Trenutno je REST API postal standard za razvoj spletnih aplikacij, ki omogoča razdelitev razvoja na neodvisne dele. Za uporabniški vmesnik se trenutno uporabljajo različni priljubljeni okviri, kot so Angular, React, Vue in drugi. Zaledni razvijalci lahko izbirajo med široko paleto jezikov in ogrodij. Danes bi rad govoril o takšnem okviru, kot je . Prišli smo Aktivno ga uporabljamo za interne projekte. Uporaba gnezda in paketa , bomo ustvarili preprosto aplikacijo CRUD.
Zakaj NestJS
Nedavno se je v skupnosti JavaScript pojavilo precej zalednih ogrodij. In če v smislu funkcionalnosti zagotavljajo podobne zmogljivosti kot Nest, potem v eni stvari zagotovo zmaga - to je arhitektura. Naslednje funkcije NestJS vam omogočajo ustvarjanje industrijskih aplikacij in razširitev razvoja na velike ekipe:
- z uporabo TypeScripta kot glavnega razvojnega jezika. Čeprav NestJS podpira JavaScript, nekatere funkcije morda ne bodo delovale, zlasti če govorimo o paketih tretjih oseb;
- prisotnost vsebnika DI, ki vam omogoča ustvarjanje ohlapno povezanih komponent;
- Funkcionalnost samega ogrodja je razdeljena na neodvisne zamenljive komponente. Na primer, pod pokrovom kot okvir se lahko uporablja kot In , za delo z zbirko podatkov, gnezdo takoj po namestitvi zagotavlja vezave na , , ;
- NestJS je neodvisen od platforme in podpira REST, GraphQL, Websockets, gRPC itd.
Sam okvir se zgleduje po ogrodju frontend Angular in ima konceptualno veliko skupnega z njim.
Namestitev NestJS in uvedba projekta
Nest vsebuje paket /cli, ki vam omogoča hitro namestitev osnovnega aplikacijskega ogrodja. Namestimo ta paket globalno:
npm install --global @nest/cliPo namestitvi bomo generirali osnovno ogrodje naše aplikacije z imenom gnezdo-rest. To se naredi z ukazom nest new nest-rest.
gnezdo novo gnezdo-počitek
dmitrii@dmitrii-HP-ZBook-17-G3:~/projects $ nest new nest-rest
We will scaffold your app in a few seconds..
CREATE /nest-rest/.prettierrc (51 bytes)
CREATE /nest-rest/README.md (3370 bytes)
CREATE /nest-rest/nest-cli.json (84 bytes)
CREATE /nest-rest/nodemon-debug.json (163 bytes)
CREATE /nest-rest/nodemon.json (67 bytes)
CREATE /nest-rest/package.json (1805 bytes)
CREATE /nest-rest/tsconfig.build.json (97 bytes)
CREATE /nest-rest/tsconfig.json (325 bytes)
CREATE /nest-rest/tslint.json (426 bytes)
CREATE /nest-rest/src/app.controller.spec.ts (617 bytes)
CREATE /nest-rest/src/app.controller.ts (274 bytes)
CREATE /nest-rest/src/app.module.ts (249 bytes)
CREATE /nest-rest/src/app.service.ts (142 bytes)
CREATE /nest-rest/src/main.ts (208 bytes)
CREATE /nest-rest/test/app.e2e-spec.ts (561 bytes)
CREATE /nest-rest/test/jest-e2e.json (183 bytes)
? Which package manager would you ️ to use? yarn
Installation in progress...
Successfully created project nest-rest
Get started with the following commands:
$ cd nest-rest
$ yarn run start
Thanks for installing Nest
Please consider donating to our open collective
to help us maintain this package.
Donate: https://opencollective.com/nestZa upravitelja paketov bomo izbrali yarn.
Na tej točki lahko zaženete strežnik z ukazom npm start in grem na naslov lahko vidite glavno stran. Vendar nismo zato tukaj zbrani in gremo naprej.
