Development Specs

Message standardization

How should Errors/Warnings/Messages be formatted

• Only user derived variables should be bracketed, not GRASS derived variables. for example:

Yes: Creating raster map <%s>.  Pass 1 of 7 ...
No:  Creating <raster> map <%s>.  Pass [1] of [7] ...

• strings < >
  • e.g. Raster map <%s> not found
• numbers [ ]
  • e.g. Line [%d] deleted

? The [bracketed] parenthetical disrupts the flow of the phrase and doesn't help enhance clarity of meaning. IMHO, this reads better without [] brackets: "Line %d deleted." [] Brackets should be used when value is outside of the phrase: "Unknown line [%d]". --HB

Discussion:

Statistics [2007-04-11]:

symbol	number of code lines
<%s>	637
[%s]	690
'%s'	354
<%d>	12
[%d]	207
'%d'	3

Macros to be defined for C library

• MSG_RASTER_NOT_FOUND_IN_MAPSET - "Raster map <%s> not found in <%s>"
• MSG_CANNOT_OPEN_RASTER - "Failed opening raster map <%s>"
• MSG_CANNOT_OPEN_FILE - Cannot open file <%s>

Note: Problem with xgettext package. How to use macros to work with xgettext?

Standard messages sandbox

• First letter should be capitalized
• Use the present tense

(cannot instead of could not; better: unable to; even better: avoid the issue altogether by rewording like "File not found.")

• Avoid contractions (cannot instead of can't)
• Good sentence construction

("Cannot find input map <%s>" instead of "It could not be find input map <%s>"; possibly better: "Input map <%s> not found.")

• Be consistent with periods. Either end all phrases with a period or none. Without periods the translators save also some time

Complete sentences or all parts of a message with multiple sentences should end with periods. Short phrases should not. Punctuated events, such as errors, deserve a period. e.g. "Operation complete." Phrases which imply ongoing action look odd if missing an ellipse or any other form of punctuation. Phrase != Sentence. --HB

• Either all module descriptions should end with periods or not. As some are multi-sentence, and thus should end in a period for consistency within the message, so probably they all should end in one. Currently by my count 237 end with '.', 139 do not. In the multi-sentence case it may be posible to put the simple description in the module->label field and additional explanitory text into the ->description field.

• option and flag descriptions generally should not end in a period (more likely to be phrases than sentences). But they can suffer the same multi-sentence period problem as module descriptions. In this case splitting out additional text into a ->label, ->description split may help.

• Suspension points used to indicate some process is being done should be placed next to last word, without space. e.g. "Reading map..." instead of "Reading map ..."

--HB: FWIW & my 2c, 1) to me keeping the space before the ellipse looks better, is this a purely cosmetic choice or is there some style logic? [wikipedia article on the ellipse was cited on grass-dev, I would argue that refers to printed typeset text not monospace terminal text, is just one other guy's opinion, and I'm still not swayed] 2) these messages may be good candidates for G_verbose_message().

-- HB 2c more: (i.landsat.rgb example)

Processing <$i>...
Processing <$i> ...

The version with the space just looks better. The version without just looks wrong.

• Module descriptions should use all the same verbal tense. Currently some of them can be found in infinitive and others in present.

DB messages

db_open_database(), db_start_driver_open_database()

Unable to open database <%s> by driver <%s>

db_execute_immediate()

Unable to insert new record: %s

Unable to create table: %s

db_grant_on_table()

Unable to grant privileges on table <%s>

db_start_driver()

Unable to start driver <%s>

db_describe_table()

Unable to describe table <%s>

db_select_value()

Unable to select record from table <%s> (key %s, column %s)

db_fetch()

Unable to fetch data from table <%s>

db_create_index(), db_create_index2()

Unable to create index for table <%s>, key <%s>

db_copy_table(), db_copy_table_by_ints()

Unable to copy table <%s>

db_delete_table()

Unable to delete table <%s>

db_table_exists()

Unable to find table <%s> linked to vector map <%s>

db_get_column()

Column <%s> not found in table <%s>

General messages

G_legal_filename()

<%s> is an illegal file name

G_set_window()

Invalid graphics coordinates

Unable to set region

D_do_conversions()

Error calculating graphics-region conversions

G_tempfile()

Unable to open temporary file <%s>

G_get_projinfo()

Unable to get projection info of raster map

G_get_projunits()

Unable to get projection units of raster map

Raster messages

G_find_cell2()

Raster map <%s> not found

Raster map <%s> not found in the current mapset

Raster map <%s> not found in mapset <%s>

G_open_cell_old()

Unable to open raster map <%s>

G_open_cell_new()

Unable to create raster map <%s>

G_close_cell()

