult käivitada. Skripti käivitamiseks tuleb kontekstimenüüst valida check-create sõlm punkt Run.
Sõlmed skriptis täidetakse järjestikku
Selle skripti võid salvestada oma projekti, tehes Fail -> Salvesta projekt.
Kokkuvõte
Selle artikli formaati ei mahtunud kõik kasulikud tööriistad. Mis puudutab peamist süüdlast — paketti jsx/crud — jäävad varjatuks järgmised teemad:
- kohandatud valideerimine ja mudelite transformatsioon;
- võimas päringute keel ja selle mugav kasutamine front-end'is;
- meetodite üledefineerimine ja uute lisamine crud-kontrollerites;
- swaggeri tugi;
- vahemälu haldamine.
Kuid isegi artiklis kirjeldatu piisab, et mõista, et isegi selline ettevõtte raamistik nagu NestJS omab tööriistu rakenduste kiireks prototüüpimiseks. Ja selline suurepärane IDE nagu aitab hoida soovitud rütmi.
Antud artikli lähtekood, koos projektiga , on salvestatud repos . Projekti avamiseks piisab, kui teed rakenduses Fail -> Ava projekt.
Allikas: habr.com