Nastavitev dela z bazo podatkov
Za ta članek sem izbral PostrgreSQL kot DBMS. O okusih ni spora, po mojem mnenju je to najbolj zrel DBMS, ki ima vse potrebne zmogljivosti. Kot že rečeno, Nest omogoča integracijo z različnimi paketi za delo z bazami podatkov. Ker Ker je moja izbira padla na PostgreSQL, bi bilo logično, da kot ORM izberem TypeORM. Namestimo potrebne pakete za integracijo z bazo podatkov:
yarn add typeorm @nestjs/typeorm pg
Za kaj potrebujemo posamezen paket:
- typeorm - paket neposredno iz samega ORM;
- @nestjs/typeorm - paket TypeORM za NestJS. Doda module za uvoz v module projekta, kot tudi nabor pomožnih okrasiteljev;
- pg - gonilnik za delo s PostgreSQL.
V redu, paketi so nameščeni, zdaj morate zagnati samo bazo podatkov. Za razmestitev baze podatkov bom uporabil docker-compose.yml z naslednjo vsebino:
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:
- 8080:8080Kot lahko vidite, ta datoteka konfigurira zagon 2 vsebnikov:
- db je vsebnik, ki neposredno vsebuje bazo podatkov. V našem primeru je uporabljena različica postgresql 11.2;
- skrbnik—upravitelj baze podatkov. Zagotavlja spletni vmesnik za ogled in upravljanje baze podatkov.
Za delo s povezavami tcp sem dodal naslednjo konfiguracijo.
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 hereTo je vse, vsebnike lahko zaženete z ukazom docker-compose up -d. Ali v ločeni konzoli z ukazom docker-compose up.
Paketi so torej nameščeni, baza podatkov je zagnana, ostane le še, da jih spravimo medsebojne prijatelje. Če želite to narediti, morate v koren projekta dodati naslednjo datoteko: ormconfig.js:
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"
}
}
Ta konfiguracija bo uporabljena za cli typeorm.
Oglejmo si to konfiguracijo podrobneje. V 3. in 4. vrstici dobimo uporabniško ime in geslo iz spremenljivk okolja. To je priročno, če imate več okolij (dev, stage, prod itd.). Privzeto je uporabniško ime postgres, geslo pa example. Preostali del konfiguracije je trivialen, zato se bomo osredotočili le na najbolj zanimive parametre:
- synchronize - Označuje, ali naj se shema baze podatkov samodejno ustvari ob zagonu aplikacije. Bodite previdni pri tej možnosti in je ne uporabljajte v proizvodnji, sicer boste izgubili podatke. Ta možnost je priročna pri razvoju in odpravljanju napak v aplikaciji. Kot alternativo tej možnosti lahko uporabite ukaz
schema:synciz CLI TypeORM. - dropSchema - ponastavi shemo vsakič, ko je vzpostavljena povezava. Tako kot prejšnjo je treba tudi to možnost uporabljati samo med razvojem in odpravljanjem napak v aplikaciji.
- entitete - po katerih poteh iskati opise modelov. Upoštevajte, da je podprto iskanje po maski.
- cli.entitiesDir je imenik, kjer naj bodo privzeto shranjeni modeli, ustvarjeni iz TypeORM CLI.
Da bomo lahko uporabljali vse funkcije TypeORM v naši aplikaciji Nest, moramo uvoziti modul TypeOrmModule в AppModule. Tisti. tvoje AppModule bo videti tako:
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 {}Kot ste morda opazili, metoda forRoot prenese se enaka konfiguracija za delo z bazo kot v datoteki ormconfig.ts
Ostaja še zadnji dotik - dodajte več nalog za delo s TypeORM v package.json. Dejstvo je, da je CLI napisan v javascriptu in deluje v okolju nodejs. Vendar bodo vsi naši modeli in migracije napisani v tipkopisu. Zato je treba pred uporabo CLI prevesti naše migracije in modele. Za to potrebujemo paket ts-node:
yarn add -D ts-node
Po tem dodajte potrebne ukaze v package.json:
"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"Prvi ukaz, typeorm, doda ovoj ts-node za zagon klica TypeORM. Preostali ukazi so priročne bližnjice, ki jih boste kot razvijalec uporabljali skoraj vsak dan:
migration:generate — ustvarjanje migracij na podlagi sprememb v vaših modelih.
migration:create — ustvarjanje prazne selitve.
migration:run — zagon migracij.