Unable to close raster map <%s>

G_get_cellhd()

Unable to read header of raster map <%s>

G_get_raster_row()

Unable to read raster map <%s> row %d

G_put_raster_row()

Failed writing raster map <%s> row %d

G_write_cats()

Unable to write category file for raster map <%s>

G_read_colors()

Unable to read color file of raster map <%s>

G_read_cats()

Unable to read category file of raster map <%s>

G_read_fp_range()

Unable to read fp range of raster map <%s>

G_read_range()

Unable to read range of raster map <%s>

Vector messages

G_find_vector2()

Vector map <%s> not found

Vector map <%s> not found in the current mapset

Vector map <%s> not found in mapset <%s>

Vect_open_old()

Unable to open vector map <%s>

Unable to open vector map <%s> at topology level %d

Vect_open_new()

Unable to create vector map <%s>

Vect_get_field(), Vect_get_dblink()

Database connection not defined for layer %d

Vect_get_area_centroid()

Area %d without centroid or Skipping area %d without centroid

Vect_open_old_head()

Unable to open header file of vector map <%s>

Vect_map_add_dblink()

Unable to add database link for vector map <%s>

Messages Discussion

• "Map <roads> in <user1>" or "Map <roads@user1>"
  • "Map <roads@user1>" preferred - ML
  • If the element was given on the command line, the user knows which mapset it came from, and the @mapset part is just extra noise. If the element is taken from the data (how? i.group?) where the user hasn't explicitly defined the map, then @mapset it appropriate. Also output maps are always created in the current mapset* so @mapset is redundant and should not be used for new maps. [* i.rectify, r.in.gdal, v.in.ogr are exceptions that can create maps in other mapsets or new locations] --HB

Proposed standard responses in bold.

• G_get_raster_row

"Unable to read raster map <%s> row %d"

Cannot get raster raster of input map
Cannot raster raster of input map
Cannot read raster row [%d]
can't read row in input elevation map
Could not read from <%s>
Could not read from <%s>, row=%d
Error getting input null cells
error reading hue data
Error reading 'hue' map
Error reading input
error reading intensity data
Error reading 'intensity' map
Error reading map %s
Error reading row of data
error reading saturation data
Error reading 'saturation' map
G_get_raster_row failed
reading map
Reading map
Reading row %d
read_row: error reading data
%s: Unable to read raster map [%s]
Unable to get row %d from raster map
Unable to get row %d from <%s>
Unable to read map raster row %d
Unable to read raster row.
Unable to read raster row %d
Unable to read row %i\n

• G_put_raster_row

"Failed writing raster map <%s> row %d"

Cannot write row to raster map
Cannot write to <%s>
Error while writing new cell map.
Error writing cell map during transform.
error writing data
Error writing output map
G_put_raster_row failed (file system full?)
%s - ERROR writing %s
Unable to properly write output raster map
unable to write map row %d

• G_open_cell_new

"Unable to create raster map <%s>"

Cannot open output raster map <%s>
can't open %s
Error in opening output file <%s>
Unable to create output <%s>
Unable to create raster map <%s>
Unable to create raster map [%s]
Unable to open cell map <%s> for output.\n
Unable to open output file.
Unable to open the cell map MASK.

• G_open_cell_old

"Unable to open raster map <%s>"

Cannot find map %s
Cannot find mapset for %s
Cannot open File %s
Cannot open input raster map <%s>
Cannot open map %s
Cannot open raster map
Cannot open raster map <%s>
Cannot open raster map [%s]
Cannot open raster map [%s]!
Cannot open %s
Cannot open seed map <%s@%s>!
Cannot open terrain raster map <%s@%s>!
Can't open input map
can't open raster map [%s]
can't open raster map <%s> in mapset %s
can't open %s
Could not open raster <%s>
Could not open raster '%s'
Error in opening input file <%s>
Not able to open cellfile for [%s]
Problem opening input file [%s]
Raster file <%s> not found
Raster map [%s] not found  
<%s> cellfile not found
%s: Couldn't open raster <%s@%s>
%s: o_open_file: could not open raster map %s in %s
Unable to open band files.
Unable to open cellfile for [%s]
Unable to open map <%s>
Unable to open MASK
Unable to open raster map [%s]
Unable to open raster <%s>
unable to open [%s] in [%s]
Unable to proceed

