Обсуждение: [PATCH] psql: Allow connection string parameters as positional arguments
[PATCH] psql: Allow connection string parameters as positional arguments
От
Daymel Bonne Solís
Дата:
Hi hackers,
I'd like to propose a small enhancement to psql that improves usability when working with connection services and other libpq connection parameters.
Problem
Currently, when users try to use connection string parameters like service=myservice as positional arguments to psql, the behavior is confusing. For example:
psql service=production dbname=postgres -c "SELECT current_database()"
This fails with:
Password for user dbname=postgres:
psql: error: password authentication failed for user "dbname=postgres"
The issue is that psql interprets service=centraldb as the database name (first positional arg) and dbname=postgres as the username (second positional arg), treating them as literal strings rather than connection parameters.
Use Case
This is particularly inconvenient when working with pg_service.conf, where users define connection profiles but occasionally need to override specific parameters. Currently, the workaround requires quoting the entire connection string:
# Current workaround (verbose)
psql -d "service=centraldb dbname=postgres" -c "SELECT current_database()"
# Desired syntax (intuitive)
psql service=centraldb -d postgres -c "SELECT current_database()"
The proposed syntax is more intuitive and aligns with how other tools handle similar parameter overrides.
Solution
This patch modifies psql to recognize positional arguments containing = as connection string parameters. These are collected into a connection string that serves as the base for the connection. Explicit options (-d, -h, -p, -U) override corresponding values.
The implementation:
- Adds a connstring field to struct adhoc_opts
- Modifies parse_psql_options() to detect and collect key=value arguments
- Updates the connection logic to merge connstring with explicit options
Backward Compatibility
This change is fully backward compatible:
- Regular positional arguments (without =) continue to work as database name and username
- Database names containing = are rare and can still be specified via -d "db=name"
- All existing command-line patterns remain functional
Examples
# Use service with database override
psql service=production -d postgres
# Multiple connection parameters
psql host=localhost port=5433 sslmode=require -d mydb
# Mix key=value with regular positional arg
psql host=localhost port=5433 mydb
Testing
The patch includes a new TAP test file (t/002_connstring.pl) with 17 test cases covering:
- Basic key=value positional arguments
- Override behavior with -d flag
- Multiple key=value parameters
- Mixed key=value and regular positional arguments
- Parameter ordering variations
All existing psql tests continue to pass.
Patch attached.
Feedback welcome!
---
Best regards, Daymel Bonne
I'd like to propose a small enhancement to psql that improves usability when working with connection services and other libpq connection parameters.
Problem
Currently, when users try to use connection string parameters like service=myservice as positional arguments to psql, the behavior is confusing. For example:
psql service=production dbname=postgres -c "SELECT current_database()"
This fails with:
Password for user dbname=postgres:
psql: error: password authentication failed for user "dbname=postgres"
The issue is that psql interprets service=centraldb as the database name (first positional arg) and dbname=postgres as the username (second positional arg), treating them as literal strings rather than connection parameters.
Use Case
This is particularly inconvenient when working with pg_service.conf, where users define connection profiles but occasionally need to override specific parameters. Currently, the workaround requires quoting the entire connection string:
# Current workaround (verbose)
psql -d "service=centraldb dbname=postgres" -c "SELECT current_database()"
# Desired syntax (intuitive)
psql service=centraldb -d postgres -c "SELECT current_database()"
The proposed syntax is more intuitive and aligns with how other tools handle similar parameter overrides.
Solution
This patch modifies psql to recognize positional arguments containing = as connection string parameters. These are collected into a connection string that serves as the base for the connection. Explicit options (-d, -h, -p, -U) override corresponding values.
The implementation:
- Adds a connstring field to struct adhoc_opts
- Modifies parse_psql_options() to detect and collect key=value arguments
- Updates the connection logic to merge connstring with explicit options
Backward Compatibility
This change is fully backward compatible:
- Regular positional arguments (without =) continue to work as database name and username
- Database names containing = are rare and can still be specified via -d "db=name"
- All existing command-line patterns remain functional
Examples
# Use service with database override
psql service=production -d postgres
# Multiple connection parameters
psql host=localhost port=5433 sslmode=require -d mydb
# Mix key=value with regular positional arg
psql host=localhost port=5433 mydb
Testing
The patch includes a new TAP test file (t/002_connstring.pl) with 17 test cases covering:
- Basic key=value positional arguments
- Override behavior with -d flag
- Multiple key=value parameters
- Mixed key=value and regular positional arguments
- Parameter ordering variations
All existing psql tests continue to pass.
Patch attached.
Feedback welcome!
---
Best regards, Daymel Bonne