No, to je zdaj to, dodali smo potrebne pakete, konfigurirali aplikacijo za delo z bazo tako iz clija kot iz same aplikacije in zagnali tudi DBMS. Čas je, da naši aplikaciji dodamo logiko.
Namestitev paketov za ustvarjanje CRUD
Z uporabo samo Nesta lahko ustvarite API, ki vam omogoča ustvarjanje, branje, posodabljanje in brisanje entitete. Ta rešitev bo čim bolj prilagodljiva, vendar bo v nekaterih primerih odveč. Na primer, če morate hitro ustvariti prototip, lahko pogosto žrtvujete prilagodljivost za hitrost razvoja. Veliko ogrodij zagotavlja funkcionalnost za generiranje CRUD z opisom podatkovnega modela določene entitete. In Nest ni izjema! To funkcionalnost zagotavlja paket . Njegove zmogljivosti so zelo zanimive:
- enostavna namestitev in konfiguracija;
- neodvisnost DBMS;
- zmogljiv jezik poizvedb z možnostjo filtriranja, paginiranja, razvrščanja, nalaganja odnosov in ugnezdenih entitet, predpomnjenja itd.;
- paket za generiranje zahtev na front-endu;
- enostavno preglasitev metod krmilnika;
- majhna konfiguracija;
- podpora za bahavo dokumentacijo.
Funkcionalnost je razdeljena na več paketov:
- - osnovni paket, ki ga opremi dekorater () za ustvarjanje poti, konfiguracijo in validacijo;
- — paket, ki ponuja graditelj/razčlenjevalnik poizvedb za uporabo na sprednji strani;
- — paket za integracijo s TypeORM, ki zagotavlja osnovno storitev TypeOrmCrudService z metodami CRUD za delo z entitetami v bazi podatkov.
V tej vadnici bomo potrebovali pakete jsx/crud in jsx/crud-typeorm. Najprej jih postavimo
yarn add @nestjsx/crud class-transformer class-validatorPaketi и v tej aplikaciji so potrebni za deklarativni opis pravil za preoblikovanje instanc modela oziroma preverjanje veljavnosti dohodnih zahtev. Ti paketi so od istega avtorja, zato so vmesniki podobni.
Neposredna implementacija CRUD
Kot primer modela bomo vzeli seznam uporabnikov. Uporabniki bodo imeli naslednja polja: id, username, displayName, email. id - polje za samodejno povečevanje, email и username - edinstvena polja. Enostavno je! Ostaja le še uresničitev naše ideje v obliki aplikacije Nest.
Najprej morate ustvariti modul users, ki bo odgovoren za delo z uporabniki. Uporabimo cli iz NestJS in izvedimo ukaz v korenskem imeniku našega projekta nest g module users.
uporabniki modula nest g
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)V tem modulu bomo dodali mapo entitet, kjer bomo imeli modele tega modula. Tukaj še posebej dodamo datoteko user.entity.ts z opisom uporabniškega modela:
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;
}Da ta model "vidi" naša aplikacija, je potrebno v modulu UsersModule uvoz TypeOrmModule naslednjo vsebino:
uporabniki.modul.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 {}Se pravi, tukaj uvažamo TypeOrmModule, kjer kot parameter metode forFeature Navedemo seznam modelov, povezanih s tem modulom.
Vse, kar ostane, je ustvariti ustrezno entiteto v bazi podatkov. V te namene služi migracijski mehanizem. Če želite ustvariti selitev na podlagi sprememb v modelih, morate zagnati ukaz npm run migration:generate -- CreateUserTable:
naslov spojlerja
$ npm run migration:generate -- CreateUserTable
Migration /home/dmitrii/projects/nest-rest/migrations/1563346135367-CreateUserTable.ts has been generated successfully.
Done in 1.96s.Migracije nam ni bilo treba pisati ročno, vse se je zgodilo čarobno. Ali ni to čudež! Vendar to še ni vse. Oglejmo si ustvarjeno selitveno datoteko:
1563346135367-CreateUserTable.ts
import {MigrationInterface, QueryRunner} from "typeorm";
export class CreateUserTable1563346816726 implements MigrationInterface {
public async up(queryRunner: QueryRunner): Promise<any> {
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<any> {
await queryRunner.query(`DROP TABLE "user"`);
}
}Kot lahko vidite, ni bila samodejno ustvarjena le metoda za začetek selitve, ampak tudi metoda za njeno povrnitev. fantastično!