• G_find_cell

"Raster map <%s> not found"

albedo raster map <%s> not found
aspin raster map <%s> not found
Cannot find map %s
Cannot find mapset for %s
Cannot find raster map
Cannot find %s
cell file [%s] not found
coefbh raster map <%s> not found
elevin raster map <%s> not found
Input map [%s] in location [%s] in mapset [%s] not found.
latin raster map <%s> not found
linkein raster map <%s> not found
No clump map specified and MASK not set.
Raster file [%s] not found. Exiting.
Raster map [%s] already exists.\nPlease try another.
Raster map <%s> not found
Raster map [%s] not found
Raster <%s> already exist.
Raster <%s> not found
Raster '%s' not found
Requested raster map <%s> not found
[%s] cannot be found!
%s - exits in Mapset <%s>, select another name
slopein raster map <%s> not found
%s: more than %d files not allowed
%s - not found
%s: o_open_file: raster map %s not found
%s: <%s> raster map not found
%s: %s - raster map not found
%s: %s - Unable to find the imaginary-image.
%s: %s - Unable to find the real-image map.
stringliteral
Training map [%s] not found.
Unable to find base map <%s>
Unable to find cell map <%s>
Unable to find cover map <%s>
Unable to find file [%s].
Unable to find input cell map <%s>

• G_find_cell2

"Raster map <%s> not found"

Raster map <%s> not found in current mapset
Raster map <%s> not found
Raster file [%s] not found. Exiting.

• G_find_vector

"Vector map <%s> not found"

Cannot find vector map
Could not find input map <%s>
Could not find input map <%s>.
Could not find input map '%s'.
Could not find input map <%s> in current mapset.
Could not find input map <%s>\n
Could not find input %s
Could not find input %s\n
Could not find input vector map <%s>
Could not find input vector map %s
Could not find network input map '%s'.
Could not find vector map <%s> in current mapset

• G_tempfile

"Unable to open temporary file <%s>"

Unable to write the temporary file      (/display/d.text.freetype/main.c:422)
Unable to open temp file.               (/imagery/i.find/main.c:83)
Unable to open tempfile                 (/raster/r.coin/make_coin.c:83)
Unable to open temporary file <%s>      (/vector/v.in.ascii/in.c:237 /display/d.text/main.c:191 /display/d.text.new/main.c:398 /display/d.title/main.c:117
                                        /raster/r.statistics/o_average.c:42 /raster/r.statistics/o_distrib.c:41 /raster/r.statistics/o_sum.c:43)
                                        (/raster/r.in.ascii/main.c:130) (/raster/r.in.ascii/main.c:160)

Systematic Approach

• Collect all possible error states from functions
• assign error codes for macros?
• G_option() parameters (like output->description = ("Path to resulting ASCII file");)

Note: Would be possible to conctretize your ideas? (MartinL)

Parameters and flags

Fix the parameters and flags. Make it a concept. See proposal in GRASS 5 documents/parameter_proposal.txt

Verbosity levels

Current abstract concept

type	GRASS_VERBOSE	libgis	command line	result	libgis fn
verbose	3	MAX_LEVEL	--verbose	print progress and all messages messages	G_verbose_message()
standard	2	STD_LEVEL		print progress and selected messages	G_message()
brief	1			print only progress information (% done)	G_percent(), G_clicker(), G_important_message()
quiet	0	MIN_LEVEL	--quiet	print nothing (only ERRORs and WARNINGs)	G_warning(), G_fatal_error()
debug		0-5		print debug message at DEBUG level set with g.gisenv	G_debug(#, "")
mute	-		2>&1 > /dev/null	only for use in rare occasions

Proposal

• module output (should be "parsable") is not controlled by GRASS_VERBOSE [use fprintf (stdout, ...)]
• quiet

only warnings and fatal errors are printed

• brief

all G_percent() and G_important_message() (especially connected to progress information??)

• standard

all G_percent() and selected G_message()

• verbose

all G_percent() + G_message() + G_verbose_message()

Modification

• remove verbose level → standard == all G_percent () + G_messages()

why?? --HB

• remove "--verbose" from help pages, manually mention where it does work.

it only does something in a few modules

• move some messages to G_debug()
• move some messages to G_verbose_message()
• move some messages to G_important_message()
• change level numbers to 1, 3, 5
• Add new G_msg(int level, "%format", ...); lib function. Existing G_message() could stay and would be the same as G_msg(LEVEL_STD,...).

Discussion

• HB: I'm quite happy to leave the current system as it is, but use GRASS_MESSAGE_FORMAT=silent to switch off G_percent(),G_clicker() output.

Mixing a sliding verbosity scale plus a binary switch or >= rule for when G_percent() happens in the same variable is very messy IMO.

Alternative Abstract concept

standard	3	PERMSG_MODE	print progress and messages
standard	2	MESSAGE_MODE	print only messages
brief	1	PERCENT_MODE	print only progress information
silent but not mute	0	QUIET_MODE	print nothing (but ERR and WAR)
mute	2>&1 > /dev/null