Vse, kar ostane, je uvesti to selitev. To naredite z naslednjim ukazom:
npm run migration:run.To je to, zdaj so se spremembe sheme preselile v bazo podatkov.
Nato bomo ustvarili storitev, ki bo odgovorna za delo z uporabniki in jo podedovala TypeOrmCrudService. Repozitorij interesne entitete je treba posredovati parametru nadrejenega konstruktorja, v našem primeru User repozitorij.
uporabniki.storitev.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<User>{
constructor(@InjectRepository(User) usersRepository: Repository<User>){
super(usersRepository);
}
}To storitev bomo potrebovali v krmilniku users. Če želite ustvariti krmilnik, vnesite v konzolo nest g controller users/controllers/users
nest g krmilnik uporabniki/krmilniki/uporabniki
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)Odprimo ta krmilnik in ga uredimo, da dodamo malo čarovnije jsx/crud. Na razred UsersController Dodajmo dekoraterja, kot je ta:
@Crud({
model: {
type: User
}
}) je dekorater, ki krmilniku doda potrebne metode za delo z modelom. V polju je navedena vrsta modela model.type konfiguracije dekoraterja.
Drugi korak je implementacija vmesnika CrudController<User>. "Sestavljena" koda krmilnika izgleda takole:
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<User>{
constructor(public service: UsersService){}
}In to je vse! Zdaj krmilnik podpira celoten niz operacij z modelom! ne verjameš? Preizkusimo našo aplikacijo v akciji!
Ustvarjanje skripta poizvedbe v TestMace
Za testiranje naše storitve bomo uporabili IDE za delo z API-jem . Zakaj TestMace? V primerjavi s podobnimi izdelki ima naslednje prednosti:
- zmogljivo delo s spremenljivkami. Trenutno obstaja več vrst spremenljivk, od katerih vsaka igra določeno vlogo: vgrajene spremenljivke, dinamične spremenljivke, spremenljivke okolja. Vsaka spremenljivka pripada vozlišču s podporo za mehanizem dedovanja;
- Preprosto ustvarite skripte brez programiranja. O tem bomo razpravljali v nadaljevanju;
- človeku berljiv format, ki omogoča shranjevanje projekta v sistemih za nadzor različic;
- samodokončanje, označevanje sintakse, označevanje vrednosti spremenljivke;
- Podpora za opis API-ja z možnostjo uvoza iz Swaggerja.
Zaženimo naš strežnik z ukazom npm start in poskusite dostopati do seznama uporabnikov. Seznam uporabnikov, sodeč po konfiguraciji našega krmilnika, lahko dobite na naslovu url localhost:3000/users. Pošljimo zahtevo na ta url.
Po zagonu TestMace lahko vidite vmesnik, kot je ta:
Zgoraj levo je drevo projekta s korenskim vozliščem . Poskusimo ustvariti prvo zahtevo za pridobitev seznama uporabnikov. Za to bomo ustvarili vozlišče To se naredi v kontekstnem meniju vozlišča Projekt Dodaj vozlišče -> RequestStep.
V polje URL prilepite localhost:3000/users in zaženite zahtevo. Prejeli bomo kodo 200 s praznim poljem v telesu odgovora. Razumljivo, nikogar še nismo dodali.
Ustvarimo skript, ki bo vključeval naslednje korake:
- ustvarjanje uporabnika;
- zahteva za ID novo ustvarjenega uporabnika;
- brisanje z ID-jem uporabnika, ustvarjenim v 1. koraku.
Torej, gremo. Za udobje ustvarimo vozlišče, kot je . V bistvu je to le mapa, v katero bomo shranili celoten skript. Če želite ustvariti vozlišče mape, v kontekstnem meniju vozlišča izberite Projekt Dodaj vozlišče -> Mapa. Pokličimo vozlišče preveri-ustvari. Znotraj vozlišča preveri-ustvari Ustvarimo prvo zahtevo za ustvarjanje uporabnika. Pokličimo novo ustvarjeno vozlišče ustvari uporabnika. To pomeni, da bo trenutno hierarhija vozlišč videti takole:
Pojdimo na odprti zavihek ustvari uporabnika vozlišče. V zahtevo vnesemo naslednje parametre:
- Vrsta zahteve - POST
- URL - localhost:3000/uporabniki
- Telo - JSON z vrednostjo
{"email": "[email protected]", "displayName": "New user", "username": "user"}
Izpolnimo to zahtevo. Naša aplikacija pravi, da je zapis ustvarjen.
No, preverimo to dejstvo. Za delo z ID-jem ustvarjenega uporabnika v naslednjih korakih je treba ta parameter shraniti. Mehanizem je kot nalašč za to. . Na našem primeru poglejmo, kako delati z njimi. V razčlenjenem zavihku odgovora poleg vozlišča id v kontekstnem meniju izberite element Dodeli spremenljivki. V pogovornem oknu morate nastaviti naslednje parametre:
- Node — v katerem od prednikov ustvariti dinamično spremenljivko. Izberimo preveri-ustvari
- Ime spremenljivke — ime te spremenljivke. Pokličimo
userId.
Postopek ustvarjanja dinamične spremenljivke je videti tako:
Zdaj bo ob vsaki izvedbi te poizvedbe vrednost dinamične spremenljivke posodobljena. In ker dinamične spremenljivke podpirajo mehanizem hierarhičnega dedovanja, spremenljivka userId bo na voljo v potomcih preveri-ustvari vozlišče katere koli ravni gnezdenja.
Ta spremenljivka nam bo koristila pri naslednji zahtevi. Zahtevali bomo namreč novo ustvarjenega uporabnika. Kot otrok vozlišča preveri-ustvari bomo ustvarili zahtevo preveri, če obstaja s parametrom url enako localhost:3000/users/${$dynamicVar.userId}. Ogled dizajna ${variable_name} to je pridobivanje vrednosti spremenljivke. Ker Imamo dinamično spremenljivko, zato morate za njeno pridobitev dostopati do objekta $dynamicVar, tj. popoln dostop do dinamične spremenljivke userId bo videti takole ${$dynamicVar.userId}. Izvedimo zahtevo in poskrbimo, da so zahtevani podatki pravilno.
Zadnji preostali korak je zahteva za izbris. Potrebujemo ga ne le za preverjanje delovanja izbrisa, ampak tako rekoč tudi za čiščenje baze podatkov, ker Polji za e-pošto in uporabniško ime sta edinstveni. Torej bomo v vozlišču za preverjanje in ustvarjanje ustvarili zahtevo za brisanje uporabnika z naslednjimi parametri
- Vrsta zahteve - IZBRIŠI
- URL -
localhost:3000/users/${$dynamicVar.userId}
Zaženimo. Čakamo. Uživamo v rezultatu)
No, zdaj lahko kadar koli zaženemo celoten skript. Za zagon skripta morate izbrati v kontekstnem meniju preveri-ustvari postavka vozlišča Run.
Vozlišča v skriptu se bodo izvajala eno za drugim
Ta skript lahko shranite v svoj projekt tako, da zaženete Datoteka -> Shrani projekt.
Zaključek
Vse funkcije uporabljenih orodij preprosto niso mogle ustrezati obliki tega članka. Glede glavnega krivca – paketa jsx/crud - naslednje teme ostajajo nepokrite:
- validacija in transformacija modelov po meri;
- zmogljiv poizvedovalni jezik in njegova priročna uporaba na sprednji strani;
- redefiniranje in dodajanje novih metod krmilnikom crud;
- bahata podpora;
- upravljanje predpomnjenja.
Vendar je že to, kar je opisano v članku, dovolj, da razumemo, da ima tudi takšno poslovno ogrodje, kot je NestJS, orodja za hitro izdelavo prototipov aplikacij. In tako kul IDE vam omogoča, da vzdržujete dani tempo.
Izvorna koda za ta članek, skupaj s projektom , ki je na voljo v skladišču . Odpreti projekt samo naredite to v aplikaciji Datoteka -> Odpri projekt.
Vir: www.habr.com